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The distribution range of soil-rock mixtures (S-RM) in fault zones is wide, with significant differences in mechanical properties, making them the main sites for rock instability and support structure failure in mines. This paper takes the Sanshan Island fault zone as the engineering background, and uses a self-designed small-scale test device to conduct triaxial compression tests to study the strength and deformation failure laws of S-RMs with different rock block proportions (20%, 40%, 60%, and 80%). Combined with numerical simulation test results, the spatial transport laws and microscopic deformation failure characteristics of particles with different particle sizes in the S-RM are revealed. The main conclusions drawn are as follows: (1) For S-RMs with rock block proportions (RBP) of 20%, 40%, and 60%, there is a linear positive correlation between confining pressure and peak strength. When the RBP increases to 80%, there is a non-linear positive correlation between the confining pressure and peak strength of the S-RM sample. Under the same increase in confining pressure, the increase in peak strength of the sample decreases. The influence of confining pressure on the strength and deformation characteristics of S-RMs with high RBP is reduced. (2) During the process of increasing the RBP from 20 to 60%, there is a linear positive correlation between the RBP and peak strength of the S-RM sample. When the RBP increases to 80%, the peak strength of the sample experiences a sudden increase, with an increase of nearly 80 kPa in peak strength. When the RBP is high, the S-RM sample exhibits the mechanical properties of block rocks. (3) The cohesion and internal friction angle of the S-RM sample are positively correlated with the RBP. During the process of increasing the RBP from 20 to 80%, the cohesion increases from 83.12 kPa to 119.38 kPa, and the friction angle increases from 6° to 11°. (4) When the RBP is low (20% and 40%), as the experiment progresses, a significant conjugate shear deformation zone will form within the S-RM sample, and block rock particles will migrate towards this area and undergo shear slip failure between particles. When the RBP is high (60% and 80%), splitting failure mainly occurs at the bonding surface between block rock particles and soil particles inside the sample, and the contact force between particles is relatively large. The relevant research results have important social and economic value for revealing the fracture failure laws of rock masses in fault zones and ensuring the safe development of human engineering activities. [ABSTRACT FROM AUTHOR]

By using of theoretical analysis method, the structural mechanical model of roadway driving along next goaf was established, and the width expression of internal stress fields was derived, the rational position of roadway driving along next goaf was determined and the deformation of the surrounding rock was also calculated. Meanwhile, the parameter of roadway was given. At last, the control technology of roadway driving along next goaf in thick seam was put forward, and the first is high strength and pretension bolt supporting to control roof,the second is decreasing bolt interval of roadway gob-side, the last is secondary supporting to the integrated coal side of roadway, based on this, the bolt supporting parameter was determined by system information design method, and it is successfully applied to engineering practile. [ABSTRACT FROM AUTHOR]

According to the situation of gob-side entry retaining with the large and uneven deformation and poor support effects, took gob-side entry retaining in Qinxin colliery as engineering background, dealt with the numerical simulation analysis the relationship between support inside roadway, surrounding rock deformation and stress distribution, and the obtained support mechanism inside roadway of gob-side entry retaining are as follows: with the application of support with high resistance and yielding, increasing carrying capacity and deformation resistance of surrounding rock in roadway, adapting to large deformation and stress adjustment. The developed support technologies inside roadway of in gob-side entry retaining are:(1) basic support: using high-strength bolt and anchor support owning high pre-stress force, increasing carrying capacity of surrounding rock and adapting to large deformation; (2) reinforced support: within a certain range behind working face, in gob-side entry retaining, the hydraulic support with high resistance and yielding is used to strengthen roof and floor support, which means that in the intense stage of roof breakage and stress adjustment of surrounding rock of gob-side entry retaining, the hydraulic support can be used to support the roof and floor effectively and reduce the rotating, sinking of roof and floor heave, maintaining the stability of surrounding rock in gob-side entry retaining; (3) after the surrounding rock deformation stability in gob-side entry retaining, the hydraulic support used as reinforced support can be removed. [ABSTRACT FROM AUTHOR]