Vol 2 - Garney Construction

7. Use water-reducing and retarding admixture when anticipated hightemperatures, low humidity, or other adverse placement conditions canadversely affect fresh properties of concrete.8. Unless otherwise specified, desired fresh properties of concrete shall bedetermined by Contractor, and coordinated with concrete producer.Fresh properties of concrete shall remain stable to satisfaction ofContractor, for duration of placement and consolidation, and shallremain in conformance with requirements of Contract Documents.B. Potential Alkali-Aggregate Reactivity of Concrete: Do not use aggregatesknown to be susceptible to alkali-carbonate reaction (ACR).C. Proportions:1. Design mix to meet aesthetic, durability, and strength requirements.2. Where fly ash is included in mix, minimum fly ash content shall be aminimum of 15 percent of weight of total cementitious materials.D. Slump Range at Site:1. Unless otherwise permitted, target slump value is 4 inches at point ofdelivery, for concrete without high-range, water reducing admixture.2. Design mixes that include a high-range, water-reducing or a plasticizingadmixture shall have a minimum slump of 2 inches prior to addition ofadmixture. Unless otherwise permitted, slump shall be 8 inchesmaximum at point of delivery, for concrete with a high-range, waterreducingadmixture.3. Slump tolerance shall meet requirements of ACI 117.E. Combined Aggregate Gradation:1. Combined Gradation Limits: Limits shown are for coarse aggregates andfine aggregates mixed together (combined). Select one of the gradationsshown in the following table:Sieve SizesCombined Gradation Percentage Passing1-1/2"Max.1"Max.3/4"Max.2" 100 - -1-1/2" 95 - 100 100 -1" 65 - 85 90 - 100 1003/4" 55 - 75 70 - 90 92 - 100CAST-IN-PLACE CONCRETEPW/WBG/38205903 30 00 - 10 AUGUST 15, 2012©COPYRIGHT 2012 CH2M HILL