Blasting Paves Way for Centre Point High-Rise Development
The Centre Point commercial development in the heart of downtown Lexington is in full construction mode. It's a large scale project, recently redefined in scope, approaching a cost of 400 million dollars and including hotel-retail-office- and condominium uses.
In the development business, part of building up means tearing down. That process currently involves blasting to make way for an underground garage.
Construction crews have been on site between Main, Upper, Vine, and Limestone Streets for a few months now. Beyond the clanging of cranes and heavy equipment, on most weekdays other distinct sounds ring out. First the horn and then the blast sound out.
While Centre Point is thought of as a high-rise project, it will include underground parking. Webb Company's Dudley Webb says there's a fair amount of rock that has to be removed. "We're doing three levels of underground parking there, which involves about 31 feet of earth removal and stone removal," said Webb.
Webb says, in line with Kentucky's topography, there is a great deal of solid limestone to break through. So, traffic and activity around the work site stops briefly to carry out the blasting. A number of buildings, some designated as historic, surround the Centre Point block.
Webb says steps are being taken to help ensure no damage occurs to nearby structures. "They limit the size of the charges. You know, it took them a couple days to get that balanced out, but they're not exceeding the limits that the state places on us for the charges, so there's very little risk of that happening," added Webb.T
The contractor has photographed and surveyed buildings in the vicinity. Webb says those buildings will be re-assessed after blasting is over to check for any cracks or damage. Gas lines are also checked each day.
Raymond Hudson is the manager of the Kentucky Explosives and Blasting Branch. He says there are limits placed on blast-related vibrations and there's a definite line in the sand drawn. He says it's defined as two inches per second. "It's not two inches of movement. Don't confuse that. It's not saying they could shake the building two inches. It's just a peak particle velocity and it's expressed in terms of inches per second," explained Hudson.
Hudson says state inspectors are at the site on a regular basis and the contractor is using a seismograph to record ground vibrations.
Just across Limestone from the Centre Point site sits the law office building of Joe Mainous. The attorney says the building, constructed in 1979, was made to look much older. Still, he is keeping an eye on his property, "I've met with the third party engineers, prior to the blasts, we went over every inch of the building, documented any existing cracks, video taped it and used still photography." "I check the building twice a week, interior and exterior to make sure that I'm not seeing anything that is new," said Mainous.
Mainous says outside of a fair amount of dust flying on dry days, there's been minimal disruption from the blasting activities. Ironically, one of the biggest issues for his building so far came when the former buildings on the Centre Point block were being taken down. "In 2008, we had a catastrophic water problem that was due to a defective toilet seal and the engineer who examined the part said that it was a defective part that caused it and apparently what they think is that the vibrations from the demolition crew weakened that seal," explained Mainous.
Mainous says a claim was turned in to the insurance company and it was paid. Blasting at the Centre Point location is expected to continue for at least another two weeks. The entire commercial endeavor is projected to be completed by the end of 2015.