超近距穿越构筑物箱涵顶进施工沉降控制技术

Surface Settlement Control During Pipe-Roofing and Box-Culvert Jacking Passing Through Adjacent Constructions

吉林污水管线防护涵工程超近距穿越运营中的铁路及管廊基础。近距离穿越构筑物,沉降控制一直是施工难点。采用Midas有限元软件,按实际施工过程进行详细模拟,研究超近距穿越既有建筑设施,管幕箱涵施作时,地表及周边建筑设施的沉降规律及其控制技术。结果表明,箱涵轴线上方土体沉降与周边建筑沉降均可分为3个阶段。施工前期,沉降随顶进缓慢增长;施工中期,沉降随着顶进加速增长;施工后期,沉降趋于稳定。根据分析,提出了不同阶段沉降控制措施。后期监测数据表明,管幕箱涵顶进施工过程中,轴线上方土体、管廊基础以及铁路线沉降均在控制值之内,保证了管廊和铁路正常使用与运营安全。

The pipe-roofing and box-culvert jacking project in Jilin province passed through adjacent constructions which were in regular service. By means of Midas finite element method, the research showed that there were three phases in the curve of surface settlement. In the first stage of the curve, the surface settlement increased slowly. As the project proceeded, it accelerated in the second phase. It ceased in the last phase. In contrast to the monitoring data, the curve of surface settlement was accurate, and useful to the project.