摘要
通过现场试验对比分析了钉形搅拌桩和常规搅拌桩复合地基的路中心分层沉降,并通过三维数值模拟分析了复合地基设计参数对路堤荷载下钉形搅拌桩复合地基沉降的影响。现场试验结果表明:相对于常规搅拌桩复合地基,由于扩大头作用和较高的桩身质量,钉形搅拌桩复合地基中更多的荷载通过桩体传递到下卧层,有效减小了加固区的沉降,但下卧层的沉降有所增加;由于下卧层土质较好,其地表总沉降小于常规搅拌桩复合地基。数值模拟结果表明:扩大头高度、桩长、桩间距和桩身模量是影响地表总沉降的主要因素;扩大头直径、桩间距和桩身模量是影响地表桩土相对沉降的主要因素,提高扩大头高度能有效减小地表总沉降;提高扩大头直径能有效减小地表桩土相对沉降。
Through comparative analysis of field test,layered settlement at road center of T-shaped deep mixed column composite foundation was analyzed.A 3D numerical simulation was conducted to analyze the influence of the design parameters on the settlement of T-shaped deep mixed column composite foundation under embankment load.Field test results indicate that the load transfers to the substratum through columns in T-shaped deep mixed columns composite foundation because of the enlarged column cap effect and higher column quality so that the settlement of improved area in T-shaped deep mixed column composite foundation is significantly less than the conventional one,while the settlement of substratum in the former is slightly lager than that in the latter.However,the total surface settlement of T-shaped deep mixed columns composite foundation is less than that of the conventional one because of the fine performance of the substratum.The simulation results indicate that enlarged column cap height,column length,column space and column modulus are the main parameters of effecting the surface settlement,while enlarged column cap diameter,column space and column modulus are the main parameters of effecting the differential settlement.Increasing enlarged column cap height can decrease the surface settlement,while increasing enlarged column cap diameter can decrease the differential settlement efficiently.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2010年第5期1-7,共7页
China Journal of Highway and Transport
基金
国家自然科学基金项目(50879011)
江苏省研究生科研创新计划项目(CX08B_101Z)
东南大学优秀博士论文基金项目(YBJJ0914)
关键词
道路工程
复合地基
现场试验
钉形搅拌桩
沉降
数值模拟
road engineering
composite foundation
field test
T-shaped deep mixed column
settlement
numerical simulation
