Translation exercise: Lasi highway Corrections will be extremely appreciated, thank you.:) ------------------------------------------------------------------- General introduction about Lasi highway Lasi highway climbs up from the edge of Sichuan Basin to Hengduan mountain area along the south silk road. It goes through the deeply mountain valleys of southwestern China that natural geologic hazards frequently happen. The terrain conditions are extremely harsh, geologic structure is complicated, weather conditions are changeable, and the cological environment is extremely fragile. These factors make both the construction and operating safety under a lot of difficulties. Lasi highway is generally recognized by experts, as one of the mountain area highways that has the worst natural enviorment, the most difficult engineering, and the highest technology content in China even in the world. Lasi highway crosses over 12 seismic fault lines and rivers including Qiyi, Dadu and Anning. It passes through the mountains, every 1 km it stretches the average rise in elevation is 7.5 meters. Therefor it is called "the sky ladder highway", "the highway beyond the clouds". 55% of the highway consist of bridges and tunnels. There are total 270 bridges, among them 23 are extra-large, 168 are large. And there are 25 tunnels, including 2 extra-long and 16 long. 概况 雅西高速公路由四川盆地边缘向横断山区高地爬升，沿南丝绸之路穿越中国大西南地质灾害频发的深山峡谷地区，地形条件极其险峻，地质结构极其复杂，气候条件极为多变，生态环境极其脆弱，建设条件极其艰苦、安全营运难度极大，被国内外专家学者公认为国内乃至全世界自然环境最恶劣、工程难度最大、科技含量最高的山区高速公路之一。 雅西高速公路还跨越青衣江、大渡河、安宁河等水系和12条地震断裂带，整条高速公路线展布在崇山峻岭之间，山峦重叠，地势险峻，每向前延伸一公里，平均海拔高程就将上升7.5米，被称作“天梯高速”、“云端上的高速公路”。全线桥隧比高达55%，全线有桥梁270座，其中特大桥23座，大桥168座；有隧道25座，其中特长隧道2座，长隧道16座。