武汉长江隧道公铁合建与分建的经济性对比分析

Comparative Economic Analysis of Highway-Metro Integrated and Separated Construction of Yangtze River Tunnel in Wuhan,China

为探究武汉长江隧道公铁合建与分建的经济性差异,选取4个武汉长江隧道为典型案例,首先简要介绍其相关工程实施方案,然后从工程组成部分、土建各项指标等方面,对武汉地区地铁过江隧道、公路过江隧道、公铁合建过江隧道3种模式下的土建投资展开对比分析,最后揭示公铁合建与分建土建费用差异的原因。分析结果表明:1)因断面利用率高,江中纯盾构段合建方案分摊的地铁盾构部分和公路盾构部分土建费用均低于分建方案;2)采用合建方案时,由于上部为公路、下部为地铁,造成明挖段基坑深度大,导致合建方案分摊的地铁明挖段和公路明挖段费用均较单建方案高;3)合建方案与分建方案土建总费用相当。

To investigate the economic difference between the highway-metro integrated and separated construction of the Yangtze river tunnel in Wuhan,China,four Yangtze river tunnels in Wuhan are chosen as typical cases.First,the case implementation strategies are briefly discussed.Next,a comparative analysis of the civil construction investment under three modes of metro Yangtze river tunnel,highway Yangtze river tunnel,and highway-metro integrated Yangtze river tunnel is performed in terms of project components and various indxes of civil construction.Finally,the causes for the difference in civil construction costs between the highway-metro integrated and separated construction are shown.The analysis results reveal the following:(1)The civil construction expenses of the metro and highway shield sections shared by the Yangtze river highway-metro integrated construction tunnel are cheaper than those of a separated construction tunnel due to the high section usage rate.(2)The upper highway and lower metro of the tunnel will cause great depth of opencut foundation pit,and further cause higher civil construction costs of the metro and highway sections shared by the opencut section of the high-metro integrated construction scheme than those of separated construction scheme.(3)The integrated and separated construction concepts have nearly identical total civil construction costs.