The FEM Analysis Of The Long-short-pile Composite Foundation Character And Engineering Application

With the rapid development of society and economy, there are many material varieties with the related conception of the foundation design, many new conception have been proposed in the field of the foundation design, many new types of the foundation have been put into construction. The long-short-pile composite foundation is one of them.Firstly, the research production of foundation-settlement calculation and basic theory are summarized,and the research production in long-short-pile composite foundation is specially introduced.Secondly, the distribution pattern of axial stress of long pile and short pile and additional stress of whole-long-pole composite foundation, whole-short-pile composite foundation, the long-short-pile composite foundation, without cushion composite foundation and natural foundation are obtained by using 3D FEM. The influence of cap and the stress adjustment by the modulus and thickness of the cushion on the settlement is discussed.Finally, an engineering case in Changsha city is analysised ,the theoretical calculation results are compared with the monitor in site, the close results are showed to testify the applicability of the long-short-pile composite foundation, and have important engineering value in further analysis and application to the long-short-pile composite foundation.