Testing the mechanical resistance of timber used for construction in the marine environment

Abstract

The paper describes refinements of rapid laboratory assessment of the mechanical performance of timbers used in the marine environment as regards their resistance to indentation, impact abrasion from smooth and sharp abrasives and to dynamic impact loads when wet. Ten tropical and home-grown hardwoods, five softwoods and a wood–polymer compound were examined. Brinell hardness, dynamic hardness, abrasion resistance, and the structural integrity in high-energy multiple impact tests were determined comparatively on dry and wet specimens. A trend was shown where softwoods show a decrease in abrasion resistance with wetting, whilst hardwoods did not. In dry conditions, impact abrasion using steel balls was higher than when using sharp grit. It is suggested that when wet, water in the cells has a hydraulic energy absorbing effect.

Keywords

Abrasion resistance Coastal defence Dynamic hardness Groyne High-energy multiple impact test Structural integrity

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