摘要
针对老桥改建中应尽量利用老桥结构作为施工临时设施的原则,以上海杭申线航道等级提高而需要改建的一座桥梁为例,对大跨径钢-混凝土组合梁在老桥改建中的应用进行分析。结合该桥水中主桥的建设条件,经方案比选确定采用2×75m钢-混凝土组合结构连续梁桥作为改建方案,该方案可利用老桥桥墩分段安装组合梁桥的钢梁部分,先简支后连续,再以连续钢梁作为支撑体系施工混凝土桥面板,因而具有明显的技术经济优势。采用"能量法"优化施工措施以调整组合结构内力以及对负弯矩区混凝土桥面板裂缝进行有效控制的关键技术。在此基础上对大跨径组合梁在老桥改建中的应用前景进行展望,提出类似条件下将组合结构应用于改建的连续梁桥或索承式桥梁的加劲梁时较传统预应力混凝土结构具有明显优势。
On the principle that the existing bridge structures should be possibly used as the temporary construction facilities in reconstruction of the existing bridges, an existing bridge over the Hangzhou-Shanghai Ship Channel in Shanghai that was in need of the reconstruction because of the improvement of the ship channel was taken as an example and the application of the long span steel and concrete composite girder to the reconstruction of the bridge was analyzed. With refer- ence to the reconstruction conditions of the main bridge of the bridge over the river and through comparison of the different schemes, it was determined that the scheme of the 2 ×75-m span steel and concrete continuous composite girder should be chosen as the scheme for the reconstruction. In the scheme, the piers of the existing bridge could be used for installing the steel girder part of the composite girder in segments. The steel girder was simply supported first and made continuous late. The continuous steel girder was then used as a kind of the support system on which the con- crete deck slabs were to be laid and the reconstruction of the bridge in such a way exhibited signifi- cant technical and economic advantages. The construction measures were optimized, using the ＂en- ergy method＂, for the purpose of adjusting the internal forces of the composite structure and effec- tively controlling the concrete deck slab cracking in the negative moment areas. On the basis of the analysis of the reconstruction of the bridge, the application vistas of the steel and concrete compos- ite girders to the reconstruction of existing bridges were eventually prospected and in comparison to the application of the conventional prestressed concrete girders, the significant advantages of the application of the composite girders to the reconstruction of the continuous girder bridges the stiffening girders of the cable-supported bridges under the similar conditions were pointed out.
出处
《桥梁建设》
EI
CSCD
北大核心
2016年第1期59-64,共6页
Bridge Construction
关键词
老桥改建
钢-混凝土组合梁
方案比选
结构设计
施工措施
应用展望
existing bridge reconstruction
steel and concrete composite girder
scheme comparison
structural design
construction measure
application prospecting
