BS 812-121:1989

Committees responsible
Foreword
1 Scope
2 Definitions
3 Principle
4 Sampling
5 Apparatus
6 Reagents
7 Preparation of test portions and specimens
8 Procedure
9 Calculation and expression of test results
10 Precision
11 Test report
Appendix A - Recommended procedure for determining
             the magnesium sulphate soundness value
             for other size fractions of aggregate
Appendix B - Details of the evaluation of precision data
Publications referred to

Aggregates passing a 14.0 mm test sieve are subjected to cycles of immersion in magnesium sulphate solution followed by oven-drying. A method for other sizes of aggregates is also described.

This Part of BS 812 describes the method for determining the soundness of aggregates by subjecting the aggregate to cycles of immersion in a saturated solution of magnesium sulphate followed by oven-drying. The method is applicable to aggregate passing a 14.0 mm test sieve but is retained on a 10.0 mm test sieve.

NOTE 1 The majority of aggregates can be tested for soundness using this method. Precision has been established for the rock types listed in Table 1. The test may not be suitable for all rock types and reservations have been expressed elsewhere in respect of some carbonate aggregates and some aggregates having a high proportion of magnesium bearing minerals or of cryptocrystalline quartz.

For other size fractions, a recommended method is described in appendix A.

NOTE 2 The titles of the publications referred to in this standard are listed on the inside back cover.