Analysis Of The H-type Double Pile-anchor Structure

With the rapid development of urban construction in China. Hence utilizingunderground space represents a general trend. It is inevitable to face a morecomplicated surrounding environment when carrying out construction in the centralarea of the city, so the deep excavation supporting technology is indicating itsincreasing importance under these circumstances. This thesis is based on theincorporation engineering of business center of river-west region and Civil DefenseProjects of Xiangtan city, in which an h-type double pile-anchor structure integratedthe double-row piles and the pre-stressed anchorage, and it gives full play to thesuperiority of these two techniques: namely, it can control the deformation ofsupporting structure; meanwhile, it can also protect the peripheral environment aswell as facilities of the foundation pit, providing convenience for construction andmonitoring. Based on previous research and combined with engineering example, thispaper studies the working mechanism, working properties, design and calculationmethod of the composite supporting structure. The main research content of this paperis as follows:(1)This thesis outlines the research status of double-row piles structure andpile-anchor structure, summarizes the calculation model and calculation method of thetwo supporting structure, their respective advantages and disadvantages, as well as thescope of application.(2)Through the analysis and research of computation theory, two kinds ofcalculation models and calculation methods concerning the applied h-type doublepile-anchor structure are introduced, and the comparison of which show that elasticmethod is more applicable than limit equilibrium method in engineering practices.(3)A conclusion was drawn that the h-type double pile-anchor structure, derivedfrom the calculation of the commonly used single pile-anchor structure and thetraditional form of double pile-anchor structure in two other actual foundationexcavation project, by using elastic method, possesses the properties of deformationcontrol, construction and monitoring convenience, and engineering cost reduction.(4)Using the case-based elastic calculation model, the discussion focuses on theinfluential rule that main effecting factors such as passive zone stiffness, the stiffnessof the piles, the distance between two rows and etc. operates on the performance ofthe h-type double pile-anchor structure, provides methods and measures for the control of inner force and deformation of supporting structure, and make appropriatesuggestions on the design of such supporting structure.