San Diego, CA
Award: Lower Carbon Concrete
Owner: San Diego State University
Engineer: Magnusson Klemencic Associates
Concrete: Pacific Southwest Construction, Inc.
Slag Cement: CEMEX
In this project slag cement was used in all usage areas. The mat slab and footings have 60% slag cement and it reduced the heat of hydration in the mass concrete to meet the specification. The slab on grade and decks had 40% slag cement. The use of slag cement as a SCM helped the contractor overcome issues related to mass concrete in the large foundations required for the stadium project. Slag cement also improved final strength and appearance of this project.
The high percentage of SCM used was made possible using slag cement. Other SCMs were limited by the project specifications to 30%, but slag cement allowed the increase of SCM usage up to 60% cement substitution. Due to the use of slag cement, Cemex could provide its low carbon concrete, Vertua®, to the project. We could reduce CO2 emissions in the project by 30% compared to 100% straight cement OPC mixes. Total CO2 reduced by this comparison is equal to 4,000 metric tons.
The Stadium is built with approximately 38,000 cubic yards of ready-mix concrete and required large mat pours which took place on a critical schedule. The reliable availability of slag cement added to the certainty of material supply which helped in accelerating the project schedule, allowing the contractor to meet and exceed the project schedule. The Stadium serves as the anchor of the 80-acre SDSU Mission Valley redevelopment on the old Qualcomm Stadium site. More information and pictures can be found at https://aztecstadium.com/.
“Aztec Stadium is designed to meet the needs of the entire San Diego community. This year-round entertainment destination will serve as a hub of community engagement and Aztec pride. Designed to achieve LEED Gold certification, the 35,000-capacity stadium, with flexibility to expand, will serve as the home for Aztec Football. San Diego State University will work with partners in the tourism industry to secure opportunities to host NCAA championships, international soccer, concerts, festivals, high school sports, and other entertainment events.” Above quoted from https://missionvalley.sdsu.edu/explore/stadium
% Slag Cement Replacement
% Portland Cement
% Portland Limestone Cement
% Other SCM (if applicable)
Variable from .40 to .50