CAJ | 학술논문

采用三维有限元程序建立了一长为6 m、直径为0.8 m的加筋碎石桩复合地基流固耦合数值模型，分析了其在堆载和孔压消散过程中的荷载传递和变形特性。较传统碎石桩，加筋碎石桩复合地基桩土应力比显著增大，超孔压、沉降和桩身侧向变形显著减小，且随筋材刚度的增大，其性能进一步改善。加筋碎石桩复合地基在桩间土固结过程中产生明显的桩土差异沉降，形成土拱效应，使得堆载结束后桩土应力比变化很小。筋材长度对加筋碎石桩复合地基桩土应力比和沉降影响显著，应对其全长加筋才能保证桩体刚度和有效减少沉降。
채용삼유유한원정서건립료일장위6 m、직경위0.8 m적가근쇄석장복합지기류고우합수치모형，분석료기재퇴재화공압소산과정중적하재전체화변형특성。교전통쇄석장，가근쇄석장복합지기장토응력비현저증대，초공압、침강화장신측향변형현저감소，차수근재강도적증대，기성능진일보개선。가근쇄석장복합지기재장간토고결과정중산생명현적장토차이침강，형성토공효응，사득퇴재결속후장토응력비변화흔소。근재장도대가근쇄석장복합지기장토응력비화침강영향현저，응대기전장가근재능보증장체강도화유효감소침강。
A three-dimensional finite element seepage-coupling numerical modeling is performed on a 6m thick soft foundation reinforced by geosynthetic-encasement stone column (GESC) with diameter of 0.8 m. The load transfer mechanism and deformation characteristics of GESC composite foundation subjected to vertical loading and excess pore pressure dissipation are analyzed using the numerical model. Compared to conventional stone column (CSC) composite foundation, the stress concentration ratio (SCR) in GESC composite foundation apparently increases while the excess pore pressure, settlement and column shaft bulging apparently decrease. The performance of GESC is further improved with an increase of geosynthetic stiffness. An apparent differential settlement between column and surrounding soil emerges to form a soil arching during consolidation of the surrounding soil, which leads to little change in SCR values after loading. Reinforcement length is found to have a significant influence on SCR and settlement in GESC composite foundation. Full length reinforcement is required for GESCs in composite foundation to assure their entire stiffness and less settlement.