A structural engineer who is tasked by Mayor Tomas Osmeña to examine the foundation of the City Hall’s executive building yesterday vouched that the building’s foundation is stable and safe for occupancy, even if more technical study on the matter is still to be conducted.
Engineer Ricky Dakay, accompanied by city information and protocol officer Nagiel Bañacia, yesterday morning visited the basement of the eight-storey building where some cracks on the flooring were found by some members of the Civil Security Unit a few days ago.
Dakay measured the cracks and found that most of them measured only about two millimeters in width and between two- and three-mm in depth.
“Initially, Ricky (Dakay) told me that there is no cause for alarm. The cracks do not affect the integrity of the building and its foundation. The cracks are just too shallow; these did not indicate significant structural distress or a lack of durability,” Bañacia quoted Dakay to the media.
The structural engineer also ruled out possibilities that the cracks were caused by plastic shrinkage cracking, settlement cracking, or drying shrinkage caused perhaps by the lengthy use of the building. These are caused during construction period, Dakay said.
The design and the building plan will still be subjected for further technical study, said Dakay, adding that some personnel will be sent to do some non-destructive testing on the basement.
They will be “tapping the surface with a hammer or using a chain drag, which are the sample techniques to identify the planar crackings near the surface,” he said.
Bañacia said that Dakay’s evaluation so far showed that it is unlikely for the city to restore or increase the strength of the basement.
The building was constructed by WT Construction some eight years ago during the administration of then mayor Alvin Garcia. Dakay Construction and Development Corp. was among those that participated in the bidding for its construction.
Concerns over the stability of the building were raised days ago after the discovery of some cracks on the basement floor. CSU personnel also noted white crystalline substances, resembling salt, on the cracks that led to the suspicion that seawater might have intruded into building’s foundation. It was recalled that the site where the building was constructed was a reclaimed area off the city shoreline.
Osmeña, upon learning of the discovery, however allayed fears of the employees by telling them that there is no cause for alarm because city engineers have notified him that the cracks are small and not of high-risk condition.
The mayor still hired the services of Dakay, who he considered the best structural engineer in the city, to check and investigate the cracks for a confirmation of the initial findings of stability.
Dakay also gathered some of the white substances found in the cracks, and Bañacia said that the specimen will be sent to the University of San Carlos laboratory to determine what these are.
It could be salt or sea water but it could also be chemical reactions from engine oil, or paints from the metals of ballot boxes that have been stored in a portion of the basement. “But we don’t have scientific answer on this until the laboratory test,” Bañacia said.
There was no conclusive result yet on the matter of chemical reactions, which might have resulted from the cracking of the concrete flooring, he said.
“These reactions may be due to the aggregates used in making cement, or to some materials that came in contact with cement after the latter hardened. It’s like the engine oil, metal rusts, etc. You know, there are many materials that are being stacked at the baseline like the hundreds of ballot boxes, video karera and worst even garbage,” Bañacia explained in an email.
Dakay had suggested to the city to stop the washing of cars at the basement to avoid an accumulation of stagnant water. He also recommended to the city to provide water tightness, improve the appearance and durability of the concrete surface, and prevent the access of corrosive materials to the concrete reinforcements.
This prompted Bañacia to request for the immediate transfer of ballot boxes from the storage area at the basement.
“I hope the city administrator and the city treasurer would give utmost importance to this. I have been calling for the transfer of the ballot boxes since last year, but it seems nobody is working on it,” Bañacia said. –RAE