Owner: City of Akron
Contractor: The Great Lakes Construction Co.
Architect: MS Consultants, Inc.
Engineer: MS Consultants, Inc.
Concrete: Mack Concrete, Inc.
Slag Cement: Lehigh Hanson
This project consisted of construction of a 4.5 million gal. (17 million L) wastewater storage basin, three remote diversion structures, and associated 30 in. (760 mm) sewers and other utilities, as well as an operations building to support the new facility. The design included more than 70,000 yd3 (54,000 m3) of structural excavation and 10,000 yd3 (8000 m3) of cast-in-place concrete, 11 tipping buckets, two large screw pumps, and close coordination with Wheeling & Lake Erie Railway Company, the owner and operator of the active railroad tracks adjacent to the site.
Slag cement was used in all five mixture designs for mass concrete, structural walls, and accessorial concrete to meet shrinkage, permeability, and mass concrete temperature control requirements. Mixture designs ranged from 3000 to 8000 psi (21 to 55 MPa) with up to 35% cement replacement with slag cement.
The project was delivered as a construction manager at-risk (CMAR) project, allowing the City and all stakeholders including the CMAR and its contractors and suppliers to engage in the delivery of the project prior to design completion and facilitated open dialog throughout the project. The two large (9 ft [2.7 m] diameter, 52 ft [15.8 m] long) screw pumps are the keystone equipment on the project and are presently in successful operation for the city.
% Slag Cement Replacement
18 to 35% in five different mixture designs
% Portland Cement
82 to 65% cement content
% Other SCM (if applicable)
75 to 85% in 7 days
5500 to 9800 psi (38 to 68 MPa)