摘要
九江长江公路大桥主桥为六跨不对称混合梁斜拉桥,该桥九江岸南桥塔墩设置在长江永安大堤迎水面二坡道上,采用28根直径2.8m的钻孔灌注桩基础,左、右分离式承台。基础施工前,采取抛石固岸、设置防渗墙等措施防护大堤安全;采用冲击钻机钻孔,施工中采取多项措施保证钻孔质量;承台基坑开挖前采取支护桩+摆喷桩进行开挖防护,开挖后长江大堤设计枯水位以上坡面利用干砌混凝土预制块护坡,并对长江大堤二坡道平台进行混凝土封闭施工。实践证明,该桥南桥塔基础施工质量优良,经2010～2012年长江洪水季节考验,桥位处长江永安大堤稳固。
The main bridge of the Jiujiang Changjiang River Highway Bridge is a six-pylon a- symmetrical hybrid girder cable-stayed bridge. The foundation of the south pylon at the Jiujiang side is located on the slope way of the upstream surface of the Yongan Embankment in the Changjiang River, consisting of 28 bored piles with a diameter of 2.8 m each and the separated double pile caps upon. Before the foundation construction, the precautions of using riprap to strengthen the bank and building anti-pervading wall were taken to guarantee the safety of the embankment. The percussion type drill machine was used in hole-drilling and several precautiona- ry actions were taken to guarantee the quality of the hole. The method of using supporting piles plus pendulum jet grouting piles was adopted to safeguard the foundation pit excavation of the pile cap ahead of the excavation. Meanwhile, after the foundation pit excavation, the slope of the Changjiang River embankment above the designed low water level was paved by dry-laid precast concrete revetment, and the casting of the concrete was carried out on the platform of the slope ways of the embankment. The results show that the construction quality of the south pylon foun- dation of the bridge is excellent and the section of the Yongan Changjiang River embankment at the bridge site which withstood the flood season in the year 2010, 2011 and 2012 is proved to be sound.
出处
《世界桥梁》
北大核心
2012年第6期1-6,共6页
World Bridges
关键词
九江长江公路大桥
斜拉桥
桥梁基础
钻孔灌注桩
承台
设计和施工
Jiujiang Changjiang River Highway Bridge
cable-stayed bridge
bridge foundation
bored pile
pile cap
design and construction
