Bridge bearings and expansion joint failures

28-05-2022

Elastomeric bearings and bearing pads are used in bridges and concrete buildings to support large vertical loads, lateral shear, and rotations of these structures by accommodating loads and movements due to thermal expansions, relaxations, creep, and rotations. The design criteria for these bearings are stringent engineering and are frequently not understood and followed. We here show a few examples of the failure of elastomeric bearings. These can be due to assessment errors of loads, shear and rotation, incompetent design capabilities, design errors and issues, and errors in manufacturing practices and maintenances, all of which lead to premature failure as well as earlier failure of bearings, including yield and rupture of internal reinforcement elastomeric layers, exposed steel shims, delamination of reinforcement, cracking or tearing of the rubber, fatigue, and instability, dislocation from bearing base, bearing walking.  The importance of the usage of  FMEA  to evaluate possible failures and prevent by correcting t proactively rather than reacting to adverse and costly events after failures are reported during defect liability and warranty period.  Prevention will always reduce the risk of expensive replacements including total replacement of newly designed and manufactured bearings. The careful design followed by prototyping, extensive load/shear/rotation testing to be done prior to final bearing type and size determination, then follow up manufacturing with proven experience in the process. Experimental results will be summarized, and the influences of different manufacturing techniques from rich experience are illustrated to provide a high-quality sustainable bridge bearings and expansion joints. Few pictures here are showing the outcome when bridge bearings are designed and manufactured and supplied by inexperienced vendors or even a few builders who try to cut corners to save pennies. Bridges and buildings have to be built with sustainability and social obligation to protect human life on and around these structures during and aftermath of a seismic reaction in the region. You need to work with an organization with decades of industry-proven experience, offering “CE” certifications which are hall mark of quality.