Effects of Compression Creep Deformation on the Microstructure of Terminalia Ivorensis (Black Afara) Timber

Stephen Pinder Ejeh, Yusuf Dada Amartey, Amana Ocholi

Abstract


The effects of compression creep on Terminalia ivorensis timber was presented in this paper. One-year creep test was performed in the laboratory on Terminalia ivorensis timber samples. The creep data were fitted to linear, exponential and logarithmic regression models. The coefficients of determination for each of the model was determined. The coefficients of determination of the linear, exponential and logarithmic models were determined as 0.689, 0.650 and 0.941 respectively.  Since the logarithmic model has the highest correlation with coefficient of determination of 0.941, it gave the best compression creep prediction model for the Terminalia ivorensis timber. Microstructure analysis was conducted on the Terminalia ivorensis timber specie using scanning electron microscope on the specimen. The analysis was conducted before and after creep deformation. The microstructure analysis revealed that, the cellular structure which contained empty vessels was found to have closed after creep deformation. This implied that, the application of the long-term loading lead to the closure of the empty vessels within the cell’s microstructure, leading to the densification of the timber

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