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Since 1995, seismic isolation structures have been applied effectively to buildings whose superstructure is characterized to have a long fundamental period such as steel-framed and high-rise buildings. However, for logistics warehouses which are designed to be long span and a high floor height to create a large internal space, there is a possibility that such buildings will not deform as expected. This study proposes a response prediction formula for base-isolated building by using period ratio between the superstructure and the seismic isolation layer.

Past study had proposed a design method for base isolated structure considering tensile strain. Therefore, this paper proposes a method to predict the tensile strain of laminated rubber bearings and the moment of beams due to superimposed horizontal and vertical responses using constant energy rule. This proposed method considers that the tensile modulus of rubber bearing is lower than its compression modulus.

This paper proposes a method to predict the response of high-rise buildings with dampers subjected to multi-segment earthquake by the single earthquakes. Time-history analyses of high-rise building models with dampers are carried-out for multi-segment earthquake and single earthquake responses. By these analyses, a method is proposed to predict the maximum response and cumulative damage from multi-segment earthquake by using single earthquakes. The proposed prediction method is verified by comparing its results with those of seismic response analysis.

In the 2011 off the Pacific coast of Tohoku Earthquake, as cargoes in warehouses fell on the floor, their contents and the automated conveying equipment were significantly damaged. Recently, some countermeasures have been proposed. However, it takes time for deciding the capacities of these countermeasures because dynamic analysis should be conducted for each case of their introduction to warehouses. Simplified method of evaluating the cargo fall is required for effective decision of their capacities. This paper proposes the energy balance method for evaluating cargoes slip displacement which is the key factor of cargo falling.

In recent years, demand for large logistics facilities is rising under the influence of expansion of retail chain development and online market. Most of these facilities are low- and middle-rise steel structures, and it is vital that these structures are earthquake resistant. An energy-based method for earthquake-induced response of a building is very useful for the evaluation of the cumulative damage of structures. However, this method is not applied to structures with uneven stiffness distribution in the height direction like large logistics facilities. In this paper, we analyze whether this method can be expanded to such structures by comparing cumulative damage distribution predicted using this method and calculated by time-history analysis. Moreover, the effect of difference in strength calculation on cumulative damage distribution prediction is examined.

The Miner’s rule that is used as the damage evaluation method for the random waveform requires time-consuming waveform decomposition. It is effective to estimate the damage index from only maximum amplitude and energy absorption without waveform decomposition. It is known that the relationship between maximum deformation and cumulative plastic deformation is correlated with the repetition number f value that characterizes the seismic ground motion. In this paper, the simplified damage evaluation method using the average amplitude associated with the maximum amplitude based on f value is proposed.

A vibration control system for an automated warehouse was developed that can be applied to existing warehouses as well as newly built ones. The device used for this system is the “postinstalled mass damper” that can be post installed on the cargo storage space in an automated warehouse. This damper has a large mass that causes a sustainable effect of reducing the response across a wide range of natural frequencies of an automated warehouse, which vary depending on the number of stacked cargoes and their weight. The results of the shaking table test demonstrated that the fall of cargoes by the earthquake ground motion could be prevented by using this damper because the accelerations of the rack were reduced to 50%-70%. Moreover, this effect was confirmed by the analysis conducted with the proposed model. The acceleration of the rack top was reduced to 80% and the maximum slip displacement of the cargoes was reduced to 25%.

Performance degradation of the response control device is caused by bending deformation. Therefore, the authors proposed amplification mechanism that functions to bending deformation. In order to improve this amplification mechanism, this paper proposes new response control system which is used in combination with the amplification mechanism and seismic brace. The usefulness of this system evaluate from time history analysis results and static analysis results. Evaluation of the response control performance is using the frame parameters obtained from two-types of static analysis results. Frame parameters can estimate the ratio of the effective damper deformation as evaluation index of performance. The validity of this evaluation method is demonstrated by comparing with the dynamic response analysis results.

In our previous study, we proposed the new structural system which amplifies effective damper deformation, and showed the amplification of damper deformation and the high damping effect by the analysis for high-rise building. However, this study has yet to show the amplification effect of the effective deformation in the experiment. In this paper, the amplification of damper deformation in the proposed system are confirmed by the dynamic vibration tests. In addition, to investigate the influence of damper location, tests are conducted on 2 types of specimens varying in damper location.

In recent years, seismic isolation buildings are becoming taller and the shape has become more diversified. Therefore, the tensile strain of laminated rubber bearing (LRB) is important. A method of defining the tensile limit of LRB by tensile strain has been proposed, and it is necessary to correctly evaluate the tensile strain generated in LRB due to horizontal and vertical earthquake motions. To evaluate the tensile strain occurring in LRB, it is desirable to perform a time history analysis in which horizontal and vertical are input simultaneously. However, the tensile strain of LRB is affected significantly by the damping setting of the building and the nonlinear characteristics of LRB. Therefore, a detailed examination is required. We propose the estimation method of tensile strain for LRBs using the superposition of horizontal and vertical response values considering that the tensile elastic modulus of LRBs is lower than its compression modulus. In addition, we propose the estimation method of bending moment for a foundation beam when the LRBs are pulled out. The validity of the proposed methods is demonstrated by comparing them with the time-history analysis results using a 24-story isolated base building model.