Abstract In coal mining roadway support design, the working resistance of rock bolt is key factor affecting its maximum load. Effective improvement great significance to support. Based on bolt’s tensile characteristics and surrounding deformation, a mechanical model for calculating was established solved. Taking 17102 (3) face at Panji No. 3 Coal Mine China as research site, with quadrilateral ...

In order to study the stability control mechanism of deep soft rock roadway and active support technology anchor-grouting flexible bolt, this paper takes west wing transportation Yuandian No. 2 Coal Mine Huaibei Mining Co., Ltd., Huaibei, China as research background. By analyzing occurrence conditions failure characteristics surrounding structural mechanical properties combined with elastic–pl...

To study the evolution law of axial force and shear stress a full-length anchorage bolt in rectangular roadway during driving working face mining, based on analysis bolt, considering elastic parameters geometric size effect bearing plate surrounding rock, cross-section shape, deformation degree, parameters, mechanics mathematical methods were used to establish mechanical model describing intera...

An experimental study is presented on the effects of bolt-hole clearance on the load distribution in multi-bolt composite joints. Single-shear, three-bolt joints were studied. The specimens were manufactured from graphite/epoxy HTA/6376, with quasi-isotropic lay-ups. Protruding head bolts of 8 mm diameter and torqued to finger-tight conditions were used. Different combinations of clearance were...

During the maintenance of workings, effects soil rock heaving, caused by plastic deformation and extrusion into excavation cavity under action pressure, are usually eliminated. The identified patterns change in stress-strain state coal-rock massifs (displacements, stresses, cracking zones), depending on main mining-geological mining-technical factors will allow to establish optimal parameters a...

Abstract Rock bolts are one of the main measures used to reinforce unstable blocks in a rock mass. The embedment length fully grouted stable and competent stratum behind is an important parameter determining overall bolt length. It required that section must be longer than critical ensure will not slip when loaded. Several series pull tests were carried out on rebar evaluate pull-out mechanics ...

Combined with specific engineering examples, the spatial disturbance influence characteristics and laws of surrounding rock stress in staggered roadways are analyzed by numerical simulation. This paper concludes that (1) compared pressure behavior general roadway, stability roadway is relatively poor, showing local serious behavior, such as intensified destruction side, failure fracture penetra...

The control difficulty of whole coal cavern groups is greatly increased due to the characteristics soft rock with low strength, large sections, and mutual influence crossed groups. section gas storage group taken as research background. In this paper, equivalent circle method used solve loose a rectangular roadway, numerical calculation obtain deformation stress distribution laws surrounding un...