On the Seismic Response of the Faculty of Architecture and Engineering Building at Tohoku University

Abstract

The Faculty of Architecture and Engineering Building at Tohoku University survived two strong ground motions. This is not surprising because the structure was stiff and strong. What is surprising is that the first ground motion did not cause severe structural damage but the second one caused so much structural damage that the building had to be evacuated and demolished. The damage occurred despite two key facts: (1) the intensities of the mentioned ground motions are understood to have been similar and (2) the building was strengthened after the first motion (and before the second) following stringent standards.

Seismic Damage of a Building Caused by Post-installed Anchors Intended to Increase Shear Strength of Structural Wall

“…In model A, which represented the expected behavior of the building after strengthening using results of this study, damage was most prominent in the third story boundary columns, with no damage above this story. This is consistent with what was observed in the field after the 2011 earthquake (Wang et al 2016).…”

“…21. Based on the record of the accelerometer on the ninth floor, Wang et al (2016) the relationship between the acceleration and the displacement at the accelerometer and showed that the relationship included sudden decreases of the acceleration. The solid line in Fig.…”

“…Nevertheless, during the 2011 Tohoku earthquake the building sustained severe structural damage. This damage was most severe at the bottoms of the shear walls on the third story, particularly in the boundary columns (Suzuki et al 2013;Wang et al 2016). Examples of this damage are shown in Fig.…”

“…In addition to this damage, the anchors installed in 2001 were observed to have experienced cone breakout failures. Wang et al (2016) suggested that discontinuous web reinforcement as a result of the 2001 strengthening program led to a weak (nearly unreinforced) plane at the base of the third story webs where deformation concentrated. They postulated that concentration of deformations at this location led to strain concentration in the reinforcement, and subsequently decreased the drift capacity of the building.…”