Optimal ratio of spans of continuous bridges

Abstract

The article deals with the creation of continuous metal and monolithic reinforced concrete bridge spans, which are the most effective. Efficiency is achieved by finding opportunities for the unification of structures with the most successful options for providing them with the required load-bearing capacity with the lowest cost of building materials. The bending moments that occur in the sections of a continuous structure are distributed more evenly and take on smaller values in the span than in a split structure. However, the efficiency of continuous structures can be further improved by introducing a certain coefficient of the length of the extreme spans of the bridge relative to the average ones. This allows you to achieve equality of the reference or span bending moments. As a result, the design will work in such a way that it will be possible to build the bridge span as if from three types of unified blocks, which will reduce the complexity and cost of construction work. As an example, in this case, the ratio of spans and the corresponding division into blocks for four-span continuous bridges are determined.