ACI 304.2RS-96

This report describes pumps for transporting and placing concrete. Rigid and flexible pipelines are discussed and couplings and other accessories described. Recommendations for proportioning pumpable concrete suggest optimum gradation of aggregates; outline water, cement, and admixture requirements; and emphasize the need for evaluation of trial mixes for pumpability. The importance of saturating lightweight aggregates is stressed. Suggestions are given for layout of lines; for maintaining uniform delivery rate, as well as uniform quality of concrete at the end of the line; and for cleaning out pipelines. This report does not cover shotcreting or pumping of nonstructural insulating or cellular concrete.