Seismic retrofitting of an historical bridge in Yangon, Myanmar

Bridges are unarguably one key component of the transportation infrastructures.

In early 2017 BIT was invited through the Malaysian Rubber Export Promotional Council (MREPC) and the Malaysian Service Providers Confederation (MSPC) to initiate a seismic retrofitting project in Yangon, Myanmar. Activities carried out by BIT are within the framework of a government-to-government project.

A classic steel bridge, the Bayintnaung Bridge in Yangon, designed by a renowned European designer few decades ago, was identified by the Ministry of Construction (MOC) of Myanmar to be retrofitted. The bridge play a strategic role for the transportation system of Yangoon.

The original bridge was supported by sliding bearings with shear keys in selected piers only. Due to the soil movements on the abutment, some of the existing supports beneath the deck displaced out of their initial position.

In December 2017 BIT has submitted its final report on the proposed seismic retrofit solution that makes use of High Damping Rubber Bearings (HDRBs) made of natural rubber as seismic isolators to minimize the impact of earthquakes on the steel-trussed bridge. The report also contains design of the proposed HDRB as well as recommendations and procedures for replacement of the existing bearing. Doshin Rubber Products (M) sponsored the seismic isolators.

The final report is now with the Ministry of Construction of Myanmar and the actual field work for seismic retrofitting is expected to begin in the second half of 2018, subject to the decision of the local authority of the country.

BIT, thanks to its experience in structural monitoring, will carry out a full dynamic characterisation of the bridge in its actual condition and after the retrofit and will install a wireless sensor network for monitoring.