Characteristics of Vertical and Horizontal Response Spectra using Accelerations from the Fukuoka Earthquake Series

Kim Jun Kyoung and Oh Tae Seok

Vertical response spectra using the observed ground accelerations from the 14 Fukuoka earthquakes including the main earthquake (2005/03/20; Mw = 6.5), were compared with the horizontal response spectrum, the seismic design response spectra (Regulatory Guide 1.60, 1973) as applied to Korean nuclear power plants and finally, the Korean Standard Design Response Spectrum for general structures and buildings (1997). In total, 89 vertical ground motions of the acceleration type were used for the vertical response spectrum analysis with a normalization method with respect to the peak acceleration value. The results revealed that the vertical response spectrum was strongly dependent on epicentral distance and natural frequency (natural period). Comparison of the vertical and horizontal response spectra revealed various characteristics. Specifically, the average vertical response values were significantly lower than the requirements in the low-frequency bands indicating that the vertical response design standards were sufficiently conservative. However, in bands of 10 Hz or higher, both average and average-plus-STD value response spectra exceeded the Regulatory Guide 1.60 to some degree. The conservativeness of the current design response spectrum in high-frequency bands, 10 Hz or higher, should be reviewed. The results were also compared with the Korean Standard Response Spectrum (500-year recurrence rate) for three soil types (SC, SD, and SE) and this comparison revealed that the vertical response spectra of the average and the average-plus-STD values exceeded the design response spectrum for the SE soil type for nearly all the periods except for 0.1-0.4 and > ~5 s. This finding suggests that the Korean Standard Response Spectrum (500-year return period, seismic province 1, SE soil conditions) is not conservative enough for most periods suggesting that design response spectra should be investigated more carefully. Through qualitative improvements and quantitative enhancement of the observed ground motions, frequency bands should be investigated with regard to the degree of conservatism in the vertical and horizontal design response spectra.

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Emergency Nursing in Mass Casualty Events: Awareness and Preparedness amongst Nurses in Kerala, India

Joseph Joice K., Nair Sylu S. and Pradeepkumar A.P.

Nurses are the largest subgroup of healthcare workforce in emergency. Hence their preparedness and involvement in disaster management is very crucial for the effective management of mass casualty incidents. A questionnaire survey was conducted among nurses in 22 hospitals covering five districts in Kerala state India. Detailed field visits for data collection as well as for personal interaction with health workers were made as a part of the study. The response rate of the random questionnaire survey was 88%. 83.63% of private nurses and 81.13% of government nurses consider their work in emergencies situation as a huge humanitarian responsibility and their job satisfaction is also very high (86.37% of government and 82.87% of private nurses). The nurses in the state are having a moderate knowledge of disaster management and related aspects. About the existing emergency nursing mechanism 52.52% of government and 62.50% of private nurses are satisfied. In the state Kerala, the mass casualty incidents are handled by government hospitals which mean that nurses on the government sector have better experience in mass casualty care than those in the private sector. Though the resources at the public health centers are limited; they are being utilized sincerely and to the maximum possible. Thus in case of an emergency, the PHC would be able to provide dedicated personnel. Better standard operating procedures and incident command systems are essential for better emergency nursing and disaster management training should be included in nursing curriculum.

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