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Through a lot of team effort, Central Concrete Supply Co., San Jose, Calif., was able to place 13,614 cubic yards of concrete continuously for the foundation mat for an 18-story office building in downtown San Jose. 65 ready mix trucks, from three plants, all arriving at the same check-in point, were used for the pour. The flow of trucks and concrete to the five pumps working the site, was regulated by workers with two-way radios. An average delivery rate of 630 cubic yards per hour was maintained up to the last few hours of the pour. A single aggregate source was used to ensure consistent quality and moisture content. The 5 « sack mix contained 25% fly ash and attained an average strength of 4000 psi in 28 days and 5500 psi in 56 days.