STP992: Inadequacy of Property Specifications in ASTM C 270

    Robinson, GC
    Professor of Ceramic Engineering, Clemson University, Clemson, SC

    Brown, RH
    Professor and Head of Civil Engineering, Clemson University, Clemson, SC

    Pages: 11    Published: Jan 1988


    Bond strength and water leakage were determined for Types M, S, and N mortars joined to six different brick types. The air content, water retention, and flow rate were varied for each mortar-brick combination. It was found that air content, water retention, and compressive strength were inadequate indices of bond strength and water leakage. Yet these are the only properties specified in ASTM Specification for Mortar for Unit Masonry (C 270-84). A plea is made to add a bond strength requirement to present property requirements. The initial rate of absorption (IRA) of brick was found to be significant in predicting water leakage. Low IRA brick provided the highest probability of zero leakage.


    masonry, mortar, bond strength, water retention, air content, compressive strength, water leakage

    Paper ID: STP27257S

    Committee/Subcommittee: C15.04

    DOI: 10.1520/STP27257S

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