To find out the support failure mechanism of high stress soft rock roadway，Zhaolou coal mine is took as engineering background，and based on the detecting，monitoring and analysis of deformation and support failure law，the numerical experimental is carried out. By amending of BEAM element in FLAC3D，the arch support is simulated effectively. The influence of the support strength，stress grade and surrounding rock strength grade to roadway stability(deformation，plastic zone，stress state of support elements) is discussed. The failure mechanism of bearing structure of soft rock roadway at great depth is analyzed in terms of the limitation of anchor net spray support and the necessity of high rigidity and high strength support. Surrounding rock bearing structure is hard to form or is easy to failure while the radial supporting strength is not enough；arch center with certain rigidity and strength is very useful and necessary. Field test is carried out with square confined concrete arch support scheme，this new high strength support system has great effect on surrounding rock stability control.

为研究厚表土层对大采高工作面矿压规律的影响,以亭南煤矿二盘区205大采高工作面为工程背景,采用理论分析、现场实测的方法进行了研究.分析得出:厚表土层对大采高工作面矿压影响具有一定的滞后性.表土层中含有黏土层易“成拱自稳”而在一定距离内对工作面围岩控制影响不大,随着工作面的推进,C19主关键层将弯曲下沉,表土层结构的稳定性受到破坏,主关键层断裂后表土层载荷通过其下伏岩层传递至工作面;工作面推进至198.5m以后来压期间矿压显现明显,主要表现为支架支护阻力及动载系数增大、来压步距减小、来压强度周期性增大;非周期来压期间工作面支架平均工作阻力在后一阶段大于前一阶段,支架工作阻力沿工作面倾向分布呈“中间大、两头小”的形态,机尾一侧阻力较大.

In this work the uniaxial compression mechanical property of rock mass with intersecting multi-flaws are studied with rock-like material specimens. There are two kinds of intersecting multi-flaws taken into consideration--one comprises the main flaw and the secondary flaws，the other one is composed of multi-flaws with the same length of main flaw. The specimens are tested under the uniaxial compression situation. The test results show that：(1) When there are 2 intersecting flaws，the strength of specimen with intersecting multi-flaws is higher than that of specimen with a single flaw. When there are more than 2 intersecting flaws，the strength values of specimen with intersecting multi-flaws composed of a main flaw and secondary flaws are almost same with that of specimen with a single flaw. When there are more than 2 intersecting flaws and the flaws have the same length with the main flaw，the strength and the work to make the specimen failure are less than those of specimen with a single flaw. (2) The increasing number of secondary flaws has little influence on the strength of specimen with intersecting multi-flaws composed of a main flaw and secondary flaws，the increasing number of flaws have great influence on the strength of specimen with intersecting multi-flaws composed of flaws with the same length to main flaw. (3) Most of the strain values correspondent to the strength peak of specimens with intersecting multi-flaws are lower than that of specimen with a single flaw. (4) The fracture initial stress values of specimen with intersecting multi-flaws composed of a main flaw and secondary flaws are higher than that of specimen with a single flaw. Most of the fracture initial stress values of specimens with intersecting multi-flaws composed of flaws with the same length of main flaw are lower than that of specimen with a single flaw. (5) The failure surface of specimen with a single flaw is shear crack，and most of failure surfaces of specimens with intersecting multi-flaws are tense cracks.

Determination of the reasonable width of pillars between roadways is the key for ensuring safety production of large mining height face with double roadways layout. Taking the double tunneling pillar between haulage gate and gas drainage roadway of 204 large mining height face in the second panel of Tingnan Coal Mine as the engineering background，firstly，the failure regularity of pillar between roadways under the effect of double tunneling and two times mining was systematically studied by using the method of field stress monitoring. A 3 m wide of fractured zone near the gob was found，and a 18 m wide low stress zone was realized. The distribution curve of stress in pillar between roadways after the first mining was asymmetric. After the second mining，distribution curve of stress in pillar between roadways was like a asymmetric “saddle”and the cumulative broken at the edge of pillar was more than 9 m. at the same time，the division of pillar between roadways was given after the two times mining，and the reasonable width of pillar between roadways was determined preliminarily to be 5.2—13.0 m. Secondly，the stress evolution law，the elastic-plastic region variation，and the roadways deformation law of 5 different coal pillar that width of 4 m，6 m，8 m，10 m and 12 m were studied by numerical simulation. Various elements such as safety production and resources recovery were considered comprehensively. The reasonable width of double tunneling pillar between roadways in large mining height face was 10m. Finally，the reasonableness of the pillar width was verified by engineering practice. The results can provide a reference for the setting of pillar between roadways with similar mining conditions.

Determination of reasonable coal pillar width is key for ensuring stability of surrounding rock of fully mechanized caving roadway driving along next goaf. Taking track roadway of 11302 workface in Zhaolou colliery as the engineering background，a new side abutment pressure monitoring method was proposed；and the reasonable coal pillar width was determined by using the method of field stress monitoring and numerical simulation. Field stress monitoring and numerical analysis results show that the influence scope of workface side abutment pressure is 50–56 m，and low stress zone width is 12–15 m，considering pillar stress environment，pillar width should not be larger than 7–10 m. Meanwhile，considering being propitious to bolt anchoring，width of coal pillar should not be less than 4 m. Various elements such as coal pillar stability，secondary disaster control and resources recovery were considered comprehensively. Finally，the reasonable width of segment pillar is determined as 5 m. Reasonable pillar width is verified by using large-scale geomechanical model test and field test. Monitoring results show that variation of surrounding deformation along the empty wall is largest，followed by roof and entity wall，floor is least. After roadway driving along next goaf stability，roof to floor convergence is 271 mm；two walls convergence is 359 mm；the effect of roadway surrounding rock is well. Bolts and anchors forces are in their yield range；and set aside a sufficient margin for the recovery period. The results can provide a reference for segment pillar setting in other mines with similar mining conditions.