Analysis on acceleration data of dams collected by JCOLD

Securing of the seismic performance of dams is an extremely important issue. As Japan is one of the most earthquake-prone countries in the world, various kinds of efforts regarding the issue have been carried out. In particular, seismic recordings have been conducted in existing dams since they can verify the characteristics of earthquake input and dam response empirically. The seismic records have been utilized for the advancement of dam safety management, design and construction. The strong motion records are highly valuable; however, it takes years, plus a great deal of work and expense, to record such data appropriately. The data can be used more effectively by providing it to other entities or researchers once it has been recorded, and this is commonly understood to conform to the intended purpose of the seismic recordings. It will also contribute to the further advancement of seismic safety evaluation and the design of dams. The Japan Commission on Large Dams (JCOLD) released databases of earthquake recordings in 1978 (Earthquake Records on Rock Foundations, 1978.11) and 2002 (Acceleration Records on Dams and Foundations No.2, 2002.4). In view of this background, the Japan Commission on Large Dams, with support from dam owners and other interested parties, has organized the committee on “Acceleration Records on Dams and Foundations” and updated the dam earthquake records database to promote technical improvement and the advancement of evaluation of the seismic performance of dams and dam engineering. The JCOLD committee has collected these time histories of accelerations, recorded from October 2000 to September 2012 newly. The recordings in data book titled “Acceleration Records on Dams and Foundations No.3” were restricted to acceleration records at dam foundations, dam crests, ground and so on whose peak acceleration at the dam foundation exceeds 25 cm/s. They include data which were recorded before the target collection period. In addition to the above activity, the JCOLD committee has carried out analysis of fundamental strong motion characteristics at dam sites, acceleration response characteristics of dams, and natural periods of dams and so on. This tentative report show the outlines of data book of “No.3” and the characteristics of acceleration data of dams and foundations.