浅基础地基承载力与变形特性离心模型试验研究

摘要

采用土工离心模型试验方法 ,对装样、饱和、加载等试验技术进行研究 ,以保证试验重复性与可靠性 ,并分别从承载力与变形两个方面对浅基础地基问题进行试验研究.研究结果表明 :对圆形和方形浅基础而言 ,密砂地基的竖向荷载-位移曲线具有明显的拐点 ,竖向荷载在曲线出现拐点以后的变化不明显 ;分析地基承载力系数时 ,达到地基承载力 qu 时的基础沉降对地基承载力系数 Nq 的影响不明显 ,对 Nr 的影响比较显著 ;基础形状的变化对于 Nq 的影响不明显 ,对 Nr 的影响比较显著.%Based on the principle of geotechnical centrifugal modeling test , the experimental techniques of sample preparation ,sample saturation and loading are studied to ensure the repeatability and reliability of the modeling tests . And then , the modeling studies of shallow foundations are performed in respect of bearing capacity and deformation .It could be seen from the test results that :there is an obvious inflection point at the curves of vertical load-settlement for circular and square foundations on dense sand ,and the variation of the vertical load is not obvious after the appearing of the inflection point .When the bearing capacity factors are analyzed with the experimental results ,the settlement corresponding to the bearing capacity qu imposes little influence on the bearing capacity coefficient Nq ,but it imposes apparent influence on Nr . The variation of foundation shape imposes little influence on Nq ,but it imposes apparent influence on Nr .