Installation of Elastomeric Bearing in Metro Rail Projects, Case Study and Solution

Abstract

Elastomeric bearings play a crucial role in bridge construction, providing vertical support to girders on piers while accommodating deformations caused by live loads and temperature changes. Steel-reinforced elastomeric bearing pads are commonly used due to their cost-effectiveness, combining stiffness from steel plates and flexibility from rubber. However, improper installation of elastomeric bearings can lead to various failures, disrupting traffic and incurring additional costs. This paper presents a case study of failure issues encountered in a Metro Rail project, highlighting the consequences of improper installation methodology and missed checkpoints. Formation of a true horizontal plane above the sub-structures and supper-structure (classification as per Indian Railways) is not difficult in the case of bridges constructed at zero gradient and in straight alignment, whereas special care must be taken to create a horizontal plane in bridges constructed in a gradient and on curve alignment. Additionally, the paper addresses the unique challenges faced in maintaining pedestrian level and ensuring complete contact of pre-cast over elastomeric bearings, providing guidelines, innovative solution, and methodology for their installation.