The 2011 off the Pacific coast of Tohoku earthquake and response of high-rise buildings under long-period ground motions

Abstract

In the afternoon of March 11, 2011, the eastern Japan was severely attacked by the 2011 off the Pacific coast of Tohoku earthquake (the Great East Japan earthquake). Nearly 30,000 people were killed or are still missing by that earthquake and the ensuing monster tsunami as of April 11, 2011. This paper reports some aspects of this devastating earthquake which hit an advanced country in seismic resistant design. It has been reported that long-period ground motions were induced in Tokyo, Nagoya and Osaka. The properties of these long-period ground motions are discussed from the viewpoint of critical excitation and the seismic behavior of two steel buildings of 40 and 60 stories subjected to the long-period ground motion recorded at Shinjuku, Tokyo is determined and discussed. This paper also reports the effectiveness of visco-elastic dampers like high-hardness rubber dampers in the reduction of responses of super high-rise buildings subjected to such long-period ground motions. The response reduction rate is investigated in detail in addition to the maximum response reduction. In December 2010 before this earthquake, simulated long-period ground motions for earthquake resistant design of high-rise buildings were provided in three large cities in Japan (Tokyo, Nagoya and Osaka) and nine areas were classified. Two 40-story steel buildings (slightly flexible and stiff) are subjected to these long-period ground motions in those nine areas for the detailed investigation of response characteristics of super high-rise buildings in various areas.

Unified analysis of kinematic and inertial earthquake pile responses via the single-input response spectrum method

“…However, in Japan, several recorded or simulated ground motions are used as the input motions in the time-history response analysis in the evaluation of the seismic safety of high-rise buildings and the base-isolated buildings and the design response spectrum is not a unique form of the design ground motions. For example, it is well-known [16,17] that long-period ground motions are well represented by the energy spectrum than the ordinary response spectrum. In some buildings, nonlinear inelastic responses are allowed and these responses are difficult to deal with by the modal superposition rules.…”

Energy-Based Seismic Risk Evaluation of Tall Reinforced Concrete Building in Vancouver, BC, Canada, under Mw9 Megathrust Subduction Earthquakes and Aftershocks

“…The spectral content of the ground motion records for three earthquake types can differ significantly due to different earthquake source characteristics in terms of magnitude and distance ( Figure 1C). For instance, the effects of long-duration ground motions on tall buildings have been highlighted for the 2011 Tohoku earthquake (Takewaki et al, 2011). The three earthquake types have different input characteristics.…”

Critical Steady-State Response of Single-Degree-of-Freedom Bilinear Hysteretic System under Multi Impulse as Substitute of Long-Duration Ground Motion

“…The soil types (soil, rock) of recording sites and types of fault mechanisms are other factors for classification. In addition to these two representative ground motions, longperiod ground motions were observed rather recently (Takewaki et al, 2011). The effects of nearfault ground motions on structural responses have been investigated from various viewpoints (for example, Bertero et al, 1978;Kalkan and Kunnath, 2006).…”