Effects of Wet Mat Curing Time and Earlier Loading on Long-Term Durability of Bridge Decks: Compressive Strength, Maturity and Strength Durability Index (SDI)

摘要

There is increasing pressure from owners, contractors, and the public to open bridge decks sooner to full traffic loads. As a result, a set of criteria or guidelines is needed to determine when concrete bridge decks can safely be opened. Today, current practice allows many bridge decks and concrete pavements to be opened to traffic once a desired compressive strength is achieved from a representative field-cast test cylinder. Though generally untrue, many believe that this strength value serves as a measure of the durability of the placed concrete. In a collaborative research effort between Texas Department of Transportation and researchers at Texas Tech University, studies were undertaken to collect research data that could potentially lead to the development of new guidelines as to when bridge decks can be open to (1) construction traffic and (2) full traffic without sacrificing concrete durability. This report presents detailed findings of two research thrusts: compressive strength and maturity curves commonly used on bridge deck concrete mixes and comparative assessment of the effectiveness of three curing methods that led to the development of a framework for a Strength-Durability Index (SDI).