REMAINING FATIGUE LIFE AND BEHAVIOUR OF DAMAGED RCBEAMS-REVIEW

R. Amaravel, G. Appa Rao

Abstract: Reinforced concrete bridges are often adopted in Railway construction of shorter spans to achieve simplicity in casting for required shape and size, easy to strengthen, riding comfort and speed of construction. These bridges consist of girders and deck slabs. When the speed and type of loading vary to transport ores, commodities and passengers, the bridges are subjected to higher stress range of fatigue than that designed. Assessment of remaining fatigue life of bridges either for retaining or strengthening or discarding purposes. Discarding the bridge can result in obstruction of traffic, reduction of revenue and loss of time, strategic needs and monumental structures. Experimental studies have been carried out for assessing the remaining fatigue cycles and flexural behavior of Damaged (cracked) Beams by fracture of tension reinforcement. The parameters of the study are; strength of concrete, percentage steel reinforcement and extent of damage in rebars. Load-deformation response and variation of strains across the depth at the level of center of beam, tension and compression reinforcements, extreme compressive strain in concrete, and crack propagation under fatigue load were analyzed. Review of Previous research on the fatigue life of bridges is presented. The test results are compared with the current ACI SP 75 design practice.

Keywords: Damage, RC beams, Compression reinforcement, tension reinforcement, Fatigue

DOI: https://doi.org/10.15623/ijret.2014.0328026