Research contrasts resistivity test vs. w/c ratio to gauge permeability

Sources: Ready Mixed Concrete Research & Education Foundation, Alexandria, Va.; CP staff

A new RMC Research Foundation report based on work at the National Ready Mixed Concrete Association’s College Park, Md. laboratory addresses the lack of a consistent and cost-effective concrete permeability test method. “Reliability of Resistivity Tests of Concrete” authors evaluate mix design and specimen preparation factors that impact resistivity measurement; their conclusions can be incorporated in standards driving agency and engineer specifications in public and private concrete construction. 

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Optimizing Mixtures report advances paste-to-void, rejects minimum CM specs

Sources: National Ready Mixed Concrete Association, Silver Spring, Md.; CP staff

A new report on results of concrete mixtures testing at NRMCA’s College Park, Md., research laboratory underscores optimized cement paste volume and paste-to-void ratio as key factors behind fresh and hardened specimens’ improved performance characteristics.

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