AMERICAN JOURNAL OF ENGINEERING AND APPLIED SCIENCES, cilt.3, sa.1, ss.109-116, 2010 (Hakemli Dergi)
Inadequate attention during design and construction of some of
Reinforced Concrete (RC) buildings in North Cyprus has raised questions about the performance level
of these existing buildings under future earthquakes. Approach: Column jacketing, adding steel braces
and new shear walls to an existing building are common strengthening methods used by practical
engineers in North Cyprus to increase the performance level of an existing building. Results: The aim
of this study was to determine the most effective strengthening method among these three mentioned
techniques. As a case study, a four stories RC existing building was selected and assessed using finite
element method. To remodel of the existing building, the survey works done included three main
steps, detecting the reinforcement bars for beams and columns, actual used concrete strength and
soil type. The beams and columns reinforcement bars were determined using Ferro scan method and the
soil was sampled in Girne city to determine the soil type. The actual concrete strength was determined
using core test. Three common strengthening techniques mentioned above, were applied to the existing
building. Then the efficiency of each strengthening method was investigated on the basis of removing
of weak columns, not-safe beam-column joints in shear and performance levels based on the
FEMA356 and Turkish earthquake code. Conclusion/Recommendations: Results showed that column
jacketing is the most effective method to remove the weak columns and not-safe column-beam joints
in shear. Nonlinear static pushover results showed that despite that adding shear walls caused an
increase in the structural base shear and a reduction in the maximum roof displacement and the number
of collapsed elements at FEMA356 performance point, but it caused a remarkable reduction in the
building ductility ratio. Finally, results showed that the column jacketing is the most effective and the
most economic strengthening technique for the low-rise residential buildings in North Cyprus.