2011 Volume 67 Issue 3 Pages 361-373
Since most of the pre-cast reinforced concrete (RC) products have thin thickness, failure mechanisms of thin RC members is thought to be different from ordinary members, which have over 200 mm thickness. Therefore, evaluation method of flexural capacity for thin RC members is in great demand. In this study, fracture processes of thin RC beams, which have 40, 70 and 100 mm thickness are studied experimentally under the four point bendin g tests. In addition, numerical ev aluation method for flexural capacity of thin RC members is developed and discussed. In the numerical method, tension softening of concrete is considered for each hight such as 40, 50 and 70 mm by fracture energy tests of concrete. As a result, it is found that reinforcement bars in thin RC beam don't perform mechanically as a ordinary RC beams. As for tension softening, 1/3 model of tension softening is adapted for RC beams which have under 70 mm thickness, 1/4 model of tension softening is applied to RC beam which has 100 mm thickness. Consequently, it is realized that the numerical method for flexural capacity of thin RC beams has good performance by taking into account tension softening of concrete.