真空-堆载联合预压试验的沉降规律研究

Ground Settlement Regularities under Combined Vacuum-Surcharge Preloading

真空-堆载联合预压法在软土地区的地基处理工程中已得到较为广泛的应用。通过舟山某工程地基处理过程中的沉降监测,对实际所得数据进行分析,得出影响各监测点土体沉降产生差异的因素有时间和监测点所处的水平面位置。随着抽真空和堆载步骤的实施,土体各层的沉降量在抽真空和堆载初期显著增大而在一段时间后趋于稳定;同时呈现越靠近处理边界的土层沉降量越小,而越靠近处理区域中心的土层沉降越大的现象,沉降沿水平面呈现锅底形。因此,建议今后类似工程中,要达到沉降均匀的目的,减少锅底效应时,应该增加处理区域边界附近的加载量。研究得出的沉降规律,可为今后类似的工程提供较高参考价值。

In foundation treatment engineering,combined vacuum-surcharge preloading has been widely used in soft soil area. By the settlement monitoring in the construction process of a project in Zhoushan,and data analysis,it can be inferred that time and the monitoring point's horizontal position that affecting ground settlement. With the implementation of the vacuuming and stacking steps,the sedimentation of each layer of the soil is significantly increased in the initial stage of vacuuming and stacking and tends to be stable after a period of time. The settlement of the soil layer close to the treatment boundary is small,and the settlement is large close to the center of the treatment area,and the settlement presents a pot bottom shape along the horizontal plane. Therefore,it is recommended that the loading near the boundary of the treatment area should be increased to achieve the purpose of uniform settlement and reduce the effect of the bottom of the pot in the future. This study is of great importance in the improvement of combined vacuum-surcharge preloading and its application in practical projects.