地铁重叠隧道盾构下穿拱桥数值分析

Numerical analysis of metro overlapping tunnel shield crossing arch bridge

以地铁重叠隧道盾构下穿某下承式实腹连拱桥为例,针对重叠隧道和实腹连拱桥的特点,对盾构下穿该拱桥的施工阶段进行数值分析,结果显示未加固工况下盾构下穿该拱桥时不满足变形控制及应力标准,提出在两个桥台背后各打设两排管棚,在桥墩底部进行袖阀管注浆加固,同时对全桥桥拱进行钢筋混凝土支撑的措施,并对该加固方法进行数值模拟,结果显示该加固方法满足变形控制及应力标准,为地铁重叠隧道盾构下穿某下承式实腹连拱桥提供了依据。

Taking the subway overlapping tunnel shield passing through a through solid web multi arch bridge as an example,according to the characteristics of overlapping tunnel and solid web multi arch bridge,the construction stage of shield passing through the arch bridge is numerically analyzed.The results show that under the unreinforced working condition,the shield passing through the arch bridge does not meet the deformation control and stress standards.It is proposed to set two rows of pipe sheds behind the two abutments,the sleeve valve pipe grouting reinforcement is carried out at the bottom of the pier,and the reinforced concrete support is carried out for the arch of the whole bridge.The numerical simulation results show that the reinforcement method meets the deformation control and stress standards,which provides a basis for the subway overlapping tunnel shield to pass through a through solid web multi arch bridge.