EXPERIMENTAL STUDY ON PERFORMANCE OF RC BEAMS WITHOUT STIRRUPS UNDER VARIOUS LOADING RATES WITH FALLING WEIGHT HAMMER
In order to deeply investigate the shear-resistant behavior of reinforced concrete (RC) beams under various loading rates,experimental study on six identical simply supported RC beams without stirrups with falling weight impact hammer was carried out. The cross section is 150 mm width and 310 mm depth and three longitudinal reinforcements with diameter of 16 mm located with offset of 25 mm from the bottom surface of the beam. The impact load is applied at the middle span of the beam and the identical shear span to depth ratio is 3. 47. Firstly,static test one of the beams was carried out and the shear failure pattern was observed. Then,impact tests on other with impact velocity from 3. 5 m/s to 9.0 m/s and falling weight of 333 kg and 200 kg were carried out. The failure patterns of specimens under different loading rates but identical impact energy were also investigated. Crack developing process of specimens was photographed by high speed video camera and crack patterns of all specimens at failure state were sketched and compared with each other. Specimens under lower velocity and lighter mass impact showed different failure crack pattern from that under high rate loading and heavier mass impact cases. But all beams were in failure with severe diagonal crack in the middle span. Time histories of impact force were recorded and analyzed. Resistance strain gauges were employed to measure the strain distribution in concrete and rebar along the beam and across the cross section. From the strain data,distribution characteristic of flexural moment along the beam span was inferred in the process of impact. Results showed inertia had obvious effect on the impact behavior of beam.
Xiang Zeng Bin Xu
College of Civil Engineering,Hunan University,Yuelu Mountain,Changsha,Hunan 410082,P.R.China College of Civil Engineering,Hunan University,Yuelu Mountain,Changsha,Hunan 410082,P.R.China Ministr
国际会议
厦门
英文
822-827
2011-10-28（万方平台首次上网日期，不代表论文的发表时间）