Open-off Cut Research Articles

Evolution Laws of Water-Flowing Fracture Zone and Mine Pressure in Mining Shallow-Buried, Hard, and Extra-Thick Coal Seams

Shallow-buried, hard, and extra-thick coal seams are very common in Xinjiang, China, but there are relatively few studies on the mine pressure law and the development characteristics of water-flowing fracture zones (WFFZs) during the mining of such coal seams. In this paper, the mine pressure of the top coal caving face in a shallow, hard coal seam with a hard roof and full bedrock (SHCSHRFB) is analysed, the laws of the surrounding rock deformation and stress of the open-off cut and roadway in the large-mining-height top coal caving face are studied, the characteristics of roof-breaking and overburden fracture development are analysed using the physical similarity simulation method, supporting suggestions for roadways are put forward, and three development stages of the WFFZ are analysed. Field monitoring shows that the hydraulic support stress in SHCSHRFB is weak, but the coal wall and roadway stability are good, which is significantly different from the results in the typical shallow-buried thin bedrock working faces. The measured height of the WFFZ is close to the physical similarity simulation results, but quite different from those arising from use of the empirical formula.

Reasonable top coal thickness for large cross-section open-off cut in lower-layer mining

The thickness of top coal is the main factor affecting the stability of the large cross section open-off cut under the goaf. The 1-2 lower 203 cross section open-off cut of the Huojitu Coal Mine was used as the background to investigate the top coal rational thickness of the large cross section open-off cut under the goaf in slicing mining. The top coal above the cut was simplified into a beam model to calculate its plastic zone range with the elastoplastic theory under the influence of the upper slicing mining and the lower slicing cut excavating. The deformation law of the top coal of the large cross section open-off cut under different top coal thicknesses was studied with both a simulation experiment and numerical simulation. The displacement, stress, and top coal structure of the surrounding rock of the cut were observed in situ using several observation methods. The results show that the plastic zone of the floor in the upper slicing face and the influence of the cut excavation are 2.02 m and 1.43 m, and the maximum plastic zone of the top coal is 3.45 m. A top coal thickness of more than 3.45 m is conducive to maintaining the stability of the large cross section open-off cut. The top coal of the cut can be divided into the roof-fall hazard zone and roof-fall warning zone according to the results monitored by distributed optical fiber. When the top coal thickness is 3.0 m, 3.5 m, and 4.0 m, the deformation law changes from an exponential deformation to a linear and then to a logarithmic relationship in the roof-fall hazard zone and from a linear to a logarithmic relationship in the roof-fall warning zone. When the thickness of top coal is 3.5 m and 4.0 m, the subsidence trend of the top coal visibly decreases, and the subsidence is only 56% and 39% of the subsidence of that of a thickness of 3 m. The deformation law of top coal measured using the DIC (Digital Image Correlation, DIC) is consistent with that of distributed optical fiber. The average thickness of the top coal reserved in the 1-2 lower 203 large cross section open-off cut is 4.0 m. The maximum surface subsidence of the top coal cut hole is 12 mm in the field monitoring. The maximum internal subsidence is 6 mm, and the maximum shed beam strain is –416 με. The deformation of the top coal is slight, indicating that the top coal thickness of 3.5–4.0 m is reasonable.

Study on Active Support Parameters for Surrounding Rock with Ultra-Large Span Open-Off Cut in Thick Coal Seam

In order to effectively control the stability of surrounding rock in ultra-large span open-off cuts by employing the techniques of support strength theory calculations and analogical application methods, two sets of rational support schemes were proposed, and the optimal design of active support parameters in thick coal seams with ultra-large span open-off cuts was explored by using theoretical analysis, numerical simulation, and field experiments. The results demonstrated that the span is one of the key factors influencing the stability of the roadway roof, exhibiting an inverse quadratic relationship with the peak stress borne by the roadway roof. By utilizing the pre-stressing force of anchor cables and support strength formulas, two sets of active support schemes for controlling the surrounding rock in thick coal seams with ultra-large span open-off cuts were established, and an optimized support scheme was obtained through numerical simulation. These findings provide references and guidance for related mining engineering under actual conditions in mines.

Rule Study on the Risk of Floor Water Inrush Based on the Plate Model Theory

In order to mitigate the potential issue of abrupt water inrush in coal mining operations, the elastic-plastic mechanics theory was employed to simplify the water barrier of the floor strata into a thin rectangular plate. Subsequently, a fluid-solid coupling damage model was designed through the utilization of COMSOL Multiphysics software to investigate the coupled seepage and damage effects of the rock mass in an equivalent continuous medium. The results indicate that (1) the analysis of the theoretical equation of elastic mechanics shows that the fracture position of the four-sided clamped thin plate is in the center of the four sides, and the theoretical limit span and the theoretical limit water pressure formula are derived. (2) The damage factor is used to characterize the damaging effect of different mining distances and different pore water pressures on the rock mass of the floor aquiclude in the numerical simulation. It is found that the damage tends to the open-off cut and stop-mining line of the floor waterproof layer and the center position on both sides of the coal wall, and the stress is the most concentrated. (3) The results obtained by the two research methods are highly consistent, which provides a theoretical basis for the prevention and control of water in ground mining mines, so as to realize safe mining above the confined aquifer.

Multistage cooling system for temperature reduction of the working face in deep coal mines: A technical-economic evaluation

Workers in deep coal mines are often exposed to hyperthermal conditions, which is a health and safety hazard. Although many novel approaches have been proposed in recent years, air distribution optimization combined with thermal analysis based on existing cooling systems has rarely been conducted. Here, heat dissipation in the deep mine environment was estimated based on field measurements and numerical simulations. A pilot study was conducted to validate the performance of the multistage cooling system and optimize the distribution ventilation. The results show that the “2 + 3” layout (Two air cooler outlets are in the machine lane, and three air cooler outlets are in the open-off cut) was superior to other schemes in terms of the temperature field and energy consumption. In addition, the outlet air temperature should be set to ≤20 °C, and the air volumetric flowrate of the longest outlet should be > 400 m3/min to improve the thermal environment of the wind lane. This effectively reduces the average temperature of the entire working face by 4.6–5.1 °C compared to the situation without cooling measures, thereby increasing the comfortable zone of the working face (<30 °C) by 83–86%.

Movement and deformation characteristics of overlying stratum in paste composite filling stope

Paste composite filling mining is one of the effective ways to realize green mining. In order to study the movement and deformation characteristics of overlying stratum in paste composite filling stope, taking the test mine as the engineering background, a mechanical model of movement and deformation of roof rock beam in paste composite filling mining was established by combining theoretical analysis, physical simulation and numerical simulation. The movement and deformation laws of main roof, sub-key stratum and main key stratum in the process of working face advancing under the conditions of multiple factors (mining height, filling ratio and buried depth) were analyzed. The results show that the displacement contour of overlying stratum is inverted trapezoid in the process of advancing working face which is unfilling or filling 2/3. The subsidence of stratum near the coal seam is larger, and the subsidence of stratum with higher distance from the coal seam is smaller, and the maximum subsidence point of overlying rock appears near the side of the open-off cut. With the increase of mining height, the range of overlying rock caving zone becomes larger, and the maximum subsidence value gradually increases. When the paste filling ratio of the working face increases, the collapse range of the roof decreases, the overall compression of the collapsed rock decreases, and the effect of control on the movement and deformation of the overlying rock is obvious. The subsidence of overlying stratum increases with the increase of buried depth of working face, but it does not change much. The deflection value of the roof rock beam changes slowly at both ends of the propulsion due to the support of the coal wall. The closer to the middle, the greater the change. The results of this study can provide an important reference for the control of the roof stability and surface subsidence of the paste composite filling mining.

Study on Key Parameter Design and Adaptability Technology of the 110 Mining Method for the Yuwang NO.1 Coal Mine in the Diandong Mining Area

The 110 mining method is a high-efficiency entry-retaining technology without coal pillars or filling materials. At present, there is no precedent for its application in the Huaneng Group. In order to introduce this technology, it is planned to carry out experimental application research in the Yuwang NO.1 Coal Mine of the Huaneng Diandong mining area. The Yuwang NO.1 Coal Mine is a typical coal and gas outburst mine with a coal seam group. In view of the introduction of the 110 mining method under these conditions, first, the geological conditions of the Yuwang NO.1 Coal Mine in the Huaneng Diandong mining area are analyzed, the geological characteristics of the test mining face are summarized, and the practical feasibility of the 110 mining method is analyzed according to the geological characteristics of “one soft, one low, two high, and two complex”. Then, according to the engineering experience, calculations, and analysis, the key parameters of roof cutting of the test mining face in the Yuwang NO.1 Coal Mine are obtained, and with the help of a numerical simulation, the roof-cutting height, the roof-cutting angle, and the blasting parameters are numerically simulated and analyzed. The roof-cutting key parameters of the test face are obtained as follows: the roof-cutting depth is 7 m, the roof-cutting angle is 15°, and the blasting method is continuous hole blasting with 500 mm spacing. After that, according to the coal and gas outburst and the occurrence conditions of coal seams in the Yuwang NO.1 Coal Mine, a variety of gob closure design schemes and gob gas drainage design schemes are put forward, and the field effect investigation scheme is given. After the tunnels and open-off cut of the test coal mine’s first mining face are connected, under the guidance of the above research results, the field blasting test and the 110 mining method entry-retaining test are further carried out to verify the rationality of the design of the roof-cutting parameters and the feasibility of the gangue wall closure and gas drainage design. Furthermore, in the process of the field practice, continuous research is carried out on the stope pressure law and the adjacent layer gas drainage technology under the 110 mining method, and finally, the 110 mining method application technology system in the Diandong Mining Area is formed.

Overburden Failure Associated with Slicing Mining in a Super Thick Coal Seam under Special Weak Aquifers

With the increasing improvement of national ecological standards, the eco-environmental problems caused by super thick coal seam mining in western China are becoming more and more serious. The failure law of weak overburden stratum is an important factor affecting the safe mining of coal. The failure characteristics of weakly cemented overburden under high-intensity mining in the mining area of western China were studied. For this purpose, a case study was conducted in the 1101 working face of the Baituyao Coal Mine in Ürümqi County. Based on the analysis of geological conditions in the study area, we combined empirical calculations with engineering analogy, physical simulation, and numerical simulation to comprehensively analyze the characteristics of mining-induced overburden failure. The study showed that the overburden in the study area had several unfavorable engineering geological characteristics, including ease of softening in the presence of water. The Middle Jurassic Xishanyao Formation is a directly recharged aquifer with a weak water-retaining property. Overburden failure mainly occurred at the two ends of the open-off cut. During the mining process, vertical fissures and bed-separated fissures were periodically developed and closed, and the fissures were interconnected. The overburden was fractured, and the fractured zone showed a trapezoidal shape, tapering off from bottom to top. The heights of the caving zone and the water-conducting fracture zone were 25 and 280 m, respectively, in the 1101 working face of the Baituyao Coal Mine, and the ratio of fracturing to mining height was 14.0. Due to the weakly cemented overburden and the presence of the Neogene weak aquifer, the risk of water and sand bursts still exists in this working face under high-intensity mining. Our findings shed light on the safe mining and environmental protection of the ground surface in coal mine shafts in western China.

Analysis of the top coal stability of the large section open-off cut under the gob in thick seams slicing mining

The reserved thickness of top coal has an important influence on the stability of a large section open-off cut under gob in the thick seams slicing mining. The destabilization extremum conditions of the open-off cut top coal were derived from by elastic–plastic theory, and the optical fibre sensing technology was utilized to monitor the top coal deformation law with different thicknesses (3, 3.5, and 4 m) in the physical similar simulation experiment in the paper. The results show that the top coal thickness is greater than 3.4 m without tension cracks. In the vertical direction, the top coal of the large open-off cut is divided into mining and excavation disturbance zones under the influence of the upper slice coal mining and the excavation disturbance. In the direction of the span of the top coal can be divided into the roof fall risk zone and the warning zone. The deformation changes from exponential to linear to logarithmic in the roof fall risk zone, and it changes from linear to logarithmic in the roof fall warning zone as the number of excavations increases. The sinking amount in the two zones is smaller as the thickness of the top coal becomes larger. It is comprehensively determined that the thickness of the top coal of open-off cut is set as 3.5 m, the stability is moderate, and the field application shows that the integrity of the top coal is good after support, and the maximum off-layer value is 6 mm, which can satisfy the production requirements.

Coal pore structure changes in upper protective seam after mining: Pingdingshan Shenma Group, Henan Province, China

Protective layer mining is a safe and effective method of gas control in coal mining; we should pay more attention to changes in the pore structure of coal in protected layers, but there is less research in this aspect. We analyzed the characteristics of different-size pores in coal samples affected and unaffected by a protective layer at a distance of 900 m from the open-off cut of the protected layer. The pore morphology, type, size, and distribution in the coal seams affected and unaffected by the protective layer were qualitatively studied via field-emission scanning electron microscopy. Mercury intrusion capillary pressure testing was applied to analyze differences in pores of the same size between coal seams affected and unaffected by the protective layer. Protective layer mining increases the pore sizes of irregular pores. The protective layer has a large effect on various pores at different distances from the open-off cut. Within 100–700 m of the open-off cut of the protected layer, the upper protective layer mining promotes the conversion of 1–10 μm pores to 8–200 μm pores. When the distance from the open-off cut is less than 100 m, the upper protective layer mining facilitates the transformation of 10–100-nm pores into 100 nm to 10 μm pores. At distances of 100–900 m from the open-off cut, the porosity of pores with sizes from 10 nm to 200 μm increases markedly (with a maximum increase of 14%). The results of this study provide a theoretical foundation for designing a protective layer, evaluating its effect, and the research of gas seepage law and gas emission.

Study on Failure Characteristics and Reasonable Mining Parameters of Upward Mining of Integrated Coal Mine

In order to avoid the problem of repeated repair of roadways in the upper mining area of upward mining in the integrated mine, taking the roadways in the 302 mining area of Shancheng Coal Mine as the research object, the failure characteristics of overlying strata and the evolution characteristics of roadway plastic zone in the mining process of underlying coal seam were studied by combining theoretical analysis, numerical simulation, and engineering measurement. The influence law of underlying coal seam mining on the integrity of 3# coal seam and the stability of roadways in the 302 mining area was revealed, and the repair opportunity of roadways in the upper coal seam and the reasonable position of open-off cut in the lower coal seam working face were determined. The research shows that due to the influence of the mining of the working face in the underlying coal seam, the plastic failure of the overlying strata is serious during the upward mining of Shancheng Coal Mine, but there is no step dislocation, but the overall subsidence is presented. The plastic zone range of roadway in 302 mining area first increases and then tends to be stable with the mining of 97308 working face in underlying coal seam, and the roadway repair should be carried out after 280 m advance of 97308 working face. Based on the coordination between the influence of the cutting position of the underlying coal seam on the variation characteristics of the plastic zone of the upper roadway and the saving of coal resources, it is determined that the cutting position of the underlying 153308 working face is advanced to 340 m. The field engineering application shows that the deformation of roadway surrounding rock meets the production requirements by implementing the above mining parameters, and the rerepair of roadway surrounding rock deformation in 302 mining area of 3# coal seam is avoided.

Spatio-Temporal Evolution Law of Surface Subsidence Basin with Insufficient Exploitation of Deep Coal Resources in Aeolian Sand Area of Western China

Coal is one of the fundamental fossil energy supporting the world’s economy. The synergistic development between efficient coal mining and ecological environment protection is the inevitable requirement for the preservation of global harmony. As the world’s largest coal producer, China has conducted a strategic shift from east to west in terms of the exploitation of its energy resources, posing a serious threat to the fragile ecological environment of the western region. In particular, the surface subsidence caused by coal mining is the root of the ecological deteriotation and the destruction of ground structures. However, it is difficult to reveal the law of large-scale surface subsidence in western mining areas merely by conventional measurement methods such as leveling, on account of the high intensity of coal seam mining, the weakness of the lithology of overlying rock and the large thickness of wind-blown sand strata. In view of this, small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technology was used in this study to obtain the time series of surface vertical displacement during the whole mining process of the 2401 working face in the Yingpanhao coal mine, Inner Mongolia. Based on the deformation data, the dynamic evolution characteristics of surface subsidence under high intensity mining in the western mining area were analyzed exhaustively. It was found that the surface subsidence is characterized by an extensive coverage range (48.52 km2) with minimal ground settlement (250 mm) in the study area. Meanwhile, the boundary shape of the subsidence basin followed a “circular-parallelogram-trapezoid” changeable process and the coverage area of the basin experienced three stages: a linear increasing period, a temporary stagnation period, and a re-expansion period. Furthermore, there existed an abnormal uplift phenomenon on the east side of the open-off cut in the 2401 working face. Combined with the structure of overlying strata, this paper carried out a preliminary analysis on the reasons of the abovementioned phenomenon. The research results are of vital realistic significance for ground buildings and ecological environmental protection in the aeolian sand mining area in Western China.

Study on the Overburden Failure Law of High-Intensity Mining in Gully Areas With Exposed Bedrock

Most hilly areas are dotted with gullies, some of which contain plenty of water, especially in rainy seasons. Once surface water penetrates the underground working face, it will lead to an increased water inflow of the working face. Even worse, it may induce water and sand burst accidents. To prevent geological disasters such as water and sand burst and ensure the safe production in coal mines, it is necessary to reveal the development law of “two zones” in the overburden caused by shallow-seam fully mechanized top coal caving high-intensity mining in hilly areas with exposed bedrock and timely grasp the communication between the water-flowing fractured zone (WFFZ) and the water in surface gullies. In this study, the working face P2 of the exposed bedrock surface in the Coal Mine DN is taken as the research object. First, the characteristics of overburden movement and the law of exposed bedrock surface movement in areas with exposed bedrock were investigated through similar simulation. Meanwhile, the temporal–spatial evolution of overburden movement caused by shallow-seam fully mechanized top coal caving high-intensity mining was clarified, and the mode of overburden movement was revealed. Moreover, the reason why the water inflow of the underground working face increases suddenly was theoretically explained. The following conclusions were drawn: Under shallow-seam fully mechanized top coal caving high-intensity mining, the WFFZ of the working face P2 is directly connected to the exposed bedrock surface, and the movement of the overburden is subject to the typical “two-zone” mode. The development height of the WFFZ is greater than the value in the traditional “three-zone” mode calculated according to the empirical formulas. The ratio of the WFFZ height to the mining thickness is 43.75. Under the “two-zone” mode, a water-flowing channel exists in the overburden near the open-off cut and the stopping line. When the surface water source is in the right position, the water inflow of the underground working face will increase suddenly.

Stability Analysis and Control Measures of Large-Span Open-Off Cut with Argillaceous Cemented Sandstone Layered Roof

This paper is based on the condition where layered argillaceous cemented sandstone as an engineering background is met by the No. 207 fully mechanized working face open-off cut (Wanli No. 1 Coal Mine). Through mechanical theory analysis and field practice, the engineering safety problem of the large-span argillaceous cemented sandstone layered open-off cut roof supporting structure was analyzed. The roof caving arch height of the open-off cut roadway in 207 working face was obtained based on the mechanical mechanism of instability and caving of the layered surrounding rock mass roof. The anchor cable suspension and bearing stability of the open-off cut roof were analyzed in terms of the layered beam structure model. Meanwhile, combining with conditions, reasonable and effective support countermeasures and key parameters are proposed for such open-off cut roadway and enhance the actual supporting engineering on-site. These research results could provide engineering reference for an open-off cut roadway with composite roof conditions featured to weak cementation and weak interlayer.

Distribution Characteristics and Formation Mechanism of Surface Crack Induced by Extrathick Near Horizontal Seam Mining: An Example from the Datong Coal Field, China

Under the mining condition of extrathick coal seam, the overburden moves violently, the surface is destroyed seriously, and the discontinuous deformation such as cracks is fully developed. Taking Datong mining area as an example, this paper studies and analyzes the development characteristics and generation mechanism of surface cracks in loose layer covered area and bedrock exposed area by means of field measurement and similar model experiment. In the bedrock exposed area, there is no main crack. The width, length, number, and step drop of surface cracks are relatively small. There are many cracks with the same scale and distributed evenly and parallel. However, in the loose covered area, the main cracks are mainly located above the open-off cut and the stoppage line side that is deviated from the working face. There are many secondary cracks around the main crack, with a large crack density and a few cracks in the outer edge of the main crack. Through research, it is found that three mining faces belong to the typical three-zone mining mode and the main fracture is consistent with the O-ring fracture distribution theory. This research’s results can provide theoretical and technical support for the follow-up land remediation and ecological restoration.

Research and Application of Open-Off Cut Roof Cutting Pressure Releasing Technology

The first weighting control is one of the difficult problems that cannot be avoided in the safe and efficient production of longwall mining face. To optimize the existing pressure releasing technology of open-off cut, the open-off cut roof cutting pressure releasing (OCRCPR) technology is put forward on the basis of roof cutting pressure releasing gob-side entry retaining (RCPRGER) technology. Firstly, the mechanism of the technology and the design method of related key parameters are summarized. Then the pressure releasing effect of OCRCPR and the stress environment change under this technology are analyzed by mechanics calculation and numerical simulation, respectively, which verify the feasibility of the OCRCPR technology from the theoretical level. Finally, a test mining face is taken as an example to implement the field test. The field test results show that the OCRCPR can effectively shorten the first weighting step and weaken the first weighting strength and has a good pressure releasing effect.

Theoretical and Numerical Investigations of the Failure Characteristics of a Faulted Coal Mine Floor Above a Confined Aquifer

Mechanical models were used to analyze the failure depth of faulted and faultless mine floors based on the limit equilibrium theory of rock mass. In addition, the failure characteristics and water-inrush pathways were numerically investigated. The results were then compared, along with in-situ observations to validate these models. The mining-induced failure zone (an asymmetric “inverted saddle” shape) near the mined-out area was larger in the floor strata beneath the area around the coalface than that near the open-off cut. The maximum fault-induced failure depth was approximately twice that of the intact floor, which was generally equivalent to the in-situ observations. Three characteristic zones in the floor strata were observed during the mining process in the numerical models: a mining-induced failure area, a water-impervious area, and a fault reactivation area. The formation of the failure zone can be roughly divided into an initial stage, a stable stage, and a mutation stage. This study provides an improved understanding for predicting fault-induced mine water-inrushes.

Study on Dynamic Evolution of Roof Crack and Support Timing of Secondary Tunneling for Large Section Open-Off Cut in Deep Mines

The stability of large section open-off cut in deep mines (LODM) is the key factor affecting the normal equipment installation and safe mining in fully mechanized top-coal caving face. The mechanical model shows that the deflection of the roof of the LODM is proportional to the cubic of span. In this paper, UDEC Trigon model is established, and the parameters of different coal measures strata are modified in detail. The evolution law, failure mode, and damage degree of roof cracks in secondary tunneling are studied, and the roof support effect is analyzed. The numerical simulation results show that the process of roof crack evolution after the primary excavation section and the second excavation section can be divided into three stages according to microseismic activities, and the reasonable supporting time can control the propagation of roof microcracks and reduce the development height of macrocracks. The rock bridge existing in the roof rock stratum after the combined support of long and short anchor cables can effectively limit the formation of macrocracks and their interaction; especially the key support in the interface area can reduce the development height of roof cracks in secondary tunneling and weaken the damage degree of roof rock stratum in the LODM. The field test shows that the moved volume of rib-to-rib and roof-to-floor of the LODM is stable at about 350 mm and 550 mm, respectively. The numerical simulation in this paper is helpful to understand the failure mode of roof in LODM with large mining height and provides a method for the design of its control technologies.

Research on the Evolution Characteristics of Floor Stress and Reasonable Layout of Roadways in Deep Coal Mining

The safe and efficient mining of deep coal resources is severely restricted by the dynamic disasters caused by high gas and high ground stress. Taking a deep mine in China as the research background, a mechanical model of the front supporting stress with the working face was constructed through theoretical calculations. Based on the limit equilibrium theory, the stress distribution in the plastic zone and the elastic zone of the lateral working face was derived; based on semi-infinite plane mechanics model, the floor vertical and horizontal stress distribution was deduced. Then, the roadway surrounding rock stress and displacement field distribution evolution characteristics were revealed through numerical simulation. On this basis, the reasonable floor gas drainage roadway (FGDR) layout was determined: internal staggered layout was used with FGDR, the vertical distance to the working face is 20 m, and the horizontal distance to the working face end is 15 m; the open-off cut of FGDR was arranged in an external staggered layout, the vertical distance to the working face is 20 m, and the horizontal distance to the open-off cut of the working face is 15 m. It is an important practical significance for the layout of FGDR, the control of surrounding rocks, and the improvement of gas drainage effects under similar conditions through the research results.

Mechanism of Overlying Crack-Stress Evolution When Mining on the Dual Fault Zone

To study the fissure-stress evolution law of overburden rock in the process of working face advancing in the dual fault area. This paper took the geological occurrence condition and actual mining situation of working face 21,129 of Tucheng mine as the engineering background. The method of similarity simulation combined with field measurement was adopted. The evolution law of the stope fissure field, the stress variation trend of roof fault, and migration characteristics of overlying strata in the process of stope mining through dual faults were studied. The results showed that: Dual faults had a large effective area on the surrounding rock of the stope, the surrounding rock movement in the affected area was intense. When the working face advanced to the fault F2 area, the energy generated during the surrounding rock movement of the fault F2 was transferred to the fault F1, which intensified the activity of the rock in the fault F1 area. The activation of the fault F2 caused the fissures in the surrounding rocks of the fault F1 to expand further. The surrounding rock of the stope changed from a single-fault action mode to a double-fault joint action mode. According to the degree of development of cracks in the roof of the overlying strata, the stope’s different positions were sorted from large to small as follows: fault activated fracture zone > central dual fault zone > open-off cut zone > middle of the non-fault affected zone. The field measured data showed that the area affected by the dual fault was composed of “high-pressure area” and “low-pressure area.” The working resistance value of hydraulic support was higher than that of the non-fault affected area. The law of fracture development and distribution in overlying strata of stope in similarity simulation experiments were consistent with the law of roof pressure measured in the field.