水泥搅拌桩有效桩长的相关探讨

Discussion About Effective Length of Cement Mixing Pile

分析了水泥搅拌桩单桩静载试验成果,发现有效桩长是真实存在的,在有效桩长外加大桩长并不能提高搅拌桩的承载能力。提出了以桩侧摩阻力作为控制条件确定有效桩长的方法,同时分析了桩顶荷载、桩体刚度、桩身强度等因素的影响,发现桩顶荷载越大、桩体刚度越大,荷载越容易传递到桩身下部,因而有效桩长越长;当桩身强度合格时,分析得出的有效桩长是真实的,而当水泥土搅拌不均、桩身不连续、强度过低,则显示出较小的、虚假的有效桩长。

On the basis of the results of single pile capacity form static load test of cement mixing pile,it is found that effective pile length is real existing, and bearing capacity of mixing piles can＇t be improved with additional increase of pile length. A method for determining effective pile length is approached, mainly according to lateral friction resistance of pile, by the meantime, the effects of loading on pile top, pile stiffness and pile strength are considered. It＇s showed that the greater the loading on pile top and the pile strength, the more easily the load can be transmitted to the bottom of pile, so the longer the effective length. When the pile strength is qualified, the analyzed effective length is true. However, when non-uniform mixing of soil-cement, discontinuous of pile and too low strength of pile are existing, a smaller and fictitious effective length is presented.