COUNTERMEASURES FOR DISASTER RECOVERY OF HIGHWAY FROM ZHANGMU TO YOUYIQIAO IN TIBET

The 3.0 km long highway from Zhangmu to Youyiqiao was destroyed by the mountain torrents and mud-rock flow in the upstream of Zhangmu town on July 5, 2016 after the "4.25" Nepal earthquake. In order to restore the highway as soon as possible, we conducted an in-depth research on the deformation history of Youyiqiao landslide group based on the monitoring data of deep displacement. It is concluded that the deformation rate of the landslide is closely related to the rainfall. The Youyiqiao landslide group is basically stable in the dry season. Its deformation starts with the increase of rainfall from June to July and intensifies in August. After entering September, the deformation converges rapidly with the decrease of rainfall. The earthquake, mountain torrent and mud-rock flow were the main inducing factors for the reactivation of landslides, and continuous rainfall intensified the activities of landslide group. Besides, in highway renovation, low frequency catastrophes would continuously threaten the highway with large-scale and ultra-deep landslides failed to be controlled permanently in a short term. So, we suggest that landslide control and highway traffic recovery should be our top priority currently, while in the long run, we should make further studies from policy-making in a macrocosmic sense relating to route selection along valleys and river banks.