西藏吉隆口岸G216国道K81特大型滑坡形成过程和机理分析

Formation process and mechanism analysis of the super large-scale landslide at K81km of the national highway G216 in Tibet Jilong port

受"4.25"地震影响,国道G216线K81km处发生特大型滑坡,通往尼泊尔的交通要道中断,抢险工作难以开展。为确保抢险保通顺利进行,推进灾后恢复重建,提升道路抗灾能力和口岸可持续发展,巩固西南边防,对G216国道K81特大型滑坡深入研究具有重要的政治和经济意义。通过地质勘察,以地质演化分析为基础,认识了滑坡的规模、性质及机理。分析认为,强震与地下水是滑坡的诱发因素,距坡顶高差约200m的滑塌体下落产生的冲击力是滑坡启动的必要条件。滑坡是由滑移—压致拉裂变形的岩质崩塌形成的崩坡堆积体演变而成的一个滑移—拉裂变形的碎石土滑坡。

Influenced by the ＂ 4. 25＂ earthquake,the super large-scale landslide occurred at K81 km of the national highway G216. The transport to Nepal was broken off,and it was difficult to carry out the rescue work. To ensure the smooth progress of the rescue,advance the post-earthquake recovery and reconstruction,improve road vulnerability and port sustainable development,and consolidate the southwest border,the study on the said landslide has important political and economic significance. On the basis of geologic analysis,authors realize the dimensions,nature and mechanism of the landslide through the whole reconnaissance of the geological hazard again. The earthquake and groundwater are the causative factors of the landslide,and the sliding body falling impact with about 200 m height is the necessary condition of landslide start. The landslide is a soil aggregate landslide which is evolved from the rock collapse whose deformation pattern includes the sliding and compression cracking. The failure mechanism of the soil aggregate landslide includes the sliding and fracturing.