吹填软土地基改性真空预压法现场试验研究

温州沿海地区通过吹填航道淤泥进行大面积围海造陆,吹填好的大面积淤泥场地通过真空预压进行浅层处理。处理后的吹填场地急需进行工程建设,但其承载力不能满足建设要求。为研究进一步提高吹填软基承载力的方法,划分了5个试验区,采用取消了砂垫层的改性真空预压技术进行不同方案的现场试验研究。对现场监测和地基检测结果分析表明:改性真空预压法在吹填软基的加固处理中可以取得较好的加固效果;加密了水平排水管道和在波纹滤管中套入PVC圆管支撑可以更好地传递真空并提高加固效果;采用改性真空预压联合覆水预压可以保护真空膜、提高膜下真空度,在一定程度上加快软基的固结速度和提高固结效果。

Field test of modified vacuum preloading on dredged fill soft ground

Reclamation is carried out in the coastal area of Wenzhou through dredging sludge from the bottom of waterway in the sea,and large-area sludge ground is formed and then consolidated by vacuum preloading.The dredge fill ground which has been treated is urgent to be used for engineering construction.But its bearing capacity can’t meet the requirement of construction.In order to study the way of improving the bearing capacity,five test areas are designed for field tests.Modified vacuum preloading method without sand cushion is studied in different programs.According to the tests results,modified vacuum preloading method can achieve good results in the reinforcement of dredged fill soft ground.Consolidation effect can be better improved in the condition that horizontal drain pipes are encrypted or braced by PVC pipes inside.Modified vacuum preloading combined with surcharge preloading can protect the vacuum membrane and speed up the consolidation of the soft ground to an extent.