Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Nat. Hazards Earth Syst. Sci., 17, 703-719, 2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
17 May 2017
Examining the impact of lahars on buildings using numerical modelling
Stuart R. Mead1,2,3, Christina Magill1, Vincent Lemiale2, Jean-Claude Thouret4, and Mahesh Prakash2 1Risk Frontiers, Department of Environmental Science, Macquarie University, Sydney, Australia
2Commonwealth Scientific and Industrial Research Organisation, Clayton 3168, Victoria, Australia
3Volcanic Risk Solutions, Institute of Agriculture and Environment, Massey University, Private Bag 11 222, Palmerston North, New Zealand
4Université Clermont Auvergne, CNRS, IRD, OPGC, Laboratoire Magmas et Volcans, 63000 Clermont-Ferrand, France
Abstract. Lahars are volcanic flows containing a mixture of fluid and sediment which have the potential to cause significant damage to buildings, critical infrastructure and human life. The extent of this damage is controlled by properties of the lahar, location of elements at risk and susceptibility of these elements to the lahar. Here we focus on understanding lahar-induced building damage. Quantification of building damage can be difficult due to the complexity of lahar behaviour (hazard), varying number and type of buildings exposed to the lahar (exposure) and the uncertain susceptibility of buildings to lahar impacts (vulnerability). In this paper, we quantify and examine the importance of lahar hazard, exposure and vulnerability in determining building damage with reference to a case study in the city of Arequipa, Peru. Numerical modelling is used to investigate lahar properties that are important in determining the inundation area and forces applied to buildings. Building vulnerability is quantified through the development of critical depth–pressure curves based on the ultimate bending moment of masonry structures. In the case study area, results suggest that building strength plays a minor role in determining overall building losses in comparison to the effects of building exposure and hydraulic characteristics of the lahar.

Citation: Mead, S. R., Magill, C., Lemiale, V., Thouret, J.-C., and Prakash, M.: Examining the impact of lahars on buildings using numerical modelling, Nat. Hazards Earth Syst. Sci., 17, 703-719,, 2017.
Publications Copernicus
Short summary
Volcanic mudflows, called lahars, can cause large amounts of damage to buildings. In this research we developed a method to estimate lahar-induced building damage based on the height, speed and amount of volcanic material in the lahar. This method was applied to a small region in Arequipa, Peru, where computer models were used to estimate the number of buildings affected by lahars. The research found that building location and the size of the flow are most important in determining damage.
Volcanic mudflows, called lahars, can cause large amounts of damage to buildings. In this...