Damage ratios for domestic property in the magnitude 7.2 1968 Inangahua, New Zealand, earthquake
DOI:
https://doi.org/10.5459/bnzsee.34.3.191-213Abstract
An analysis of damage costs to domestic property in the Mw 7.2 Inangahua, New Zealand, earthquake of 23 May 1968 (U.T.) has allowed the evaluation of the vulnerability of domestic property for six intensity zones, from MM5 - MM10 inclusive. For no other earthquake worldwide has the vulnerability of any class of property been examined in so many intensity zones, and the effect of brittle chimneys on damage levels has been fully evaluated for the first time. The relative vulnerability of one and two storey houses has also been evaluated. The costs of damage were derived from about 8,000 insurance claims to the Earthquake and War Damage Commission. Damage ratios were evaluated for houses and their contents as functions of Modified Mercalli intensity. The indicators of vulnerability that were determined were the statistical distributions and mean values of damage ratios and the percentage of property items damaged for the six intensity zones. Comparisons have also been made with results from studies of other earthquakes.
References
Dowrick, D.J., and Rhoades D.A. (1998), "Magnitudes of New Zealand earthquakes, 1901 - 1993", Bulletin NZ National Society for Earthquake Engineering, 31(4), 260-280. DOI: https://doi.org/10.5459/bnzsee.31.4.260-280
Anderson, H., Beanland, S., Blick, G., Darby, D., Downes, G., Haines, J., Jackson, 1., Robinson, R. and Webb, T. (1994), "The 1968 May 23 Inangahua, New Zealand, earthquake: an integrated geological, geodetic, and seismological source model", N.Z. J. Geol. Geophys., 37, 59-86. DOI: https://doi.org/10.1080/00288306.1994.9514601
Dowrick, D.J., and Sritharan, S. (1993), "Peak ground accelerations recorded in the 1968 lnangahua earthquake and some attenuation implications", Bulletin NZ National Society for Earthquake Engineering, 26(3), 349-355. DOI: https://doi.org/10.5459/bnzsee.26.3.349-355
Adams, R.D.. Eiby, G.A., Lowry, M..A., Lensen, G.J., Suggate, RP., and Stephenson, W.R. (1968), "'Preliminary reports on the Inangahua earthquake, New Zealand, May 1968", Bulletin 193, New Zealand Department of Scientific and Industrial Research.
Dowrick, D.J., Gibson, G., and McCue, K. (1995), "Seismic hazard in Australia and New Zealand", Bulletin NZ National Society for Earthquake Engineering, 28(4), 279-287. DOI: https://doi.org/10.5459/bnzsee.28.4.279-287
Dowrick, D.J., and Rhoades, D.A., (1990), "Damage ratios for domestic buildings in the 1987 Edgecumbe earthquake", Bulletin NZ National Society for Earthquake Engineering, 23, 137-149. DOI: https://doi.org/10.5459/bnzsee.23.2.137-149
Dowrick, D.J. (1991), "Damage costs for houses and farms as a function of intensity in the 1987 Edgecumbe earthquake", Earthquake Engineering and Structural Dynamics, 20, 455-469. DOI: https://doi.org/10.1002/eqe.4290200506
Dowrick, D.J., Rhoades, D.A., Babor, J., and Beetham, R.D. (1995), "'Damage ratios and microzoning effects for houses in Napier at the centre of the magnitude 7.8 Hawke's Bay, New Zealand, earthquake of 1931", Bulletin NZ National Society for Earthquake Engineering, 28(2), 134-145. DOI: https://doi.org/10.5459/bnzsee.28.2.134-145
Dowrick, D.J., and Rhoades, D.A. (1997), "Vulnerability of different classes of low-rise buildings in the 1987 Edgecumbe, New Zealand, earthquake", Bulletin NZ National Society for Earthquake Engineering, 30(3), 227-241. DOI: https://doi.org/10.5459/bnzsee.30.3.227-241
Dowrick, D.J., and Rhoades, D.A. (1997), ''Inferences for design, insurance and planning from damage evaluation in past New Zealand earthquakes", Journal of Earthquake Engineering, 1(1), 77-91. DOI: https://doi.org/10.1080/13632469708962362
Rhoades, D.A., and Dowrick, D.J. (1999), "'Variability of damage ratios for property in earthquakes". Earthquake Spectra, 15(2). 297-316. DOI: https://doi.org/10.1193/1.1586042
Grant-Taylor, T.L., Adams, R.D., Hatherton, T., Milne, J.D.G., Northey, R.D., and Stephenson, W.R. (1974), "Microzoning for earthquake effects in Wellington, N.Z." New Zealand Department of Scientific and Industrial Research, Wellington, Bulletin 213.
Luke, K.E. (1943), "City of Wellington, N.Z. Report on damage by earthquakes". (Unpublished) City Engineer's report to Wellington City Council.
Rojan, C. and Sharpe, R.L. (1985), "Earthquake damage evaluation data, ATC-13". Applied Technology Council, California.
"The New Zealand Census 1966", Department of Statistics, New Zealand.
Bird, D.I.D. (1969), "Insurance assessments in lnangahua". Bulletin NZ Society for Earthquake Engineering. 2(1), 111-112.
Suggate, RP . and Wood, P.R. (1979), "lnangahua earthquake - damage to houses", Report N.Z.G.S. 85, New Zealand Geological Survey, Department of Scientific and Industrial Research.
"The New Zealand Official Year Book 1969", Department of Statistics, New Zealand.
Various authors (1968), "The 1968 lnangahua earthquake", Conference seminar papers, Bulletin NZ Society for Earthquake Engineering, 1(2). 4-96.
Various authors (1969), "A preliminary report on the Inangahua earthquake New Zealand, May 24, l968", Bulletin NZ Society for Earthquake Engineering, 2(1), 9-148.
Shepherd, R., Bryant, A.H., Carr, A.J., Dodd, T.A.H., Gordon, D.R., Moss, P .J., and Sutherland, A.J. (1970), "The 1968 Inangahua earthquake", Canterbury Engineering Journal, 1, 2-86.
Dowrick, D.J. (1996), 'The Modified Mercalli earthquake intensity scale - Revisions arising from recent studies of New Zealand earthquakes". Bulletin NZ National Society for Earthquake Engineering, 29(2), 92-106. DOI: https://doi.org/10.5459/bnzsee.29.2.92-106
Downes, G.L., Dowrick, D.J., Van Dissen, R.J., Taber, J.J, Hancox, G.T., and Smith, E.G.C. (2001), "The 1942 Wairarapa, New Zealand, earthquakes: analysis of observational and instrumental data". Bulletin NZ Society for Earthquake Engineering, 34(2), 125-157. DOI: https://doi.org/10.5459/bnzsee.34.2.125-157
