The Earthquake Engineering Online Archive

Dynamic properties of an eleven story masonry building

Stephen, Roy M.; Hollings, Jeffrey P.; Bouwkamp, Jack G.; Jurukovski, Dimitar

UCB/EERC-75/20, Earthquake Engineering Research Center, University of California, Berkeley, 1975-07, 57 pages (545.1/S73/1975)

This report describes the experimental and analytical studies of the dynamic behavior of the Oak Center Towers Building, a reinforced masonry structure, eleven stories in height, located in Oakland, California. The 100 ft high building has a overall plan of 85 ft by 200 ft. The building is offset in the middle by approximately 16 ft so that it does not have a pure rectangular plan. The major part of the building is made up of studio apartments which are basically 16 ft by 27 ft in plan. The experimental work consisted of forced vibration studies in which the natural frequencies, mode shapes and damping values are determined. The experimental values are compared to the analytical model results. The fundamental frequencies determined agreed fairly well; however, the higher mode frequencies did not agree as well. Considerable flexibility of the foundation was noted in the experimental studies and by using these displacements in developing the analytical model the agreement in the fundamental modes was achieved.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-75-20.pdf (4 MB)