武汉软土次固结特性及其演变分析  

Analysis on Characteristics and Evolution of the SecondaryConsolidation of Wuhan Soft Soil

作　　者：张义德 孙红[1,2] 牛富俊 ZHANG Yide;SUN Hong;NIU Fujun(School of Naval Architectural,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Guangdong Provincial Key Laboratory of Modern Civil Engineering Technology,Guangzhou 510641,China)

机构地区：[1]上海交通大学船舶海洋与建筑工程学院,上海200240 [2]广东省现代土木工程技术重点实验室,广东广州510641

出　　处：《甘肃科学学报》2023年第6期85-91,共7页Journal of Gansu Sciences

基　　金：广东省现代土木工程技术重点实验室资助项目(2021B1212040003)。

摘　　要：软土的次固结变形是导致建筑设施缓慢沉降的重要原因。为研究武汉软土的次固结特性及其演变规律,对该地区的原状土应用分级加载方式进行多组一维次固结试验,分析荷载、超固结比以及试样结构性对该地区软土次固结特性的影响。采取公式推导、归一化处理、曲线拟合等方法研究次固结变形规律。试验结果表明:随荷载逐级增大,次固结系数(C a)先增大后减小。C a于先期固结压力附近达到峰值,试样天然结构被破坏;超固结比(OCR)越大,C a越小;受结构性变化影响,试样主次固结分界点有所不同。C a与压缩指数(C c)之比在试样天然结构性破坏前后分别为一定值。通过Power\,Allometricl两种数学模型分别迭代的方法,确定了幂函数-双曲线模型相关参数,结果显示模型能较好反映荷载大于100 kPa时试样的变形过程。The secondary consolidation deformation of soft soil is an important reason for the slow settlement of building facilities.In order to study the secondary consolidation characteristics and evolution rules of the soft soil in Wuhan,multi-group one-dimensional secondary consolidation tests were carried out by applying the graded loading method of the original soil in this area,and the influence of load and over-consolidation ratio on the secondary consolidation characteristics of the soft soil in this area was analyzed.Normalization treatment,curve filting and other methods were adopted to study the deformation law of the secondary consolidation.The test results show that the consolidation coefficient C a increases step by step with the load increase first and then decrease.C a reaches peak near the pressure of the early consolidation,and the natural structure of the specimen is destroyed.The larger the over-consolidation ratio,the smaller the secondary consolidation coefficient.Moreover,affected by the structural changes of the sample,the primary and secondary consolidation boundary points are different under different grades of pressurized load.The ratio of C a and compression index C c is a certain value before and after the natural structural failure of the sample.By Power and Allometricl,the power function-hyperbolic model related parameters were selected.The results show that the model can better reflect the deformation process of the sample when the load is more than 100 kPa.

关 键 词：武汉软土 结构性 超固结比 次固结系数 次固结模型 

分 类 号：TU447[建筑科学—岩土工程]