拉力集中型与压力分散型预应力锚索锚固机理

Anchoring mechanism of prestressed anchor cables under concentrated tension and dispersive pressure

  • 摘要: 利用有限差分程序FLAC对一种新型预应力锚索——压力分散型锚索的锚固机理进行了数值模拟研究.与拉力集中型预应力锚索相比,压力分散型锚索具有许多优点,尤其适用于对大变形软岩工程的锚固.对比分析结果表明:压力分散型锚索锚固段浆体轴力峰值仅为拉力集中型锚索的1/n(n为承载体的数量),且浆体处于受压状态;锚固段浆体-岩体界面上的剪力峰值也小于拉力集中型锚索,并沿内锚固段轴向均匀分布;在相同条件下,压力分散型锚索比拉力集中型锚索能提供更大的锚固力;适当增加承载体的数量是提高压力分散型锚索锚固力,改善锚固段浆体受力状态的有效途径。

     

    Abstract: The anchoring mechanism of a Pre-stressed Anchor Cable under Dispersive Pressure (PACDP) was studied with FLAC software. Compared with a Pre-stressed Anchor Cable under Concentrated Tension (PACCT), the PACDP has several advantages and is more suitable for supporting soft rock with large deformation. The peak value of axial stress of the PACDP is only 1/n of that of the PACCT, where n is the number of supporters and the grouted part is in compression. The peak value of shear stress between the grouted part and the drilling wall of the PACDP is also smaller than that of PACCT and evenly distributed along the axis of the anchor. The PACDP can provide a larger anchoring force than the PACCT. It is concluded that pre-stressed anchoring under dispersive pressure is an effective way to enhance the anchoring force and improve the mechanical conditions by suitably increasing the number of grouted parts.

     

/

返回文章
返回