论文部分内容阅读
南京市栖霞区学林路东南端有一小段人工隧道(图1),长120米,顶高10米,隧道两侧是低缓的小山丘(相对高度20米),隧道顶部与山体表面都有茂密的植被覆盖,以亚热带常绿阔叶林为主。在坡度低缓的山丘间修建城市道路为何要采用隧道方案呢?直接把山体挖开,削低新鲜断面的坡度不就行了吗?实际上,图中隧道是在开挖山体后又建造的,并未采用传统山体基部掏空的方法,这显然增加了施工成本。为什么要这样做?
There is a short artificial tunnel at the southeast end of Xuelin Road in Qixia District of Nanjing (Figure 1), 120 meters in length and 10 meters in height. The two sides of the tunnel are gentle hills (20 meters in height) Of the vegetation cover to subtropical evergreen broad-leaved forest. Why do we need to adopt a tunnel scheme to build an urban road between the hills with gentle slopes? Do we need to dig the mountain directly to cut down the slope of the fresh section? Actually, the tunnel was built after the excavation of the mountain. The method of tunneling at the base of the traditional mountain is not adopted, which obviously increases the construction cost. Why do you want to do this?