Calculation And Experimental Study Of The Settlement Of Pile Foundation In Zhanjiang Group Structural Clay

Many domestic and foreign scholars have made a lot of theoretical andexperimental studies on pile foundation. However, the stress mechanism of pilefoundation is complex, settlement as one of the most important part in the designof pile foundation is affected by many factors, its theory and practice in the processstill have many deficiencies.Therefore, how to based on the comprehensiveunderstanding of the bearing mechanism of pile foundation and thesettlement characteristics of the reasonable design has become a problem facedby many scholars and engineering technicians. This article from the settlementcalculation theory and model test of two aspects of the Zhanjiang structural clay pilegroup settlement characteristics were studied in this paper, at the same time in orderto study the structural characteristics of Zhanjiang clay presented a more close to thearea of engineering settlement calculation method.The concrete work and mainresearch results are as follows:1.This paper first summarized the present vertical load of pilegroup settlement calculation theory and the overall situation of pile group modeltest research, and combining the key settlement characteristics summarized themain methods of settlement calculation of pile foundation and its advantages anddisadvantages.2.Design and complete the field test and indoor model test, the Q-S curve in thecomparison of sand and structural clay of Zhanjiang of nine pile model and solidfoundation that: when the load increases gradually, the structure of Zhanjiang soil isdamaged, the bearing capacity decreases rapidly until the loss of strength, the changeof the settlement in the sand increased significantly.3.By using variable depth shear spring constraint and full depth shear springconstraint solving the differential equation of composite elastic modulus andboundary conditions, the modified composite foundation model of equivalent piermethod in the specification, through the pile displacement in piece wise differential equation of full depth shear spring constraint model and combine with the boundaryconditions,a correction coefficient is proposed.The pile body compressionmodulusEPof pile group of E method is modified by considering the pile-soilload sharing ratio, the pile and soil as a whole to analyze the settlement of pilebody,compared with the traditional area replacement ratio considering factors morecomprehensively and respectively.4.Adopting the modified equivalent pier method,the modified equivalent piermethod considering the method of E to solve modulus,the equivalent pier methodconsidering modified composite elastic modulus three kinds of methods to calculatethe settlement of the actual project, through four sets of data to verify the correctnessand feasibility of the method proposed in this paper.