Regular Sand Foundation Under The Impact Of The Role Of Ground Deformation Model Pilot Study

Dynamic compaction has been rapidly extended to all over the world and successfully used to treat soft ground since 1969 L.Menard applied in treating abandoned stone ground for the first time.Although the theory of dynamic compaction and experimental researches have been gradually developed,and have also made a lot of achievements,but the theory of dynamic compaction and design calculation method is not mature.Because the complexity of ground soil,lacking of system field tests of dynamic compaction and the necessary indoor accurate tests.So far, for dynamic compaction effect,only a rough relationship between the depth of improvmentand the impact energy per drop is used in practical design for the estimation of the depth of treatment,and left to be determined by way of tesing after construction,thus,the design of dynamic compaction is highly empirical and qualitative. Further researches aimed to the rule of the ground distortion are essential and especially desired to consummate the design theories and promote the level of application.This article is a part of research achievement supported by the national natural science foundation of china (NO 50869002) named "The reseach of definition assessment on the effect of dynamic compaction based on the ground deformation ".The model test is established in this dissertation on basis of similar theories.Including the whole model test of outdoor pit and the half model test of indoor glass box.Respectively impose the impact load of different impact energy to sand ground and research the rule of the ground distortion.It is imposed the impact load of six kinds of different impact energy to sand ground in the whole model test, establishing relevant dimensionless equation among the crater depth and soil conditions parameter and construction process parameter,and fitting it use the method of multivariate linear fitting, the equations are verified by project examples.The results show that:the equations can be used to effective evaluate the effect of ground treatment and control the selection of construction technology parameter.Using the indoor dynamic compaction half model test of self-designed,through imposing the impact load of different impact energy to different dry density sand, analyzing sand characteristic of the ground distortion under the dynamic compaction.Using the transparency of model box can read measurement the deformation of the pre-buried coloursand under impact load, and observe the the effect of treatment depth and the influencing depth of the sand particles during impacting,and establishing relevant dimensionless equation among the effect of treatment depth and soil conditions parameter and construction process parameter,which provide a potential approach for the effect analyses and construction control.