饱和状态下海积软土一维渗透固结特征试验研究  

Experimental Study on Permeability and One-dimensional Consolidation Characteristics of Marine Soft Soil under Saturated State

作　　者：叶朝良 谢玉芳[1] 曹风旭 王海强 YE Chaoliang;XIE Yufang;CAO Fengxu;WANG Haiqiang(School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Key Laboratory of Road and Railway Engineering Safety Control of Ministry of Education,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;China Ordnance Industry North Survey and Design Research Institute Co.,Ltd.,Shijiazhuang 050011,China)

机构地区：[1]石家庄铁道大学土木工程学院,石家庄050043 [2]石家庄铁道大学道路与铁道工程安全保障省部共建教育部重点实验室,石家庄050043 [3]中国兵器工业北方勘察设计研究院有限公司,石家庄050011

出　　处：《铁道标准设计》2021年第3期28-33,共6页Railway Standard Design

基　　金：国家电网公司总部科技项目(5204BB18001G);中铁十一局集团有限公司科研计划项目(50200010594)。

摘　　要：为研究连云港海积软土渗透固结特性,在室内开展其饱和重塑试样的物理性质、渗透、一维侧限固结等试验,在此基础上,讨论采用堆载预压法处理此类软土地基时的合理荷载值。结果表明:饱和重塑海积软土渗透系数与孔隙比呈指数关系,渗透系数对数与孔隙比呈线性关系;采用时间平方根法计算得到该重塑软土的固结系数为10^(-5)-10^(-4)cm^(2)/s,固结时间、固结压力和含水率对固结变形有显著影响,连云港海积软土的固结系数与固结压力统计关系可表达为Cv=Alnp-B;引入变形荷载比G这一概念,根据变形荷载比随固结压力的变化特征将曲线划分为3个区段,即理想区(0~50 kPa)、一般区(50~200 kPa)和欠佳区(>200 kPa);对于连云港海积软土,若只采用预压堆载法进行地基处理,经济合理的预压荷载宜在100 kPa左右。To study the permeability and consolidation characteristics of the marine soft soil in Lianyungang,some lab tests on physical properties,permeability and one-dimensional consolidation are carried out.On this basis,the reasonable pre-load of the soft soil foundation treated by surcharge preloading method is discussed.The results show that the permeability coefficient of saturated remolded samples is exponentially related to void ratio and the permeability coefficient logarithm tends to be linearly related to void ratio.Then Taylor’method is used to calculate the consolidation coefficient of samples,which indicates that in the range of 10^(-5)-10^(-4)cm^(2)/s,the consolidation pressure and water contend pose significant impact on consolidation deformation.The equation Cv=Alnp-B can be obtained by fitting datum of both the consolidation coefficient and pressure of soft soil with different water content.In addition,the characteristic curve of G(the ratio of deformation to load)with pressure is divided into three sections,i.e.ideal zone(0~50 kPa),general zone(50~200 kPa)and undesirable zone(>200 kPa).It is recommended that the reasonable pre-load should be about 100 kPa if only surcharge preloading method is used for treatment of the foundation.

关 键 词：海积软土 渗透系数 固结系数 变形荷载比 预压荷载 

分 类 号：TU411.4[建筑科学—岩土工程] TU447[建筑科学—土工工程]