Methodology for the assessment of the damage cost resulting from a large earthquake in the vicinity of Wellington

Abstract

At the request of the Earthquake and War Damage Commission, the New Zealand National Society for Earthquake Engineering set up a study group to determine the maximum probable loss the Commission may suffer by way of claims resulting from a large earthquake with its epicentre near Wellington. The study group's task was to determine the order of cost of physical damage to buildings and their contents which could credibly be expected to result from large earthquake attack. Seismic loss information for New Zealand conditions is minimal and it was therefore necessary to critically review published overseas data. Where appropriate, adjustments were made to accommodate New Zealand conditions. Loss information was compiled as the ratio of damage cost to building value and varied with felt earthquake intensity as well as with type of building construction. The total value and structural classification of the building stock in the affected area was compiled and entered on a computer. A program was set up to enable loss calculations to be carried out for the appropriate building classification and for the relevant earthquake intensities. From this the total loss was calculated. The results of the study expressed as monetary loss are confidential to the Earthquake and War Damage Commission. In this paper, therefore, results are not presented in absolute dollar terms, but are given as relative values.