南京河西地区软土压缩蠕变特性试验研究

Experimental Study of Compression Creep Property of Soft Soil in Hexi Area of Nanjing

研究软土的压缩蠕变规律对于软土地区各类建筑物的长期稳定性和运行安全性十分重要.利用单向固结仪,进行不同荷载条件下南京河西地区软土压缩试验,获得了软土在单向压缩条件下应力与应变关系及应变与时间关系,试验结果表明:南京河西地区软土在单向压缩条件下的应力应变关系可用双曲线函数进行模拟,并且可用割线模量法概化应力应变关系;此外根据不同加荷条件下的蠕变试验结果,得出南京河西地区软土具有非线性蠕变特性;可用对数函数描述软土蠕变规律.研究结果可为南京河西地区软土地基的沉降和工后沉降计算提供依据.

Research into the impact of compression creep law of soft soil on long-term stability and running safety of buildings in soft soil areas is of great importance. Compression and creep tests in different loading conditions in Hexi Area of Nanjing are conducted by using unidirectional odometer. The relationship between stress and strain and that between strain and time are obtained. The test results show that the relationship between stress and strain of soft soil in this area under the condition of one-dimensional compression can be modulated by hyperbolic function, and this relationship is generalized by means of secant modulus method; in addition, the soft soil creepg nonlinear feature is remarkable according to the creep test results in different loading conditions, and the creep laws of soft soil can be described by means of logarithmic function. The resuhs can provide guidance for the calculation of settlement and settlement after construction of soft soil foundation in Hexi area of Nanjing.