一种岩心样品横波速度的实验室测量方法

A method of testing the S-wave velocity of the core samples in laboratory

准确测量声波在不同类型岩心中的传播速度是岩心声学性质分析的基础。一般实验室利用超声波透射法所测试的岩心样品均为小尺寸岩心样品。在测量小尺寸岩心样品横波波速时,难以消除的纵波余震信号会对横波的识别产生干扰。提出了一个在实验室内测量小尺寸岩心样品中横波波速的"辅助块"超声波透射波测试方案,较好地实现了纵横波的分离,减小了横波波速的测量误差,提高了岩心样品横波波速测试的精度。给出了上述测量方案和测量实例分析,该方法亦可用于一般固体样品中横波波速的测量。

Accurate measurement of the ultrasonic in different types of cores is the basis for the analysis of the acoustic properties of the core. In general, the core samples used for the ultrasonic transmission test in laboratory are small-sized core samples. When measuring the S-wave of the small-sized core sample, the aftershock of the compres- sion wave, which is hard to be eliminated, may interfere with the recognition of S-wave. In this paper, a method of adding an ＇auxiliary block＇ in the transmission ultrasonic wave test is provided for measuring the S-wave velocity of the small-sized core samples in laboratory, with which the compression and shear waves can be effectively separated to reduce the measuring error of the S-wave velocity in the core sample and to improve the test accuracy. This paper presents the measuring programme mentioned above and makes the analyses of several test examples. This me- thod can also be used for measuring the S-wave velocities in general solid samples.