The Performance of Integral and Semi-integral Pre-tensioned Concrete Bridges Under Seismic Loads in Comparison with Conventional Bridges

Bridges are divided into three categories of integral, semi-integral, and conventional (seat type) bridges, based on the connection of deck to abutment. The integral and semi-integral bridges have been widely used recently, while the interactions of soil with abutments and piles are important issue in designing them. However, limited studies have been carried out on the behaviors of integral and semi-integral bridges and, hence, a few specific and suitable designing indices for them can be found. In this study, a 3D finite element model for each type of bridges was developed and analyzed under seismic load. Due to the importance of soil-structure interaction, non-linear springs (links) were employed to simulate the effects of soil behind abutments and soil around piles on the structure. This study determined the effects of seismic loading on the abutment and its backfill soil in the conventional, integral and semi-integral bridge models, and also compared the equivalent exerted force from backfill soil to structure in these three types of bridge models.