Toward a quantitative evaluation of timber strength through on-site tests

摘要

Aiming at the structural health evaluation of building materials in historical constructions, it is necessary to identify investigation techniques that gather the desired mechanical data. In this paper, ultrasonic wave propagation (US) and Helifix fastener extraction (HF) are discussed with reference to two softwood species (spruce and pine) and three hardwood species (lime, beech, oak). Young's modulus and bending tensile strength derived by NDT investigations are then compared with values provided by four point bending tests (4PBT). Since a good match is found among the NDT derived mechanical parameters and those directly measured, the proposed procedures can help in estimating the reference grade for existing timber structures.