Strength and Physical Properties of Zambian Grown Eucalyptus Poles

Abstract

Poles used for overhead power and telecommunication lines and buildings are specified by species, physical properties such as moisture content, and dimensions as well as strength properties such as ultimate load. These properties vary from species to species. Design stresses may be determined using testing methods specified in various codes to arrive at grade stresses. For example, in Australia and New Zealand, the poles are assigned one stress grade higher than the highest grade of the same sawn timber. Design stresses jar American preservative-treated round poles were established following tests specified by ASTM Standards D3200. In the United Kingdom, BS 1990 Parts 1 and 2 give specifications for wood poles for overhead power and telecommunication lines. In Zambia, there is no standard that deals specifically with overhead power and telecommunication lines. However, it is necessary to test Zambian plantation-grown poles and establish basic physical and structural properties. This paper aims to present a method that can be used for for establishing a Zambian standard for poles. Eucalyptus poles are used in fencing, overhead power and telecommunication lines, mine props, support structures, building structures and in the production of sawn timber. In all these uses, the physical and strength properties of the poles are of great importance. This paper presents test results on Eucalyptus grandis and Eucalyptus cloesiana poles which were tested following guidelines for testing poles used for overhead power and telecommunication lines are contained in BS 1990 Part 1. Keywords: Poles; Eucalyptus; Structural properties; Testing