Historical knowledge in the preservation of heritagetimber structures

In the analysis and rehabilitation of ancient timber structures, the knowledge on the mechanical properties of wood available at construction time and the dimensioning rules adopted in the period are an important element for understanding the structure in its original conceptual design and its subsequent history. Here, treatises and manuals of the 18th and early 19th century are examined with the aim at investigating the level of information available to designers of timber bridges. Extended and precise experimental campaigns had supplied a good level of information on the characteristics of the material. These data constituted a base also for the development of theoretical aspects and finally for the expression of design formulas.