Abstract
This study demonstrates the potential of posttensioning truss bridges. Posttensioning deficient truss bridges using different posttensioning tendon layouts can be a cost-effective method to strengthen them and to increase the redundancy levels as well as the reliability of the truss structures to meet current and future loading and traffic requirements. Methods for the assessment of the reliability and redundancy of posttensioned trusses are suggested. The effect of posttensioning on the structural strength of the individual components and the overall system of trusses is investigated. Posttensioning enlarges the elastic range, increases the fatigue resistance, redundancy, and relibility, and reduces deflection and member stresses. Thus, the remaining life of a truss bridge can be extended relatively inexpensively.