| Resin bolt is the main support technology of coal roadway in the world at present.According to the different amount of resin anchorage agent used,it can be divided into three kinds of anchorage methods:end anchorage,full-length anchorage and lengthened anchorage.The working anchorage force of end anchorage is relatively optimal.Full anchorage and lengthened anchorage are paid attention to because of the use of the same size resin cartridge,the changeable lithology of anchoring environment and the pre-tightening force of anchor.In order to break through the theory and technology of bolt support and achieve the full-length stress of bolt body while applying pre-tightening force in the full-length range of bolt support,this paper makes a systematic and in-depth study by combining theoretical research,laboratory experiments and numerical simulation、On-site industrial.To the following main conclusions:（1）The composition of anchoring elements and types of anchoring forces of classical anchorage system are analyzed,the load transfer mechanism of anchorage section is studied,the analytical solution of critical anchorage length of anchor is obtained theoretically,and the implementation method of increasing the load of anchorage section is discussed from the perspective of Engineering implementation.（2）The experimental scheme of end anchorage and lengthening anchorage is designed by using the comprehensive experimental platform of prestressing anchorage effect.The distribution characteristics of prestressing force in the anchorage section are further analyzed and calculated from the experimental point of view.It is verified that the distribution of full-length prestressing force in the anchorage section is objective,and the critical anchorage length of different anchorage modes is obtained.（3）By using Flac3D numerical simulation software,the influencing factors of full-length prestressing high-efficiency anchorage are studied,and the numerical simulation conclusion that different anchorage lengths can achieve high-efficiency anchorage is drawn,and the pre-tightening force of bolt is positively correlated with the strength of surrounding rock of anchorage section and the anchorage efficiency.（4）Combining with the actual engineering geological conditions of the return air channel in 3204 working face of Taitou Coal Coke Mine,Xiangning County,Shanxi Province,relevant research results are applied and tested.The roof and floor of the roadway and the two sides of the roadway move nearer to 41 mm and 91 mm respectively,which achieves the high-efficiency surrounding rock control effect of the full-length prestressing support of the bolt anchorage section,and provides a new breakthrough for the bolt support of coal roadway in China.There are 65 papers,9 tables and 84 references. |
