Sustainable nHPC Mixtures for Durable Overlay of Concrete Bridge Decks in Cold Regions: Proof of Concept

The higher cement content in UHPC increases the energy and CO₂ footprints, and the use of supplementary cementitious materials (SCMs) to replace cement has been limited in the current design. Besides, the high compressive strength (> 150 MPa) of UHPC might be over-design for bridge deck overlay application. The combined use of very low w/b ratio (~ 0.2) and high dosage of fibers presents a great challenge for the construction of UHPC overlays in the field. In this context, the overarching goal of this project is to design sustainable nHPC mixtures for durable overlay of concrete bridge decks in cold regions through lowering initial cost of UHPC overlays and improving the workability and construction tolerance of UHPC for on-site application while maintaining dense microstructure and superior durability. The “n” before the HPC denotes for nano-engineering as well as the fact the durability of these mixtures will be a few times that of conventional UHPC. To achieve this goal, this study aims to: (1) identify and optimize eco-efficient mix designs for nHPC overlay, greatly reducing the use of cement, steel fiber and superplasticizer while tailoring the particle size gradation; (2) evaluate the engineering performance and durability of selected nHPC mixtures for cold-climate concrete deck overlay application; (3) enhance the thixotropy to ensure that fresh nHPC mix can hold the specified slope on the bridge deck; (4) conduct multiscale characterization of selected nHPC mixtures, to elucidate the role of individual constituents on the macroscopic behavior and performance.

Language

  • English

Project

  • Status: Active
  • Funding: $180856
  • Contract Numbers:

    69A3551947137

  • Sponsor Organizations:

    Transportation Infrastructure Durability & Life Extension

    Washington State University
    Department of Civil & Environmental Engineering
    Pulman, Washington  United States  99163
  • Managing Organizations:

    Transportation Infrastructure Durability & Life Extension

    Washington State University
    Civil & Environmental Engineering
    Pullman, Washington  United States  99164
  • Project Managers:

    Kline, Robin

  • Performing Organizations:

    Washington State University, Pullman

    Civil & Environmental Engineering Department
    PO Box 642910
    Pullman, WA  United States  99164-2910
  • Principal Investigators:

    Shi, Xianming

  • Start Date: 20210501
  • Expected Completion Date: 20220930
  • Actual Completion Date: 20220930
  • USDOT Program: University Transportation Centers
  • Subprogram: Transportation Infrastructure Durability & Life Etension

Subject/Index Terms

Filing Info

  • Accession Number: 01773717
  • Record Type: Research project
  • Source Agency: National Center for Transportation Infrastructure Durability and Life-Extension
  • Contract Numbers: 69A3551947137
  • Files: UTC, RIP
  • Created Date: Jun 3 2021 11:50AM