Study on practical application of the CCA method, a new analysis method for array observations of microtremors

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560688
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Building structures/materials
• Research Institution: Kyushu University
• Principal Investigator: KANNO Tatsuo 九州大学, 人間・環境学研究科(研究院), 教授 (80363026)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 微動アレー観測 / 地下構造 / CCA法 / SPAC法

Outline of Final Research Achievements

Analysis results for observed microtremors by the CCA method were compared with those by the SPAC method, and the following knowledge was provided.
1. When the array of the small radius is used, the CCA method shows superior estimation ability of the phase velocity, but with the array of radius of more than 100m, ability of both methods does not have the difference. 2. When the same array radius is used, the frequency band of the Rayleigh wave where the CCA method can estimate phase velocity shifts to the low frequency side, and, the SPAC method have higher ability of analysis in the high frequency range. 3. The combination of both methods widens a frequency range of the estimated phase velocity. 4. If the SN ratios of the observed microtremors are managed appropriately, the CCA method can reduce the array radius of approximately 100m to 20-40m.

Free Research Field

地震工学