With all of the damaged vehicles removed from the sinkhole beneath the Skydome at the National Corvette Museum, options are being considered about the repairs needed to restore the facility and those vehicles. One option is to preserve a portion of the sinkhole for future museum visitors to see and to learn not only about the collapse, but about the ground beneath not just the museum but the entire area.
The museum is located at Bowling Green, Ky., not far from Mammoth Cave National Park, and in an area known for extensive underground caverns. Some 200 such caverns are documented beneath Warren County, including some within the city limits of Bowling Green, which also is the location of the Corvette assembly plant.
Bowling Green also is home to Western Kentucky University, which has a geoscience department staffed by professors expert in these “karst” geologic environments.
Last week, two of those professors, Leslie North and Jason Polk, met with museum officials to discuss findings from drillings, microgravity readings and from personal exploration in the sinkhole.
Polk said the void beneath the Skydome extends in two directions — from the Skydome toward the museum parking lot and from the Skydome toward a nearby pond.
“You don’t typically have sinkholes without caves or voids of some type below them, so this finding was not surprising,” he is quoted in a museum news release. He also told museum officials that in some cases sinkholes in the area have been found to be miles in width.
He said mineral deposits removed for study indicate dry conditions in the northern extension of the cave, meaning that portion of the hole likely is thousands of years old and probably hasn’t had water flowing in it for a very long time.
The museum reported that prior to its construction, a geo-technical test was completed in accordance with normal building standards. No problems were discovered at that time.
“Normally, if there is enough rock, it doesn’t matter what is below it,” said Danny Daniel of Scott, Murphy & Daniel Construction, which did not build the original museum but which handled excavation and removal of the eight cars that fell into the sinkhole.
Daniel also said rebar was not required in the construction of the Skydome’s original concrete flooring
“It’s no different than the floor of your garage at home,” he was quoted. “Rebar was not needed to support the weight of the cars in the Skydome.”
The preliminary conclusion is that the sinkhole most likely was caused by the collapse of a portion of the cave roof, which could have been caused by the extra weight from clay soils above the roof being saturated by recent heavy rains.
More information is expected Saturday, April 26, when WKU professors Pole and North make another presentation on the sinkhole collapse in the museum’s conference center.
Meanwhile, the museum team and construction experts are exploring ways to rebuild the Skydome floor. One plan includes drilling, installing what are known as micro piles, and then adding support beams beneath the floor.
The process has not moved along far enough to know if keeping a portion of the hole is feasible or not.” — Wendell Strode
The process has not moved along far enough to know if keeping a portion of the hole is feasible or not.”
— Wendell Strode
“We will continue to explore these ideas… the process has not moved along far enough to know if keeping a portion of the hole is feasible or not,” said Wendell Strode, the museum’s executive director.
Strode reported that interest in the museum and the sinkhole and rescued cars “has been more than expected, and our attendance for March was up 56 percent over March of last year.
“Our special display focusing on this event is now open in our Exhibit Hall. Current plans are to keep the cars on display as they are so that guests through the summer and especially the thousands attending our 20th Anniversary Celebration will have a chance to see the cars and witness the sinkhole for themselves,” he said.
In addition to the eight damaged cars on display, a huge boulder that had been atop one of those cars has become part of the landscape decor just outside the museum.
As reconstruction plans are being made, representatives from General Motors are scheduled to meet with museum staffers in May and to inspect each of the eight cars and determine which ones are appropriate to be restored. Cars not restored will be kept on permanent display as part of story of the February 12 sinkhole collapse, the museum said.