- Author
-
Schroeder, R. A.
- Title
- Post-Fire Analysis of Construction Materials.
- Coporate
- California Univ., Berkeley
- Report
-
THESIS
Fall 1999
277 p.
- Keywords
-
construction materials
|
fire damage
|
wood
|
concretes
|
wallboard
|
gypsum board
|
time
|
heat flux
|
fire investigations
|
physical properties
- Abstract
- The objective of this thesis is to determine and document the extent to which the fire damage in wood, concrete, and gypsum wallboard can be used to determine the time and heat flux exposure of the incipient stages of an uncontrolled fire event. A literature re\:iew outlines the state-of-the-art in three distinct areas: 1. Fire investigation; 2. The physical properties of wood, concrete, and gypsum wallboard, and 3. The fire response characteristics of those materials and their use in fire investigations. The results from quantitative experimental fire exposures of the subject materials are presented. The experiments were conducted under controlled conditions with the intent to develop standards for macroscopic and microscopic states of the materials for a given heat flux exposure and temperature. Standards and procedures are introduced for field sample collection, laboratory testing of the field samples, and interpretation of results. There are three major conclusions to be derived from this dissertation. The first two are that (1) wood and (2) concrete should not be viewed as reliable sources of information for a fire investigator to use for an analysis of how an actual fire ignited or information for a fire investigator to use for an analysis of how an actual fire ignited or spread. On the other hand the third major conclusion is that (3) gypsum wallboard can be considered a reliable source of information of fire behavior. The basis of each these conclusions is described in each of the chapters associated with each of the materials. One of the most important findings in this research is the use of X-ray diffraction to determine the maximum temperature reached by a sample of gypsum wallboard. Then by using the plots of isotherm progression it is possible to estimate the approximate length of esposure to a siven heat flux. The use of gypsum-based post evidence is much more accurate than any available for wood or for concrete.