浅埋偏压连拱隧道开裂原因及防治措施

双连拱隧道施工工序复杂,致使围岩应力发生多次重新分布。尤其在浅埋、偏压情况下,如果施工工序不合理,必然导致衬砌裂缝的出现。以铜黄高速公路汤屯段富溪隧道为背景,指出偏压荷载、地下水和不合理的施工工序是裂缝产生的主要原因。根据不同成因,分别采用设置挡土墙、地表排水、注浆加固、先施工浅埋侧等方法进行处理。

Study on the Crack of Double-Arc Tunnels and Its Prevention Measures

The complex construction procedure of double-arc tunnels often leads to redistribute of rock strain. in the condition of uneven pressures and shallow buried, improper construction procedure may also cause cracking in tunnel supporting and lining. Based on the engineering of Fuxi tunnel, the main factors of cracking of tunnel supporting are analyzed. It is found that the uneven pressure, underground water, and improper construction sequence are the main causes for the cracks of double-arc tunnel. In order to treat the cracks of tunnel, some measures have been adopted, such as supporting the slopes of tunnel, reinforcing the ground surface, grouting in tunnel, excavating the shallow side of tunnel.