Title: Low-Cracking High-Performance Concrete (LC-HPC) for Durable Bridge Decks

Author(s): David Darwin, Rouzbeh Khajehdehi, Muzai Feng, James Lafikes, Eman Ibrahim, Matthew O’Reilly

Publication: Symposium Paper

Volume: 336

Issue:

Appears on pages(s): 101-116

Keywords: bridge decks, consolidation, cracking, curing, finishing, high-performance concrete, temperature control

DOI: 10.14359/51722459

Date: 12/11/2019

Abstract:
The goal of this study was to implement cost-effective techniques for improving bridge deck service life through the reduction of cracking. Work was performed both in the laboratory and in the field, resulting in the creation of Low-Cracking High-Performance Concrete (LC-HPC) specifications that minimize cracking through the use of low slump, low paste content, moderate compressive strength, concrete temperature control, good consolidation, minimum finishing, and extended curing. This paper documents the performance of 17 decks constructed with LC-HPC specifications and 13 matching control bridge decks based on crack surveys. The LCHPC bridge decks exhibit less cracking than the matching control decks in the vast majority of cases. Only two LCHPC bridge decks have higher overall crack densities than their control decks, which are the two best performing control decks in the program, and the differences are small. The majority of the cracks are transverse and run parallel to the top layer of the deck reinforcement. The results of this study demonstrate the positive effects of reduced cement paste contents, concrete temperature control, limitations on or de-emphasis of maximum concrete compressive strength, limitations on maximum slump, the use of good consolidation, minimizing finishing operations, and application of curing shortly after finishing and for an extended time on minimizing cracking in bridge decks.