岩石断裂韧性与声波速度相关性的试验研究

EXPERIMENTAL STUDY ON THE RELATIONSHIP BETWEEN ROCK FRACTURE TOUGHNESS AND ACOUSTIC VELOCITY

陈治喜 陈勉 金衍

Chen Zhixi Chen Mian Jin yan

石油大学北京石油工程系

断裂力学是水力压裂研究的重要组成部分,在现有水力压裂模拟模型的基础上,提出了一个对空心厚壁圆柱形岩样施加内压而测定岩石断裂韧性的简单方法,并对部分砂、页岩试样进行了测试;建立了岩石断裂韧性与声波速度和动态弹性模量之间的关系,认为岩石的断裂韧性与纵波速度、横波速度和动态弹性模量有较好的线性相关性,为利用油井测井资料预测深部地层岩石断裂韧性打下了基础。

The fracture mechanics is important one of hydraulic fracturing study. Basedon the current hydraulic fracturing model, this paper proposes a simple method for determining the rock fracture toughness, which consists of hollow thick wall cylinder core with internal hydraulic pressure. A preliminary set of experiments has been performed on sandstone and shale. The relationships among rock fracture toughness, acoustic velocity and dynamic elasticity modulus have been established. Results show that fracture toughness has a good linear correlation with longitudinal wave velocity, shear wave velocity and dynamic elasticity modulus, It lays a foundation for predicting rock fracture toughness by using logging data from field.

10.3969/j.issn.1000-7393.1997.05.013