The Anti-liquefaction Mechanism And The Evalua-Tion Of Masking Effect Of The Composite Foundation Of Gravel Pile In A-karoad

With the implementation of the western development strategy in China and the increases demand of road transport,there appears a large number of new western highway construction.The western China as a high seismic region,its safety would face great threats when devastating earthquake occor.Since gravel pile foundation is one of the effective anti-liquefaction treatment measures,the research on gravel pile composite foundation anti-liquefactionmechanism and its evaluationcould be believed has important meaning in highway engineering design and safety assessment.Based on theissue of anti-liquefaction detect on Akaroadconstruction,which used dynamic compaction to deal with the liquefaction foundation,two kinds of anti-liquefaction treatment schemes for deep liquefaction foundation are proposed in this paper.Then,this paper use the measured of elastic-plastic numerical analysis to evaluat the dynamic consolidation of two kinds of anti-gravel pile in liquefaction ground liquefaction mechanism and the shielding effect.Finally,theresults and project investment value based on the cost of the case,to determine an economically rational foundation anti-liquefaction treatment scheme.The main results are as follows:(1)Based on theissue of anti-liquefaction detect on Aka road construction,this study combined the characteristic that the situation of deep soil liquefaction case on Aka Highway AK-3 bid section,first proposed anti-liquefaction treatment scheme based on dynamic compaction and gravel pile to treat deep foundation,then raised edge Minister pile,piling gravel pile central processing processing program deep liquefaction foundation.(2)Used a more comprehensive theoretical framework of elastic-plastic dynamic consolidationapproach to study the reinforced gravel pile composite foundation under earthquake action response characteristics.Based on Pastor-Zienkiewicz ? Generalized plastic constitutive model of unsaturated soils between solid and liquid body coupled dynamic consolidation theory,this study analyzed the seismic acceleration of the natural foundation,composite foundation under different conditions and other deep foundations,dynamic pore water pressure and displacement dynamic response,and thenproposed that the long pile around gravel pile has a certain shielding effect to the deep liquefaction of foundation.(3)For dynamic consolidation foundation treatment,dynamic compaction and long-short-pile composite foundation,by the calculation of quantities of these three schemes and investment cost comparison and according to the numerical results and comprehensive evaluation of the project investment costs,this paper confirmed the programof gravel pile which deal with the deep liquefied foundation at both ends set the long pile,the middle set short pile.This program can not only ensure the safety of Aka highway embankment in case ofearthquake,but also take full advantage of the long pile for shielding effect liquefaction exists,at the same time it can greatly reduce thecostsof anti-liquefaction project.Therefore,measures to deal with the deep liquefied foundation,long-short-pile composite foundation of gravel pile is an effective,economical and reasonable anti-liquefaction treatment program of measures,and it could be believed as a good application prospects in the future.