Manufacture Of The Inside-opened Umbrella Soil Anchor And Study On Its Anchoring Capability

The soil anchor technology is an important part of geotechnical anchor technology, used in a very wide range of foundation pit support and slope protection works. It makes a good anchoring effect, and has made a great contribution to China's cause of building. At present, most of the anchors in the natural soil are grouting anchors. In the good soil conditions, the effect of its application is very good, but in poor soil conditions, it often leads to inadequate bearing capacity of anchor and too large displacement because of low soil shear strength and high compression, so that it brings certain limitations to the application of the soil anchor. With the development of many new anchor structures, the anchor applications gradually increased in poor conditions soil. Among them, the bit expanded anchor structure is highly respected by people. It changes the providing way of the anchor pullout resistance from the traditional friction resistance to end bearing capacity of the soil, greatly improving the pullout resistance of the soil anchor.The inside-opened umbrella soil anchor, proposed in recent years, has simple structure, easy construction way, high bearing capacity, fast anchoring and other advantages. But the theory of the inside-opened umbrella soil anchor is not perfect, so it is necessary to carry out in-depth study.This paper describes the construction and processing of the inside-opened umbrella soil anchor, analyzes its anchoring mechanism and failure modes, and gives the jacking force estimation formula and the pullout resistance estimation formula which are combined with tests.In addition to theoretical research, this paper takes a numerical analysis with the FLAC3D software and gets some useful conclusions.