Geostress Conditions Research Articles

Hydropower Station diversion tunnel layered excavation deformation mechanism under high crustal stress

Aiming at the crucial engineering challenge of the ambiguous excavation deformation mechanism of hard and brittle surrounding rock under high geos-tress conditions, with the right bank diversion tunnel at the dam site of the hydropower station as the research object, the deformation and failure characteristics of the surrounding rock and their formation mechanisms during the layered excavation of the diversion tunnel were investigated. The research findings show: (1) The main factors influencing the deformation of the diversion tunnel’s surrounding rock are the high ground stress environment, the degree of fracture development in the rock mass, and the effectiveness of the support system. (2) Following the excavation of the first layer, extensive shallow damage predominates, with damaged blocks primarily exhibiting sheet-like and plate-like forms. After excavating the second and third layers, there is a significant reduction in confining pressure in this region, leading to a rapid deterioration in the extent of damage. (3) Layered excavation induces ‘time-dependent’ variations in the yield characteristics of the surrounding rock, while simultaneously being influenced by the location and extent of fracture development. The study results are expected to provide a theoretical basis for the excavation of underground caverns under high ground stress.

Research on dust and rockburst control technology for coal mining and mathematical correlation

As many coal mines in China enter the deep mining stage, underground mining is starting to cause some problems, including dust disasters, rockburst, and coal and gas outburst in enclosed sites. In this study, water injection tests were conducted on coal samples using a coal rock multi-field seepage simulation experimental system under geo-stress conditions. Experimental results demonstrate that, as the cycle period increases, permeability exhibits a gradual increase. Areas with high permeability change rates are predominantly observed at the beginning and end of the cycle. The relationship between permeability and the number of cycles is initially linear during the early and middle cycles. However, beyond 30 cycles, the relationship transitions from linear to nonlinear, indicating an accelerated permeability change after a certain cycle threshold. In conclusion, this study addressed and refined the mathematical relationship between volumetric strain and permeability. The findings of this research have significant implications for the prevention of dust emissions and the mitigation of rockburst disasters in the field.

Deformation and Stress of Rock Masses Surrounding a Tunnel Shaft Considering Seepage and Hard Brittleness Damage

The mechanical and deformation behaviors of the surrounding rock play a crucial role in the structural safety and stability of tunnel shafts. During drilling and blasting construction, seepage failure and hard brittleness damage of the surrounding rock occur frequently. However, previous discussions on stress deformation in the surrounding rock did not consider these two factors. This paper adopts the theory of elastoplastic to analyze the effects of seepage and hard brittleness damage on the stress and deformation of the surrounding rock of a tunnel shaft. The seepage effect is equivalent to the volumetric force, and a mechanical model of the surrounding rock considering seepage and hard brittleness damage was established. An elastoplastic analytical formula for surrounding rock was derived, and its rationality was verified through numerical examples. Based on these findings, this study revealed the plastic zone as well as stress and deformation laws governing the behavior of surrounding rock. The results showed that the radius of a plastic zone had a significant increase under high geostress conditions, considering the hard brittleness damage characteristics of the surrounding rock. The radius of the plastic zone increased with an increase in the initial water pressure and pore pressure coefficient, and the radius of the plastic zone increased by 5.5% and 3.8% for each 0.2 MPa increase in initial water pressure and 0.2 increase in pore pressure coefficient, respectively. Comparing the significant effects of various factors on the radius of the plastic zone, the effect of support resistance inhibition was the most significant, the effect of the seepage parameter promotion was the second, and the effect of the hard brittleness index promotion was relatively poor. The hard brittleness index and water pressure parameters were positively correlated with the tangential and radial stresses in the surrounding rock, and the radial stresses were overall smaller than the tangential stresses. The deformation of the surrounding rock was twice as large as the initial one when hard brittleness damage and seepage acted together. These findings can provide a reference for the stability evaluation of the surrounding rock in tunnel shafts.

Viscoelastic plastic interaction of tunnel support and strain-softening rock mass considering longitudinal effect

A simplified two-stage method was employed to provide an explicit solution for the time-dependent tunnel-rock interaction, considering the generalized Zhang-Zhu strength criterion. Additionally, a simplified mechanical model of the yielding support structure was established. The tunnel excavation is simplified to a two-stage process: the first stage is affected by the longitudinal effect, while the second stage is affected by rheological behavior. Two cases are considered: one is that the rigid support is constructed during the first stage, and the other is that constructed at the second stage. Distinguished by the support timing at the seconde stage, different kinds of the “yield-resist combination” support method are divided into three categories: “yield before resist” support, “yield-resist” support, and “control-yield-resist” support. Results show that the support reaction of “control-yield-resist” is much higher than that of “yield before resist” if the initial geostress is not very high, but the effect is not obvious on controlling the surrounding rock deformation. So, the “yield before resist” support is much more economical and practical when the ground stress is not very high. However, under high geostress condition, through applying relatively high support reaction actively to surrounding rock at the first stage, the “control-yield-resist” support is superior in controlling the deformation rate of surrounding rock. Therefore, in the high geostress environment, it is recommended to construct prestressed yielding anchor immediately after excavation, and then construct rigid support after the surrounding rock deformation reaches the predetermined deformation.

Experimental study on the mechanical characteristics of NPR anchored rock under kilometer-deep buried high geostress conditions

In this paper, a biaxial compression experimental study of NPR (Negative Poisson's Ratio) and PR (Poisson's Ratio) anchored rock under different burial depth conditions was conducted around a new type of constant resistance large deformation anchor cable, also known as NPR anchor cable. A comparative analysis was performed on mechanical characteristics of the two types of anchored rock. Furthermore, a concept of static toughness for anchored rock was established to evaluate the comprehensive mechanical performance. The results indicate that with increasing confining pressure, the elastic modulus of both types of anchored rock exhibits a gradual increase. The peak strength and residual strength initially decrease and then increase. The NPR anchored rock has higher elastic modulus, peak strength, and residual strength compared to PR, with increases of 17.5%, 26%, and 25%, respectively. As the confining pressure increases, the fine and short shear cracks within the lateral surfaces of the two types of anchored rock transform into wider and longer cracks. The final integrity of the NPR anchored rock is demonstrably superior to that of the PR. Compared to PR, the cumulative energy, cumulative count, and energy value per unit count of the NPR anchored rock throughout the experiment are significantly lower values. A calculated analysis revealed that the static toughness of the NPR anchored rock is considerably greater than that of PR.

Roof collapse mechanism of weak surrounding rock for deep-buried tunnels under high geostress conditions

Roof collapse mechanism of weak surrounding rock for deep-buried tunnels under high geostress conditions

Large-scale model test and numerical analysis of load-bearing arch characteristics of large cross-section tunnel under high geostress

Understanding the failure process and the load-bearing arch effect of the surrounding rock is crucial for the stability control and support design of tunnels under high geostresses. In this study, the progressive collapse behavior and the formation mechanism of the load-bearing arch of a soft rock tunnel under high geostress were investigated by a model test and numerical simulations. First, a large-scale model test was conducted to study the stress redistribution rules and the failure process of the soft rock under different overloads. According to the model test results, the formation of the final load-bearing arch was divided into four stages including initial local load-bearing arch formation, rock failure inside the local arch, overall load-bearing arch formation and load-bearing arch outward transition. Both the progressive failure and arch mechanism were related to the stress transfer effect. Then, numerical simulations were carried out to verify the stress response results from the model test. The determination method for the inner and outer boundaries of the load-bearing arch was put forward based on the circumferential stress distribution, which was validated by the model test results. Furthermore, the relationship between the radial displacement of the tunnel boundary and the arch position was illustrated. It was found that the load-bearing arch showed an oval shape with a big top and a small bottom. The arch position was linearly correlated with the radial displacement at the tunnel wall. This study provides a comprehensive understanding of the load-bearing arch characteristics of large cross-section tunnels in soft rocks under high geostress conditions, which can be referred to in construction control and support design during tunnel construction.

Research on stress field inversion and large deformation level determination of super deep buried soft rock tunnel

Understanding the characteristics and distribution patterns of the initial geo-stress field in tunnels is of great significance for studying the problem of large deformation of tunnels under high geo-stress conditions. This article proposes a ground stress field inversion method and large deformation level determination based on the GS-XGBoost algorithm and the Haba Snow Mountain Tunnel of the Lixiang Railway. Firstly, the hydraulic fracturing method is used to conduct on-site testing of tunnel ground stress and obtain tunnel ground stress data. Then, a three-dimensional model of the Haba Snow Mountain Tunnel will be established, and it will be combined with the GS-XGBoost regression algorithm model to obtain the optimal boundary conditions of the model. Finally, the optimal boundary condition parameters are substituted into the three-dimensional finite-difference calculation model for stress calculation, and the distribution of the in-situ stress field of the entire calculation model is obtained. Finally, the level of large deformation of the Haba Snow Mountain Tunnel will be determined. The results show that the ground stress of the tunnel increases with the increase of burial depth, with the maximum horizontal principal stress of 38.03 MPa and the minimum horizontal principal stress of 26.07 MPa. The Haba Snow Mountain Tunnel has large deformation problems of levels I, II, III, and IV. Level III and IV large deformations are generally accompanied by higher ground stress (above 28 MPa) and smaller surrounding rock strength. The distribution of surrounding rock strength along the tunnel axis shows a clear "W" shape, opposite to the surface elevation "M" shape. It is inferred that the mountain may be affected by geological structures on both sides of the north and south, causing more severe compression of the tunnel surrounding rock at the peak.

Effects of Geo-Stress and Natural Fracture Strength on Hydraulic Fracture Propagation in a Deep Fractured Tight Sandstone Reservoir.

Hydraulic fracturing technology has been widely used in the tight reservoir reconstruction. Unfortunately, with the deepening of mining depth and the increase of geo-stress, the propagation mechanism of medium-pressure fractures in the reservoir is significantly different from that of conventional shallow reservoirs. Based on the combined finite discrete element method, this paper conducts numerical simulation research on deep tight sandstone reservoirs in the west. The discrete fracture network modeling method is used to establish a tight sandstone reservoir model with natural bedding, and the influence of geo-stress difference and natural fracture strength on hydraulic fracture propagation law in a high geo-stress environment is discussed in detail. The results show that the difference between geo-stress and the strength of natural fractures has a significant effect on the shape and expansion of hydraulic fractures under the high geo-stress conditions. The greater the difference in ground stress, the more obvious the tendency of the main fractures of the reservoir, and the shorter the branch fractures. With the increase of natural fracture strength, the changes in propagation pressure, fracture length, area, and width, which can be fitted with a linear function with a goodness of fit as high as 0.99. In addition, the morphological results of hydraulic fractures in the simulation are not only affected by the constitutive parameters of the model but also may be affected by the randomness of the natural fracture network, thus, showing a certain degree of dispersion. Therefore, it is extremely necessary to build a reservoir fracturing model in a specific area based on more detailed geological monitoring data to guide actual construction. The above achievements have certain reference significance for the field operation of deep tight sandstone reservoirs.

Numerical Simulation of Rock Breaking by Diamond Particles Under Ultra Deep Drilling Conditions

In the quest to access deeper fossil energy reserves, the past three decades have witnessed a concerted effort by scientists to develop and refine technologies capable of efficient drilling in environments characterized by high temperatures and pressures. Despite these advancements, our comprehension of the physical phenomena at play remains incomplete. A fundamental challenge pertains to the interaction between the rock and the drilling bit during drilling operations. This study delves into the influence of drilling bit pressure and rotation speed on the rock-breaking efficacy of impregnated diamonds under geostress conditions of 240 MPa and temperatures of 200℃.It juxtaposes these findings with those from rock-bit interaction experiments executed on a physical simulator, which was designed in accordance with similarity principles, in a controlled laboratory setting. Our findings indicate that for ultra-deep formations, a high Weight on Bit (WOB) coupled with a lower rotation speed results in enhanced rock cutting efficiency and a reduced rate of bit wear. Consequently, we recommend optimal drilling parameters of 8.0 to 8.5 kN for WOB and a rotational speed range of 180 to 240 rad/min. Furthermore, the study underscores the profound impact of horizontal differential stress on the rate of penetration (ROP). The insights gleaned from these tests are instrumental in refining the design of rock-breaking tools and optimizing drilling parameters, thereby augmenting the efficiency of rock breaking in challenging drilling environments.

Seismogenic fault of the 2021 Ms 6.0 Luxian induced earthquake in the Sichuan Basin, China constrained by high-resolution seismic reflection and dense seismic array

Accurate documentation of the location and geometry of seismogenic faults are critical for understanding strong seismicity and seismic hazard mitigation. A rising concern worldwide is induced seismicity caused by hydraulic fracturing, yet the geological characteristics and mechanisms of such seismogenic faults remain insufficiently understood. In particular, a first-order issue is whether the strong (M ≥ 5.0) induced earthquakes are caused directly by the slip of shallow faults near shale reservoirs or indirectly by deep basement faults. The September 16, 2021 Ms 6.0 (Mw 5.4) Luxian earthquake in the Sichuan Basin, China is one of the world's greatest induced earthquakes related to shale gas exploitation. Here we constrain the geometry of the seismogenic fault of this earthquake using three-dimensional seismic reflection data and a dense seismic array. Pre-existing faults in the sedimentary cover are clearly visible in seismic coherence slices. However, these shallow faults do not match the seismological parameters of the Luxian earthquake. High-resolution seismic reflection profiles combined with relocated earthquakes indicate that the seismogenic fault is located in the Precambrian basement. The results suggest that the mainshock is most likely caused by the poroelastic effects due to fluid injection. Hydraulic fracturing could have reactivated a large-scale basement fault and triggered the strong earthquakes under a relatively high geo-stress conditions in the study area. The basement fault slipped upward and ruptured the sedimentary cover, resulting in a significant difference between the focal and centroid depths of the mainshock. Our findings emphasize the importance of investigating regional tectonic and geological settings, local stress fields, and pre-existing faults for studying potential induced seismicity in shale gas fields.

Generalized Weighted Mahalanobis Distance Improved VIKOR Model for Rockburst Classification Evaluation

Rockbursts are hazardous phenomena of sudden and violent rock failure in deep underground excavations under high geostress conditions, which poses a serious threat to geotechnical engineering. The occurrence of rockbursts is influenced by a combination of factors. Therefore, it is necessary to find an efficient method to assess rockburst grades. In this paper, we propose a novel method that enhances the VIKOR method using a novel combination of weight and generalized weighted Mahalanobis distance. The combination weights of the evaluation indicators were calculated using game theory by combining subjective experience and objective data statistical characteristics. By introducing the generalized weighted Mahalanobis distance, the VIKOR method is improved to address the issues of inconsistent dimensions, different importance, and inconsistent correlation among indicators. The proposed method can deal with the complexity of the impact factors of rockburst evaluation and classify the rockburst intensity level. The results show that the accuracy of the improved VIKOR method with the distance formula is higher than that of the unimproved VIKOR method; the evaluation accuracy of the improved VIKOR method with the generalized weighted Mahalanobis distance is 91.67%, which outperforms the improved VIKOR methods with the Euclidean and Canberra distances. This assessment method can be easily implemented and does not depend on the discussion of the rockburst occurrence mechanism, making it widely applicable for engineering rockburst evaluation.

Rockburst Hazard Control Using the Excavation Compensation Method (ECM): A Case Study in the Qinling Water Conveyance Tunnel

Rockburst disasters occur frequently during deep underground excavation, yet traditional concepts and methods can hardly meet the requirements for support under high geo-stress conditions. Consequently, rockburst control remains challenging in the engineering field. In this study, the mechanism of excavation-induced rockburst was briefly described, and it was proposed to apply the excavation compensation method (ECM) to rockburst control. Moreover, a field test was carried out on the Qinling Water Conveyance Tunnel. The following beneficial findings were obtained: Excavation leads to changes in the engineering stress state of surrounding rock and results in the generation of excess energy ΔE, which is the fundamental cause of rockburst. The ECM, which aims to offset the deep excavation effect and lower the risk of rockburst, is an active support strategy based on high pre-stress compensation. The new negative Poisson’s ratio (NPR) bolt developed has the mechanical characteristics of high strength, high toughness, and impact resistance, serving as the material basis for the ECM. The field test results reveal that the ECM and the NPR bolt succeed in controlling rockburst disasters effectively. The research results are expected to provide guidance for rockburst support in deep underground projects such as Sichuan–Xizang Railway.

Investigation of casing stress distribution and parameter optimization during the transient impact process of multi-hole perforation operations

Perforation operation is critical in bridging completion and production enhancement operations. At the same time, the perforation parameters also affect the structural integrity of the casing. Still, there are fewer studies on the stress distribution of the casing under the blast transient impact loading of multi-hole perforation. To address this, considering the engineering application of helical perforation in unconventional oil and gas reservoirs, a three-dimensional numerical model of perforating charge-casing-cement sheath-formation is established, and the Holmquist-Johnson-Cook (HJC) rock dynamics material model, as well as the fluid–solid coupling and Arbitrary Lagrange-Euler (ALE) algorithms. On this basis, the variation rule and distribution characteristics of the effective stress in the double-perforation holes stress superposition area under different perforation density, phase angle, and geostress conditions are analyzed with the casing strength safety threshold as the optimization judgment condition of perforation parameters. The research results show that the numerical simulation result has good consistency in the results of engineering practice, perforation aperture diameter error is 3.04%, and jet head velocity error is 6.85%. The variation rule of perforation density and phase angle has a significant effect on the effective stress distribution in the stress superposition area around the hole: with the decreasing perforation density or increasing phase angle, the casing stress superposition area in the middle part of the neighboring perforation holes is gradually narrowed down, and when the perforation density is more than 9 P/m and 51°, the casing stress in the stress superposition area between the perforated holes is lower than the safety threshold value. With the increasing ground stress, the stress in the middle of the neighboring perforated holes increases continuously, showing a quadratic function change trend. The perforation density should be appropriately reduced, and the phase angle should be increased when the geostress is high to ensure the integrity of the casing structure after the perforation operation. The research results can provide a practical reference for conducting perforation engineering operations and optimizing perforation parameters.

Numerical modelling and field observations on the failure mechanisms of deep tunnels in layered surrounding rock

Tunnelling through layered rock mass with high geo-stress often leads to large deformation disasters, including rock collapses and structural failures. This study investigates the asymmetrical deformation and failure behaviors of deep tunnels in layered phyllite strata in Chengdu-Lanzhou railway (China). It has been observed that the mechanical behavior of these tunnels exhibits evident correlations with the orientations between geo-stress conditions and bedding plane. For in-depth analysis, a modeling method was first proposed considering the difference between interlayer bedding planes and intralayer joints. The excavation disturbance behaviors of unsupported tunnels with various bedding angles, such as deformation characteristics, crack generation and propagation, and stress distribution, were simulated and compared with on-site phenomena. Afterward, the crack distributions were classified into four typical types based on simulation results, and their causes, differences, characteristics, and evolutionary process mechanisms were also systematically analyzed. Additionally, the asymmetric failure caused by the weak plane effect was investigated and discussed. The results revealed that the bedding angle, the direction of principal stress and the effect of layer thickness primarily influenced the failure patterns of layered surrounding rock, which resulted in variations in both the direction and depth of failure. Engineering practice demonstrated that the classification method, based on the proposed numerical modeling approach, can serve as a valuable reference for tunnel support design.

STUDY OF SAND PRODUCTION STAGES IN SHALLOW OIL FIELDS

This article presents the High Pressure Consolidation System (HPСS) and a new experimental method for studying sand behavior in weak sandstone reservoirs. Under laboratory conditions, geostress conditions during the process of rock sedimentation, perforation, and sand production were replicated using a large artificial sample. A comprehensive investigation of sand production phenomena was conducted, where rock and pore pressures were fully controlled throughout the experiment using a computer. The HPCS also allows the study of single-phase and multiphase flow behavior in porous media at realistic reservoir pressures to model various well exploitation scenarios, such as implementing different depletion factors and water-oil ratios.

Numerical Simulation Method for Tunnel Excavation Considering Mechanical Characteristic Variation of Soft Rock with the Confining Pressure Influence

The accurate prediction and evaluation of stress and displacement fields of surrounding rock is the fundamental premise for the deformation control of soft rock tunnels under high geo-stress condition. However, due to the complicated mechanical characteristics of soft rock with confining pressure influence, the current numerical simulation method usually regards the mechanical parameters of surrounding rock as constant and ignores the variation of these parameters in the simulation process, which leads to results that cannot accurately reflect the mechanical behavior of surrounding rock. Therefore, this paper firstly investigates the effect of confining pressure on deformation and strength parameters for soft rock and proposes corresponding variable models for mechanical parameters with the confining pressure influence. Secondly, a transversal loop discriminant update procedure is proposed and introduced into the iteration calculation process of FLAC3D, thus forming an improved numerical simulation method. This improved method can integrally consider the mechanical parameter variation of surrounding rock with variable confining pressure and realize the automatic update for such a parameter with its variable stress state. Finally, as an application example, an improved expression of longitudinal deformation profile (LDP) for tunnels considering the confining pressure influence is proposed based on numerous simulation results for a soft rock tunnel obtained by this proposed method.

Numerical investigation of geostress influence on the grouting reinforcement effectiveness of tunnel surrounding rock mass in fault fracture zones

Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones, and its reinforcement effectiveness is highly affected by geostress. In this study, a numerical manifold method (NMM) based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation. To develop this simulator, a detection technique for identifying slurry migration channels and an improved fluid-solid coupling (F–S) framework, which considers the influence of fracture properties and geostress states, is developed and incorporated into a zero-thickness cohesive element (ZE) based NMM (Co-NMM) for simulating tunnel excavation. Additionally, to simulate coagulation of injected slurry, a bonding repair algorithm is further proposed based on the ZE model. To verify the accuracy of the proposed simulator, a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced, and the results align well with analytical and laboratory test results. Furthermore, these numerical results show that neglecting the influence of geostress condition can lead to a serious overestimation of slurry migration range and reinforcement effectiveness. After validations, a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted. Based on these simulations, the influence of geostress conditions and the optimization of grouting schemes are discussed.

The Damage Induced by Blasting Excavation and Seepage Characteristics of Deep Rock under High Seepage Pressure

By taking the blasting excavation of a deeply buried karst tunnel in the North Tianshan Mountains in China as research objects, the damage induced by blasting excavation and seepage characteristics of deep rock under high seepage pressure was investigated. The COMSOL Multiphysics® software was adopted to establish a simulation model for the blasting excavation of a deeply buried tunnel. By embedding the stress-damage-seepage multifield coupled constitutive relationship, the mechanism of the influences of factors including blasting load, geostress, and hydraulic pressure of karst caves on the blasting excavation-induced damage to, and seepage characteristic of, the surrounding rocks of the tunnel. The results indicate that blasting excavation in the karst tunnel triggers the damage of surrounding rocks, which consists of blasting-induced damage and unloading damage. The time-history curve of the variable for surrounding rock damage rises and consequently tends to a constant value. With the increases in blasting load, geostress, and hydraulic pressure of karst caves, the degree of damage to surrounding rocks is intensified; an increase in geostress will weaken the effect of blasting-induced damage to rock while increasing rock damage arising from unloading. Meanwhile, the degree of damage to the surrounding rock can affect the seepage velocity of water in the surrounding rock to a certain extent. A strong damage and seepage coupled effect occur in the blasting excavation process of the karst tunnel. The such coupled effect is strengthened little by little with the increases in the degree of surrounding rock damage and hydraulic pressures. The results are expected to provide theoretical guidance for hazard prevention and control of blasting excavation in karst tunnels under high geostress conditions.

Damage Assessment of Roadway Wall Caused by Dynamic and Static Load Action of Gas Explosion

In order to obtain the damage characteristics of a roadway wall caused by a gas explosion, the damage evaluation theory of a roadway wall under the dynamic and static loads of a gas explosion is analyzed in this paper. Meanwhile, an evaluation method (overpressure–impulse criterion) is selected to evaluate the damage of the roadway wall under the impact load of the gas explosion. A mathematical model and a physical analysis model of the roadway wall damage are established by LS-DYNA software. The dynamic response of the roadway wall caused by the dynamic and static loads of the gas explosion is numerically simulated. The overpressure and impulse of gas explosion propagation are measured, while the damage data of the roadway wall under different overpressure and impulse loads are obtained. The P-I curves of the roadway wall under different dynamic and static loads of gas explosion are drawn. The fitting formula of P-I curves of the roadway wall is obtained. The influence of different geostress loads (0–20 MPa) on the P-I curve is analyzed. The shape of the P-I curve is similar under different geostress conditions. The difference is mainly shown in different sizes of P0 and I0. The numerical simulation results show that the P-I curve and the effect of geostress on roadway wall damage could reflect the dynamic response of the roadway wall. The damage degree and damage range of the roadway wall increase with the increase in explosion load energy. Under the action of different geostresses, the overpressure asymptote P0 and the impulse asymptote I0 show linear changes. The above research results could provide a theoretical basis and data support for the evaluation of roadway wall damage caused by gas explosions.