Stability control technology for deep soft and broken composite roof in coal roadway

In terms of the roof fall,large deformation and difficult support of deep soft broken composite roof in rectan- gular section coal roadway,based on the support theory of bolting and rope,this study put forward the beam-arch bear- ing structure which had the feature of composite beams and composite arch. The geometrical charac-teristics of the an- chorage of beam-arch structure was analyzed,it revealed the formation process and evolution law of the beam-arch an- chorage structure with different anchorage parameters and reflected the anchorage structure effects for different support- ing programs. Four kinds of supporting technology solutions were studied by FLAC3D to simulate the surrounding rock displacement of deep soft broken composite roof and the damage extension evolution of plastic zone. It reveals the con- trol effect of different supporting technology solutions in rectangular cross section coal roadway. The rationality of sup- porting technology scheme based on beam-arch structure in deep soft broken composite roof was validated,and the un- derground industrial test was carried out. Monitoring results show that the supporting technology of beam-arch structure effectively controls the deep soft broken composite roof abscission layer and large deformation. It can maintain the deep soft broken compound roof coal roadway surrounding rock and supporting structure stability and safety.