黄舣长江大桥H型索塔下塔肢钢绞线对拉系统设计

Design of Counter-pulling system of Tower Limb Steel Strands under H-type Cable Tower on Huangyi Yangtze River Bridge

由于斜拉桥H型索塔下塔肢外倾,当施工到一定高度后,其内侧根部混凝土将产生拉应力。为了防止拉应力超过混凝土抗拉强度值后混凝土将出现破坏裂缝,故通常需要对拉2塔肢以消除该拉应力。以黄舣长江大桥4#高塔为例,介绍H型索塔下塔肢对拉设计的计算思路和要点,其也适用于内倾型塔肢进行钢管桩对撑计算。

Due to extraversion of tower limbs under H-type cable tower on cable-stayed bridge, concrete at its interior root will produce tensile stress when construction is up to a certain height. In order to prevent damage cracks on concrete after tensile stress is over tensile strength of concrete, usually counter-pulling of two tower limbs is required to remove this tensile stress. This paper, based on No. 4 tower on Huangyi Yangtze River Bridge, introduces computational ideas and key points in counter-pulling design of tower limbs under H-type cable tower, which are also applicable to counter-bracing computatiori of steel tube piles for introversive type tower limbs.