Experimental study on optimization of water reducer in pumping concrete

摘要

The different water reducers have different suitability and different influence of performance with concrete mixture. Combined with the engineering practice, 3 kinds of naphthalene-based water reducer (NSR) and 4 kinds of polycarboxylate-based water reducer (PC) were selected as the objects. The saturation dosage of water reducers was determined by single factor test. Using the concrete standard mixture in the saturated dosage of the water reducer, the pumping concrete slump loss, gas loss, bleeding rate, setting time and separation properties about the 7 kinds of water reducers under the state of the coarse aggregate saturated surface dried and air dried were tested in order to select 4 of the adaptability of water reducer. By testing 4 kinds of water reducers, it's shown that the performance of concrete mixed with water reducer is optimal after 60 minutes.