DYNAMIC CHARACTERISTICS OF BUILDINGS ESTIMATED FROM STRONG NOTION RECORDS(Structures)

Vibration Characteristics of High-Rise Steel Building in Shinjuku Skyscraper District Before and After the 2011 Off the Pacific Coast of Tohoku Earthquake

“…The previous research reported that amplitude dependency was observed in the natural periods and damping coefficients 4,5) . Amplitude of a mode in each earthquake is calculated with the use of the identified natural periods and damping coefficients.…”

“…Yokota and others conducted research on regressive analysis of a relation between natural periods and damping coefficients in minute amplitude to relatively large amplitude from the measurement of slight motions, the vibration test, and the observation record of moderate earthquakes of about intensity 4 in connection with steel high-rise buildings with a period of two seconds and over 4) . Kashima and others identified vibration characteristics by analyzing the observation record of strong motions from 1990 to 2004 in 25 reinforced-concrete, steel-reinforced concrete, and steel buildings in the country, and showed a year-to-year change in amplitude dependency of natural periods and vibration characteristics 5) . Yamazaki and others calculated damping coefficients through the application of the RD method to the record from the microtremor measurement in about a dozen buildings of steel and concrete-filled steel tube structures in Aichi Prefecture, and indicated that most of the data were below the assumption made in the course of the design, and that high-mode damping was smaller than calculated data of damping proportional to rigidity 6) .…”

Characteristics of the first‐mode vertical vibration of buildings based on earthquake observation records

“…Many analysis results were reported regarding the vibration characteristics of buildings 1–3,24 . In recent years, studies on natural periods and damping ratios that are related to amplitude dependence, damage dependence, and aging have been published 4–7,25 . However, many of these reports are limited to the horizontal vibration characteristics.…”

“…[1][2][3]24 In recent years, studies on natural periods and damping ratios that are related to amplitude dependence, damage dependence, and aging have been published. [4][5][6][7]25 However, many of these reports are limited to the horizontal vibration characteristics. Few studies have conducted comprehensive analyses of the observation records for various structural types and buildings with respect to the vertical characteristics.…”

Fluctuation Factors in Dynamic Characteristics of a Six-Story Wooden Framing Building

“…From all strong motion data, the fundamental natural frequencies and damping ratios in two horizontal directions of the building were identified using a parameter optimization technique 16) . With a single-degree-of-freedom system, the natural frequency and damping ratio that had the most fitted response acceleration were determined using the grid search.…”