构造板独立基础地基反力的数值模拟

Numerical simulation on ground back pressure of spread foundation with concrete slab

为了研究构造板独立基础与地基土共同作用问题,通过建立上部框架结构,下部构造板独立基础和地基土的整体模型,分析了构造板独立基础的受力变形特点,给出了基础薄弱点的位置及地基反力的分布规律,并进一步研究了各种因素对地基反力分配比的影响。结果表明:构造板的受力类似四角支承的双向板,构造板与独立基础的交界处是受力薄弱部位;基底反力分布呈波浪形,独立基础下反力最大,构造板跨中反力最小;构造板能分担一部分上部结构载荷,底板越厚,刚度越大,分担的载荷相应增加;地基刚度越大,底板分担的载荷越少。该结果对此类型的结构设计问题具有一定的参考价值和指导意义。

In order to study the interaction on spread foundation with concrete slab and foundation soil,a comprehensive model composed of top frame structure,spread foundation with concrete slab and foundation soil was built.Based on the model,the stress and deformation characteristics of its foundation was analyzed,the weak region on the slab and the distribution of the ground back pressure were obtained,also the influences of various factors on the proportion of ground back pressure were investigated.The results show that the stress characteristics of the slab and the four-corner-supported two-way slab are similar,and the interface between slab and independent foundation is a weak load-bearing area.The foundation reaction presents a wave distribution,which has a maximum value under the independent foundation,and a minimum value under the mid-span of the slab.The slab can share part of the upper structure loads.The thicker the soleplate,the larger its stiffness,and correspondingly,the shared load will increase.The lager the foundation＇s stiffness,the less the soleplate＇s share load.The results provide a good reference for solving this type structure design problems.