土体在大气作用下吸力变化特征

自然界土体的力学特性随大气的变化而变化,本文目的就是探讨在大气作用下,土体吸力变化规律。对于土体的温度和吸力变化特征,采用Wilson提出的理论加以描述,在此理论中,分别利用Darcy和Fick定律描述水和蒸汽的流动规律,土水特征曲线和水力传导系数假定仅仅相关于非饱和土吸力,水的潜热系数是温度的线性函数,温度传导系数采用De Vries建议方程加以计算。文中考虑降雨、温度和风速等不同因素对岩土孔隙介质力学性质的影响,并利用Penman方程估算水的蒸发率。该理论被利用来模拟法国Boissy现场实测结果,其理论结果和现场实测结果是较一致的。

Variation of suction of soil under atmosphere

It is well known that the atmosphere exerts influence on mechanical properties of soil.The aim of this paper was to investigate the factors influencing climate.The theories proposed by Wilson(1994) were adopted to describe the fundamental behaviors of temperature and variation of suction of soil.The Darcy’s law and Fick’s law described the flows and evaporation of water respectively.Some proposed assumptions including the characteristic curve of volumetric water content and hydraulic conductivity were only related to the suction of unsaturated soil.The coefficient of latent heat for water was a linear function of temperature;and the heat conductivity was calculated according to the equation proposed by De Vries.The influence of climate factors was also studied by considering rainfall,temperature and wind speed,and the evaporation rate was evaluated by Penman’s equation.The above theory was adopted to simulate the in-situ results of Boissy in France,and the numerical simulation showed that the theoretical and monitored results were in good agreement.