Investigation of Flexural Behavior of Self-Compacting Concrete Beams
|關鍵字:||自充填混凝土;撓曲強度;韌性;裂縫控制;self-compacted concrete;maximum moment strength;ductility;crack control|
An experimental program was conducted to investigate the maximum moment strength and ductility of the self-compacted concrete (SCC) beams and compared with those of ordinary property cement (OPC) beams. Twenty-seven SCC beams and five OPC beams were fabricated and tested with vertical monotonic load to investigate the flexure behavior of reinforced concrete beams. The parameters considered were type and strength of concrete, amount of longitudinal steel, space of stirrup, yield strength of stirrup and shear span-to-depth. Observation during the tests indicated that the pattern of crack initiation and propagation for SCC and OPC beams were similar to each other. The values of experimentally obtained maximum moment strength of SCC and OPC beams were higher than the values calculated by ACI code. The SCC beams and OPC beams had similar maximum moment strength. The results demonstrated the suitability of ACI equations for SCC beams. Experimental results showed that an increase of tension reinforcements would increase the maximum moment strength but decrease the ductility of the beams. The increase of the compression reinforcements would increase the maximum moment strength slightly and more on the ductility of the beams. Decreasing the space of stirrup would increase the ductility of the beams. The ductility of the beam with a/d = 3.443 was better than the beam with a/d = 4.426. With all the other parameters same, SCC beams performed somewhat better than OPC beams on the ductility. Based on the observation during the tests, we found that the crack width of the beams with stirrups of higher yield strength ( ) still satisfied the crack width limitation of ACI code in accordance with the Gergely-Lutz equation. SCC beams had better crack control than OPC beams. Decreasing the space of stirrup would make more closely spaced flexure cracks and thus better crack control.