Title: Concrete Q&A: Slump Requirements per ACI 301 and Roughening of Existing Concrete to 1/4 in. Amplitude per ACI 318
Publication: Concrete International
Appears on pages(s): 72
Q. ACI 301-101 calls for the slump to be proportioned to 2 to 4 in. (50 to 100 mm) prior to a high-range water-reducing admixture (HRWRA) being added and calls for a maximum slump of 8 in. (200 mm) at the point of delivery after the addition of the admixture. How is this handled when a HRWRA is added at the batch plant prior to arriving at the site?
Q. When does ACI 318-141 require a 1/4 in. (6.4 mm) amplitude on existing concrete before new concrete is placed against it?