ANALYSIS OF DAMAGED CONCRETE FRAME BUILDINGS

This dissertation presents a general analysis procedure for simulating the earthquake response of reinforced concrete frame buildings, which may or may not have been damaged during previous exposures to strong ground motions. The establishment of this analysis procedure requires the completion of the following tasks: (1) The accurate modeling of the behavior of general reinforced concrete frame members subjected to strong cyclic loads; (2) The definition of a damage parameter, which correlates well with the structure's residual strength and stiffness, and which is suitable for subsequent reliability analyses; (3) The establishment of a procedure for the dynamic analysis of damaged concrete frames.; A theory for a new mathematical model of frame members is developed and its accuracy is verified by simulating various experiments for which data were available in the literature. New local and global damage parameters are defined, and a procedure for analyzing damaged frames is outlined. Herein it is assumed that the building's fundamental frequency is known or can be determined in post-earthquake field measurements. The analysis procedure is verified by reproducing some shaking table tests that had been carried out at the University of Illinois. Some interesting albeit preliminary conclusions could be drawn from these limited studies: (1) The accuracy of the new frame member model is excellent for practical purposes; (2) The proposed definitions of damage parameters are useful and reliable indicators for damage states; (3) The agreement between experimental measurements and theoretical response predictions for damaged concrete frame is remarkable.