otorists would be able to enjoy a silky-smooth ride through flyovers proposed at Vyttila and Kundannoor since the structures would not have expansion joints which are the bane of most bridges.
The Vyttila overbridge maintained by NHAI is an apt example of how badly-designed and maintained expansion joints can provide a rickety ride to motorists.
“Expansion joints can be done away with for most bridges being built in Kerala, since extreme temperatures are rare in the State. While providing better ride quality, bridges sans expansion joints also reduce project cost by 15 to 20 per cent. They also make the structures more resistant to wear and tear,” said P. K. Aravindan, who served as Professor in Structural Engineering at IIT-Chennai and who resides in Kochi.
He played a key role in designing Kundannoor flyover which will be built sans expansion joints. The upcoming Edapally flyover too will not have these joints.
While they are mandatory every 45 metres as per norms, the A. L. Jacob overbridge near KSRTC bus stand and upcoming Pachalam overbridge have just two of them on either end of the railway span.
Pre-cast technology
The two flyovers will also adopt pre-cast technology which further reduces cost and construction time. Adopting this system will also lessen traffic chaos during construction phase since traffic regulation is needed only when girders are launched.
The 470-metre-long Vyttila flyover will also have a 40-metre-long central span – one of the biggest in the State, to enable smooth movement of vehicles beneath the structure, said P A Hashim, nodal officer for Kochi’s flyovers.
He said that a three-lane flyover proposed on each side of NH Bypass at the two junctions will be built first, followed by three-lane structure on the other side, to lessen traffic disruption.
Though the flyovers are expected to be commissioned in 18 months’ time, Finance Department has not granted its sanction to commence construction.
