Experimental Case Study Demonstrating Advantages of Performance Specifications

The National Ready Mixed Concrete Association (NRMCA) has an initiative to evolve specifications from prescriptive requirements to performance-based concepts for concrete mixtures. The Prescription to Performance (P2P) Initiative has been identified by concrete producers as an important initiative that will elevate the quality of concrete construction by providing qualified concrete producers the ability to use their expertise to optimize concrete mixtures for intended performance of concrete structures. This project is a laboratory study designed to investigate the advantages of performance-based criteria over prescriptive requirements in concrete specifications. For the study typical specifications for two types of applications and the ACI 318 code provisions have been chosen. These specifications are generally prescriptive in nature. Concrete mixtures were prepared according to the prescriptive provisions of these specifications and compared to mixtures that satisfy intended performance attributes. Fresh and hardened concrete properties were quantified and compared. This comparison demonstrates the benefits and optimization of concrete mixtures from performance based specifications.