【摘要】 大跨连拱隧道受结构和跨度的影响 ,其初期支护与二次衬砌各自承受不同的围岩压力。通过计算分析 ,二次衬砌所受荷载比初期支护大得多 ,而且在初期支护与二次衬砌间存在不均匀压力 ,二次衬砌是主要承载结构 ,设计和施工时要合理掌握二者间的荷载分配比例更多还原

【Abstract】 Compared with single arch tunnel,large span and double arch tunnel has many deffrent characteristics,and there are pressures between it’s primary support and the second linning It is necessary to know the distribution portion of pressure on the first support and second linning when we design and construct such tunnels While insuring the effect of the first support,we must put into effect the second linning powerfully so as to insure the stability and safety of the tunnels更多还原