The Design Theory And Application About Retaining Wall On Supported Beams Of Micro-Pile Foundation

Micro-pile is a type of small diameter bored pile constructed by strong reinforcement and pressure grouting, of which the diameter is between 100 and 300mm. At first, micro-pile is considered as a whole structure to bear vertical loads. However, in recent twenty years, due to the development of micro-pile technology, the views on bearing capacity of micro-pile have been changed. It is gradually realized that single micro-pile is also able to resist lateral loads. And micro-piles are used in foundation pit supporting, slope controlling and reconstruction projects after earthquake.This dissertation aims at studying the design of a new retaining structure which is micro-pile loading balance weight retaining wall.This dissertation is based on an engineering project-the high way from Ankang to Chongqing. Considering in situation of the slopes and the loads acting on the structure, the author analyzes the current design theory of the structure.The main results and conclusions can be expressed as follows.(1) Collecting data on application and theory calculation of micro-pile and retaining wall on supported beams of pile foundation at home and abroad; studying the design of a new retaining structure which is retaining wall on supported beams of micro-pile foundation.(2) Determining the load types and the distributions on the influences of micro-pile structure loading balance weight retaining wall; discussing the calculating methods of earth pressure and the thrusting force of land slide acting on the structure; introducing the structure distribution of the thrusting force of land slide.(3) Doing theory calculation of this new retaining structure first to calculate the loads which are from the up-structure to pile top,according to the different assuming conditions. Then caculating the deformation and internal force of micro-pile.(4) Analyzing displacement changes and stress distributions by using PLAXIS numerical analysis software to establish model; comparing the theoretical results with the numerical ones to examine the suitability of the modeling.