Abstract. An efficient numerical simulation of the seismic response of single-story single-span Reinforced Concrete (RC) frames strengthened using diagonal tension-tie elements is presented. The developed analysis is based, calibrated and verified on test results of bare and X-braced RC frames subjected to cyclic imposed lateral deformations described in a companion paper.
The dimensional and the reinforcement configurations of the frames represent earlier RC frame structures that have been designed using old Code provisions without consideration of seismic design criteria and. The columns of the RC frames have shear-critical character due to the inadequate amount of stirrups provided and their low height-to-depth ratio (short columns). Therefore, an easy-to-apply strengthening technique using a pair of two steel crossed tensionties (X-type bracing) is applied and examined. For the numerical simulation, the unilateral behavior of the cable elements that undertake only tension stresses is strictly taken into account.Comparisons between the analytical curves derived from the numerical simulation and the experimental ones from the cyclic tests showed a very good agreement.