When building bridges, it is beneficial to put the abutments close to each other to reduce the span as much as possible and steel sheet piles help make this easy to do. Another benefit of using sheet piling in bridge abutments and wing walls is speed. Steel sheet piles are also very good at preventing scour from becoming a problem.
Bridge abutments have two primary functions in bridge construction. One is to support the vertical loads of the bridge and the other is to act as a retaining wall for the soil that supports the roadway. Wing walls support the soil adjacent to the abutments.
Most bridge spans are dictated by the terrain or the road or stream they are crossing. When crossing streams and other water ways, it is usually easier to build the abutment away from the water so the contractor does not have to build temporary cofferdams. Building the abutments away from the water increases the bridge span which drives up the price. As spans increase, the moments increase as a function of the length squared and the deflections increase as a function of the length to the fourth power. If a bridge span is increased by 10%, the moments increase by 21% and the required stiffness increases by 46%. Using sheet piles to carry the vertical loads from the bridge and the lateral loads from the soil keeps the span short and keeps the construction quick and easy.