高温后大理岩各向异性响应特征研究

Anisotropy Response Characters of Marble After High Temperature

通过对含层理大理岩开展经历不同温度后的纵波波速测试试验,分析高温作用后大理岩纵波波速的变化规律,在此基础上探讨各向异性指数(平行与垂直层理方向波速比值)的变化趋势,研究温度对大理岩各向异性的影响规律。研究结果表明:经历高温后大理岩纵波波速下降,而且随经历温度的升高,大理岩纵波波速持续降低;大理岩纵波波速存在层理效应,主要表现为平行层理方向的波速大于垂直层理方向波速,各向异性指数为1.11~1.19;在30~200℃范围内,大理岩各向异性指数随温度呈现出两边低中间高的"倒U"形变化规律。研究成果在一定程度上反映了经历高温后岩石各向异性的变化,为预测和评估高温工程围岩的长期稳定性和安全性提供理论基础。

Longitudinal wave velocity test after different temperature of marble with bedding were done, the transformation law of mar- ble longitudinal wave velocity variation after high temperature, anisotropy index （ wave velocity specific value in parallel and vertical direction of bedding） were discussed based on it. The influence law that temperature to marble were studied. The results showed that marble longitudinal wave velocity decreased after high temperature, and with temperature increased, marble longitudinal wave velocity decreased continue, bedding effect appeared for marble longitudinal wave velocity, the wave velocity along parallel direction was larger than along vertical direction, anisotropy index was 1.11-1.29, during temperature scope 30 -200℃, marble anisotropy index appeared ＇ reverse U＇ change law with temperature changed. The results reflected rock anisotropy variation after high temperature in some degree, it provided theory base for surrounding rock stability and safety of high temperature project.