Stress analysis of three-span prestressed concrete bridge according to modified span length subjected to Thai truck load

Abstract

In the limited construction area, it is an alternative method that has the least impact on the existing bridge structures. The construction of the columns to support the bridge at an alternate position caused the modification in span lengths was chosen to study in this research. This method must be also achieved with the least impact of traffic. The threespan prestressed concrete bridge was simulated and analyzed by the finite element method. The models were subjected to the vehicles according to the standard loadings of Thai truck loads. The moving loads were applied to the bridge models which have the existing spans and varied spans caused by the construction of replaced columns. The variations in bridge lengths were ranged from 5% to 25% with an interval of 5% and caused the shortening of the first span and lengthening of the middle span. The bridge lengths were varied from 26.25 to 43.75 meters respectively. The stress analyses were carried out to determine the stresses induced in concrete, tendons, and rebars and then compared to their allowable strength. The conclusions were made for the span lengths which could affect the serviceability of the bridge.