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近20年来,随着我国公路交通事业飞速发展,公路的等级不断提高,通车里程逐年攀升,公路建设已成为拉动国民经济增长的支柱产业和带动地方经济发展的龙头。在山岭和丘陵地区乃至越江过河的公路建设中,隧道方案以能缩短行车里程,提高线型标准、保障运营安全,保护生态环境等优点,得到普遍应用,并且越修越长,规模越来越大。许多特长隧道、
In the recent 20 years, with the rapid development of highway transportation in our country, the level of highways has been continuously increased and the mileage of open roads has been increasing year by year. The construction of highways has become a pillar industry that drives national economic growth and a leader in boosting local economic development. In the mountainous and hilly areas and even the river crossing the river highway construction, the tunnel program to shorten the mileage, improve linear standards, to ensure operational safety, ecological protection, etc., has been widely used, and the longer the repair, the more scale The bigger Many specialty tunnels,