Experimental Study on the Dynamic Characteristics of a Vibration-Controlled Concrete Beam

摘要

Recent construction activities have given rise to civil petitions associated with vibration-induced damages or nuisances. Therefore, it is strongly needed to develop a remedial technique to mitigate unfavorable effects of construction activities. The objective of this research is to investigate dynamic material and structural characteristics of vibration-controlled concretes which have been mixed with various vibration-reducing materials, such as latex, rubber powder, plastic resin, polystyrofoam. Normal and high strength concrete specimens are also prepared. As a part of the research to study recycling obsolete aged tires and plastic materials, 32 concrete bars and 8 concrete beams have been made for investigating their dynamic properties. From the results of resonance tests on concrete bars, it can be concluded that a vibration-controlled concrete has relatively larger material damping ratio than a normal or high strength concrete. Styrofoam was determined to be the most effective vibration-reducing mixtures. Also, the flexural vibration tests on 8 concrete beams revealed that material damping ratio is much smaller than structural damping ratio for all the cases.