页岩声学参数与力学参数相关性的试验研究

用实验方法探讨了页岩的波速和衰减系数与抗压强度、弹性模量,泊松比的相关性。结果表明:1纵波波速建立的力学参数模型比横波波速模型的相关性要好;2除纵波波速与弹性模量模型的相关性较好外,纵波波速反演抗压强度、泊松比的误差较大;3纵波衰减系数与弹性模量、泊松比、抗压强度分别呈正相关指数、负相关线性和负相关多项式关系,且纵波衰减模型比波速模型的拟合效果好;4综合考虑波速和衰减系数建立的抗压强度模型、弹性模量模型、泊松比模型比单一因素模型反演精度更高,纵波波速和衰减系数。综合模型的相关性系数均大于0.85,完全能满足工程需要。其中横波的波速、衰减系数的抗压强度模型与纵波的波速、衰减系数模型预测结果相近,可用以验证纵波抗压强度预测效果。

EXPERIMENTAL RESEARCH ON THE CORRELATION BETWEEN ACOUSTIC PARAMETER AND MECHANICAL PARAMETER OF SHALE

The relationship between acoustic parameter and mechanical of shale are studied by using the experimental methods. The results show as follow: (1) The mechanical parameters model established by p-wave velocity have better correlation than established by s-wave velocity. (2) P-wave velocity model have good correlation with modulus, but cannot use to calculate Compressive strength and Poisson"s ratio (3) p-wave velocity model have better fitting effect than attenuation model, the relationship between attenuation coefficient and Elastic modulus, Poisson"s ratio, compressive strength are Positive correlation index, negatively correlated linearly and Negative correlation polynomial. (4) The compressive strength model, modulus of elasticity model, and Poisson"s ratio model established by velocity and attenuation coefficient have higher inversion accuracy than considering single factor. All correlation coefficients of integrated model are greater than 0.85, which full meet the engineering requirement. And compressive strength prediction result calculate by p-wave integrated prediction model is similar with the s-wave integrated prediction model, Therefore, we can use the s-wave integrated model to verify the accuracy of compressive strength prediction result