基于强夯实测夯沉量的地基变形模量反演分析

BACK CALCULATION METHODS FOR DEFORMATION MODULUS BASED ON SETTLEMENTS IN DYNAMIC COMPACTION

在运动方程法和能量法等强夯理论基础上,采用位移反分析方法建立二者反演格式,利用易于测量的夯沉量等数据反算地层变形模量,结合北京园博园强夯实验数据,计算并分析了变形模量随夯击次数的变化情况.研究表明,地基变形模量随夯击次数逐渐增大,增幅逐渐减小,变形模量最终趋于稳定：反演得出该实验地基的初始变形模量在5~8MPa之间,夯击7次后在18~22MPa之间,提高幅度约为3~4倍;能量法反演过程相对简便,可在类似工程中推荐采用.

Based on two kinds of consolidating theories, the motion equation method （MEM） and the energy method （EM）, the back-calculation equations are established separately so that the foundation＇s deformation modulus could be calculated using the settlement data of hammer pit, which can easily be obtained in monitoring. According to the dynamic compaction experiment of Beijing Garden EXPO Park, the deformation modulus varies with different compacting times. It is shown that the deformation modulus gradually increases with the number of tamping but the growth diminishes at the same time, and the deformation appears to be stable in the end. The initial deformation modulus is 5-8 MPa and it rises to 18-22 MPa which is 3-4 times of the initial value after the 7th tamping. Besides, the EM method involves a relatively simple calculating process and can be recommended in similar projects.