Study On The Test Of Inflatable Anchor

Inflatable anchor is one which was applied in the latest. It was aimed to solve the retaining project of civil engineering in soft soil area. Inflatable anchor is that steel pipe was setted by rough rubber mold with steel rings fixed. The segment of steel pipe with rubber mold was drilled proper small holes with it inflate gas. By the way of inflating air with the steel pipe, rubber film in the end of the steel pipe expanded to squeeze the surrounding soil. Anti-pull force was provided by friction between rubber film and soil and the resistance of enlarge head. Inflatable anchor was constructed simple, quick and easy to operate; Timber is simple and can be recycled; Once the anchor was constructed, it can provide the all anchor force which saved the construction period; The anchor was constructed with no waste liquid and gas,no noise which could protect environment; Inflatable anchor could be constructed under the water to provide the anchor resistance for ocean and port engineering which the grouting anchor could not complete.At present the studies about inflatable anchor is still in the initial stage abroad and there is a little report about the field in domestic. This article mainly analyzes ultimate pullout force and deformation of the inflatable anchor in detail based on all kinds of basic experimental, it also gives an exploratory analysis of the anchoring mechanism and bearing capacity formula.The main research works and conclusions are as follows:(1) The structure of inflatable anchor was analyzed and thorough research was carried out on choice of materials which obtained the best material. According to the performance requirements based on the uplift test, the inflatable anchor was designed for laboratory test and field experiment.(2) The device for laboratory test and field experiment was designed. The influence factors of anchor limit resistance was analyzed based on the lots of valuable test data which was concluded by a lot of tensile test.(3) A set of device was designed which was used to control the swelling volume of inflatable anchor. Mass data about the relation between the inflation pressure and the swelling volume of inflatable anchor was obtained by the test of the deformation of inflatable anchor in sand and soft-soil.(4) The inflation body of inflatable anchor was taken as cylinder, the deformation condition of the soil was analyzed with cavity expansion theory and the anchor mechanism was analyzed, which the empirical formula of anti-pull force of inflatable anchor was concluded.