摘要
利用抗爆模型试验和数值分析方法,研究锚固洞室在顶爆作用下的破坏形式及破坏过程。根据锚固洞室破坏模型试验,发现锚固洞室主要有:受拉破坏、剪切破坏、受压破坏和压剪破坏4种破坏形态。通过分析试验解剖图和应力波传播规律发现:爆炸应力波作用下,锚固洞室首先在拱顶锚固区发生"层裂"现象,在自由面附近有类似半椭圆拱岩石介质脱落;同时两侧容易形成"八"字型剪切裂纹,随着爆炸荷载强度增加,如果锚杆加固较弱会在洞顶产生局部坍塌,一旦锚杆加固较强就会发生从爆心至洞室整体坍塌。最后利用数值分析方法分析了洞室受力情况和塑性区发展过程,进一步探讨了锚固洞室在顶爆作用下破坏形式和破坏过程。
Based on model tests and numerical analysis, failure modes and process under top explosion are studied. According to the results of the model tests, the tunnels reinforced by rockbolts under top explosion have four kinds of failure modes, that is tensile failure, shearing failure, compressive failure, compressive and shearing failure. By analyzing the experimental profile and the propagation rules of stress waves, when the stress waves reach the surface of the tunnel, spalling failure will appear, which may make similar half elliptical rock mass peel off. Both sides of the tunnel produce cracks easily. With the increase of blast load, if the anchor reinforcement strength is weak, local collapse will appear, and once the intensity of anchorage zone is large, it will le.ad to collapse of the tunnel from spandrel to explosion center. Finally, in accordance with the action process of stress waves, the stress distribution and the development process of plastic zone, failure modes and process are further discussed through numerical analysis.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2015年第8期1381-1389,共9页
Chinese Journal of Geotechnical Engineering
基金
河南省科技攻关计划项目(142102210433)
河南省教育厅科学技术研究重点项目科技攻关计划(14A440003)
深部矿井建设省级重点实验室开放基金项目(2014KF-05)
关键词
地下工程
爆炸应力波
锚固洞室
破坏形式
破坏过程
模型试验
数值分析
underground engineering
explosion stress wave
rockbolt-reinforced tunnel
failure mode
failure process
modeltest
numerical analysis
