南京长江三桥主塔墩基础大型双壁钢套箱施工测量技术

Construction Surveying for Big Double-wall Steel Float Caisson of Main Tower Pier Foundation of Nanjing No.3 Yangtze River Bridge

全面阐述了南京长江三桥南主塔墩基础大型双壁钢套箱施工过程的测控技术 ,针对大型双壁钢套箱的特殊结构形式 ,研究了初步定位和精密定位的方法。采用三角形斜边量距法 ,有效地解决了水上浮动状态下钢套箱的接高难题和倾斜度等多项指标的控制 ,并论述了钢套箱精密定位特征点的找寻及钢护筒精密定位的方法等。

This paper expounds the technique of surveying control during construction period of the big double\|wall steel float caisson of south ern tower pier foundation for Nanjing No.3 Yangtze River Bridge.Based on the spe c ial structural style,the method of the preliminary positioning and precise posit ioning of the big double\|wall steel caisson are studied.By the method of triang le bevel distance measurement,the puzzle of heightening steel float caisson on t he float condition above the water has been effectively settled,and the indexes, such as inclination pitch can be well controlled.Meanwhile,the location of chara cteristics points for precise positioning of steel float caisson and the method for precise positioning of the steel protecting tube caisson are discussed.