Washington · answered by Verika · verified against sources
What slump is allowed for structural concrete on Washington highway projects?
For Washington highway projects, structural concrete slump limits are: 3.5" max for vibrated bridge decks/approach slabs/superstructures [1], 4.5" max for other vibrated concrete [1], 7" max for non-vibrated concrete [1], 9" max for shafts with Class 4000P (W/C ≤ 0.44 + water reducer) [1], and 5.5" max for curbs/gutters/sidewalks [1]. With high-range water reducers, add 2" to these limits [1]. For prestressed girders, slump ≤ 4" (normal), ≤ 7" (with HRWR), or ≤ 9" (HRWR + W/C ≤ 0.35) [2].
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