斜拉桥纵横双向大悬臂0号节段施工技术概述

Construction Technology for Segment No.0 of Longitudinal and Lateral Cantilever of a Cable-stayed Bridge

重庆双碑嘉陵江大桥0号节段长25m,宽32.5m,重2600多t。其横桥向斜腹板形成两侧悬臂达11.75m,顺桥向悬臂为8.05m,节段单向悬臂重超过600t,相对于索塔墩,0号节面形成双向大悬臂、高悬空、大吨位的复杂条件。采用化繁为简、分段施工、托架与悬浇挂篮相结合的施工方法,即将双向大悬臂的0号块划分为两次施工:第一次由托架施工中段12.4m;第二次利用基本成形的挂篮,增设临时斜拉索,施工两侧各6.3m段。该方案从托架复杂程度和节段重量上,均大幅简化,投入措施数量少、成本节省、安全风险小,具有较好的经济效益。

Shuangbei Jialingjiang River Bridge in Chongqing has the segment # 0 of 25m long, 32.5m wide and over 2600t heavy, its transverse inclined slab forms the lateral cantilever of 11.75m, the prograde cantilever of 8.05m, unidirectional segment cantilever of over 600t heavy, and, compared with cable tower, segment # 0 forms the complex conditions of bidirectional cantilevers, high levitation and large tonnage. The construction methods of sim-plification, section, combination of bracket, cantilever casting and hanging basket are adopted, that is, to divide the construction of segment # 0 of the bidirectional cantilever into two phrases, the first for middle bracket section of 12.4m, and the second for the lateral section of 6.3m of the added tempo-rary stay cable based on the established hanging basket. This plan is simplified and has low cost, low risk and good economic profits.