Evaluation of Natural durability of Horn beam (Carpinus betulus) wood against Coriolus Versicolor in case of Treated with CCA (Tanalith c)

Abstract

In this study, the influence of the fungus (Coriolus versicolor) on the durability of Horn beam (carpinus betulus) in natural state and treated with CCA (Copper/Chromium/Arsenic) was evaluated. CCA is a kind of water borne preservatives that was used to treat specimens under vacuum and pressure (Bethel procedure) with amount of 3.5 & 1.5 percent on the basis of oven dry wood. Specimens were contaminated with cultured fungus for eight weeks in incubator. After this period, weight reduction, compressive strength (parallel to grain) and hardness of specimens were measured. Weight reduction of treated samples with 3.5 & 1.5 percent CCA were 1.68 and 1.73 percent respectively. Weight reduction of control samples were much higher (22.87 percent) than treated ones. There was no significant difference between the Compressive strength (parallel to grain) of treated and control samples without effect of fungus but the samples with effect of fungus have significant difference. Compressive strength (parallel to grain) of treated samples with 3.5 & 1.5 percent of CCA were 64.33 and 60.10 (Mpa) respectively but Compressive strength (parallel to grain) of control samples were much lower (38.44 Mpa) than treated samples. There was no significant difference between the hardness of treated and control samples without effect of fungus. On the other hand, the hardness of treated samples was more than control samples slightly, but this difference was not significant in 5 percent level. The hardness of treated and control samples with effect of fungus have significant difference. Hardness of treated samples with 3.5 & 1.5 percent of CCA were 5788(N) and 5799(N) respectively. However the hardness of control samples were much lower (3139N) than treated samples. Eventually CCA (Tanalith c) increased the durability of Horn beam (Carpinus betulus) from nondurable level to durable level.