What is the advantage of sliding bearings over roller bearings?

In roller bearing for a given movement the roller bearing exhibit a change in pressure centre from its original position by one-half of its movement based on David J. Lee.  However, with sliding bearing a sliding plate is attached to the upper superstructure and the moving part of bearing element is built in the substructure. … Read more

Why is the span length ratio of end span/approach span to its neighboring inner spans usually about 0.75?

From aesthetic point of view, an odd number of spans with a decrease in length in the direction of abutment is desirable. Moreover, spans of equal length are found to be boring. However, the arrangement of irregular span lengths is not recommended because it gives a feeling of uneasiness. From structural point of view, for … Read more

In the design of a simply supported skew bridge, which direction of reinforcement should be provided?

In the conventional design of steel reinforcement for a simply supported skew bridge, a set of reinforcement is usually placed parallel to free edge while the other set is designed parallel to the fixed edge. However, this kind of arrangement is not the most efficient way of placing the reinforcement. The reason is that in … Read more