Since 1962, strong ground motions and earthquake responses of structures have been observed in the major ports in Japan. By the end of December 2005, 7414 accelerograms had been accumulated and analyzed at the Port and Airport Research Institute.
　The strong-motion earthquake observation network in Japanese ports consists of 111 strong-motion accelerographs installed at 60 ports as of December 2005. Sixty-seven accelerographs out of 111 are installed on ground surface, 34 accelerographs are in ground by using bore-hole and the rest 10 are on structures such as quay walls. Currently two types of accelerographs are used in the network, namely, the ERS accelerograph and the SMAC-MDU accelerograph, both of which are of an electrical type equipped with a digital recorder.
　This report presents results of observation and preliminary analysis of records obtained in 2005. ASCII data of the reproduced accelerograms for all the records in 2005 are available on the attached CD in user-friendly CSV format. Also, computer plots of reproduced accelerograms are available on the CD for the records with peak accelerations exceeding 20 Gals. For the records with peak accelerations exceeding 50 Gals, computer plots of reproduced accelerograms, integrated velocities and displacements, Fourier spectra and response spectra are available on the CD.