Slag cement supplied by Skyway Cement contributed to the successful construction of a concrete wastewater storage facility in Louisville, Ky. which will reduce water pollution in the Ohio River.
The Louisville Metropolitan Sewer Department developed the Shawnee Park Basin to collect rain water runoff and help control flooding. It retains mixed sewage/rainwater during heavy rain events to keep untreated sewage from flowing into the Ohio River. The 40 ft deep basin with an area of 487 x 254, and a capacity of 20 million gallons is completely underground, with one of Louisville’s premier parks constructed on top. The basin required 30,000 cu.yds. of concrete. The reinforced concrete roof is 36” thick and supports 12 feet of soil making up the park area. Community input was paramount in the design of the basin and park, as it enhances both water quality and community life. The basin is virtually invisible to the public. The project was completed in 2017.
Skyway slag cement used in the underground basin structure was critical in achieving the project objectives:
Keeping the concrete temperature low to prevent thermal cracks, which could cause leaking or deterioration of reinforcing steel due to ingress of effluent. Specification called for 150oF maximum temperature. Internal temperatures ranged 105 to 115oF.
Enabling the concrete to be self-consolidating (22” spread), to facilitate faster, more economical placement and finishing, without voids around the dense reinforcing steel and formwork. A 50% cement / slag cement mix design was use.
Achieving low-permeability and resistance to sulfates so the concrete can resist deleterious substances in the effluent.
The slag cement content enabled the project to consistently exceed required strength levels (specification 5,000 psi @ 28 days), reaching 28-day strengths of 7,000- 9,000 psi.
Louisville Metropolitain Sewer District
FA Wilhem Construction Company
Allied Ready Mix