摘要
离层破碎型顶板的煤巷难以采用常规锚杆支护的原因是易于发生松脱型和挤压型顶板垮冒,并导致锚固区内、外离层两种形式的支护失稳.研究表明巷道帮顶交接的围岩内部有一个相对稳定的区域,利用它作为锚固基点的钢绞线桁架结构可以强化煤巷顶板已有的锚固区,形成可靠的承载结构,向上的扭矩消除了复合顶板锚固层的整体离层破坏.通过分步实施高性能预拉力锚杆、顶板小孔径预拉力锚索和上帮角煤岩体为锚固基点的钢绞线预拉力桁架系统可以实现离层破碎型顶板的安全控制.
Broken roof of roadway is prone to the following two types of caving： caving induced mainly by gravitational force and caving extruded mainly by horizontal force, which will lead to roof separation within and outside of the bolting zone. So the application of common bolting support of roadway is greatly limited in this case. However, studies show that a relatively stable zone exists respectively within the roof-wall adjoining surrounding rocks. The steel strand truss system taking this area as basic anchoring points may strengthen the former bolted zone of the roof, and form a firm bearing structure. Meanwhile the whole discrete rock strata of roof reinforced by multi-compound supporting can be further controlled because of the upward torsion power offered by the truss system. Thus, successful safe control can be realized by the multi-compound supporting system consisting of high performance pretension bolting, cable anchor and truss with the roof-wall surrounding rock zone as basic anchoring points.
出处
《采矿与安全工程学报》
EI
北大核心
2006年第1期34-38,共5页
Journal of Mining & Safety Engineering
关键词
离层
煤巷
垮冒
控制原理
roof separation
roadway
caving of roof
control principle
