为使软硬互层岩体中的压力分散型锚索各承载单元能协调工作,充分发挥各自的作用,建立成层岩体和压力分散型锚索的三维数值模型。通过调整锚索各承载单元上的钢绞线数量,得出各种梯级结构布置的压力分散型锚索,进行优化计算分析。通过对比多组方案下的砂浆体与岩体的应力、变形和锚固单元荷载位移曲线,判别出能够适应岩性不均,发挥出最大锚固效应的方案,进而获得优化的压力分散型锚索结构布置方案。分析结果表明,普通的压力均分型布置可能使软岩中的锚固单元首先进入破坏状态,而优化方案下的软岩和硬岩均能协调一致,发挥出极限承载能力。最后,在岩体加固时,为适应岩层不均的状况,归纳总结出可供参考的压力分散型锚索梯级结构布置优化思路。
Three-dimensional numerical models which contain soft-hard interbed and pressure-dispersive anchors are built to study configuration optimization of anchors. The pressure-dispersive anchors with rundle configuration are obtained by changing the quantity of steel strand on each unit anchor;then the numerical analysis of optimization is carried out. Comparing the stress distribution along fixed anchor length and the loading-displacement curves of different unit anchors,the best optimization scheme is selected. The results show that the rundle optimization scheme with nonuniform unit anchors can coordinate every unit anchors in soft and hard rock to reach the ultimate bearing capacity at the same time. In addition,the traditional pressure-dispersive anchors with uniform unit anchors have a disadvantage that the unit anchor in the soft rock will fail at first. Finally,a suggestion of the optimization scheme of pressure-dispersive anchor adopted in soft-hard interbed is summarized.