A great starting point.
But included in this document are some sobering assessments:
Some of which:
"• The sources of much of the data are not identified, and little information is given on the underlying
experimental conditions. As a consequence data merging is an uncertain process because it is often
impossible to ensure compatibility between different entries.
• It is suspected that much of the agreement that does exist between the different data-sets can be
attributed to a high degree of historical ‘borrowing’ one from the other. This in turn may lead, erroneously,
to an optimistic assessment of the inherent uncertainty.
• Many values are quoted without any statement as to whether they correspond to single or multiple
measurements. A random inspection of several referenced works would suggest that values are usually
derived from the work of a single researcher on the basis of a small sample size.
• Many of the data values are derived from work carried out with non-standard apparatus and from a
date which precedes modern standards of equipment and operation.
• No guidance is given on the variation in properties such as density and internal structure inherent in
the production of many building materials."
