Owner: Columbus Zoo and Aquarium
Contractor: George J. Igel & Co., Inc.
Architect: PJA Architects + Landscape Architects
Engineer: Jezerinac Geers & Associates
Concrete: Buckeye Ready-Mix, LLC
Slag Cement: St. Marys Cement
This project included three saltwater pools that hold 375,000 gal. (1,420,000 L) of saltwater along with multiple buildings for housing animals and equipment spanning a 4.1 acre (1.7 ha) area. The pools have acrylic glass for viewing underwater and also a one-of-a-kind tunnel that is 360-degrees acrylic for complete viewing of the animals swimming around the tunnel. The project had to maintain a natural environment that resembles the Pacific Northwest rocky coast while also being watertight and durable due to the saltwater. The buildings house animals from all around the world as part of a public interactive experience. The area will allow interaction with the animals, teaching of animal environment, and shows featuring the sea lions.
Slag cement was used for durability enhancement and potential sulfate and alkali silica reaction (ASR) mitigation. A polycarboxylate plasticizer was required for cement dispersion, strength enhancement, and desired placement slump. As a result of the polycarboxylate used and the low water-cementitious materials ratio (w/cm), concrete design strengths were achieved at 7 days.
The majority of the concrete furnished was a 5000 psi (35 MPa) design, which performed extraordinarily well. Approximately 1700 yd3 (1300 m3) of ready mixed concrete was placed, and there was not one 28-day break that failed to meet design strength requirements. Many times, the design strength was exceeded at the 7-day break. The strength of the ready mixed concrete provided was very consistent, which will lead to extended durability of these structures.
Xypex Admixture was used in lieu of waterproofing in order to create a watertight structure in the pools and building slabs. The interior of the buildings also houses holding pools for the animals that had to be watertight. The center pool has a 360-degree acrylic tunnel so that the sea lions can be seen as they swim all around the zoo visitors. The three pools hold 375,000 gal. of saltwater that has to be kept watertight in order to keep the saltwater mixture at optimum level
% Slag Cement Replacement
% Portland Cement
% Other SCM (if applicable)
2% Xypex C500
#57 & #8 Limestone Blend
0.40 (658 lb minimum cementitious materials)