Damage evolution in strain weakening rocks

应变弱化岩石中的损伤演化是强度逐渐或快速丧失，最终导致破裂。 在地下岩石工程中，这种脆性破坏过程通常被称为剥落。 随着地下挖掘深度的增加，以及在300至700 m深度处建造地下核废料处置隧道的建议越来越接近现实，这种形式的脆性破坏变得相当重要。 通过广泛的实地监测，主要是在专门的地下研究设施进行核废料地质处置，在了解岩体中这种破坏过程的开始方面取得了重大进展。 在这些发现的基础上，申请人提议开展一项研究计划，旨在开发遇到这种形式的故障时的隧道设计方法。 研究结果将由加拿大、瑞典、芬兰和瑞士的核废料机构使用精心控制的现场实验进行评估。

Damage evolution in strain weakening rocks is a gradual or rapid loss of strength that ultimately leads to rupture. In underground rock engineering this brittle failure process is commonly referred to as spalling. As the depths of underground excavations increase, and the proposed construction of underground nuclear waste disposal tunnels at depths of 300 to 700 m moves closer to reality, this form of brittle failures is taking on considerable importance. Significant progress has been made in understanding the initiation of this failure progress in rock masses, through extensive field monitoring, mainly at dedicated underground research facilities for the geological disposal of nuclear waste. Building on these findings, the applicant proposes to undertake a research program aimed at developing a methodology for tunnel design when this form of failure is encountered. The results from the findings will be evaluated using carefully controlled in-situ field experiments by nuclear waste agencies in Canada, Sweden, Finland and Switzerland.