Numerical experimental study on optimum design of anchorage system for Xiashu loess slope

Abstract

In FLAC^3D, cable element or modified pile element can be used to build slope anchoring model. However, the difference between the two structural elements and their influence on the calculation results have not been studied in depth. In order to solve this problem, the Xiashu loess slope anchoring models based on cable element and modified pile element were constructed respectively. A variety of anchoring schemes were designed by orthogonal experiment method, and then they were brought into the model for calculation and the calculation results were analyzed by range analysis and variance analysis. The results show that the modified pile element can bear the bending moment and reflect the strain softening property of the grout. From the perspective of slope safety factor, the anchorage length and anchor bolt spacing are the main factors affecting the stability of the slope, and the anchorage angle is the secondary factor. The grout in cable element is assumed to be an elastic-perfectly plastic material, so the safety factor of the slope can be significantly increased by increasing the length of the anchor bolts. This will bring potential risks to the slope treatment project. Therefore, in the calculation of the slope anchoring model, the modified pile element is more suitable for simulating the anchor bolt.

Keywords

Xiashu loess slope / anchorage system / cable element / modified pile element / orthogonal test

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