Experimental and numerical studies on the control of horizontal cracking at the ends of hollow-type pretensioned girders

Abstract

Recent bridge designs have created several efficient pretensioned prestressed concrete girder sections with high levels of prestress. Among them, hollow-type sections are of more consideration in Japan that exhibit good performance in practice. The transfer of large stresses from strands to concrete causes these sections to undergo horizontal cracking at the ends of the girders. To avoid such problem, this paper presents the implementation of various methods to the ends of two specimens prepared physically. Horizontal end cracks could not be fully eliminated by either of the methods in the selected type girder, but the method of enhancing end-zone reinforcement alongside strand-debonding could considerably decrease the principal stress that resulted in minimizing the cracks to a negligible level. To validate the experimental program, numerical models of the girder with identical parameters were simulated using the Finite Element Analysis software. Results obtained numerically well-matched the experimental ones to the extent of showing even the cracks pattern and vicinity.