Abstract
This study proposes a disaster resilient structural design of reinforced concrete buildings with ordinary construction approach, and demonstrates the seismic capacity by the full-scale test on five-story reinforced concrete buildings. In this design, the building produces base shear coefficient higher than 0.55 by utilizing wing wall, spandrel wall, and hanging wall. The target damage level under extreme ground motion is less than slight for buildings, and grade I for each member. This method improves the strength and stiffness of the moment resisting frame and reduces the deformation during earthquakes. That can minimize the damage on each member.
The full-scale specimen is a five-story reinforced concrete building with 1×2 bays and height of 18.7m. The wall frame has large openings in the longitudinal direction. The span length is 6.0m and story height is 3.5m. Columns have 700 mm square section, and beams have 500×700 mm section. The width of the attached wall section is 200 mm. A series of 4 actuators located on the roof level and 6 actuators located on the 4th-floor level. Those actuators pinched the center of the floor slab from the upper and lower level. The relation between base shear and the overturning moment is given by a ratio of external force on the 4th floor and roof is equalize to that given by an external force with inverted triangle load distribution. The cyclic loading peak is controlled by the total drift on the roof level. The test demonstrates the up to 3.0 times over calculated strength of base shear coefficient 0.3 of bare- frame. The story drifts are concentrate prominent on 2nd and 3rd floor and its collapse mechanism form the partial collapse. The strain of the main reinforcement of the bare-frame yielded in the 0.5% total drift loading cycle, where a limit of elastic is 0.25% total drift loading cycle. The damage levels based on the residual seismic capacity on the hysteretic curve is slight at 0.25% total drift loading cycle, and the base shear coefficient at the 0.25% total drift loading cycle is 0.67.
