3D Numerical Simulation Study On Adjacent Pile Behavior Due To Un-braced Excavation Of Foundation Pit

In the introduction, firstly, the research status of passive piles are summarized,Especially the calculation method of the soil pressure along pile are roundlysummarized; secondly, distribution of displacement of pile and soil pressure are statedwhen the pile is established in the landslide or near load; thirdly, the relationshipbetween the soil pressure along pile and the relative movement of piles and soil aredeveloped by the author in two different kinds of soil; finally, the author sums up andanalyzes the research status of numerical analysis method to study the problem ofpassive piles, then expounds the importance and necessity of this paper.In the numerical simulation, first of all, A basic conditions is analyzed and thesimulation results is reasonable and credible by comparing the numerical simulationresults with foreign geotechnical centrifuge test results, on the basis of this, the authoranalyzes the influences of the pile bending moment and pile lateral soil pressuredistribution due to the variation of the restraint conditions; Then factors affecting thepile lateral soil pressure distribution and the pile bending moment are listed by author,such as the wall bending stiffness, pile length, pile bending stiffness, different distancebetween pile and wall, the axial load, and the author analyzes that these factors how toaffect it when the pile head is under the hinge branch and fixed conditions; The resultsshowed that the wall bending stiffness and different distance between pile and wall onthe influence law of pile lateral soil pressure and the bending moment is not affected bythe influence of pile head restraint condition, but pile length and axial load on theinfluence law of pile lateral soil pressure and bending moment is highly influenced bythe pile head restraint conditions; then, a simplified algorithm of estimating the pilebending moment is proposed by author in this paper, when the pile head is freedom,according to the pile lateral soil pressure distribution, the soil pressure of zero point isregarded as a hinge pedestal, pile is considered as a simply supported beam, which isverified to be feasible by some examples. The last, p curve model and factors thatinfluence the relationship p curve model are studied when the pile head is fixed and the hyperbolic model is more suitable under the condition of un-braced excavationin clay.