Study on the anchorage length of FRP bars with bond-slip constitutive relationship;

Analysis of the reliability and anchorage length for anchoring of steels;

Research on the steel plate anchorage length of plated R.C beams;

This article analyzes different "anchoring lengths of steel anchor bolts"chosen from "Design Handbook",according to the calculation principles of "The Design Specifications"in effect through engineering example,presents concrete suggestions,and can be used for reference in design.

A corresponding calculating formula on the ultimate anchoring strength of this material and a suggested table in construction of anchoring length are put forward.

Then the design of anchoring length by reliability analysis is proposed.

In terms of point_and_fully_anchoring of bolts, the compression and consolidation effect of anchoring is compared and analyzed by means of Mohr′s circle and shear strengh envelope curve from the shearing parameters of rock mass and the interacting force offered.

Based on bolting and grouting reinforcing test in site,gap between chamber and soft surrounding rock were feedback analyzed according to grouting statistics data,analyses model was set up by FLAC,the effect of relation between chamber and surrounding rock to support internal force and surrounding rock self-bearing capacity were analyzed.