上覆欠固结吹填粉砂深厚软黏土地基加固效果分析  

ANALYSIS OF THE VACUUM PRESSURE IMPROVEMENT EFFECT ON DEEP SOFT CLAY FOUNDATION COVERED BY UNCONSOLIDATED HYDRAULIC FILL OF SILTY SAND

作　　者：唐彤芝[1] 王海鹏[1] 孙国峰 柴犇犇 沈伟斌 

机构地区：[1]南京水利科学研究院,南京210029 [2]中交第三航务工程局有限公司宁波分公司,浙江宁波315200

出　　处：《工业建筑》2015年第10期111-115,137,共6页Industrial Construction

基　　金：中央级公益性科研院所基本科研业务费专项资金面上项目(Y314012)

摘　　要：通过对某上覆欠固结吹填粉细砂土深厚软土地基真空预压中真空压力传递和衰减、超静孔隙水压增长和消散、地基表面沉降、土体分层沉降变形特性和规律的分析,研究上覆欠固结吹填粉细砂土层对真空预压软基固结变形的影响。欠固结吹填粉细砂土层有利于下卧深厚软基的排水消压,地基沉降前期快、波动大,中后期收敛稳定快。膜下真空压力表面传递的差异性和波动性较大,向地基深处传递的滞后性和衰减幅度较大。欠固结吹填粉细砂土压缩量较大,吸收了大部分的真空能量,不利于下卧深厚软基的压缩变形。处理后欠固结吹填土的加固效果明显好于下卧软基土体。It was analyzed the law of the transmission and attenuation of vacuum pressure, the growth and dissipation of excess pore pressure, ground surface settlement, and the deformation characteristic and rules of layered settlement in the deep soft soil foundation covered by unconsolidated hydraulic fill of fine silty sand, and also studied the effects on consolidation deformation of the soft soil foundation covered by unconsolidated hydraulic fill of fine silt layer. Unconsolidated hydraulic fill of fine silty sand was conducive to the pore pressure dissipation and the drainage of underlying deep soft foundation.The foundation settlement was fast with fluctuation in the early stage, convergence and stability in the middle and later stage.When vacuum pressure under membrane transferred on the surface, its difference and fluctuation were large, when it passed to the deep foundation, its hysteresis and attenuation range was large.The compression of unconsolidated hydraulic fill of silty sand was large, and most of the vacuum energy was absorbed.The characteristic was not conducive to the compression deformation of underlying deep soft foundation. After treatment, the reinforcing effect of the unconsolidated hydraulic fill of silty sand was better than the underlying deep soft foundation.

关 键 词：吹填土 欠固结 软黏土 真空预压 加固 

分 类 号：TU472[建筑科学—结构工程]