Jamuna Bridge

We are Canadian bridge engineers visiting Bangladesh for a few days, on the invitation of Bangladesh University of Engineering and Technology (BUET) to give lectures on structural health monitoring and innovations in bridge engineering.
During our few days in Dhaka, many colleagues and friends have spoken to us about the 4.8km long Jamuna Multipurpose Bridge (JMB) being 'all cracked up', 'in great trouble', and having many cracks. After our lectures at BUET, there was also some discussion about the probable causes of cracks in the deck slab of the JMB.
In a recent issue of The Daily Star, the JMB is discussed twice: in an article 'Sick Bridge over the Jamuna' by Mohammad Nawazish, apparently a retired senior civil servant, and in a letter by Engr. Shaikh Wazir, presumably living in Tokyo.
The well-written article has served the purpose of raising public awareness about the safety of bridges. However, without the knowledge of the cause of cracks in the deck slab and their influence on the integrity of the bridge, i.e. scientific data, the conclusion that "the bridge is slowly and steadily approaching a very risky and painful end" is open to debate. Not all cracks are detrimental to the health of a bridge.
The writer of the letter does not seem to be an expert in bridge engineering. He concludes that the problems of the bridge are because it does not have expansion joints, or contraction joints as he prefers to call them, every 15 to 25m along its length. He recommends that the bridge with 100m spans should be cut up in 15 to 20m segments, a recipe for demolishing the bridge and not for saving it.
We believe diagnosing the cause of the cracks is possible. After the diagnosis of the cause of the cracks, the bridge can be monitored by a structural health monitoring and civionics systems, which monitors continually or periodically sensors installed on the bridge at strategic locations, and which ensures that the users of the bridge are not put to any unnecessary risk. If the diagnosis shows that the bridge has been weakened by the cracks, the bridge can be easily rehabilitated by using fibre reinforced polymers (FRPs), it should be noted that such rehabilitation is now routinely carried out in North America, Japan and several European and Far Eastern countries. Rehabilitation of concrete structures by FRPs can be learnt fairly quickly.
We have research teams in Canada that are scientifically monitoring more than fifty bridge structures, which have been installed with fibre optic sensors and state-of-the-art monitoring and civionics systems. These field projects could easily be studied in real time by visiting the website www.isiscanada.com. We recommend that the Canadian approach of monitoring bridges be pursued in lieu of opinions and speculations that are not based on scientific data.
Baidar Bakht, President, JMBT Structures Research Inc., Toronto, Canada, and Adjunct Professor of Civil Engineering, University of Toronto, Toronto, Canada
Aftab Mufti, Professor of Civil Engineering, and President, ISIS Canada, University of Manitoba, Winnipeg Canada