MEASUREMENT SYSTEM FOR FLUCTUATION OF CONCRETE FLOW IN TAPERED PIPE WITH HELP OF VISUALIZATION TECHNIQUE

In order to evaluate the deformability of fresh concrete flowing in pipes, a new system was developed in this paper to obtain the information about movements of mortar and coarse aggregates with help of the visualization technique. For visualizing the concrete flow, concrete was replaced by the model concrete made of transparent mortar and specially designed coarse aggregates, and the pipe was made by the transparent plastic material. Movements of mortar and coarse aggregates were recorded by the Video System, and were traced and analyzed by the Graphic Analyzer. It was observed that there existed the fluctuation in concrete flow at the tapered portion of pipe. Since the fluctuation should be concerned with the deformability of fresh concrete, the index for evaluating the degree of fluctuation was proposed.