既有跨河公路桥上新建高架桥的基础施工

Foundation Construction of New Viaduct on Existing River Crossing Highway Bridge

新建跨金清港高架桥与既有麻车大桥线路重合,所处金清港航道等级较低,且需保持通航,原有麻车大桥承载能力较低,其桩基础位于既有麻车大桥中央隔离带及两侧,距航道、高压线近,施工环境均无法保证大型机械起重方案的应用。灌注桩桩径3.2m,最大成孔深度88m,新建高架桥的桩基施工困难。论文提出了一种新的起重吊装方案,并介绍了在既有跨河公路桥上新建高架桥的基础施工工艺,在工程中得到了成功应用。

The newly-built viaduct crossing Jinqinggang overlaps with the existing Mache bridge,which is located in the lower grade of jinqinggang channel and needs to be navigable.The bearing capacity of the original Mache bridge is relatively low.Its pile foundation is located in the central isolation zone and both sides of the existing Mache bridge,which is close to the channel and high-voltage line,so the construction environment can not guarantee the application of large-scale mechanical lifting scheme.The diameter of cast-in-place pile is 3.2m,and the maximum hole forming depth is 88m,and the pile foundation construction of new viaduct is difficulties.This paper puts forward a new hoisting scheme,and introduces the foundation construction technology of the new viaduct on the existing river crossing highway bridge,which has been successfully applied in the project.