A major project objective is the development of performance-based design tools, with reliability constraints. The implementation of performance-based design requires a definition of performance, a structural analysis to calculate the relevant performance variables, and an estimation of the reliability with which the performance standard will be satisfied. The problem is generally controlled by a set of random variables plus design parameters. In design, these parameters must be calculated to achieve the reliability levels sought for each performance standard. 

Research in the Civil Engineering Department has focused on the development of software for the estimation of reliability, given information on the intervening variables and design parameters, as well as the inverse problem of calculating those parameters for prescribed target reliabilities. Two general packages, RELAN and IRELAN, have been developed towards these ends. 

Under this project, both RELAN and IRELAN have been adapted using a response surface methodology. Once the response surface for a given performance criterion is developed through deterministic structural analyses, fast and efficient  Windows-based design packages  are developed using the general reliability software. The result is an efficient tool for the development of engineered wood products and also for the general design office. EQFRAME is an example of how RELAN and IRELAN can be implemented for the design of frames. EQFRAME is shown in an example where a dowel connection has to be designed to satisfy three criteria under earthquake loading, with prescribed target reliabilities. The output from EQFRAME are the design parameters chosen for this case: the radius of the dowel arrangement, the diameter of the individual dowels, and their yield strength.