淮河干流香浮段疏浚泥固结度室内试验研究

针对淮河干流香庙—浮山段高含水率疏浚泥进行了能够测试底部孔压的一维固结试验，研究了土样变形和底部孔压随固结时间的变化规律，探讨了基于太沙基固结理论建立的变形时间曲线法（Casagrande法）和超静孔压消散法得到的两种固结度的差异性状。结果表明：Casagrande法判断主固结完成时，超静孔压消散没有完成，残余超静孔压约为荷载增量的10%~20%；随着竖向荷载的增加，利用两种方法确定的主固结沉降的差异程度随外加荷载呈半对数线性变化；以真空排水工法为例，分析了基于Casagrande法和超静孔压消散法得到的主固结沉降差异程度。

Lab experimentions on consolidation degrees of clays dredged from Xiangmiao-Fushan Section of Huaihe River

A series of one-dimensional consolidation tests were performed on two types of clays dredged from Xiangmiao-Fushan section of Huaihe River with measured pore pressure at specimen base. Based on the experimental data, the difference between the degree of consolidation determined by settlement-time curve fitting method (the Casagrande method) and excess pore pressure dissipation method is investigated. The results show that excess pore pressure is not completely dissipated when the degree of consolidation determined by the Casagrande method reaches 100% and the remaining undissipated is about 10%~20% of the staged loading. Besides, the difference in settlement determined by the two different methods has a semi-logarithmic relationship with the vertical effective stress. In the end, the vacuum drainage preloading is taken as example to investigate the differential magnitude in settlement determined by the two different methods.