兰州某基坑加固抢险方案设计

Scheme Design on Foundation Excavation Strengthening in Lanzhou

兰州地区基坑开挖,常至黄土层、卵石层或泥岩层,因地下水作用,下部黄土层或泥岩层软化,基坑出现软根现象,极易造成局部塌方。通过工程抢险实例分析了其中原因,同时提出了抢险方案、施工设计的具体措施。实践表明,上部加设预应力锚杆、下部加设竖向微型钢管桩、木桩、加密网筋、加大混凝土体喷射厚度是兰州地区基坑抢险加固的有效措施。

The foundation in Lanzhou was always excavated to loess layer,cobble layer or marl layer.Because of underground water,loess or marl layer is easy soften,so landslide happen frequently in the foundation foot.By practical engineering,the authors analyze the landslide factors,and put forward emergency scheme and construction technology.The practical strengthen effect shows that some measures such as setting prestressed anchor in the upper and vertical mini steel pipe pile in the bottom,wood pile,densified steel bar mesh and thicken sprayed concrete are effective for strengthening foundation landslip in Lanzhou area.