一种测试不同温度下非饱和土土-水特征曲线的试验装置（英文）

A new triaxial apparatus for testing soil water retention curves of unsaturated soils under different temperatures

研究目的:研制一种试验装置,以实现对非饱和土土-水特征曲线温度效应的有效测试。创新要点:1.研制了一种温控非饱和土三轴试验装置,包括加载系统、吸力控制系统和温度控制系统;2.利用研制的温控非饱和土三轴试验装置,对不同温度(25,40和60°C)以及不同应力(40,100和200 kPa)条件下的非饱和土土-水特征曲线进行了试验测定。研究方法:1.总结分析已有的温控三轴仪所采用的加热方式的优缺点,提出环向加热压力室内水体的方法;2.基于GDS非饱和土三轴仪,研制可实现温度控制功能的温控非饱和土三轴仪(图1、2);3.开展不同温度及不同应力条件下非饱和土土-水特征曲线的试验研究。重要结论:1.所研制的温控非饱和土三轴仪的实用效果得到验证;2.温度的升高将引起非饱和土持水性能的降低。

This paper presents a new triaxial apparatus for testing soil water retention curves （SWRCs） under different temper- atures. The components of this modified apparatus, as well as the special features of each component, were described. The key part of this innovative apparatus was the temperature control system, which was cooperated with a loading system and a suction control system. Different methods of heating were compared and a more effective method, which used a heating element around the pressure chamber, was consequently adopted. Under different temperatures （25, 40, and 60 ~C） and different net mean stresses （40, 100, and 200 kPa）, typical results from the SWRCs tests for unsaturated silty clay were presented and analyzed. The experimental results show that the volumetric water content reduces with the increasing temperature at constant suction.