Compacted Effect Research Of Jacked Opened-pile In Layered Ground

The pile foundation is one of the basic foundation types mainly used in the conditions that the poor geological and the higher construction requirements.With the improvement of civilized construction,the jacked opened-piles has been widely used as one of the basic forms rely on its advantages which construction of environmental pollution-free,material saving,good seismic performance and higher economic benefit and so on.However,in the process of jacked pile were penetrated into foundation,because of it belongs to the part of the compacted piles,the pile layered ground will be disturbed and have a disadvantage to the construction nearby.At present,the method of compacted effect in opened pile is not perfect,in the process of jacked pile were penetrated into foundation,the displacement of soil around the pile is not clear,and the current study generally confined to uniform foundation,the compaction effect of opened pile in layered foundation research is rarely attention.In this paper,the study of the compacted effect of opened pile is carried out based on experiment.The main contents are as follows:the measurement and analysis of the displacement of soil around the pile when piles jacked into uniform hard foundation,uniform soft foundation and layered foundation which is soft foundation in hard foundation below;design the visual model test;spread layered soil by a definite porosity;through high-definition camera to shoot the process of jacked pile of half mode pile;using image analysis software to realize automatic calculation and high precision measurement;draw the data to figure into analysis and on the basis of model.PFC2 D method is introduced to simulate the process.through the biaxial experiment to the test of soil and the soil of numerical model soil and adjust parameters approximately to the model test conditions.eventually,compared the test results with the results of numerical analysis,come to the conclusion that the regular of the displacement of soil around the pile is different between layered ground which soft foundation in hard foundation below and uniform foundation.Meanwhile,the study proved that by modifying the microscopic parameters of the numerical model can achieve similar with real material constitutive behavior,and revealed that the numerical simulation and model test of compacted effect have a good consistency.