Laser heating: a minimally invasive technique for studying fire-generated heating in building stone

Miguel Gómez-Heras; Rafael Fort; Miguel Morcillo; Carlos Molpeceres; José Luis Ocaña

doi:10.3989/mc.2008.v58.i289-290.82

Authors

Miguel Gómez-Heras School of Geography, Archaeology & Palaeoecology, Queen’s University Belfast
Rafael Fort Instituto de Geología Económica (CSIC-UCM), Madrid
Miguel Morcillo Centro Tecnológico Laser, Universidad Politécnica de Madrid
Carlos Molpeceres Centro Tecnológico Laser, Universidad Politécnica de Madrid
José Luis Ocaña Centro Tecnológico Laser, Universidad Politécnica de Madrid

DOI:

https://doi.org/10.3989/mc.2008.v58.i289-290.82

Keywords:

Deterioro de la piedra, Fuego, Irradiación láser, Técnicas no invasivas

Abstract

Due to the irreparable damage it can cause, fire is one of the major risks to buildings. Recent studies on the effects of fire tend to focus on micro-scale analysis, addressing questions such as micro-cracking or mineralogical or chemical changes that are particularly relevant to listed buildings.
The fire simulation techniques employed to date (convection heating laboratory furnaces and real flame tests) are subject to a series of limitations including non-repeatability, the lack of combustion by-products and, most importantly, the need to work with large samples. In this final context, techniques must be found that require only minimal sample sizes.
This paper introduces laser irradiation as a technique suitable for simulating the “combustion” of building materials, since it mimics the physics of fire, is repeatable, yields combustion products and, most importantly, can be applied to small specimens. Indeed, as laser irradiation concentrates high amounts of energy in small areas, it can be used for micro-scale testing.

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