基于动态压缩模量的路基工后沉降计算研究

基于太沙基单向固结理论,结合土体变形计算公式,推求饱和土压缩模量的表达式.研究饱和土体压缩模量随固结度、固结系数和排水路径的变化规律,并分析了压缩模量的时间效应及其在路基工后沉降预估中的应用研究.结论表明：1）固结初期,压缩模量随固结度增加呈缓慢线性增长;固结度U ＞60％时,压缩模量增长速度加快;固结后期,压缩模量增加很少;2）固结时间相同,压缩模量随固结系数增加而增加;固结系数Cv＜5000 cm2/a时,压缩模量几乎不变;3）双面排水时的压缩模量增长速度远大于单面排水;4）压缩模量随时间呈近似线性增长,且存在上限值;利用动态压缩模量可有效预估路基工后沉降.

Research on calculating post-construction settlement of road foudation based on dynamic compressive modulus

Based on the Terzaghi one-dimensional consolidation theory,combined with soil deformation formula,the mathematical expression of compressive modulus of saturated soil is derived.With the variation of consolidation degree,coefficient of consolidation and drainage path,compressive modulus of saturated soil is studied,and its time effect and its application in predicting post-construction settlement of road foudation is analyzed.The results show：1） With consolidation degree increasing,compressive modulus has linear and slow growth in the early stage of consolidation; Its growth rate becomes larger as consolidation degree U ＞ 60％ ; It has no further increase in the later period; 2） With the consolidation coefficient increasing,compressive modulus increases under the same consolidation time;It changes little as the consolidation coefficient Cv ＜ 5000 cm2/a ;3）Under doubled sided drainage,the growth rate of compressive modulus is far greater than under the single-sided drainage ;4） Compressive modulus approximately increases linearly over time,and it has an upper limit;It＇s effective that predicting post-construction settlement through using dynamic compressive modulus.