Long-term Changes in Vibration Characteristic of the Traditional Wooden House Based on Microtremor Measurement

2018 Fiscal Year Final Research Report

• Project/Area Number: 17H06932
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Building structures/Materials
• Research Institution: Kyushu University
• Principal Investigator: NAMBU Yasuhiro 九州大学, 人間環境学研究院, 助教 (80802298)
• Project Period (FY): 2017-08-25 – 2019-03-31
• Keywords: 伝統木造住宅 / 茅葺 / 常時微動計測 / 固有振動数 / 振動モード / 水平剛性

Outline of Final Research Achievements

This paper reports the influence of Geya and thatched roof on vibration characteristic based on the result of structural investigation and microtremor measurement of the traditional wooden house with thatched roof. We create the analysis model by replacing each plane of structure with multi-mass shear system and perform eigenvalue analysis with the value of kh (the rigidity of the horizontal structure) / kv (the rigidity of the vertical structure) as a parameter. Our conclusion are as follows. 1) Primary natural frequency is 2.7 Hz in the inter-beam direction and 3.4 Hz in the longitudinal direction. 2) In the the inter-beam direction, it is inferred that Extended Geya does not vibrate coupled with Omoya and the value of kh / kv is about 1.0. In the longitudinal direction, it is inferred that it is inferred that Conventional Geya vibrate coupled with Omoya and the value of kh / kv is about 1.0 to 2.0.

Free Research Field

木質構造

Academic Significance and Societal Importance of the Research Achievements

一般に建築物の耐震性能や振動特性を評価する上で、鉛直構面の耐力要素をつなぎ水平力を各鉛直構面に伝達する役割を有する水平構面の構造性能を把握することは重要である。一方、様々な構法がみられる伝統構法の建築物においては、屋根や床といった水平構面の構造性能に関する研究の蓄積は十分とは言えず、耐震診断や補強時にその性能を想定するのが難しい現状がある。そこで、本研究では、茅葺屋根を有する伝統木造住宅を対象として、茅葺屋根の構造性能を推定を簡単・低コストかつ非破壊で実施可能である常時微動計測を用いた。