Theory Analysis And Test Study On The Soil Between Lime-soil Compaction Piles

Lime-soil compaction piles of pile sinking compact the soil between them by lateral expanding when making holes. Lime-soil compaction pile foundation belongs to composite one and can obtain obvious technology and economic benefits when it is used to collapsible loess or filled soil, when is widely used in the north-west and north China.Lime-soil compaction pile is one of the most normal and effective soil improvement methods in loess area, especially in collapsible loess ones. There is few analysis and study about the compaction characteristic of soil between piles when making holes. The evaluation methods about the compacted effect between piles are different in the various standards on soil improvement. That is to say, there are differences in selecting the points which represent the average compactive effect of soil between piles. Based on cavity expansion method, the stress change of soil between piles when sinking pile is studied with elasto-plasticity theory. The triaxial compression tests of undisturbed samples are carried our in laboratory. According to the test results, Duncan-Chang model is employed. The evaluation methods about the compacted effect between piles are different in the various standards on soil improvement. In the theoretical analysis of soil compaction characteristic. In order to certificate the results of theoretical analysis, a lot of insitu tests were made.