泥岩夹层软化试验研究

基于正交试验方案，研究了温度、卤水浓度及浸泡时间3个因素对泥岩夹层软化的影响规律。分别运用极差分析法和方差分析法对试验结果进行分析。对任意两个影响因素分别进行二元线性回归，根据其标准回归系数对泥岩夹层单轴抗压强度及弹性模量相对重要性比值构建判断矩阵，运用层次分析法计算各个影响因素的权值。试验结果表明：温度和浸泡时间在泥岩夹层软化过程中起着决定作用，影响权重达到98%以上；浸泡时间的影响最大，权重达到80%；卤水浓度的变化对泥岩夹层软化影响较微弱，在实际的工程中可以忽略不计。随着浸泡时间的延长和温度的升高，泥岩夹层内部裂隙逐渐被溶液侵入，单轴抗压强度和弹性模量呈递减趋势。鉴于卤水浓度影响甚微，仅利用温度和浸泡时间建立了软化方程。

Experimental research on softening in mudstone interlayer

Based on orthogonal test, the softening mudstone interlayer effected by three factors, i.e. temperature, brine density and immersion time, is studied. The extremum difference analysis and variance analysis are respectively applied to analyzing the results of the test. Any two factors are the binary liner regression; the relative importance ratio according to the standardized regression coefficients for the uniaxial compressive strength and elastic modulus of mudstone interlayer is used to build judgment matrix; analytic hierarchy process is used to calculate weights of various factors. The results show that the temperature and the immersion time play a decisive role on the softening process of mudstone interlayer; and the weights of analytic hierarchy process are more than 98%. The greatest influencing factor is immersion time whose weight is about 80%. The change of brine density has hardly any effect; therefore it can be neglected in the practical project. With the immersion time extending and the temperature increasing, the cracks in mudstone interlayer are gradually intruded into solution; meanwhile, the uniaxial compressive strength and elastic modulus show a decreasing trend. In view of the insignificant role the brine density plays in the whole experiment, only temperature and immersion time are taken into consideration to establish the equations.