Abstract
In this paper, a step by step calculation method is presented, which is applied to pursue the process that a reinforced concrete structure approaches to failure gradually. This method is a finite element method and the assumptions taken into the analysis are as follows : (1) The reinforcement is a bar bearing only the axial force, and being arranged among the nodes at the four corners of a concrete model element. The stress-strain curve of the bar is expressed as the elastoplastic relationship in tension and compression. (2) The rectangular truss element with two diagonal members, that is the same in the Lattice Analogy, is used for the no cracked concrete element, and after a crack occurred the orthogonal aeolotropic plate element is used. In this case, the crack occurres when the maximum principal stress at the center of the element is over a limit value. In compression, tri-liniear the yield is caused on the minimum principal stress, and the stress-strain characteristics is expressed as a liniear-quadratic type. Therefore, the concrete and the bar are bonded together perfectly, until a crack is detected in the concrete element. In order to demonstrate the accuracy obtainable by this method based on those assumptions, five examples are selected. As the results, it is proved that the solutions obtained with those model agree fairly well with the experimental test results.
