临崖巨型孤石与软弱围岩夹杂的大断面隧道进洞施工技术

Giant solitary rock and weak surrounding rock interspersed Construction Technology of Large Section Tunnel Entry Hole

为复杂地形地质条件下大断面隧道特殊进洞施工新思路,总结了南厦高速公路莲花隧道右线严重不均匀地质条件的施工经验。根据超前地质预报及超前探管探明隧道洞口巨型临崖孤石走向和深度,在避免大开挖、大爆破情况下,采用了长管棚挑起侵入隧道轮廓线内的巨型孤石、小导管注浆稳固洞口左侧滑坡面并网喷加厚混凝土反压土体,实现三维受力平衡的创新施工方案,实现了安全进洞。

In order to construct a large cross-section tunnel with special access under complex terrain and geological conditions,the construction experience of the right line of Lianhua tunnel of Nanxia expressway is summarized.According to the advanced geological prediction and the advanced exploration pipe,the direction and depth of the huge boulder near the cliff at the tunnel portal are verified.Under the condition of avoiding large excavation and large blasting,the long pipe shed is used to pick up the huge boulder and small pipe grouting which intrude into the tunnel contour to stabilize the landslide surface on the left side of the tunnel portal.The innovative construction scheme of three-dimensional stress balance is realized and the safety is achieved Hole.