淤泥质土固结过程孔压及变形规律研究

The Study on the Pore Water Pressure and Deformation Rule in the Procedure of Mucky Soil's Consolidation

对深入了解土在外荷作用下的孔隙水压力与变形变化规律对研究土的排水固结机理具有重要意义。对黄石地区淤泥质土进行分级加荷与一次性加荷的各向等压固结试验及单向固结试验,分析全过程孔压与变形的变化规律,结果表明:两种加荷方式孔压消散的规律并不相同,当孔压降到相应某临界值以下时,固结过程会变得缓慢,即使在较大的外荷载作用下,土中孔压反映也远不如加载初期明显。固结排水过程具有阶段性,这主要是自由水与孔隙水排水速度变化所引起的。黄石淤泥质土的主固结时间总体在5～100min范围内,当固结压力接近先期固结压力时固结系数最小,而次固结系数约为最大值。

In-depth comprehending of the pore water pressure and the deformation in the procedure of mucky soil＇s consolidation has a significant meaning to study the theory of soil＇s drainage and consolidation. Though the text of the mucky soil in Huangshi Area , by using the graded loading and once loading into same directional stress consolidation and unidirectional consolidation, to analysis the pore water pressure and the transformative rule during the whole process. The result indicates that two loading methods bring to different rules. Meanwhile the consolidation process will slow gradually when the pressure is lower to the threshold. The pressure will not as distinctive as the initial stage, even when the load is great. The mucky soil＇s consolidation in drainage has phases, it is caused by the change of the drainage speed about the free water and the leaked water. The main consolidation speed of the mucky soil is around 5minutes to 100minutes. If the consolidation pressure is close to the initial pressure, the consolidation coefficient is at the min. but the secondary consolidation coefficient is the max.