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

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.