| At present, the pile - anchor support system,for its safety, reliability and economical advantages, has been widely used in the process of engineering construction,such as the high and steep slope, deep excavation works and so on. And it makes a large development in the field of geotechnical engineering. Pressure-type anchorage system, as a new anchor, because of its excellent performance in practical application, reflects the higher value. But now the pressure-type anchorage system is far lagging behind the theory of engineering applications. The paper originated from the scientific and technological project of Chongqing technological committee"Anchorage System in the Geological Disaster Control Research"(Grant No. CSTC2008AC0077) and National Science and Technology Support Program project on " Study on Underground excavation Geotechnical reinforcement of key technologies " Sub-topics"Study on Excavation Optimization Method"(Grant No. 2008BAJ06B04-2). In summing up the results of previous studies and field research, analyzed the mechanism of pressure-type anchorage system stress on the basis of theoretical and experimental aspects. Meanwhile, through filed tests, this thesis has analized the application of pressure to anchor (cable) pile - anchor supporting system's anchor cable pull, pile, soil pressure plate and the shaft Moment and pile anchor coordination. On the basis of theoretical and experimental research, the pressure-type anchor (cable) pile system engineering applications are discussed. Some detailed work has been done as follows:①Studies were made on the fore mechanism of pressure-type anchor according to the theoretical analysis and field test. For one hand, the stress of the pressure-type anchorage segments, which were calculated based on the test of the strain of anchorage segments in a small volume of test components– strain brick, was compared with the elasticity solution of it. For another, study on the mechanism and the force bearing capacity comparative of traditional tension-type cable and pressure-type cable, to obtain the bearing of pressure-type cable is better than tension-type anchor conclusions.②The paper chose commonly used pile - anchor support system to do the filed test, and make an engineering application study on pile - anchor support system which used pressure-type anchor. The environmental retaining wall ABCDE segment of the Agriculture and Life Sciences college building has been designed with prestressed piles - plate retaining wall, in order to back up the support system. The test measured the stress of the support system's piles, the soil pressure of the plate, the cabal and the steel in the piles with force senser. And through tension test to get the P~s curves of pre-stress anchor cables used in the pile - anchor support system. Through the contrast and analysis of the P~s curves from tension-type anchor and pressure-type anchor, we can get their different deformation behaviors.③The pit excavation , tension of the prestressed anchor cable, and the process of plain fill and the work condition of the completion support system are monitored during the entire process, so that we can attain a great deal of on-site tests data. Through comprehensive on-site monitoring work and analysis on the prestress value and loss of anchorage cable, the soil pressure of the pile and plate, we can get representative moment graphs of the pile.Then the author compared with theoretical values, analysis coordination and anchor pile anchor performance situation of pressure-type cable support system in the application .Finally, on the basis of theory and analysis of field tests, the pressure-type anchor (cable) and the interaction of piles supporting system design method and pressure-type anchorage system practical application issues are discussed, and some references for the pressure-type anchor Rod's applications will be provided by this paper.
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