Sinkhole Surveying Nets Engineering Award

Ric Federico, EnSafe and Wendell Strode, Corvette Museum

On February 12, 2014, eight classic Chevrolet Corvettes were swallowed by a sinkhole that opened up beneath the Skydome of the National Corvette Museum in Bowling Green, Kentucky. A year later, the technology used to survey the sinkhole and surrounding areas nets local company EnSafe an award.

"Every year the American Council of Engineering Companies (ACEC) - Tennessee Chapter issues an award for engineering excellence," said Ric Federico, Senior Project Manager in the Bowling Green, Kentucky office of EnSafe, Inc. "For our work in mapping the cave without drilling into it from the surface, the EnSafe NCM microgravity project was entered into the Surveying and Mapping Technology category where it won the Grand Award."

EnSafe provided support in evaluating potential environmental and safety concerns in the Museum's Skydome during initial response activities, and subsequently designed and conducted a microgravity survey to evaluate the extent of the void and aid in identifying other potential karst features beneath the Skydome. EnSafe worked with Western Kentucky University (WKU) professors from the Department of Geography and Geology, who entered the void and prepared a cave map, which revealed excellent correlation between the microgravity data and the actual cave dimensions.

"We worked closely with WKU, Hayward Baker, and Scott, Murphy, Daniel early on and throughout the project to help the National Corvette Museum evaluate the problem and potential remedies, and we are pleased that our project and data were of value to the project team in developing and refining the micropile strategy," said Federico.

Geotechnical firm Hayward Baker is currently finalizing micropile installation and the Skydome construction is on track to be complete in July.

Museum Sinkhole Remediation Plan Outlined, Construction Starts November 10

Corvette Museum Skydome Sinkhole Viewing Ending Soon

National Corvette Museum officials met on Wednesday with construction personnel and engineers to review the plan, process and timeline for remediating the sinkhole and repairing the Skydome building.  Construction is slated to begin on Monday, November 10 and if everything goes according to schedule, the project will be completed by July, 2015.

The team reviewed the step-by-step process of filling the sinkhole beginning with the removal of boulders.  Late November through December the team will then install sheet piling to block the cave openings.  The hole will then be filled with about 4,000 tons of fist-sized #2 stone, taking place late December through mid-January, 2015. The remaining concrete slab flooring in the room will be removed in mid-January.  At that time, electrical, water and HVAC  repair work will occur through mid-February.

A quantity of 46 micropiles as well as grade beams will be installed mid-February through late March. The micropiles will be spaced 15-20 feet apart at an average depth of 141 feet based on the structural engineering design.  This design will ensure that if another collapse were to occur, the floor would remain intact.  Following this process will be the installation of additional stone as well as a new concrete slab floor (anticipated to take until late April to complete).  The final two months of construction will include the rebuilding of a new entrance with garage door and emergency exit doors, other repairs, repainting, installing new lighting fixtures, a thorough cleaning and other final touch ups.

Changes to the room will include a one-level natural color polished concrete floor without stairs and ramps like the current room has; the new garage door to allow for easy display car access as well as the ability to have an open-air entry for after-hours facility rentals; a redesigned drainage system; and 12 foot paved perimeter around the Skydome.  The cost of the project is just over $3.2 million.

While the Skydome web cams will be removed during the construction process, the Plexiglas viewing window will remain so that Museum guests can watch the on-going work.

The Museum team has received numerous ideas and suggestions on ways to tell the story of what happened on February 12, 2014 and provide interesting and entertaining aspects for visitors.  The Museum is currently exploring several options that include the opportunity to see down into the caves and 3D art.

The Museum plans to display the three restored Corvettes and five unrestored Corvettes in the Skydome once work has completed.

“We appreciate all of the support, feedback, ideas and prayers throughout this very interesting time in our history,” said Wendell Strode, Museum Executive Director.  “Sunday, November 9 will be the very last day to see the sinkhole up close and in person – so if you’ve been wanting to check it out for yourself you have just over three weeks to do so.”

Currently six of the eight “sinkhole Corvettes” are on display in the Skydome: the 1962 Tuxedo Black Corvette, 1984 PPG Pace Car, 1993 ZR-1 Spyder, 1993 40^th Anniversary Ruby Red Corvette, 2001 “Mallet Hammer” Z06 and 2009 “1.5 Millionth” Corvette.  After November 9^th the Museum will move as many of the cars as possible into other public viewing areas until the Skydome re-opens in July, 2015.

The National Corvette Museum is located at I-65 exit 28 in Bowling Green, Kentucky and is open seven days a week, from 8am until 5pm Central Time. Museum admission is $10 for adults, $5 for kids age 6 to 16, $8 for seniors or $25 family admission. Children age 5 and under are free, but are not allowed in the Skydome building. For more information on the Museum, visit www.corvettemuseum.org or download their free app on iTunes or Google Play, or call 800-538-3883.