Statistical Modeling of Fire Occurrence Using Data from the Tohoku, Japan Earthquake and Tsunami.

In this article, we develop statistical models to predict the number and geographic distribution of fires caused by earthquake ground motion and tsunami inundation in Japan. Using new, uniquely large, and consistent data sets from the 2011 Tohoku earthquake and tsunami, we fitted three types of models-generalized linear models (GLMs), generalized additive models (GAMs), and boosted regression trees (BRTs). This is the first time the latter two have been used in this application. A simple conceptual framework guided identification of candidate covariates. Models were then compared based on their out-of-sample predictive power, goodness of fit to the data, ease of implementation, and relative importance of the framework concepts. For the ground motion data set, we recommend a Poisson GAM; for the tsunami data set, a negative binomial (NB) GLM or NB GAM. The best models generate out-of-sample predictions of the total number of ignitions in the region within one or two. Prefecture-level prediction errors average approximately three. All models demonstrate predictive power far superior to four from the literature that were also tested. A nonlinear relationship is apparent between ignitions and ground motion, so for GLMs, which assume a linear response-covariate relationship, instrumental intensity was the preferred ground motion covariate because it captures part of that nonlinearity. Measures of commercial exposure were preferred over measures of residential exposure for both ground motion and tsunami ignition models. This may vary in other regions, but nevertheless highlights the value of testing alternative measures for each concept. Models with the best predictive power included two or three covariates.

The Marmara, Turkey earthquake of August 17, 1999 : Reconnaissance report

This report includes observations from reconnaissance trips sponsored by the MCEER to Turkey after 7.4 eartquake on August 17, 1999. It is the product of many authors representing several disciplines and, while not a final assessment to the topics addressed, represents an interim earthquake engineering evaluation of the natural, built and social environments. As noted by several of the authors, the analogies between the North Anatolian Fault Zone in Turkey and the San Andreas Fault in the United States are strkingly similar. The observations and conclusions herein form a springboard for future collaborative research efforts, which advance society's ability to better withstand the destruction caused by earthquake throughoug the world

Section 7 : Lifeline performance

This section reports on impacts of the August 17, 1999 earthquake on water, power and gas utilities, based on field surveys conducted on August 24-25, 1999. Because services such as water and power are vital for the function of an urban region, they are referred to as lifelines. In general, lifelines performed well in this earthquake, especially the source and transmission elements. Distribution systems, however, were more severely damaged, especially the underground water system pipin in the high intensity areas

Seismic reliability assessment of critical facilities : A handbook, supporting documentation, and model code provisions

This document summarizes a multi-year research project in the development of a detailed methodology to assess and improve the functional reliability of equipment systems in critical facilities following earthquakes. It is inended to be used by engineers, building officials, owners and other individuals interested in assessing and impoving the capability of a facility to provide critical services. The methodolgy described intends to improve the reliability of equipment systems and make it flexible enough to be used in many types of facilities and does not require personnel with seismic expertise. The approach to this methodogy is simple: 1. Systems definition. 2.Evaluation of individual components. 3. Systems evaluation. 4. Risk management, make decisions

Reliability - based design of water supply systems

Water supply systems are vitally required for day-to-day existence, for commercial and industrial operations, and for emergency firefighting. Loss of water supply during earthquakes has led to conflagrations and catastrophic losses, which would have been avoided give an assured water supply. Recent experience in the 1994 Northridge and 1995 Hanshin earthquakes have emphasized the concept that water supply systems will inevitably sustain damage in earthquakes. Although all damage cannot be avoided, reliable water supplies can be assured, via an optimum design program involving robust hardware, redundant supplies and networks, real-time control systems, and alternative flexible emergency response resources. These techniques have been employed in several recent projects, in an effort to assure reliable water supplies for urban regions. Each case was unique, but all projects began with identification of existing vulnerabilities and determination of the system's perfomance criteria. The optimum program for each project varied, but incluided (a) provision of a hardened "backbone" system, for Contra Costa Water District, (b) design of a redundant multi-use network, for the San Francisco Auxiliary Water Supply System (AWSS)-Reclaimed Water (RCW) extension project, (c) development of a radio-controlled block isolation system, for the existing AWSS, and (d) design of a new Dedicated Fire Protection System, for the City empirical and analytical methods, and incorporating these criteria in an overall reliability/optimization framework. The result was a clearer understanding of system needs, and a seismically robust, cost-effective design.(AU)

Training local officials in rapid visual screening of seismically hazardous buildings

Thirty local officials from the Central United States were given a 2 - day seminar in the methodology of ATC-21: Rapid visual screening of buildings for potentialk seismic hazards. The ATC-21methodology comprises a "sidewalk survey" using a rapid assessment from to identify buildings that may pose significant seismic risk; each structure can be assessed in 30 minutes or less (AU)

A model methodology for assessment of seismic vulnerability and impact of disruption of water supply systems

A practical simplified model methodology assessment of vulnerability and impact of failure and disruption for water supply system is presented in this paper. The model methodology consists of four major steps: 1)System Inventory, involving the determination of key system component attributes, such as location, materials of construction, seismic vulnerability, etc 2)Identify Seismic Hazards, involving the identification of active earthquake faults, potentially liquefiable soils, and similar earthquake hazards 3)Estimation of Impact of hazard on System Component, involving determination of key component potential damage and reduced functionality, due to identified seismic hazards, 4)System Analysis, involving estimation of losses due to direct damage to components and estimation of reduced system functionality, in terms of residual capacity and time-to-restoration (AU)

Mitigation and damage to the built environment - v.2

A practical simplified model methodology assessment of vulnerability and impact of failure and disruption for water supply system is presented in this paper. The model methodology consists of four major steps: 1)System Inventory, involving the determination of key system component attributes, such as location, materials of construction, seismic vulnerability, etc 2)Identify Seismic Hazards, involving the identification of active earthquake faults, potentially liquefiable soils, and similar earthquake hazards 3)Estimation of Impact ofhazard on System Component, involving determination of key component potential damage and reduced funtionality, due to identified seismic hazards, 4)System Analysis, involving estimation of losses due to direct damage to components and estimation of reduced system funtionality, in terms of residual capacity and time-to-restoration

Liquefaction study, sullivan marsh and mission creek, San Francisco, California

This paper describes the geotechnical aspects of liquefaction failures in two areas of San Francisco. Utility perfomance during the two earthquakes is discussed in a companion paper appearing elsewhere in these proceedings. Both papers are based on the results of a liquefaction atudy perfomed for the city and County of San Francisco.(AU)

Utility perfomance aspects, liquefaction study, marina and Sullivan marsh areas, San Francisco, California

This paper reports on vulnerability measures of underground piping subjected to area-wide deformations, and the spectrum of mitigation measures developed as part of this project. Due to limitations of space, only two of the areas studied, the Marina and Sullivan Marsh areas, are discussed. In order to do this, we next describe the underground utility systems considered as part of this project, summarize our evaluation of utility damage, and review the mitigation options developed for the project.(AU)

Earthquakes and residential construction in Japan

While much effort has been spent on analysis of individual structures, building class seismic damage estimators for earthen buildings in seismic zones, of value in disaster planning, code-writing, city planning, national hazards policy formulations etc., have been little investigated. Damage ratios for onset of damage and collapse and for cost of damage are found to correlate best with response spectra at 0.7 s. Using published test data and average building properties, a seismic damage model explains the low-rise building behaviour and permits examination of the effect of structural change ont the estimated damage (AU)