对沉降计算中变形参数的几点思考

Some considerations about parameters of deformation of settlement prediction

地基在加载过程中,高应力区的土体单元因为损伤导致非线性变形的产生,地基刚度随应力水平的增加而减小。探讨了切线压缩模量、切线模量、修正切线模量、变形模量及修正变形模量的各自适用条件,指出压缩模量仅适用于完全侧限条件下地基的固结沉降分析,反映的是地基刚度随应力水平增加而增加的情况;修正切线模量由于考虑了对附加应力的修正,比切线模量更加可靠;对于工作荷载不大的线弹性地基,采用修正变形模量计算沉降比采用变形模量更加可靠。

In high stress zone of subsoil,nonlinear deformation is caused by structural damage during loading,and the increase in stress level leads to the reduction of soil rigidity. The applicable conditions of compression modulus,tangent modulus,correctional tangent modulus,deformation modulus and correctional deformation modulus are discussed in this paper,namely compression module is only suitable for the unidimensional consolidation settlement analysis of foundation in which subsoil rigidity increases while stress level increases,and the correctional tangent module is more reliable than tangent module for the consideration of correction has been given to the additional stress. In the same way,the correctional modulus of deformation is more reliable than modulus of deformation for settlement prediction of the linear elastic foundation bearing permissible load.