管棚支护下框架桥顶进设计和施工

郑州市金水路西延南半幅道路下穿金水路工程采用管棚支护路基、框架桥预制顶进的施工方法,控制路面沉降并顶进框架桥就位是项目成功实施的关键。采用有限元软件对框架桥顶进施工过程中路面的沉降进行模拟计算,分析路面沉降值及其规律。计算表明,顶进施工引起的路面沉降最大值约为13 mm,开挖影响范围约为工作面前方8~10 m,路基内设置吊梁和框架桥周围注浆措施可分别使顶进中路面沉降减少36.5%、7.4%。现场监测路面沉降规律和计算结果基本一致,工程采用的工法保证了项目的成功实施。

Design and Implementation of Jacking Frame Bridge Supported by Pipe Shed

The construction method of jacking frame bridge supported by pipe shed is adopted in Jinshui Road westward expansion project with south half road under-passing Jinshui Road. Controlling ground settlement and jacking the frame bridge to the designed location is the key to the successful implementation of the project. The ground settlement during jacking is simulated and analyzed with finite element software to calculate the value of ground settlement and find out the deformation law. The simulation results show that the maximum ground settlement is 13 mm,the affected area of excavation is about 8 ~ 10 m in front of the working face,and setting up hanging beams in the roadbed and grouting around the frame bridge can reduce settlement by 36. 5% and 7. 4% respectively during the jacking process. The monitored ground settlement is basically the same as the calculation result. The method adopted in the project ensures the successful implementation of the project.