真空-堆载加固胶州湾软基现场试验研究

Field testing on strengthening of soft soil by vacuum-surcharge preloading in jiaozhou bay

结合现场监测数据,对真空-堆载联合预压加固软基过程的地表沉降、孔隙水压力、水平位移和地下水水位随时间的变化规律进行分析。分析表明:真空联合堆载预压能加快地基沉降的速率,缩短施工工期;真空联合堆载预压对浅层土孔压变化影响明显,而对深土层孔压变化较为缓慢;抽真空开始后土体水平位移方向是指向加固区内,而堆载预压阶段是指向加固区外;真空联合堆载预压减少地基的水平变形,提高了地基的稳定性。

The development of vacuum-surcharging preloading method is briefly introduced.Based on the field monitoring data,the change law of surface settlement,pore water pressure,horizontal displacement and water level by vacuum-surcharging preloading method with time are analyzed.The results show that the vacuum-surcharging preloading method can speed up the rate of foundation settlement and shorten the construction period.The change of the pore water pressure in shallow soil is obvious while in deep soil is slow in the process of vacuum-surcharging preloading.The direction of the horizontal displacement in the process of vacuum preloading turns to the inside of the strengthened area,while in the process of surcharge preloading it turns to the outside of the strengthened area,vacuum-surcharging preloading method reduces horizontal displacement and improves the stability of the foundation.