欠固结地基桩基工程设计优选

Design optimization of pile foundation in under consolidated ground

针对欠固结场地的高层建筑的基础工程进行设计优选。待建场地为表层欠固结素填土,中层粉质粘土到卵石过渡,下层为风化程度不一的岩层,总体评价场地属较硬质地基,但是由于表层欠固结土分布较厚,范围不均,下层岩面起伏较大,考虑采用穿越欠固结土的桩基承载方案。分别对预制桩、冲(钻)孔灌注桩、人工挖孔桩进行设计计算、施工工艺和经济性比选,选择冲(钻)孔桩,作为承载桩。

In this paper,the foundation design of high-rise buildings in under consolidated site is optimized. The site to be built is the surface under consolidated plain fill,the middle silty clay to pebble transition,and the lower layer is the rock stratum with different weathering degree. The overall evaluation site is relatively hard foundation. However,due to the thick distribution and uneven range of the surface under consolidated soil,and the large fluctuation of the lower rock surface,the bearing scheme of pile foundation passing through the under consolidated soil is considered. The design calculation,construction technology and economic comparison of PHC pile,bored pile and manual dug pile are carried out respectively,and the bored pile is selected as the bearing pile.