The Application Study Of The Rigid Flexible Piles On The Soft Foundation Test Of The Highway

In recent years, the economic of our country has developed quickly, and ourcountry has payed more and more attention to the construction of infrastructure,especially in the highway construction. Since the western development the western areahighway construction develops rapidly.however, the western area landform restricts itsdevelopment badly, and the treatment of soft foundation in mountain area is a veryimportant reason. Therefore,studying on the characteristics of the soft foundation inmountain area and the processing methods is an important topic of highwaydevelopment in western.The composite foundation has played an important role in the treatment of soft soilfoundation in mountainous areas so far. Rigid flexible pile composite foundation is onetype of composite foundation proposed recent years. The main working mechanism is asfollows: using the properties of rigid pile composite foundation to effectively control thesettlement of composite foundation and improve the bearing capacity of the compositefoundation; making full use of the flexible pile to improve the bearing capacity ofshallow foundation. Domestic and foreign scholars have neither studied it moresystematically and further, nor more perfect design theory and calculation method. So itis necessary to study.This paper mainly relied on science and technology project of GuiZhou provincetraffic hall-GuiZhou highway soft base processing key technology research anddemonstration projects”. Collect,analysis and summary the existing related researchresults;summary the definition of soft foundation, the failure form of soft soilfoundation in GuiZhou area and the treatment method of it; review the bearing capacityof composite foundation calculation and settlement calculation formula,which providesthe basis for the settlement and the calculation of bearing capacity of rigid flexible pile;use the rigid flexible combination of specific engineering design of pile compositefoundation, the bearing capacity and settlement calculation results can meet the designrequirements. Comparing with other methods,we found that the rigid flexible pilescomposite foundation can reduce the cost than other processing methods.In addition, we conduct computer simulation to rigid pile composite with the helpof plaxis;change the factors of the Composite Foundation; study the effects of variousfactors on the settlement, then we reach the following conclusions: ①The thickness of the cushion has a significant impact on Rigid composite pilefoundation settlement, we can find nonlinear relationship between Cushion thicknessand Rigid composite pile foundation settlement;②The length changes of rigid pile greatly affect the settlement of foundation;③The length changes of Flexible pile has little affection on the settlement offoundation;In short: what we studied provide the basis for the use of Composite Foundation, itis helpful to Composite Foundation on soft foundation treatment too,effectively makesure of the safty in Guizhou Province...