Recommendation of RILEM TC 258-AAA: RILEM AAR-13: application of alkali-wrapping for concrete prism testing to assess the expansion potential of alkali-silica reaction

Abstract

The RILEM AAR-13 test procedure is not a test method by itself; rather it is a procedure applying alkali wrapping to concrete prisms during test exposure to assess the expansion potential of alkali-silica reaction. When combined with procedures of other test methods, for example AAR-10 or AAR-11, it becomes a full test procedure. The wrapping procedure described was originally proposed by a technical committee of the Japan Concrete Institute “Technical Committee on Performance Based Design and Maintenance Scenario with Controlling ASR Deterioration”. The procedure includes a detailed description of the materials to be used for wrapping, procedures for calculation of alkalinity of the solution that aims to simulate the pore solution of the concrete prism depending on the alkali content of the concrete, and finally specific procedures for storage and measurements of the prisms. The procedure of calculating the alkalinity of the solution to be applied for the wrapping is assumed to be conservative because no subtraction is made for assumed alkali binding by the hydrates or alkali absorption by the aggregates. The alkali content is estimated by adding the alkali contribution from all concrete constituents (except the aggregates) including the supplementary cementitious materials (SCMs).