Reliability- Based Failure Verification of Angala Timber Column

This paper carried out reliability-based failure verification of a solid square simply supported Angala timber column in axial compression, bending and combined axial compression and bending respectively to Eurocode 5 (EC5). The limit state function in axial compression, bending and combined axial compression and bending were developed in accordance with the design provisions of EC5. The limit state function in axial compression was developed considering buckling failure of the column in axial compression. The parameters of the limit state functions were considered as random variables with their type of probability distribution obtained from literature. The First Order Reliability Method coded in MATLAB language was invoked in the reliability estimate. It was found that reliability of the column decreased with increase in load ratio, decreased with increase in column slenderness ratio and increased with increase in column dimension considering failure in axial compression, bending and combined axial compression and bending respectively. The design was found to be conservative in bending but satisfactory in axial compression and combined axial compression and bending respectively when compared with the target safety index value of 3.8 for 50-year reference period at ultimate limit state. The computer program developed is easy to run and interactive and it therefore suitable for structural safety estimation.