Download or read book Key Way Joint Strength of Precast Box-Beam Bridges written by Mohamed Habouh and published by . This book was released on 2015 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: Satisfactory performance of non-composite adjacent box-beam bridges depends on the effectiveness of the key way, waterproofing membrane and tie rods, and the related construction practices. Development of cracks at the longitudinal joints of such bridges is often a recurring problem that causes water leakage at the joints and corrosion of the embedded prestressing strands. The primary objective of this study was to identify the sources, causes and effects of inadequate joint performance in adjacent box-beam bridges, and to develop prevention measures. The structural performance of key way joints with the existing and new grout materials were evaluated and correlated with field measurements under traffic loading. Observation of construction practices and an investigation of a bridge that was in service for 32 years at the time of its demolition were also included. This study revealed that shear transfer strength of key way joints under symmetric loading can be increased compared to the joints that use the current ODOT-approved grouts and key way details through proper selection of grout material, adjustment to the key way geometry, and joint surface preparation. In beam configurations, this increase can be by a factor of up to 7.3 prior to the occurrence of first crack. Key way joints with a combination of the currently specified ODOT geometry and ODOT-approved grouts are incapable of carrying any shear loads in conjunction with out-of-plane moments. However, with suitable modifications, it is possible to increase the shear strength of these joints under eccentric loading. From the limited site inspections done in this project, the practices followed at construction sites seem to be seriously flawed and may be largely contributing to water leakage problems in box-beam bridges. New key way geometries and the grouts that were developed and tested in this project are suitable for implementation.