ASTM C1857/C1857M-19 PDF Download

The ASTM C1857/C1857M-19 standard is a test method used to evaluate the adhesion (pull-off) strength of concrete repair and overlay mortar. It is designed for laboratory use and aims to determine the bond strength between the repair or overlay material and a specific concrete substrate.

The test measures the strength of the bond by applying a tensile force to the repair or overlay material. The result obtained is either the bond strength to the concrete panel or the tensile strength of either the overlay or concrete panel, depending on which is weaker. The test evaluates the failure mechanism requiring the least stress, and the failure mode is reported for each individual test result. Test results are only averaged if the same failure mode occurs.

This test method can also be used to evaluate the performance of bonding agents. However, it should be noted that the results obtained are only applicable to the standard substrate and are not intended to determine bond strength for field applications.

The standard provides guidelines for conducting the test and standardizing conditions to ensure comparability of results between laboratories. It also includes conversion factors for units of measurement that differ from those used in the test method. The explanatory notes and footnotes in the standard should be considered for further understanding but are not requirements of the test method.