沿海吹填土地基真空预压加固效果现场监测分析

Field Monitoring and Analysison the Effect of Vacuum Preloading in Coastal Dredger Fill Foundation

温州瓯江口某吹填区道路工程采用真空预压法加固处理,利用十字板剪切试验与静力触探等原位测试方法评估其抗剪强度增长情况,结果表明土体浅部加固效果明显,但其抗剪强度增幅随深度逐步下降。对地表沉降、分层沉降以及孔隙水压力监测分析表明,真空预压在埋深10 m范围内,负压损失较小且加固效果良好;其有效影响深度在10 m以下也是存在的,但随着深度增加而逐渐减弱,在排水板底部5 m范围内的深层土体加固效果不明显。

Dredger fill foundation of a Wenzhou improvement effect was evaluated by the vane shear Oujiang road was improved by vacuum preloading. The teats and static penetration tests. The in-situ test results indicated that the shear strength value of shallow soil was obviously promoted after vacuum preloading, and the increase of shear strength was reducing with depth. According to the analysis of ground settlement, layered settlement and pore water pressure, the following conclusions can be drawn. The negative pressure loss was small and the reinforcement effect was good within the depth of 10m. The reinforcement effect also existed below the 10m depth, but gradually weakened as the depth increased. The reinforcement effect of deep soil within 5m of the bottom ofthe prefabricated vertical drain was not obvious.