Reliability Analysis of Continuous Beam Using Hasofer-Lind Reliability Method

This project work “Reliability analysis of a continuous beam using Hasofer-Lind Reliability Method” was primarily concerned with the effect of varying parameters such as load, modulus of elasticity, moment of inertia and span length on the reliability of a continuous beam. The limit state considered is deflection, and the allowable deflection is specified as L/360. The maximum deflection is 0.0069wL^4/EI and it occurs at 0.446L from either end (AISC, 1986).

Reliability analysis, expressed in the form of reliability index (β) and probability of failure (Pf) were performed for continuous beam using Hasofer-Lind Reliability Method (simultaneous equation procedure) in MATLAB. 

A program written in MATLAB was used to compute the safety indices for every set of parameters that were varied and Results of the reliability analysis shows that, the safety indices decreases slightly with increase in load within standard deviation and the probability of failure is at the range of 103- 104. Results also shows that the modulus of elasticity has significant effect on the reliability of the continuous beam, as the safety indices increases linearly with increase in modulus of elasticity within standard deviation, the probability of failure increases too. Results also shows that the safety indices decreases linearly with increase in moment of inertia within standard deviation and also the safety indices decreases linearly with increase in span length and the probability of failure is at the range of 103- 104. The research concludes that the continuous beam is safe for variation of parameters like span length, moment of inertia and load while care should be taken in modulus  of elasticity of the structural members.