T298 Landslides, Debris Flow, and Rock Fall: Processes and Hazards II

Wednesday, 28 September 2016
1:30 PM - 5:30 PM
Room 303

ASSESSMENT OF ROCKFALL IMPACTS ON BUILDINGS DURING THE 2010-2011 CANTERBURY, NEW ZEALAND EARTHQUAKE SEQUENCE

Paper number: T298-5
Program: Technical Sessions
Time: 2:35 PM – 2:50 PM

Authors

Abstract

Rock-slope failures during the 2010-2011 Canterbury (Christchurch), New Zealand Earthquake Sequence caused 5 fatalities and resulted in an estimated US$400 million of damage to buildings and infrastructure. Here we present a study if over 30 structures impacted by seismically induced rock fall in the Port Hills region of Christchurch, New Zealand. The consequences of rockfall impacts on structures, taken as both penetration distance into structures and building damage footprint, are shown to follow a power-law distribution with impact energy. Detailed mapping of rock fall sources and paths from field mapping, aerial lidar digital elevation model (DEM) data, and high-resolution aerial imagery provided well-constrained runout paths of boulders. Lumped mass, two-dimensional rock fall runout models were used with high resolution (1-m or better) lidar elevation data to estimate boulder impact velocities and energies. The boulder run out models were based on calibrated surface parameters from mapped runout paths of ~200 additional rock fall runouts. Terrestrial lidar scans generated 3-D point cloud data used to measure structural damage and impacting boulders. The case histories and resulting fragility curves serve as a quantitative basis for risk assessment of rock fall hazards by linking vulnerability data to the predicted impact energies from the hazard analysis.

Geological Society of America Abstracts with Programs. Vol. 48, No. 7

doi: 10.1130/abs/2016AM-284175

© Copyright 2016 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.