筒型基础负压沉贯后筒内水膜现象的试验研究

筒型基础负压沉贯过程中将产生土塞现象,松散的土塞回落后会在筒内上部形成一层水膜。在筒型基础的使用阶段,水膜高度将在荷载作用下发生变化,造成筒基竖向位移,严重时将影响上部结构的正常使用。试验通过向沉贯后的筒基内灌入不同配合比的泥浆来解决水膜现象。试验选取了三种典型土体(砂土、粉土和粉质粘土),通过观测和数据分析,砂土情况的灌浆效果最为明显,其次是粉质粘土和粉土。

Model Tests Study on Phenomenon of Water Layer in Bucket Foundation after Penetration by Suction

The phenomenon of soil plug is found in the process of penetration of the bucket foundation by suction. Water layer is formed in the top of bucket when the loose soil plug sinks. In the usage period, the height of water layer varies with the loading action, which causes the displacement in vertical and even may impair the use of upper structure. In order to dissolve or reduce the influence of the water layer a series of model tests is designed, which infuses the mud of different mix proportion into the buckets. Sandy clay, silty sand, and clay which are as typical soil are chose in the tests. By observation of water layer and analysis it is found that the effect of grouting is the best when it's in the sandy clay, secondly is in the clay.