世博轴及地下综合体的基坑工程设计

Excavation design of Expo axis and underground complexes

世博轴及地下综合体工程的基坑长约1000m,宽约100m,按基坑开挖深度不同分为三部分。地下两层区段开挖深度约12m,基坑保护等级为三级,采用重力式挡土墙或放坡结合800mm厚地下连续墙的边环板半逆作围护设计;地下浅三层区段开挖深度约为17m,基坑保护等级为三级,采用重力式挡土墙或放坡结合1000mm厚地下连续墙的边环板半逆作的围护设计;地下深三层区段开挖深度21.5m,基坑保护等级为二级,采用1000mm厚地下连续墙结合全逆作的围护设计。对各部分基坑给出了主要的监测结果。大尺度基坑的围护问题得到了安全经济的解决。

The excavation of Expo axis is about 1000 m in length and 100 m in width,divided into three parts according to the excavation depth.The 800 mm diaphragm wall with slope or cement-soil wall combined top-downwards basement construction with partial floors used as horizontal frame is used in B2 part with the excavation depth 12 m and the protection level 3;The 1000 mm diaphragm wall with slope or cement-soil is used in shallow B3 part with the excavation depth 17 m and the construction method is similar to that of B2 part;The 1000 mm diaphragm wall combined with top-downwards basement construction is used in deep B3 part with the excavation depth 21.5 m and the protection level 2.The field measured results are shown also.The problem of large excavation is solved economically and safely.