RELIABILITY-BASED OPTIMIZATION OF PLANT PRECAST CONCRETE STRUCTURES

This paper presents a decision model for minimizing the life-cycle cos t of prefabricated concrete elements and structures, taking into accou nt the building design-manufacturing-construction-service life process as a whole. The decision model utilizes principles of engineering eco nomic analysis under uncertainty in considering costs and benefits of construction, maintenance, repair, and consequences of failure. The co ncepts are illustrated for plant precast hollow-core concrete floor sl abs. Decision variables can include parameters related to concrete qua lity, manufacturing process technology, and maintenance. The optimal s olution identifies those values of the decision variables that result in minimum expected total cost. The performance constraints, in the fo rm of limits on the probability of flexural failure, shear failure, cr acking, and excessive deflection are formulated using principles of st ructural reliability theory.