Data Collection of the Seismic Performance of the Building of the Department of Civil Engineering and Architecture at Tohoku University during the Tohoku, Japan, Earthquake of 2011

The Building of the Department of Civil Engineering and Architecture at Tohoku University is a nine-story, reinforced concrete building that was built in 1969. It has a two-story base and a seven-story tower. The total floor area is approximately 9203 square meters (excluding the adjacent building on the West separated by an expansion joint). The structural system of the building consists of structural walls and frames.

The building is instrumented with two accelerometers (model SMAC-MD) located in the first and ninth stories.

This building was subjected to two major earthquakes, the Miyagi-Ken-Oki Earthquake (Mw = 7.7) in June 1978, and the Kobe Earthquake in 1995 (Mw = 6.9). The Miyagi-Ken-Oki earthquake caused small shear cracks and flexural cracks in the main shear walls, adjacent beams and a few columns of the third and fourth stories. About 2.5% of the window glasses broke and furniture overturned. The building was retrofitted in 2001. The retrofit focused in the upper seven stories. The concrete of the webs of the exterior walls in the North-South direction were replaced, a steel 'jacket' was provided to the coupling beams in the interior frames in the North-South direction, eccentric steel braces were provided in the external south frame in the East-West direction, and portions of the floor slab were thickened and reinforced with steel welded wire.

The building withstood the March 11th, 2011 earthquake, but it suffered heavy damage and it will be demolished because the cost of repair was deemed too high. The major damage concentrated at the base of the third story in the external walls in the North-South direction. The boundary elements of these walls were crushed and the reinforcement buckled. The interphase between the original beams and the web of the walls that was cast in the retrofit in 2001 was damaged, the concrete in the beam was crushed and beam reinforcement was exposed. When this survey was done, an emergency retrofit had been done to the boundary elements of the exterior walls in the North-South direction at the base of the third story.