For what is being termed as the first time in Karnataka, Ultra High-Performance Fiber Reinforced Concrete (UHPFRC) technology will be used to construct elevated corridors, as B-SMILE gears up to implement its ambitious 11 elevated corridors project aimed at decongesting Bengaluru.

B.S. Prahallad, Technical Director of B-SMILE, told The Hindu that the UHPFRC technology was planned to ensure faster completion and improved quality and aesthetics.

“The UHPFRC, a sophisticated concrete mix, offers greater durability and does not require reinforcement bars, which are traditionally used. This concrete mix has the strength to withstand pressures of up to 150 MPa, while normal concrete mixes have only one-third of this strength,” Mr. Prahallad explained. “It can also resist cracking under load much better than conventional concrete mixes,” he added.

With these qualities, the durability of the elevated corridors will increase significantly, according to Mr. Prahallad, who said it is two times higher than conventional structures.

Besides, the major thing about the UHPFRC is that the technology allows each span of the elevated corridors to be moulded up to 50 metres. “In the city, we have flyovers and metro structure spans that range from 20 to 25 metres and, in some cases, 30 metres. This will allow for a faster construction period and better aesthetics, as the spans will be longer,” said a B-SMILE source.

The UHPFRC technology has been used in two or three other States, but this will be the first time it is being used in Karnataka, according to sources.

The B-SMILE has set a project deadline of 18 months for all the elevated corridors. The special purpose vehicle (SPV) has floated tenders for constructing eight flyovers and a grade separator, with the total civil construction cost estimated at ₹3,530.04 crore, while the total project cost, including land acquisition and other contingencies, is estimated at ₹4,755 crore.

These structures are part of the eleven elevated corridors that received Cabinet approval last month. However, this project has faced considerable backlash from activists for seeing elevated corridors as the solution for congestion over improving public transport.

Accountability ensured

Typically, the Bengaluru civic body offers a liability and maintenance period of three to five years depending on the nature of the project. However, for this project, the SPV has set a maintenance period of 10 years, marking a transition to stricter quality control standards.

Earlier, the B-SMILE had planned a 10-year maintenance period for the Outer Ring Road redevelopment project in east Bengaluru. However, considering the complexity involved in that particular stretch, the B-SMILE resorted to a three-year maintenance period. Therefore, the elevated corridors project will be the first in Bengaluru to mandate a 10-year maintenance period.

Two flyovers to be tolled

While all the nine corridors for which tenders have been called will be free for commuters to use, the B-SMILE has planned to toll two other elevated corridors approved by the Karnataka Cabinet. The stretches planned to be tolled are the 28-km corridor connecting Yeshwantpur and Old Madras Road and the 18.50-km stretch connecting Marenahalli Main Road (Ragigudda Junction) and Kanakapura Main Road.

These stretches will be tolled because the construction will be undertaken under the Hybrid Annuity Model (HAM) with 40% Viability Gap Funding (VGF).