天水市城区砂砾石地基的变形特征和承载力分析

本文通过对天水市秦州、麦积两区砂砾石地基进行大量颗粒分析、动力触探、灌砂法试验及人工回填打入预制桩、人工挖孔灌注桩静载荷试验,并对其各项试验结果进行统计,系统地总结了天水城区砂砾石的分布特征、颗粒组成、物理力学性质;并通过粒径直方图统计分析阐明了藉河流域颗粒级配明显好于渭河流域,承载力特征值亦高于渭河流域的几个关键问题,并通过对工程实例的试验检测,对涉及的砂砾石地基的承载力特征值及变形模量,桩的极限端阻力标准值、极限侧阻力标准值应用实际问题进行了对比、讨论和分析,因此对工程质量的检测和设计应用有着重要意义,可供类似工程参考.

The behaviores of deformation and bearing capcity for sandy gravel subsoil in Tianshui urban districts

Based on the results of plenty of grain size analysis,dynamic exploration,sand injection tests and loading tests such as driving pile,cast in place pile on sandy gravel soil in Qincheng and Maiji districts of Tianshui,the paper made a systematic summery of distribution features,grain ingredients,physical mechanic features of sandy gravel soil in the urban area of Tianshui.The paper illustrated by means of histogram that the grain graduation of the Xihe Valley much better than that of the Weihe Valley,the bearing capacity value Xihe Valley is also higher than that of the Weihe Valley.The paper,by means of actual engineering examples,discussed and analyzed the characteristic value of subgrade bearing capacity,modulus of deformation,nominal value of ultimate end resistance of pile and nominal value of ultimate skin friction of pile for the subsoil.It is of great value for engineering designning and test of engineering quality,applicable for reference in the similar engineering.