Innovative laboratory testing
Innovative laboratory testing
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DOI：
10.1016/j.ijrmms.2004.09.008
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发表时间：
2004-12-01
影响因子：
7.2
通讯作者：
Chandler, NA
中科院分区：
文献类型：
--
作者：
Lau, JSO;Chandler, NA
开发了三种实验室测试技术，以研究和量化加载岩石试件的损伤发展，并为数值模型的校准和求解提供数据。损伤控制试验包括增量加载-卸载循环，体积应变反转时的应力(裂纹损伤应力σ(Cd))和每个连续循环计算的弹性性能。通过测量卸荷时的不可逆体应变以及岩石强度和弹性性质的退化来量化损伤。在长期加载试验中，对试件施加大于西格玛(Cd)的蠕变应力，直到破坏。破坏时间取决于蠕变应力与Sigma的比值(Cd)以及与围压的比值。结果表明，Sigma(CD)是岩石长期强度的合理估计值。通过周期性的卸载-再加载循环来测量弹性性能的退化来量化损伤。利用试验数据对Itasca的PFC应力腐蚀模型进行了标定。设计了五种类型的热松弹性试验，以确定模拟岩石热松弹性反应所需的九个热松弹性参数中的七个。试验是通过对岩样施加围压、温度或孔压的增量，并测量围压、试件体积和孔压的变化来进行的。五个参数的实测值与估计值吻合较好。(C)2004爱思唯尔有限公司。保留所有权利。
Three laboratory test techniques were developed to study and quantify damage development in loaded rock specimens and to provide data for use in the calibration and solution of numerical models. Damage-controlled tests involved incremental loading-unloading cycles with the stress at volumetric strain reversal (crack damage stress sigma(cd)) and elastic properties calculated for each successive cycle. Damage was quantified by measuring the irreversible volumetric strain upon unloading and the degradation of rock strength and elastic properties. In long-term loading test, a creep stress greater than sigma(cd) was applied to the specimen until failure. The time to failure was dependent upon the ratio of the creep stress to sigma(cd), and to confining pressure. It was shown that sigma(cd) is a reasonable estimate of the long-term rock strength. Damage was quantified by measuring the degradation of elastic properties through periodic unloading-reloading cycles. The test data were used for the calibration of Itasca's PFC stress-corrosion model. Five types of thermoporoelasticity tests were designed to determine seven of the nine thermoporoelastic parameters required for the modelling of the thermoporoelastic response of rock. Tests were performed by applying increments of confining pressure, temperature or pore pressure on the rock specimen, and measuring the changes in confining pressure, specimen volume and pore pressure. The measured values of five parameters were found to agree reasonably well with the estimated values. (C) 2004 Elsevier Ltd. All rights reserved.