An osmotic method for determining rock and aggregate suction characteristics with applications to frost heave studies

Summary A recently developed laboratory method in which suction is applied by osmosis has been used to determine the suction/moisture content relationships (suction characteristics) of limestone rock and compacted aggregate specimens. The method, which is described in detail, gave results which were comparable with those from the suction plate and pressure membrane apparatus. It is, however, much superior to these other methods and for the first time permits aggregate suction characteristics to be determined easily. The suction characteristics have also been used to rank the frost susceptibilities of four limestones. Pore size distributions inferred from the results are consistent with microscope studies.