Abstract
There is the need to subject some Nigerian timber species to reliability analysis in order to establish their structural usefulness. It is on this basis that the Nigerian grown Abura timber was studied and structurally assessed to understand its performance as timber bridge beams. This was achieved by preparing some test specimens of it from naturally seasoned samples at moisture content of 18%.and determining its strength properties, which were subjected to statistical analysis to obtain the mean, standard deviation as well as the coefficient of variation. Structural analysis, deterministic design and structural reliability analysis were performed on the Abura timber bridge beam at the Ultimate Limit State of loading. A computer programme developed in FORTRAN language and First-Order Reliability Method (FORM) were used in the reliability analysis. In order to study the effect of geometry and loading on the reliability index, sensitivity analysis was performed by altering the geometrical dimensions of the beam as well as the magnitude of the loadings on the beam. Satisfactory level of reliability indices were recorded at depth of 400 mm, breadth of 150 mm and span of 5000 mm under the ultimate limit state of loading. The Abura bridge beam depicted very low level of safety when subjected to only shearing forces under the specified design conditions. The probabilities of failure of the Abura bridge beam in compression and shear are 0.68 × 10−5 and 0.023 respectively, under the specified design conditions.
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Aguwa, J.I. Structural performance of the Nigerian grown Abura timber bridge beam subjected to compression and shearing forces. KSCE J Civ Eng 19, 974–981 (2015). https://doi.org/10.1007/s12205-013-0164-9
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DOI: https://doi.org/10.1007/s12205-013-0164-9