地铁隧道下穿单体多层建筑物评价方法
Evaluation method for multi-story buildings influenced by under-crossing metro tunnel
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摘要: 地铁隧道下穿建筑物实例越来越多,但下穿建筑物评价方法尚未统一。通过对实测隧道下穿建筑物变形规律分析,提出双线隧道下穿建筑物预测地基基础沉降,可以采用单线隧道已建立的北京Peck修正公式简单叠加。下穿建筑物评价时检测项目可以简化,建议仅以适当的外形测量、裂缝记录和无损探测等即可。下穿建筑物若为条形基础,其任意一段地基基础局部倾斜附加变形均应在控制值之内,已有局部倾斜较大地段为监测重点部位。提出评价地铁隧道下穿单体多层建筑物,可采取3个步骤:①找出其竣工图确认吻合;②进行现状测量和结构体表观检查检测,形成文件得以资料保存;③测定已有地基基础变形值,在总允许值中扣除之,即得隧道下穿建筑物允许附加变形控制标准。Abstract: With the development of urban metro construction, there are more and more under-crossing metro tunnels completed under buildings in Beijing. However, the evaluation method for the upper buildings influenced by under-crossing metro tunnels is not mature. Based on the analysis of the measured settlement of the upper buildings, following conclusions are drawn: (1) The settlement of the upper buildings influenced by double tunnels can be calculated by the superimposed modified Peck equation; (2) Only appearance measurement, crack record and non-destructive detection are necessary for the evaluation of the upper buildings; (3) The additional incline for any local part of strip foundation must be in the control range, and the area with large additional incline value should be highlighted in monitoring; (4) The evaluation of a upper multi-story building can be finished after three steps: a) The completion drawings of the building are used to confirm; b) The appearance measurement, structural detection and original documents are stored for preserving the evidence; c) By reducing the existing deformation of building foundation from the total allowable value, the additional deformation during construction period is given.