Research On The Effect Of Dynamic Consolidation Of Soil Under Different Water Content

Dynamic compaction which is a kind of foundation treatment method has been widely used in various kinds of foundation treatment because of its wide application scope,simple construction machinery,obvious reinforcement effect and low cost.At present,the study on the effect of dynamic consolidation and strengthening mechanism of dynamic compaction has been carried out under different soil,and a lot of practical experience has been accumulated by combining with construction,which has achieved remarkable results.However,for the same kind of soil,the effect of dynamic compaction under different water content is less.Based on this,this paper carried through the 1:8 indoor model test.Five different water content of soil was made for studing the reinforcement effect under the same level of different hammer weight-drop.At the same time,indoor compaction test was compared.Finally,the following conclusions were obtained:1.The optimal water content is found in the dynamic compaction method and compaction test,and the optimal moisture content of the dynamic compaction method is slightly less than the compaction test.2.No matter what the water content of soil is,the cumulative settlement under light hammer with large height of drop is less than that under heavy hammer with small height of drop and light hammer with large height of drop is more sensitive than heavy hammer with small height of drop.Therefore,the reinforcement effect under the construction technology of heavy hammer with small height of drop is better and more uniform when the soil moisture is different.3.When the water content of soil is low,the dynamic consolidation is mainly concentrated on the surface of the soil.When the water content of soil is close to the optimal water content of the dynamic compaction,the relative density decreases with the depth.Whenthe soil water content is high,there is a significant phenomenon of non-uniform compression in the shallow layer of soil.4.The relationship between effective reinforcement depth and water content of soil in the model test can be expressed as: =Y(36.14-20.3+0.91-ɑ)2?? where α is the influence coefficient of combination.5.Based on the analysis of the curve of energy rebound ratio of tamping hammer,it is found that the dynamic compaction efficiency of hammer gradually converges with the number of tamping,which can be used as a new reference standard for dynamic compaction.