Jet grouting effect will determine Ungka Flyover’s Phase 2 repairs

By Rjay Zuriaga Castor

The second phase of rectification for the “sinking” Ungka flyover in Pavia, Iloilo, will hinge on the results of the ongoing monitoring studies of the structure’s P680-million initial repairs, according to the Department of Public Works and Highways-Western Visayas (DPWH-6).

“We are looking at phase 2 where we can have additional bored piles in piers 4, 5, and 6. However, we are monitoring the result of our jet grouting for every pier of Ungka,” DPWH-6 director Sanny Boy Oropel told Daily Guardian.

The first phase, a P96-million project handled by Monolithic Construction & Concrete Products, Inc., involves jet grouting of the flyover’s 13 piers to stabilize the main girders.

Oropel disclosed that daily seismic tests are being conducted to gauge soil stability improvements due to the jet grouting process.

“If our seismic result will confirm an effect from our jet grouting, perhaps we will have an alternative design for us to fast-track our rectification,” he added.

Jet grouting, which includes shoring to prevent soil retained in the excavation from collapsing, strengthens the soil base by injecting a cement mixture.

Oropel also noted the possibility of design changes that may or may not necessitate another closure during the flyover’s second phase of rectification.

“As of now, we are not saying that there will be a closure again in Ungka, but definitely if we start and we will follow the original design, we will surely have a closure since we have to demolish the spans above. Everything is very fluid as far as the design methodology [is concerned],” he said.

Originally, phase 2 of the repairs will focus on rectifying the settlement or displacement at piers 4, 5, and 6, which would require demolishing the spans that the three piers support.

International Builders Corporation (IBC), the original contractor for the flyover, will undertake the removal.

The second phase of repairs will commence this week, starting with the bidding of the P200-million contract.

The bidding process for phase 2 repairs is open to all qualified contractors, including IBC, as confirmed by Oropel.