Crack Width Limit for UHPC Structural Members in Coastal and Marine Environment

Details

• Creators:
  Zhang, Qian ; Riding, Kyle ; Wang, Peizhi ; Zeidan, Randa
• Corporate Creators:
  Florida State University
• Corporate Contributors:
  Florida. Department of Transportation. Research Center ; University of Florida
• Subject/TRT Terms:
  • Ultra high performance concrete
  • Transport properties
  • Corrosion tests
  • Cracking
  • Coasts
  • Durability
  • Sealing
  • Monitoring
  • Chlorides
  • Literature reviews
  More +
• Publication/ Report Number:
  9
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Florida
• Edition:
  May 2021 - Jun. 2026
• Corporate Publisher:
  Florida. Department of Transportation
• Abstract:
  Ultra-high-performance concrete (UHPC) is increasingly used in transportation infrastructure because of its high strength, dense microstructure, low permeability, fiber-bridged crack control, and self-healing potential. These properties make UHPC suitable for structural members exposed to coastal and marine environments, where chloride-induced corrosion of embedded reinforcement is a major durability concern. However, the durability performance of cracked UHPC remains less clearly defined, particularly with respect to chloride ingress, crack geometry, self-healing, and reinforcement corrosion under realistic marine exposure conditions. This report evaluates crack-width limits for UHPC structural members exposed to chloride-rich environments. The study included a literature review, mixture characterization of four UHPC mixtures, chloride migration testing, long-term bulk diffusion testing, laboratory wetting-drying corrosion exposure, and tidal-zone marine exposure at Seahorse Key Island. The results showed that uncracked UHPC provided very high resistance to chloride ingress and maintained passive reinforcement conditions. In cracked UHPC, chloride transport was governed by crack width, crack depth, crack density, crack interaction, and self-healing behavior. Although cracked regions showed higher chloride transport than uncracked UHPC, corrosion activity generally remained low when cracks were tight and adequate cover was provided. Based on the experimental results, crack-width action levels are recommended for UHPC members with cover thickness greater than 25.4 mm (1.0 in.), including routine acceptance for cracks not exceeding 0.20 mm (0.008 in.), monitoring or preventive sealing for cracks from 0.20 to 0.40 mm (0.008 to 0.016 in.), engineering review for cracks from 0.40 to 0.80 mm (0.016 to 0.031 in.), and immediate repair review for cracks greater than 0.80 mm (0.031 in.).
• Format:
  PDF
• Funding:
  BED30 977-05
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/93273/dot_93273_DS1.pdf
• File Type:
  [PDF - 8.47 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:88db107a15896ed5469d736f22169fd494c94ab252f5170460d7e9fe7435152d7a6c38aa60e12686c8a006a9f81d199c30db9b206a7a8ff2ef7c5b1492e6f98c