SELECTION OF TEST ME THOD TO QUANTIFY WOR KABILITY OF CEMENT PASTE AND MORTAR FOR VERY LOW WORKABLE TO HIGH WORKABLE MIX

Cement paste and mortar fresh properties governs concrete characteristics. Selection of test method to measure workability is based on mix characteristic . Very low workability mix test method differs from the high workable mix. First attempt was made by author s to develop correlation between two tests and cover entire range of workability i.e. from very low to high workable mix. Mini flow table testand marsh cone test were selected for cement paste and mortar. Marsh cone test is applicable beyond W/C ratio 0.50 for cement paste. Mini flow table test shows same flow diameter above W/C ratio 0.50 for cement paste. It is possible to evaluate flow behaviour of cement paste up to W/C ratio 0.62 by modifying cement paste cone volume . M arsh cone test was applicable beyondW/C ratio 0.72 for cement mortar having cement to fine aggregate proportion 1:1. Mini flow table test has diameter 250mm which is useful to measure low to medium workable mix of mortar. High workable cement mortar mixture spread is more than 250mm therefore it is necessary to do dimension change in mini flow table test. Modified mini flow table test having diameter of 450mm was applicable for entire range i.e. very low to high workable mix