Reliability‐Based Design of Wood Structural Systems

Abstract

A methodology is presented for the study of the reliability of lightframe wood structural systems, with particular consideration given to floors and flat roofs. Reliability levels associated with the bending strength limit state of such systems are computed by first‐order reliability methods, using a structural analysis based on the finite strip method. A system modification factor is derived in relation to a simple design equation for bending, which is suitable for implementation in a limit states design code. Values for the modification factor are studied in relation to different parameters: plate action of the sheathing, the non‐rigid connection between the sheathing and the joists, the variability in the strength and stiffness of the joists, the applied load variability, the geometric parameters of the floor and the definition of system failure. The system modification factor, when applied to the simple design equation based on a single member, ensures a prescribed reliability for the structural system,