Sunday, February 5, 2012
Fire tests of some New York building stones, 1906
Fire tests of some New York building stones, by Walter Edward McCourt, Published by the New York State Department of Education, 1906,
The recent extensive conflagrations in some of our large cities have made more urgent than ever a demand for definite knowledge of the capacity of various construction stones for resistance to fire. Little has been done in the investigation of refractori-
ness of building stones and it is probable that the occasional recorded tests have been based on series too incomplete and on samples too small for reliable coordination of results.
With the purpose of acquiring some definite information regarding the fire-resisting qualities of certain New York building stones, Prof. Heinrich Ries has, at my request, initiated and superintended the investigation here given, the details of the work having been carried out by Mr W. E. McCourt.
The types of building stones on which the work is based have been selected as representative of those produced in this State
and all have been assembled specially for these investigations. A few examples also have been tested which are not now used for structural purposes.
The work has been done carefully and thoroughly and the result arrived at should prove of value to engineers, architects and fire insurance underwriters.
JOHN M. CLARKE,State Geologist. The first investigator to carry on any series of tests to ascertain the relative capacity of the various building stones to resist the action of extreme heat was Cutting, who performed some experiments for the Weekly Underwriter in order that insurance rates might be more properly adjusted. He estimated the relative rank of different stones in their capacity to withstand the action of extreme heat as, from highest to lowest, marble, limestone, sandstone, granite and conglomerate.
Cutting 1 states:
As to granites ... a heat sufficient to melt lead is sufficient to injure granite walls beyond the capability of repair, otherwise than by taking down, and it is almost, if not quite, impossible to burn out a granite building of small size, even, without injuring the walls.
Sandstones stand fire much better than granite. They stand uninjured a degree of heat that would destroy granite.
i Weekly Underwriter. 1880. 23:42.
Lead Melting point 600.61 K, 327.46 °C, 621.43 °F
It seems, however, to be well proven that of all stones granite is the least fireproof, while the fact that certain of the fine grained silicious sandstones are used for furnace backings would seem to show that if not absolutely fireproof, they are very nearly so.
1904 Rochester N.Y.
1904 Baltimore, Md.