The Inner Ring Rd Viaduct forms an important part of the fast viaduct network in Shanghai, but, with the rapid growth of downtown traffic, the demand is now more and more beyond its capacity. Studies are carried out on the feasibility, including comparison and selection of several proposals for widening the congested section of that viaduct.

本文通过外环线工程中钢-混凝土叠合梁桥的工程实例，介绍该种桥梁结构形式的设计步骤和计算方法以及主要的施工要求。