西藏扎墨公路嘎隆拉隧道岩爆倾向性实验研究  

Test Study of Rockburst Proneness on Galongla Tunnel of Zhamo Highway in Tibet,China

作　　者：靳晓光[1,2] 王艳[1,2] 林志[3] 孙建国[3] 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]山地城镇建设与新技术教育部重点实验室(重庆大学),重庆400045 [3]招商局重庆交通科研设计院有限公司,重庆400067

出　　处：《山地学报》2013年第1期114-119,共6页Mountain Research

基　　金：西部交通建设科技项目(2007 318 740 04)资助~~

摘　　要：岩爆是高地应力山区硬岩隧道施工主要地质灾害之一,岩爆倾向性分析是研究、预测岩爆的主要方法。西藏扎(木)墨(脱)公路嘎隆拉隧道埋深大,地应力高,岩性主要为花岗岩,发生岩爆的可能性大。结合嘎隆拉隧道工程实践,在隧道钻取了岩芯试样,进行了岩石单轴压缩实验、单轴压缩加载和卸载实验以及Kaiser效应声发射实验,开展了岩爆倾向性研究。实验结果表明,岩石冲击性能指标WCF(峰值荷载以前的能量积累与峰后的能量耗散之间的比值)皆>3.0,大多数试样的弹性变形能指数WET(全应力—应变曲线峰值前区卸载曲线下面的面积与加卸载曲线之间的面积之比)>2.5,岩石具有强岩爆倾向;岩石声发射(AE)撞击数累计数-时间曲线特征属于第III类,当应力接近峰值时声发射突然迅速增大,岩石很快发生突然而猛烈的破坏,其岩爆倾向性强。隧道施工实践表明,在研究区段有岩爆现象发生,但由于地下水较发育,定为弱岩爆现象。岩爆倾向性研究为嘎隆啦隧道安全施工和支护设计优化提供了信息,也为西藏复杂地质条件下类似工程建设提供一定的借鉴。Rockburst proneness is one of main geologic disasters in the mountain construction of hard rock tunnel with high geostress, rockburst proneness analysis is the main method of studying and predicting rockburst. Galongla Tunnel of Zhamo Highway （from Zhamu to Motuo） in Tibet, which buried deeply with high geostress and whose main lithology is granite, has the high possibility of rockburst. Based on the Tibet Zhamo Road Galongla Tunnel Engineering, drilling the core specimens from Galongla tunnel, rock uniaxial compress experiments, rock uniaxial compress loading and unloading experiments and Kaiser effect acoustic emission experiments were done, carrying out the studying of rockburst proneness. The test results shows that the impact performance indicators Wcr （ the rati- o between energy accumulating before peak load and energy dissipation after it） are more than 3.0 all, most elastic deformation energy index W^r （ the proportion of the area under the unloading curve to the area between the loading and unloading curve in the pre-peak of the complete stress-strain curve） are more than 2.5, the rock has strong roekbust proneness. Characteristics of AE accumulation of hit number-time curve belongs to classⅢ, AE counts in- crease suddenly when the stress is near the peak, the rock has a sudden and heavily destroy quickly, whose rock- burst proneness are strong. The tunnel construction practice shows that there are rockburst happened in research section, but because of enough groundwater, it is designated as weak rockburst. The study of rockburst proneness provides information for safe construction and optimizing design of Galongla Tunnel, and provides reference to other similar projects in high geo-stress areas.

关 键 词：隧道 冲击能指标 弹性变形能指标 声发射特征 岩爆倾向性 

分 类 号：TU9[建筑科学] U45[建筑科学—桥梁与隧道工程]