粉土基质吸力的新型量测装置与土-水特征研究

Study of soil-water charactiristics and matric suction measurement device for unsaturated silty soil

以非饱和土张力计原理为基础,制作了一种新型的基质吸力量测装置,并通过实测过程的不断总结与改进,得到了一种成本低廉、制作简单、操作便利、试验快速和结果可靠的非饱和土基质吸力量测装置,以此装置测定了不同体积含水率、不同压实度和干湿循环后粉土的基质吸力变化规律,得到了不同压实度粉土的土-水特征曲线,并通过Origin软件中的Boltzmann模型进行拟合对比分析,得到了与压实度相关的土-水特征曲线,比较了不同压实度粉土的含水率变化对基质吸力的不同影响特点。试验结果表明,干湿循环对粉土的基质吸力和强度有很大影响。

Based on the principle for tensiometer to measure the unsaturated soil matric suction,a new matric measurment device was made.With continuously reviewing and improvment for the measurement result,the unsaturated soil matrix suction measurement device with more simple,convenient,fast and reliable advantages was achieved in the experiment.With this device,the matric suctions of silty soils with different water contends,different compactness or cyclic wetting-drying were measured;and the soil-water characteristic curves of silty soils with different compactnesses were obtained.Through the Boltzmann model in Origin sofeware to fit with the experiment curve,it＇s show that the influence for the water content to the matric suction was improved greatly by the high compactness,and cyclic wetting-drying influence the matric suction and shear strength of the silty soils greatly.