页岩弹性模量的预测方法研究

Research on the Prediction Methods of Elastic Modulus of Shale

页岩的弹性模量对于岩石工程具有十分重要的意义,但由于页岩是典型的横观各向同性岩石,这为预测其弹性模量带来了较大难度。常用的页岩弹性模量的预测方法为Niandou模型,但是该模型方程的形式较复杂,参数确定较为繁琐。本文针对页岩弹性模量的各项异性,提出了一种较为简易的线性经验模型。结果表明:本文提出的经验模型比经典的Niandou模型的方程形式较简易,所需的弹性参数较少,能够随着层理夹角的变化预测弹性模量;经验模型较Niandou模型整体平均误差略小,预测效果较好;尤其当层理面与加载方向的夹角为15°、30°和75°时,经验模型的预测相对误差更小,准确率较Niandou模型更高。

The elastic modulus of shale is of great significance for various projects.However,shale is a typical transversely isotropic rock,and predicting its elastic modulus is challenging.The commonly used method for predicting the elastic modulus of shale is the Niandou model,but the equation form and parameters determination of this model is complicated.Taking account of the anisotropy of elastic modulus of shale,in this paper a simple linear empirical model was proposed.The results show that the proposed empirical model which can predict the elastic modulus with the change of the bedding angle,is simpler than the classical Niandou model and requires less elastic parameters.For the proposed empirical model,the average relative error between the predicted value and the measured value is slightly smaller.Especially when the angle between the bedding plane and the loading direction is at 15°,30°and 75°,the accuracy is higher than that of the Niandou model.