Performance Criteria for Ready Mixed Concrete: Where Are We Today? (Part 1)-Prescription to Performance (Recorded Presentation)

Video Transcription

Video Summary

The talk focuses on Minnesota DOT's transition from traditional prescription to performance concrete mixes. Initially, from pre-2006, mixes were totally prescriptive and resulted in significant bridge deck cracking. By 2006, after observing national trends in bridge deck failures and growing industry interest in high-performance concrete, MnDOT collaborated with the ready-mix industry to develop performance-oriented specifications. This evolution led to a successful performance specification crafted by 2009, aiming to reduce cracking and enhance durability by allowing more flexibility, such as using varied supplementary cementitious materials and setting slump ranges. MnDOT's specifications have continued to evolve, incorporating aspects like lightweight aggregates and macrofibers to further bolster durability and minimize cracking. Overall, these changes significantly improved bridge deck performance across Minnesota, demonstrating the advantages of performance specification over traditional prescriptive methods in concrete mix design.

Keywords

MnDOT

performance concrete

bridge deck cracking

supplementary cementitious materials

macrofibers