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Yasuda Y.,Kanagawa University | Sekine H.,Kanagawa University | Watanabe K.,Urban Renaissance Agency | Yabushita M.,YAB Corporation | Horiuchi H.,YAMAGUCHI Corporation
Journal of Environmental Engineering (Japan) | Year: 2014

There are a lot of old apartment buildings with thin floor slabs, which cause low ability to insulate heavy-weight floor impact sound. The authors have developed a high-sound-insulation double floor system with Helmholtz resonators, as part of renovation of these buildings. In the present paper, some types of double floor system including the proposed one are simply modeled as one- or twoparticle systems, and their vibration characteristics are investigated. Calculation results based on these models clarify the effects of a variety of parameters for the double floor systems, particularly, on the positions of their natural frequencies. The tendencies of the calculation results are in good accordance with those measured in a laboratory. The proposed double floor system greatly improves the insulation performance for heavy-weight floor impact sound, about 10 dB for 63- and 125-Hz octave bands, in a real old apartment building, the slab thickness of which is 110 mm.

Yamane Y.,Tokyo University of Science | Nagano M.,Tokyo University of Science | Hida T.,University of Tokyo | Tanuma T.,Urban Renaissance Agency
AIJ Journal of Technology and Design | Year: 2016

This report describes height-wise distribution of maximum interstory drift angles in super high-rise RC buildings based on earthquake response analysis models for structural design. Yielding loads in the restoring force characteristics are almost consistent for plural buildings when normalized by base shear coefficients. The height-wise distributions of interstory drift angles mainly depends on characteristics of input wave motions. As a result of the response analyses using various pulse waves and harmonic waves, the maximum interstory drift angles in low level floors occur when predominant period of input wave is longer than first natural period of the building.

Ando S.,Sumitomo Osaka Cement | Yamada H.,Sumitomo Osaka Cement | Nakano K.,Chiba Institute of Technology | Hamasaki H.,Shibaura Institute of Technology | Tanuma T.,Urban Renaissance Agency
AIJ Journal of Technology and Design | Year: 2015

The tensile creep test of the post-installed anchor was carried out by the improved spring type creep test equipment. The measurement of creep deformation from non-load and creep fracture time was possible over a long period of time by this equipment. The creep deformation at about 1/3 load of the maximum load increase slightly for the duration of 90 day, but the creep deformation is very small, and creep fracture will not occur in 50 years. And at 80% of the maximum load, creep fracture occurred in 168 days.

Toriumi Y.,Polytechnic University of Mozambique | Kurabuchi T.,Tokyo University of Science | Kodera S.,Urban Renaissance Agency
Journal of Environmental Engineering | Year: 2012

Research questionnaire was carried on the usage of housing equipment focusing on the continuous ventilation system in apartmenthouses. It was confirmed that ventilation systems are operated 24 hours more than 80% of the respondents, and the operating ratio increases as the household number increasing.On the other hand, the ratio of opening outdoor air inlets for ventilation system was as low as about 50%. Cross correlation analysis showed that the operation of continuous ventilation system is effective in suppressing dew condensation, mold and bad smell, and the majority of respondents evaluate the ventilation system satisfactorily. Separate analysis by age revealed that aged households are very sensitive on utilities expense and tend to apply local heating of a room and bathing is not frequent.

Uebayashi H.,Kyoto University | Nagano M.,Tokyo University of Science | Hida T.,University of Tokyo | Tanuma T.,Urban Renaissance Agency | And 2 more authors.
Earthquake Engineering and Structural Dynamics | Year: 2016

Evaluation of the degrees of structural damage suffered by high-rise residential buildings after being subjected to strong ground motions is extremely important to the development of life continuity planning for building residents. However, these evaluations cannot be based on strong-motion records alone, because earthquake observation equipment is not installed in most such buildings in Japan. In this study, we propose simple equations for estimating the stiffness degradation rate and the peak inter-story drift ratio (PIDR) by using ambient vibration records instead of strong-motion records when high-rise RC buildings are subjected to a severe earthquake. More specifically, we propose one equation that relates the square root of the stiffness degradation rate, which is the ratio of natural frequencies at the maximum response to the preliminary tremor response (elastic state), in strong-motion records with the ratio of natural frequencies identified from ambient vibrations before and after damage was suffered. We also propose an equation that relates the PIDR with the stiffness degradation rate on the basis of the stiffness-degrading bilinear restoring force characteristic derived from the strong-motion records of 13 high-rise buildings for the 1995 Hyogoken-Nanbu Earthquake (Mw 6.9) and the 2011 Tohoku-Oki Earthquake (Mw 9.0). © 2015 John Wiley & Sons, Ltd.

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