软土主、次固结变形机理分析及试验研究

Mechanism Analysis and Test on Primary and Secondary Consolidation Deformation of Soft Soils

软土性质软弱,易产生变形,对其在不同加荷比下的工程特性进行研究很有必要。从地下水动力学理论出发,对主、次固结变形机理进行了分析。对3种软土进行了一维固结试验,试验结果表明:压缩指数与液限和塑限具有良好的线性关系;相较于加荷比等于1的情况,加荷比小于1时,主固结阶段变形明显减小;加荷比小于1时,次固结变形存在由慢到快的变形趋势,但次固结系数较加荷比等于1时减少明显。试验成果对工程实际具有一定的指导作用。

Soft soil is weak in nature and prone to deformation,therefore it is necessary to study its engineering characteristics under different load increment ratios.The mechanics of primary and secondary consolidation was analyzed based on the theory of groundwater dynamics.A series of 1-D consolidation experiments for three types soft soil was carried out.The results of experiments show that：（1）C_chas good linear relation withω_Landω_P;（2）compared with condition ofΔp/p=1,whenΔp/p1,primary consolidation was reduced obviously;（3）whenΔp/p1,secondary consolidation exist the tendency of deformation from slow to fast,but C_αwas obviously less than condition ofΔp/p=1.The mechanism of these experiments were explained.