不同温湿环境下泥岩吸水及膨胀特性的试验研究

Experimental Study on Water Absorption and Expansion Characteristics of Mudstone under Conditions of Different Temperature and Humidity

现场取南昌市轨道交通二号线龙岗站泥岩,试验室内对其切割、打磨,将泥岩置于不同温度梯度环境下(相对湿度RH>95%):常温,35,40,45℃,研究不同温湿度条件下,泥岩吸水特性及膨胀特性的规律。试验结果表明:泥岩在不同的温湿环境下吸水曲线可分为3个阶段:剧烈吸水阶段、减速吸水阶段、吸水平衡阶段;吸水量、吸水速率均与温度呈线性相关。泥岩在不同温湿环境下膨胀曲线也可分为3个阶段:应变加速阶段、应变减速阶段、应变稳定阶段;随着温度的升高,轴向膨胀率随之增加,膨胀速率随随之加快,达到膨胀稳定的时间随之延长。轴向膨胀率、膨胀变形速率均与温度呈线性相关。

Mudstones were sampled from Longgang station of Nanchang Metro Line 2 and were cut as well as ground in the laboratory in this study. Then it explored the water absorption and expansion regularity of mud- stones under different temperature and humidity conditions （relative humidity RH〉95%）, namely the normal tem- perature, 35℃,40℃,and 45℃. The test results showed that the water absorption curve of the mudstones can be divided into three stages under different temperature and humidity conditions：severe water absorption phase, the deceleration phase of water absorption and water absorption equilibrium phase;water absorption and water absorption rate were linearly correlated with temperature. The expansion curves of mudstones under different hy- grothermal conditions can be divided into three stages：the strain acceleration stage, the strain deceleration stage, and the strain stabilization stage. With the increase of temperature, the axial expansion rate and the acceleration rate of expansion increased and the time of reaching the steady expansion was prolonged. It maintains that the temperature is linearly correlated with the axial expansion rate and expansion deformation rate.