Steel bridge design and construction: a Southern African experience

Abstract

Bridge design and construction has gone through several phases in Southern Africa. The first phase was dominated by steel. During this phase, revolutionary steel bridges were constructed. This happened despite the fact that steel was not manufactured in this region. The use of structural steel in these bridges exploited its advantageous properties of economically carrying heavy loads over long spans with minimum dead weight. After this phase, the choice of material used in bridges changed to concrete. During the past 20 years, steel has staged a strong comeback. The aim of this paper is to explain why the bridge industry has experienced different phases in construction. Selected case studies of vehicle and foot steel bridges are presented and discussed to substantiate the competitiveness of steel as a bridge construction material.