By Haresh Jhala
Ahmedabad, Nov 5 (SocialNews.XYZ) The recent Morbi bridge tragedy that claimed over 140 lives points to gross negligence of Morbi Nagar palika as it handed over the renovation contract to an agency without due diligence, says a Bridge Structural Engineer expert.
Speaking on condition of anonymity, the expert told IANS, "The nagar palika was duty-bound to carry out structural analysis before giving out the renovation contract. Also, it should have taken into consideration the wind & live load, steel structure, load test, and stability test. Based on these data, it should have assessed and prepared a structural design meeting present and the future requirement and then placed an order for the renovation, which meets the Bureau of Indian Standards for Building structures.
The British-era bridge was built 143 years ago based on wind and live load of that time and earthquake resistance.
Even the water salinity issue should have been taken into account. Over a period of time, the bridge would have undergone several changes, hence even the minutest of things should have been considered as every factor matters in bridge design and construction.
Citing the SA's Tacoma narrow bridge collapse in 1940, the expert said that was the first suspension bridge tragedy. It failed to withstand the 40 miles per hour wind velocity. Even when the bridge was under construction, in a little breeze, ripples were running along the bridge.
In another case, he said a suspension bridge during World War II, managed to even withstand the vibration created by the marching of Army over it as they refrained from putting undue pressure on it and crossed it in relaxed mode.
Coming back to the Morbi bridge, the expert said while redesigning the suspension bridge, the nagar palika seems to have ignored the Indian standards (IS) for earthquake (seismic load), IS 875 for wind loads on buildings, IS 800 general code for steel structure. Also, it should have carried out live and dead load, erection stresses.
When asked to issue certificates for bridges constructed by the government or semi government agencies, he personally carries out load and stability tests, only after verifying that standards are met, does he issue certificates, the expert stated.
Was this followed in the Morbi bridge case? he wondered.