Stability assessment of surrounding rock in downward mining route supported by slab-wall backfill structure

Stability assessment of surrounding rock in downward mining route supported by slab-wall backfill structure | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Stability assessment of surrounding rock in downward mining route supported by slab-wall backfill structure Yu Yin, Shijiao Yang, Yan He, Jian Pan, Zhenpeng Guo, Junwei Fan, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3774525/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Jun, 2024 Read the published version in Scientific Reports → Version 1 posted 8 You are reading this latest preprint version Abstract Characteristic of ground pressure in surrounding rock is generally considered as the theoretical basis of parameter optimization for stope structure and technology. To explore the feasibility of efficient method for the second-step downward route backfill stopes in Shanjin gold mine, various numerical simulation methods were used to investigate the effect of slab-wall backfill structure on stability of surrounding rock in downward route mining system. The maximum principal stress, artificial false roof stress, and displacement were analyzed to evaluate the level of ground pressure in different mining areas. These results indicate the optimized structural parameters for backfill stopes, which may also provide a low-cost way to achieve a high safety for downward route mining system. Earth and environmental sciences/Solid earth sciences Health sciences/Risk factors Physical sciences/Engineering Backfill mining Slab-wall structure Numerical simulation Ground pressure Stability analysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 1. Introduction Ground pressure becomes one of the major contributors to geological hazards in mining stopes, consisting mainly of the pressure acting on roof, pillars, surrounding rock, and backfill [ 1 – 3 ]. Varying sequences of excavation and backfill result in diverse pressure patterns within the stope [ 4 , 5 ]. Stress concentration and stress reduction areas emerge within specific excavation zones, leading to deformation, movement, and damage of the surrounding rock, ultimately impacting stope stability. Consequently, comprehending the stress transfer dynamics in the mining field is a fundamental prerequisite for ensuring continuous safe mine production and serves as the technical foundation for optimizing mining field structural parameters and procedures [ 6 ]. While the downward approach backfill method is widely employed, its application to smaller stope parameters and higher bottoming backfill strength has received less attention in stope stability studies [ 7 , 8 ]. This paper focuses on the Shanjin gold mine downward approach backfill mining method, utilizing numerical simulations to scrutinize stress distribution and transfer patterns within the downward approach mining field under various plate-wall structural backfill processes. This research aims to provide essential insights for both safe production and process optimization in the mine. 2. Downward Approach Backfill Scheme Shanjin gold mine employs the downward approach backfill method for mining in its underground crushing area. Typically, the underground stope configuration aligns with the ore body's strike direction, featuring a stope width equivalent to the horizontal thickness of the ore body. The length of stope typically falls within the range of 40–60 m, with a midsection height of 40 m and section heights varying between 10–15 m. Additionally, the stratification within the stope measures 4.0 m in height. Stope joints are typically positioned vertically at the ore body's strike center, and each stratification of every stope is further subdivided into multiple mining rooms for ore extraction. The individual mining room's average width is restricted to 4.0 m, while their length typically ranges from 20–40 m. Stope design usually encompasses 10–12 layers for a single midsection, with mining operations progressing sequentially from the uppermost layer. Rock drilling is accomplished using rock drilling carts or YT28 air-leg rock drills, while ore transportation relies on 2m³ shovels. Stope backfill at Shanjin gold mine is executed through a two-step approach: first, employing one-step stope near the upper and lower pans, and second, employing the middle approach. Each step is further subdivided into bottoming high-intensity backfill and standard backfill procedures. The slurry is conveyed from the primary backfill pipeline to the intermediate backfill pipeline, then directed into the stope. The key steps in this process involve field leveling and the installation of a crushed ore bedding layer, followed by the erection of hooked wire mesh and the hanging of pipes. Subsequently, a plastic film is laid, and an artificial overflow channel is constructed. This is followed by the placement of the bottom reinforcement mesh, the erection of hooked wire mesh, and the construction of backfill retaining walls. The false bottom backfill stage ensures a strength of no less than 4.0 MPa, with a backfill height of 1m. Meanwhile, standard backfill attains a height of 3m and a minimum strength of 1.0 MPa. To enhance efficiency, reduce backfill expenses, and expedite the process, four comparative schemes have been developed in response to the mine's current conditions. At the heart of these schemes lies the concept of two-step non-joint top backfill. This innovative approach not only reduces the backfill cost during the two-step standard backfill but also enables quicker transition to the subsequent back mining cycle, thereby improving efficiency. However, it is imperative to conduct a comprehensive assessment of stress transfer patterns and stope stability. Such an analysis serves as a crucial theoretical foundation for on-site production. As shown in Fig. 1 , the control group represents the current mining practice at the site, referred to as the full-joint-top backfill scheme. Under this scheme, the bottom 1m of the second step is filled with high-intensity material at a 1:6 cement-tailing ratio, while the upper portion is filled with ordinary material at a 1:20 cement-tailing ratio, extending to the jointed roof. Four schemes have been devised for this study: Full non-top backfill scheme (scheme 1, Fig. 2 ): In this scheme, the bottom 1m of the second step is filled with high-strength material at a 1:6 cement-tailing ratio, while the upper part is left unfilled. Separate one and fill one scheme (scheme 2, Fig. 3 ): Under this scheme, the first layer of the two-step process is filled, followed by an unfilled layer, and this pattern continues in the lower stopes. Fill one every two scheme (scheme 3, Fig. 4 ): In this approach, the first layer of the second step is filled, while the second and third layers remain unfilled, and this pattern extends to the lower stopes. Every three fills one scheme (scheme 4, Fig. 5 ): Here, the first layer of the second step is filled while the second, third, and fourth layers are left unfilled, and this pattern continues in the lower stope. 3. Numerical simulation study of pressure emergence pattern in mining field 3.1 Rock mechanical parameter The physical and mechanical parameters of surrounding rock for numerical calculation are shown in Table 1 . Table 1 physical and mechanical parameters of surrounding rock samples Categories Density/cm 3 Tensile strength/MPa Bulk modulus/GPa Shear modulus/GPa Rock Shear Strength c/MPa φ/° Surrounding rock 2.65 0.1 4.6 2.8 1.3 45 Ore body 2.65 0.05 2.9 1.7 0.9 40 1:6 High strength backfill material 2.1 0.2 1.3 0.8 0.4 35 1:20 Low strength backfill material 2.1 0.01 0.33 0.2 0.1 25 3.2 Numerical model establishment In pursuit of our numerical simulation objectives, see Fig. 6 , a comprehensive three-dimensional numerical grid model for the stope has been developed, with consideration on ore body conditions and the stope's middle section height [ 9 , 10 ]. Given the inherent complexity of actual mine stope models, we have created an idealized stope model that simplifies relevant conditions. This model aids in examining stress and displacement variations within the backfill and the surrounding rock perimeter during the mining and charging process. Figure 7 illustrates the model section for each scheme. To align with the mining certificate stipulations, which designate a minimum mining elevation of -20m, we conservatively selected the middle section at -20m for our study's focal point and subsequently constructed the grid model. For ease of comparison across different strategies, the three-dimensional numerical grid model within the middle section spans 48 m in height, divided into 12 layers, with each layer measuring 4.0 m in height. The stope spans 4.0 m in width, 197 m in length, and 168 m in height. Tetrahedral grids have been employed, resulting in a total of 695,000 grids and 125,000 nodes. 3.3 Analysis of simulation results 3.3.1 Initial ground stress As shown in Fig. 8 , the numerical calculations commence with the establishment of initial stress equilibrium to align the model's stress conditions with actual stress patterns. This simulation accounts for self-gravity stress, considering a stope model situated at an elevation of -20 m with an approximate burial depth of 500 m. Following the initial stress equilibration, the maximum principal stress registers around 14 MPa, while at the model's base, it reaches approximately 17.5 MPa. 3.3.2 Distribution pattern of maximum principal stresses in the stope perimeter rock After the stope is mined, the near stope perimeter rock starts to deform and release stress due to the loss of original rock support. After the near stope perimeter rock releases the stress through displacement, the load of the overlying rock layer will be transferred to the far stope perimeter rock, and the displacement of the far stope perimeter rock is limited, which cannot release the stress, resulting in the stress of the far stope perimeter rock increasing. In the following maximum principal stress cloud diagram of each scheme, the stress in the far-field perimeter rock is significantly increased, in which the upper right and lower left corners of the stope are the stress concentration areas [ 11 – 13 ]. In the subsequent section, we will conduct a comparative analysis of stress distribution among various schemes to gain insight into how stress manifests differently in these backfill schemes. This analysis will allow us to evaluate the strengths and weaknesses of each scheme. Figure 9 presents the cloud diagrams illustrating the distribution of maximum principal stress for different backfill schemes. In these diagrams, the blue areas represent lower stress regions, while the red areas indicate higher stress regions. It becomes evident that, post-stope mining and backfill, both the backfill and the surrounding rock on the upper and lower sections of the stope experience reduced stress levels. Furthermore, the upper section demonstrates lower stress levels compared to the lower section, and the stress reduction area is also more extensive. Following stope mining, the nearby perimeter rock initiates deformation and stress release due to the absence of original rock support. As the nearby perimeter rock releases stress through displacement, the load from the overlying rock layer is transferred to the far perimeter rock. However, the displacement of the far perimeter rock is constrained, preventing the release of stress, leading to an increase in stress within the far perimeter rock. Subsequently, in the forthcoming maximum principal stress cloud diagram for each scheme, it becomes evident that stress significantly amplifies in the far-field perimeter rock, with stress concentration areas particularly pronounced in the upper-right and lower-left corners of the stope. The preceding description provides a fundamental overview of stress release and transfer patterns in the surrounding rock resulting from various stope mining schemes. Notably, the distribution of load carried by the backfill varies among these schemes, consequently influencing the manner in which stress is alleviated or intensified within the surrounding rock. The data pertaining to backfill and perimeter rock stress within the stope has been gathered to construct stress change curves for both the backfill and perimeter rock under different schemes, as shown in Fig. 10 . Based on the graphs illustrating the variation in maximum principal stress distribution under different scheme conditions, the following patterns emerge: Far mine perimeter rock: This region, located approximately 20–30 meters from the mine's edge, experiences the most significant increase in principal stresses within the perimeter rock. The initial equilibrium stress here, approximately 14–17 MPa, escalates to 19–23 MPa. As the number of top-filled stopes decreases, the stress in this far-stope perimeter rock consistently increases across various scenarios. This phenomenon is attributed to the diminished load-bearing capacity of fewer backfill and roofing stopes, causing the excess load to transfer to the distant perimeter rock. Consequently, the greater the backfill load-bearing capacity, the more effectively it can alleviate the stress concentration within the remote perimeter rock. Near-stope perimeter rock: this area, extending approximately 15 m from the stope's edge, experiences reduced perimeter rock stress. Stress levels fluctuate in response to variations in the number of backfill and roofing stopes and exhibit an opposite trend compared to the far-stope perimeter rock. When comparing different backfill schemes, a reduction in the number of top-backfill stopes leads to a gradual decrease in internal stress within the perimeter rock near the stope. Essentially, this signifies that a higher rate of roof backfill corresponds to increased bearing capacity and, subsequently, higher stress levels within the near-stope perimeter rock. It suggests that during the backfill load-bearing process, the near-mine perimeter rock also shares the burden of perimeter rock stress. This, to a certain extent, constrains perimeter rock deformation, resulting in reduced stress release and a reduced likelihood of perimeter rock fissure development. This approach helps maintain perimeter rock integrity and improves its load-bearing capacity. High-strength backfill at stope bottom: notably, the maximum principal stresses in the high-strength backfills at the stope's bottom exhibit distinct differences. Among the various schemes, the full roof backfill scheme consistently yields the highest maximum stress in the backfill at the stope's bottom. This is followed by the alternate one and alternate two schemes, with the lowest stress levels observed in the alternate three and full non-roof backfill schemes. As shown in Fig. 11 , it becomes evident that scheme II and scheme III, featuring high-strength backfills (artificial false roofs), share similar conditions. These conditions entail lower stope backfill and roof jointing. Conversely, option 1 and option 4 involve artificial false roofs but lack lower stope backfill. Under otherwise identical conditions, the occurrence of similar internal stress in stope artificial false roofs is influenced significantly by whether the lower stope includes backfill to catch the top, illustrating a substantial impact. In summary, the backfill stope demonstrates positive and beneficial effects on the stress transfer and release in the surrounding rock. It effectively leverages the backfill capacity to restrain surrounding rock displacement, thereby altering the stress distribution within the stope's vicinity and mitigating stress concentration phenomena. It is worth noting that the backfill capacity to bear stress transfer is constrained by its stiffness relative to the surrounding rock. The backfill exhibits significantly lower stiffness compared to the surrounding rock body, making it unable to fully absorb all stress transfers. Therefore, a blanket increase in backfill volume and backfill strength may not optimally utilize the self-supporting capacity of the surrounding rock [ 14 ]. Instead, it can lead to an excessive safety factor for the stope, incurring substantial economic costs. An appropriate backfill strategy should be carefully selected, taking into consideration the mining method and the quality characteristics of the surrounding rock. This strategy aims to strike a balance between safety and economic factors concerning both the backfill and the stability of the surrounding rock. While prioritizing the mine's safety, it is possible to optimize the stope backfill volume by harnessing the inherent load-bearing capacity of the surrounding rock and pushing the upper limits of the backfill safe load-bearing capacity. This judicious reduction in backfill volume not only leads to cost savings but also enhances the efficiency of stope operations. 3.3.3 Comparative analysis of artificial false roof stresses The mining method employed in this mine is the downward approach backfill method, which involves a specific sequence of ore extraction. Initially, ore bodies near the upper and lower sections of the stope are mined, followed by the intermediate ore bodies. Notably, the sections near the upper and lower areas have already undergone proper roofing and backfill to safeguard the perimeter rock. Consequently, there is no requirement to assess the stability of the exposed perimeter rock in these upper and lower sections of the stope. Conversely, the stability of the intermediate mining sections primarily hinges on the integrity of the artificial false roof within the stope. As per rule 3 in section 3.3.2 , it becomes evident that the internal stress magnitude within the artificial false roof is contingent on whether the upper and lower quarries are filled. The stability of this artificial false roof holds paramount significance as it directly impacts the safety of the mining operation in the lower stopes [ 15 , 16 ]. To ascertain the safety of the artificial false roof, a comparison is drawn between the compressive strength of the artificial false roof and the maximum compressive stress calculated through numerical simulation. The results of this numerical simulation employ an elastic-plastic model to compute the maximum principal stress variation in the artificial false roof within the stope, depicted in Fig. 12 , revealing the following insights: The maximum principal stresses predominantly remain below 4 MPa in all scenarios, with isolated areas close to the surrounding rocks of the lower plate experiencing maximum principal stresses of up to 5 MPa. Stresses are higher when the upper and lower stopes of the artificial false roofs are backfilled, decreasing in the absence of such backfill. Importantly, the internal stress in the artificial false roof numerically remains lower than its uniaxial compressive strength. The maximum principal stress within the artificial false roof correlates with the presence or absence of upper and lower quarry backfill. In ideal elastic-plastic conditions, when the quarries are not filled, the artificial false roof enters a plastic state, causing the backfill to exceed its elastic deformation and initiate stress release, ultimately reducing the maximum principal stress. Moving from the uppermost to the lowermost level of the stope, the internal stress within the artificial false roof exhibits a gradual decline. This phenomenon can be attributed to the fact that the lower part of the mining operation remains undisturbed until the upper part is mined, leading to larger surrounding rock displacement and heavier backfill load [ 17 – 19 ]. Consequently, the operating stope roof bears a relatively smaller load, ensuring enhanced stability. Conversely, the artificial false roof in the upper stope sustains a greater load from the surrounding rock for a more extended period, compromising its stability. When employing the interval backfill scheme, it becomes evident that interval backfill provides a protective effect on the artificial false roof. Upper and lower quarry backfill improves the stress environment within the artificial false roof, transitioning from one-dimensional pressure exerted by the surrounding rock on both sides to two-dimensional or three-dimensional pressure. In conclusion, the magnitude of compressive stress within the artificial false roof is contingent on the backfill conditions and stope location. Numerical simulation results reveal that the internal compressive stress in the artificial false roof remains below its 4.0 MPa compressive strength threshold. Particularly noteworthy is the fact that the internal stresses within the artificial false roofs in the lowest stope are consistently around 2.0 MPa, and do not surpass the compressive strength of the backfill [ 20 ]. 3.3.4 Displacement analysis Stress and displacement within a rock body are interconnected physical parameters. During ore extraction from the stope, the original ore body's loads are transferred to the surrounding rock mass. The augmented load on the surrounding rock induces both volumetric and shear deformations in the rock mass. Consequently, the mine floor serves as a space for rock deformation. As the surrounding rock mass deforms, internal stress loads are gradually released, leading to the transfer of stress loads outward. This process continues until the outer perimeter rock is constrained by space, ceases to deform further, and stress is no longer transmitted to deeper layers. Therefore, displacement serves as a vital parameter for analyzing the stress transfer characteristics of the surrounding rock and assessing its integrity. Vertical displacement is the primary form of rock displacement, with the upper stope disk experiencing relatively significant displacement. As the number of unfilled roof quarries increases, the displacement of the upper disk's perimeter rock grows progressively larger. Data on perimeter rock displacement were collected along the upper disk's boundary within the mining field, yielding displacement curves for different scenarios. Figure 13 exhibits the displacement curves of the perimeter rock in the upper section of the mining site: (1) There were two significant increases in perimeter rock displacement in the upper part of the stope among various scenarios. The first occurred between the full-jointed top backfill and partial-jointed top backfill, while the second was observed between the partial-jointed top and no-jointed top backfill scheme. This underscores the substantial impact of stope backfill on reducing upper disk displacement. (2) In the vertical direction, perimeter rock displacement gradually increases as one moves away from the working face, reaching its maximum near the top of the middle section and gradually decreasing further upward. The disparity in perimeter rock displacement among different backfill schemes primarily lies in the area away from the bottom working face. (3) Within the 10 ~ 12m range from the mining operation face at the bottom of this middle section, there is no noticeable difference in upper disk perimeter rock displacement between different scenarios. The values and development trends of perimeter rock displacement remain consistent. These observations suggest that the displacement of the surrounding rock near the mining face is minimally affected by the backfill process during ore body mining [ 21 ], which may be attributed to the much greater stiffness of the surrounding rock compared to the backfill, with the backfill mainly improving stress conditions, maintaining surrounding rock integrity, and retarding displacement. 4. Conclusion A comparative analysis of four scenarios involving two-step unjointed top backfill in the downward approach yields the following conclusions: (1) In line with the maximum principal stress analysis, backfill serves to enhance the structural integrity of the stope perimeter rock and maintain its stability. Nonetheless, the backfill's capacity to bear stress transfer is notably limited due to its low stiffness. It cannot fully absorb the entire stress transfer. Blindly augmenting both the backfill volume and backfill strength may fail to harness the natural load-bearing capacity of the perimeter rock, potentially leading to an excessive safety factor within the stope. This could result in substantial economic costs. (2) Compressive stress experienced by the artificial false roof in various schemes remains below its compressive strength of 4 MPa. Generally, the internal stress in the lower part of the middle section of the stope's artificial false roof is modest, hovering around 2 MPa—well within the backfill's compressive strength threshold. (3) Displacement analysis indicates that within the 10 ~ 12m range above the mining face, the stope's perimeter rock is minimally affected by the spatial constraints of the excavation surface, resulting in negligible displacement. Consequently, deformation pressure exerted on the backfill remains low. Furthermore, initial displacement levels of the surrounding rock remain consistent across different backfill programs, indicating that the backfill's impact on surrounding rock deformation is insignificant. (4) By comparing the magnitude and trends of stress displacement among various backfill schemes, it becomes evident that, within the 10 ~ 12m vicinity near the mining face in the middle section of the stope, stress displacement exhibits little variation among different schemes. Consequently, the stability of the backfill should be similar within this region. As a result, a field test may be considered for the every-three-fills-one backfill scheme. Conversely, stress displacement in the upper part of the stope surpasses that of the full roof backfill scheme, indicating higher safety risks and rendering it unsuitable for use. Declarations Funding The present study was financially supported by the Natural Science Foundation of Hunan Province (2023JJ40546), and the Research Project of Education Department of Hunan Province (21A0264). Author Contribution Yu Yin and Yan He wrote the main manuscript text;Shijiao Yang and Jian Pan designed the methodology and completed the data curation for this manuscript;Zhenpeng Guo, Junwei Fan, and Zhipeng Wang prepared figures 1-13 in this manuscript;All authors reviewed the manuscript. 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Cite Share Download PDF Status: Published Journal Publication published 14 Jun, 2024 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 21 Mar, 2024 Reviews received at journal 05 Feb, 2024 Reviewers agreed at journal 04 Feb, 2024 Reviewers invited by journal 04 Feb, 2024 Editor assigned by journal 04 Feb, 2024 Editor invited by journal 21 Dec, 2023 Submission checks completed at journal 21 Dec, 2023 First submitted to journal 18 Dec, 2023 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3774525","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":263260779,"identity":"c84b47f9-964d-4b66-b45a-3f2b0be14e07","order_by":0,"name":"Yu Yin","email":"","orcid":"","institution":"University of South China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Yin","suffix":""},{"id":263260780,"identity":"390cdc9b-daf0-4ec6-b46d-69e356666671","order_by":1,"name":"Shijiao Yang","email":"","orcid":"","institution":"University of South China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shijiao","middleName":"","lastName":"Yang","suffix":""},{"id":263260783,"identity":"424bf60d-bd55-4bfb-870a-b980cbc0f980","order_by":2,"name":"Yan He","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAuElEQVRIiWNgGAWjYBACgwMMbBIMFRCOBAlazpCiRbIBqIWxjRQt/Oxnj0l8nHfYnr+B+eBtHga7PIJa2Hjy0n/O3HY4ccYBtmRrHobkYsJaGHLMpHm3HU4wYOAxk+ZhOJDYQFAL/xsz6b9zDtsbMPB/I1KLBNAWxobDjBsYeNiI1fLGTLLnWHrijMNsxpZzDJKJcViOmcSPGmt7/vbmhzfeVNgR1oIAzCDCgHj1o2AUjIJRMArwAABkLTNcwo+i8gAAAABJRU5ErkJggg==","orcid":"","institution":"University of South China","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Yan","middleName":"","lastName":"He","suffix":""},{"id":263260786,"identity":"d9c8c6e8-a366-4f0c-86e0-fe113d4ac990","order_by":3,"name":"Jian Pan","email":"","orcid":"","institution":"Sinosteel Maanshan General lnstitute of Mining Research Co., Ltd","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jian","middleName":"","lastName":"Pan","suffix":""},{"id":263260787,"identity":"2e65bc25-5c66-4131-af3a-2df556188b1d","order_by":4,"name":"Zhenpeng Guo","email":"","orcid":"","institution":"Sinosteel Maanshan General lnstitute of Mining Research Co., Ltd","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zhenpeng","middleName":"","lastName":"Guo","suffix":""},{"id":263260788,"identity":"9bd4993b-a9ae-4d9a-a759-9abb9e8f6df6","order_by":5,"name":"Junwei Fan","email":"","orcid":"","institution":"University of South China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Junwei","middleName":"","lastName":"Fan","suffix":""},{"id":263260789,"identity":"dc908994-cbe1-4c64-af60-010e6eaff7a0","order_by":6,"name":"Zhipeng Wang","email":"","orcid":"","institution":"University of South China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zhipeng","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2023-12-19 02:44:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3774525/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3774525/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-024-64620-5","type":"published","date":"2024-06-14T15:39:50+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":48836902,"identity":"ba3784a1-6c9f-4b7c-88ef-12fc7c3a8e2b","added_by":"auto","created_at":"2023-12-27 05:53:24","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":151171,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the control mining method\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/ec3f8e8f4a093aa91d0157e7.png"},{"id":48836897,"identity":"343fefba-8a7f-4d38-b275-f3a5e3d09c38","added_by":"auto","created_at":"2023-12-27 05:53:24","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":110632,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the full-slab-wall structure infill mining method\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/dcc894efbc663c3d71b49aa9.png"},{"id":48836895,"identity":"cd5198cb-eb54-4852-91b6-dbbd87f222a4","added_by":"auto","created_at":"2023-12-27 05:53:24","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":128164,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of infill method with separate one and fill one slab wall structure\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/06b3eda0cd1bdd4e31d566b2.png"},{"id":48837436,"identity":"0a84cfeb-4ceb-4e85-be5c-bc858dfce20c","added_by":"auto","created_at":"2023-12-27 06:01:24","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":121339,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of backfill method of fill one every two slab wall structure\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/e058906a832f4c5956fcf157.png"},{"id":48836898,"identity":"88ab7f47-2a53-4a0e-946d-d556f21ce768","added_by":"auto","created_at":"2023-12-27 05:53:24","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":116629,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of backfill method of every three fills one slab wall structure\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/a9cf4e1dc69cb7c938a9ba43.png"},{"id":48838405,"identity":"1873c8c0-5d41-483b-9dba-09e08bc802a0","added_by":"auto","created_at":"2023-12-27 06:17:24","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":333721,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of numerical model\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/923321981606d26b66c5f10d.png"},{"id":48837587,"identity":"ce176001-dfd2-4306-824b-3396e8e20f1e","added_by":"auto","created_at":"2023-12-27 06:09:24","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":748556,"visible":true,"origin":"","legend":"\u003cp\u003eModeled sections of different slab wall structure backfill schemes\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/b27c6f1ff353e1df9661980d.png"},{"id":48837589,"identity":"4a0c2ac2-d18d-4e11-97f9-a1fd3b99ad8b","added_by":"auto","created_at":"2023-12-27 06:09:25","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":139976,"visible":true,"origin":"","legend":"\u003cp\u003eInitial stress equilibrium\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/b1880dd13fd2c3220b38cb28.png"},{"id":48837437,"identity":"72c94555-9c2e-43e0-a2bd-25c5cff36b99","added_by":"auto","created_at":"2023-12-27 06:01:24","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":228149,"visible":true,"origin":"","legend":"\u003cp\u003eCloud diagram of the maximum principal stress\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/302e42e4a6286f721d7acb38.png"},{"id":48836903,"identity":"df535914-bd34-49d9-8ac1-f3d86b6a6b0a","added_by":"auto","created_at":"2023-12-27 05:53:25","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":328431,"visible":true,"origin":"","legend":"\u003cp\u003eMaximum principal stress variation curve of the backfill and surrounding rock of the stope\u003c/p\u003e","description":"","filename":"floatimage10.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/79e01be640506a8a8b4e8d44.png"},{"id":48837590,"identity":"bba830ef-b10f-47ec-a10c-67c5e1a541ad","added_by":"auto","created_at":"2023-12-27 06:09:25","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":934687,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the location of the stope and perimeter rock stress collection\u003c/p\u003e","description":"","filename":"floatimage11.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/35052f41db9dbdca48513bd4.png"},{"id":48837442,"identity":"f641f841-b5c3-4dbf-958a-fa4c92c6d67b","added_by":"auto","created_at":"2023-12-27 06:01:25","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":569058,"visible":true,"origin":"","legend":"\u003cp\u003eMaximum principal stress curve\u003c/p\u003e","description":"","filename":"floatimage12.png","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/cebd169066a45b7a7abf39fd.png"},{"id":58823477,"identity":"942a4263-dbe8-4b4c-94b7-f1ea7f70f5f9","added_by":"auto","created_at":"2024-06-21 17:00:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4048353,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3774525/v1/34773da1-7f1b-43a3-9179-7b04d595b80b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Stability assessment of surrounding rock in downward mining route supported by slab-wall backfill structure","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eGround pressure becomes one of the major contributors to geological hazards in mining stopes, consisting mainly of the pressure acting on roof, pillars, surrounding rock, and backfill [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Varying sequences of excavation and backfill result in diverse pressure patterns within the stope [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Stress concentration and stress reduction areas emerge within specific excavation zones, leading to deformation, movement, and damage of the surrounding rock, ultimately impacting stope stability. Consequently, comprehending the stress transfer dynamics in the mining field is a fundamental prerequisite for ensuring continuous safe mine production and serves as the technical foundation for optimizing mining field structural parameters and procedures [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. While the downward approach backfill method is widely employed, its application to smaller stope parameters and higher bottoming backfill strength has received less attention in stope stability studies [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. This paper focuses on the Shanjin gold mine downward approach backfill mining method, utilizing numerical simulations to scrutinize stress distribution and transfer patterns within the downward approach mining field under various plate-wall structural backfill processes. This research aims to provide essential insights for both safe production and process optimization in the mine.\u003c/p\u003e"},{"header":"2. Downward Approach Backfill Scheme","content":"\u003cp\u003eShanjin gold mine employs the downward approach backfill method for mining in its underground crushing area. Typically, the underground stope configuration aligns with the ore body's strike direction, featuring a stope width equivalent to the horizontal thickness of the ore body. The length of stope typically falls within the range of 40\u0026ndash;60 m, with a midsection height of 40 m and section heights varying between 10\u0026ndash;15 m. Additionally, the stratification within the stope measures 4.0 m in height. Stope joints are typically positioned vertically at the ore body's strike center, and each stratification of every stope is further subdivided into multiple mining rooms for ore extraction. The individual mining room's average width is restricted to 4.0 m, while their length typically ranges from 20\u0026ndash;40 m. Stope design usually encompasses 10\u0026ndash;12 layers for a single midsection, with mining operations progressing sequentially from the uppermost layer. Rock drilling is accomplished using rock drilling carts or YT28 air-leg rock drills, while ore transportation relies on 2m\u0026sup3; shovels.\u003c/p\u003e \u003cp\u003eStope backfill at Shanjin gold mine is executed through a two-step approach: first, employing one-step stope near the upper and lower pans, and second, employing the middle approach. Each step is further subdivided into bottoming high-intensity backfill and standard backfill procedures. The slurry is conveyed from the primary backfill pipeline to the intermediate backfill pipeline, then directed into the stope. The key steps in this process involve field leveling and the installation of a crushed ore bedding layer, followed by the erection of hooked wire mesh and the hanging of pipes. Subsequently, a plastic film is laid, and an artificial overflow channel is constructed. This is followed by the placement of the bottom reinforcement mesh, the erection of hooked wire mesh, and the construction of backfill retaining walls. The false bottom backfill stage ensures a strength of no less than 4.0 MPa, with a backfill height of 1m. Meanwhile, standard backfill attains a height of 3m and a minimum strength of 1.0 MPa.\u003c/p\u003e \u003cp\u003eTo enhance efficiency, reduce backfill expenses, and expedite the process, four comparative schemes have been developed in response to the mine's current conditions. At the heart of these schemes lies the concept of two-step non-joint top backfill. This innovative approach not only reduces the backfill cost during the two-step standard backfill but also enables quicker transition to the subsequent back mining cycle, thereby improving efficiency. However, it is imperative to conduct a comprehensive assessment of stress transfer patterns and stope stability. Such an analysis serves as a crucial theoretical foundation for on-site production.\u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, the control group represents the current mining practice at the site, referred to as the full-joint-top backfill scheme. Under this scheme, the bottom 1m of the second step is filled with high-intensity material at a 1:6 cement-tailing ratio, while the upper portion is filled with ordinary material at a 1:20 cement-tailing ratio, extending to the jointed roof.\u003c/p\u003e \u003cp\u003eFour schemes have been devised for this study:\u003c/p\u003e \u003cp\u003eFull non-top backfill scheme (scheme 1, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e): In this scheme, the bottom 1m of the second step is filled with high-strength material at a 1:6 cement-tailing ratio, while the upper part is left unfilled.\u003c/p\u003e \u003cp\u003eSeparate one and fill one scheme (scheme 2, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e): Under this scheme, the first layer of the two-step process is filled, followed by an unfilled layer, and this pattern continues in the lower stopes.\u003c/p\u003e \u003cp\u003eFill one every two scheme (scheme 3, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e): In this approach, the first layer of the second step is filled, while the second and third layers remain unfilled, and this pattern extends to the lower stopes.\u003c/p\u003e \u003cp\u003eEvery three fills one scheme (scheme 4, Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e): Here, the first layer of the second step is filled while the second, third, and fourth layers are left unfilled, and this pattern continues in the lower stope.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"3. Numerical simulation study of pressure emergence pattern in mining field","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Rock mechanical parameter\u003c/h2\u003e \u003cp\u003eThe physical and mechanical parameters of surrounding rock for numerical calculation are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ephysical and mechanical parameters of surrounding rock samples\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCategories\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDensity/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTensile strength/MPa\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eBulk modulus/GPa\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eShear modulus/GPa\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eRock Shear Strength\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ec/MPa\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eφ/\u0026deg;\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurrounding rock\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOre body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1:6 High strength backfill material\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1:20 Low strength backfill material\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Numerical model establishment\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn pursuit of our numerical simulation objectives, see Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, a comprehensive three-dimensional numerical grid model for the stope has been developed, with consideration on ore body conditions and the stope's middle section height [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Given the inherent complexity of actual mine stope models, we have created an idealized stope model that simplifies relevant conditions. This model aids in examining stress and displacement variations within the backfill and the surrounding rock perimeter during the mining and charging process.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e illustrates the model section for each scheme. To align with the mining certificate stipulations, which designate a minimum mining elevation of -20m, we conservatively selected the middle section at -20m for our study's focal point and subsequently constructed the grid model. For ease of comparison across different strategies, the three-dimensional numerical grid model within the middle section spans 48 m in height, divided into 12 layers, with each layer measuring 4.0 m in height. The stope spans 4.0 m in width, 197 m in length, and 168 m in height. Tetrahedral grids have been employed, resulting in a total of 695,000 grids and 125,000 nodes.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Analysis of simulation results\u003c/h2\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e3.3.1 Initial ground stress\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e, the numerical calculations commence with the establishment of initial stress equilibrium to align the model's stress conditions with actual stress patterns. This simulation accounts for self-gravity stress, considering a stope model situated at an elevation of -20 m with an approximate burial depth of 500 m. Following the initial stress equilibration, the maximum principal stress registers around 14 MPa, while at the model's base, it reaches approximately 17.5 MPa.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e3.3.2 Distribution pattern of maximum principal stresses in the stope perimeter rock\u003c/h2\u003e \u003cp\u003eAfter the stope is mined, the near stope perimeter rock starts to deform and release stress due to the loss of original rock support. After the near stope perimeter rock releases the stress through displacement, the load of the overlying rock layer will be transferred to the far stope perimeter rock, and the displacement of the far stope perimeter rock is limited, which cannot release the stress, resulting in the stress of the far stope perimeter rock increasing. In the following maximum principal stress cloud diagram of each scheme, the stress in the far-field perimeter rock is significantly increased, in which the upper right and lower left corners of the stope are the stress concentration areas [\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn the subsequent section, we will conduct a comparative analysis of stress distribution among various schemes to gain insight into how stress manifests differently in these backfill schemes. This analysis will allow us to evaluate the strengths and weaknesses of each scheme.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e presents the cloud diagrams illustrating the distribution of maximum principal stress for different backfill schemes. In these diagrams, the blue areas represent lower stress regions, while the red areas indicate higher stress regions. It becomes evident that, post-stope mining and backfill, both the backfill and the surrounding rock on the upper and lower sections of the stope experience reduced stress levels. Furthermore, the upper section demonstrates lower stress levels compared to the lower section, and the stress reduction area is also more extensive.\u003c/p\u003e \u003cp\u003eFollowing stope mining, the nearby perimeter rock initiates deformation and stress release due to the absence of original rock support. As the nearby perimeter rock releases stress through displacement, the load from the overlying rock layer is transferred to the far perimeter rock. However, the displacement of the far perimeter rock is constrained, preventing the release of stress, leading to an increase in stress within the far perimeter rock. Subsequently, in the forthcoming maximum principal stress cloud diagram for each scheme, it becomes evident that stress significantly amplifies in the far-field perimeter rock, with stress concentration areas particularly pronounced in the upper-right and lower-left corners of the stope.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe preceding description provides a fundamental overview of stress release and transfer patterns in the surrounding rock resulting from various stope mining schemes. Notably, the distribution of load carried by the backfill varies among these schemes, consequently influencing the manner in which stress is alleviated or intensified within the surrounding rock. The data pertaining to backfill and perimeter rock stress within the stope has been gathered to construct stress change curves for both the backfill and perimeter rock under different schemes, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eBased on the graphs illustrating the variation in maximum principal stress distribution under different scheme conditions, the following patterns emerge:\u003c/p\u003e \u003cp\u003eFar mine perimeter rock: This region, located approximately 20\u0026ndash;30 meters from the mine's edge, experiences the most significant increase in principal stresses within the perimeter rock. The initial equilibrium stress here, approximately 14\u0026ndash;17 MPa, escalates to 19\u0026ndash;23 MPa. As the number of top-filled stopes decreases, the stress in this far-stope perimeter rock consistently increases across various scenarios. This phenomenon is attributed to the diminished load-bearing capacity of fewer backfill and roofing stopes, causing the excess load to transfer to the distant perimeter rock. Consequently, the greater the backfill load-bearing capacity, the more effectively it can alleviate the stress concentration within the remote perimeter rock.\u003c/p\u003e \u003cp\u003eNear-stope perimeter rock: this area, extending approximately 15 m from the stope's edge, experiences reduced perimeter rock stress. Stress levels fluctuate in response to variations in the number of backfill and roofing stopes and exhibit an opposite trend compared to the far-stope perimeter rock. When comparing different backfill schemes, a reduction in the number of top-backfill stopes leads to a gradual decrease in internal stress within the perimeter rock near the stope. Essentially, this signifies that a higher rate of roof backfill corresponds to increased bearing capacity and, subsequently, higher stress levels within the near-stope perimeter rock. It suggests that during the backfill load-bearing process, the near-mine perimeter rock also shares the burden of perimeter rock stress. This, to a certain extent, constrains perimeter rock deformation, resulting in reduced stress release and a reduced likelihood of perimeter rock fissure development. This approach helps maintain perimeter rock integrity and improves its load-bearing capacity.\u003c/p\u003e \u003cp\u003eHigh-strength backfill at stope bottom: notably, the maximum principal stresses in the high-strength backfills at the stope's bottom exhibit distinct differences. Among the various schemes, the full roof backfill scheme consistently yields the highest maximum stress in the backfill at the stope's bottom. This is followed by the alternate one and alternate two schemes, with the lowest stress levels observed in the alternate three and full non-roof backfill schemes. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e11\u003c/span\u003e, it becomes evident that scheme II and scheme III, featuring high-strength backfills (artificial false roofs), share similar conditions. These conditions entail lower stope backfill and roof jointing. Conversely, option 1 and option 4 involve artificial false roofs but lack lower stope backfill. Under otherwise identical conditions, the occurrence of similar internal stress in stope artificial false roofs is influenced significantly by whether the lower stope includes backfill to catch the top, illustrating a substantial impact.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn summary, the backfill stope demonstrates positive and beneficial effects on the stress transfer and release in the surrounding rock. It effectively leverages the backfill capacity to restrain surrounding rock displacement, thereby altering the stress distribution within the stope's vicinity and mitigating stress concentration phenomena. It is worth noting that the backfill capacity to bear stress transfer is constrained by its stiffness relative to the surrounding rock. The backfill exhibits significantly lower stiffness compared to the surrounding rock body, making it unable to fully absorb all stress transfers. Therefore, a blanket increase in backfill volume and backfill strength may not optimally utilize the self-supporting capacity of the surrounding rock [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Instead, it can lead to an excessive safety factor for the stope, incurring substantial economic costs.\u003c/p\u003e \u003cp\u003eAn appropriate backfill strategy should be carefully selected, taking into consideration the mining method and the quality characteristics of the surrounding rock. This strategy aims to strike a balance between safety and economic factors concerning both the backfill and the stability of the surrounding rock. While prioritizing the mine's safety, it is possible to optimize the stope backfill volume by harnessing the inherent load-bearing capacity of the surrounding rock and pushing the upper limits of the backfill safe load-bearing capacity. This judicious reduction in backfill volume not only leads to cost savings but also enhances the efficiency of stope operations.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003e3.3.3 Comparative analysis of artificial false roof stresses\u003c/h2\u003e \u003cp\u003eThe mining method employed in this mine is the downward approach backfill method, which involves a specific sequence of ore extraction. Initially, ore bodies near the upper and lower sections of the stope are mined, followed by the intermediate ore bodies. Notably, the sections near the upper and lower areas have already undergone proper roofing and backfill to safeguard the perimeter rock. Consequently, there is no requirement to assess the stability of the exposed perimeter rock in these upper and lower sections of the stope. Conversely, the stability of the intermediate mining sections primarily hinges on the integrity of the artificial false roof within the stope.\u003c/p\u003e \u003cp\u003eAs per rule 3 in section \u003cspan refid=\"Sec8\" class=\"InternalRef\"\u003e3.3.2\u003c/span\u003e, it becomes evident that the internal stress magnitude within the artificial false roof is contingent on whether the upper and lower quarries are filled. The stability of this artificial false roof holds paramount significance as it directly impacts the safety of the mining operation in the lower stopes [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. To ascertain the safety of the artificial false roof, a comparison is drawn between the compressive strength of the artificial false roof and the maximum compressive stress calculated through numerical simulation. The results of this numerical simulation employ an elastic-plastic model to compute the maximum principal stress variation in the artificial false roof within the stope, depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003e, revealing the following insights:\u003c/p\u003e \u003cp\u003eThe maximum principal stresses predominantly remain below 4 MPa in all scenarios, with isolated areas close to the surrounding rocks of the lower plate experiencing maximum principal stresses of up to 5 MPa. Stresses are higher when the upper and lower stopes of the artificial false roofs are backfilled, decreasing in the absence of such backfill. Importantly, the internal stress in the artificial false roof numerically remains lower than its uniaxial compressive strength.\u003c/p\u003e \u003cp\u003eThe maximum principal stress within the artificial false roof correlates with the presence or absence of upper and lower quarry backfill. In ideal elastic-plastic conditions, when the quarries are not filled, the artificial false roof enters a plastic state, causing the backfill to exceed its elastic deformation and initiate stress release, ultimately reducing the maximum principal stress.\u003c/p\u003e \u003cp\u003eMoving from the uppermost to the lowermost level of the stope, the internal stress within the artificial false roof exhibits a gradual decline. This phenomenon can be attributed to the fact that the lower part of the mining operation remains undisturbed until the upper part is mined, leading to larger surrounding rock displacement and heavier backfill load [\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Consequently, the operating stope roof bears a relatively smaller load, ensuring enhanced stability. Conversely, the artificial false roof in the upper stope sustains a greater load from the surrounding rock for a more extended period, compromising its stability.\u003c/p\u003e \u003cp\u003eWhen employing the interval backfill scheme, it becomes evident that interval backfill provides a protective effect on the artificial false roof. Upper and lower quarry backfill improves the stress environment within the artificial false roof, transitioning from one-dimensional pressure exerted by the surrounding rock on both sides to two-dimensional or three-dimensional pressure.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn conclusion, the magnitude of compressive stress within the artificial false roof is contingent on the backfill conditions and stope location. Numerical simulation results reveal that the internal compressive stress in the artificial false roof remains below its 4.0 MPa compressive strength threshold. Particularly noteworthy is the fact that the internal stresses within the artificial false roofs in the lowest stope are consistently around 2.0 MPa, and do not surpass the compressive strength of the backfill [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section3\"\u003e \u003ch2\u003e3.3.4 Displacement analysis\u003c/h2\u003e \u003cp\u003eStress and displacement within a rock body are interconnected physical parameters. During ore extraction from the stope, the original ore body's loads are transferred to the surrounding rock mass. The augmented load on the surrounding rock induces both volumetric and shear deformations in the rock mass. Consequently, the mine floor serves as a space for rock deformation. As the surrounding rock mass deforms, internal stress loads are gradually released, leading to the transfer of stress loads outward. This process continues until the outer perimeter rock is constrained by space, ceases to deform further, and stress is no longer transmitted to deeper layers. Therefore, displacement serves as a vital parameter for analyzing the stress transfer characteristics of the surrounding rock and assessing its integrity.\u003c/p\u003e \u003cp\u003eVertical displacement is the primary form of rock displacement, with the upper stope disk experiencing relatively significant displacement. As the number of unfilled roof quarries increases, the displacement of the upper disk's perimeter rock grows progressively larger. Data on perimeter rock displacement were collected along the upper disk's boundary within the mining field, yielding displacement curves for different scenarios.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003e exhibits the displacement curves of the perimeter rock in the upper section of the mining site:\u003c/p\u003e \u003cp\u003e(1) There were two significant increases in perimeter rock displacement in the upper part of the stope among various scenarios. The first occurred between the full-jointed top backfill and partial-jointed top backfill, while the second was observed between the partial-jointed top and no-jointed top backfill scheme. This underscores the substantial impact of stope backfill on reducing upper disk displacement.\u003c/p\u003e \u003cp\u003e(2) In the vertical direction, perimeter rock displacement gradually increases as one moves away from the working face, reaching its maximum near the top of the middle section and gradually decreasing further upward. The disparity in perimeter rock displacement among different backfill schemes primarily lies in the area away from the bottom working face.\u003c/p\u003e \u003cp\u003e(3) Within the 10\u0026thinsp;~\u0026thinsp;12m range from the mining operation face at the bottom of this middle section, there is no noticeable difference in upper disk perimeter rock displacement between different scenarios. The values and development trends of perimeter rock displacement remain consistent.\u003c/p\u003e \u003cp\u003eThese observations suggest that the displacement of the surrounding rock near the mining face is minimally affected by the backfill process during ore body mining [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], which may be attributed to the much greater stiffness of the surrounding rock compared to the backfill, with the backfill mainly improving stress conditions, maintaining surrounding rock integrity, and retarding displacement.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eA comparative analysis of four scenarios involving two-step unjointed top backfill in the downward approach yields the following conclusions:\u003c/p\u003e \u003cp\u003e(1) In line with the maximum principal stress analysis, backfill serves to enhance the structural integrity of the stope perimeter rock and maintain its stability. Nonetheless, the backfill's capacity to bear stress transfer is notably limited due to its low stiffness. It cannot fully absorb the entire stress transfer. Blindly augmenting both the backfill volume and backfill strength may fail to harness the natural load-bearing capacity of the perimeter rock, potentially leading to an excessive safety factor within the stope. This could result in substantial economic costs.\u003c/p\u003e \u003cp\u003e(2) Compressive stress experienced by the artificial false roof in various schemes remains below its compressive strength of 4 MPa. Generally, the internal stress in the lower part of the middle section of the stope's artificial false roof is modest, hovering around 2 MPa\u0026mdash;well within the backfill's compressive strength threshold.\u003c/p\u003e \u003cp\u003e(3) Displacement analysis indicates that within the 10\u0026thinsp;~\u0026thinsp;12m range above the mining face, the stope's perimeter rock is minimally affected by the spatial constraints of the excavation surface, resulting in negligible displacement. Consequently, deformation pressure exerted on the backfill remains low. Furthermore, initial displacement levels of the surrounding rock remain consistent across different backfill programs, indicating that the backfill's impact on surrounding rock deformation is insignificant.\u003c/p\u003e \u003cp\u003e(4) By comparing the magnitude and trends of stress displacement among various backfill schemes, it becomes evident that, within the 10\u0026thinsp;~\u0026thinsp;12m vicinity near the mining face in the middle section of the stope, stress displacement exhibits little variation among different schemes. Consequently, the stability of the backfill should be similar within this region. As a result, a field test may be considered for the every-three-fills-one backfill scheme. Conversely, stress displacement in the upper part of the stope surpasses that of the full roof backfill scheme, indicating higher safety risks and rendering it unsuitable for use.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThe present study was financially supported by the Natural Science Foundation of Hunan Province (2023JJ40546), and the Research Project of Education Department of Hunan Province (21A0264).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eYu Yin and Yan He wrote the main manuscript text;Shijiao Yang and Jian Pan designed the methodology and completed the data curation for this manuscript;Zhenpeng Guo, Junwei Fan, and Zhipeng Wang prepared figures 1-13 in this manuscript;All authors reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eData availability statement\u003c/h2\u003e \u003cp\u003eThe datasets used and/or analyzed during the current study available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eEmad, M.Z., 2017. 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Sustainability. 11 (2), 478. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3390/su11020478\u003c/span\u003e\u003cspan address=\"10.3390/su11020478\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Backfill mining, Slab-wall structure, Numerical simulation, Ground pressure, Stability analysis","lastPublishedDoi":"10.21203/rs.3.rs-3774525/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3774525/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eCharacteristic of ground pressure in surrounding rock is generally considered as the theoretical basis of parameter optimization for stope structure and technology. To explore the feasibility of efficient method for the second-step downward route backfill stopes in Shanjin gold mine, various numerical simulation methods were used to investigate the effect of slab-wall backfill structure on stability of surrounding rock in downward route mining system. The maximum principal stress, artificial false roof stress, and displacement were analyzed to evaluate the level of ground pressure in different mining areas. These results indicate the optimized structural parameters for backfill stopes, which may also provide a low-cost way to achieve a high safety for downward route mining system.\u003c/p\u003e","manuscriptTitle":"Stability assessment of surrounding rock in downward mining route supported by slab-wall backfill structure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-12-27 05:53:20","doi":"10.21203/rs.3.rs-3774525/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-03-21T06:58:42+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-02-05T08:31:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"50eeaeed-c053-4489-8334-99bb4ad1a731","date":"2024-02-04T17:59:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-02-04T17:56:23+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-02-04T14:38:34+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2023-12-21T18:22:41+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-12-21T18:18:46+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2023-12-19T02:42:43+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7b139aaf-23e3-494e-a61f-8f88e2eecddd","owner":[],"postedDate":"December 27th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":27772712,"name":"Earth and environmental sciences/Solid earth sciences"},{"id":27772713,"name":"Health sciences/Risk factors"},{"id":27772714,"name":"Physical sciences/Engineering"}],"tags":[],"updatedAt":"2024-06-21T15:39:50+00:00","versionOfRecord":{"articleIdentity":"rs-3774525","link":"https://doi.org/10.1038/s41598-024-64620-5","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2024-06-14 15:39:50","publishedOnDateReadable":"June 14th, 2024"},"versionCreatedAt":"2023-12-27 05:53:20","video":"","vorDoi":"10.1038/s41598-024-64620-5","vorDoiUrl":"https://doi.org/10.1038/s41598-024-64620-5","workflowStages":[]},"version":"v1","identity":"rs-3774525","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3774525","identity":"rs-3774525","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}