An Innovative Approach to Enhance Self-Healing in Cementitiously Stabilized Soils and Mitigate Shrinkage Cracking

Although cementitious stabilization offers great advantages, such as beneficial utilization of the in-situ inferior materials or waste/byproducts, it suffers from shrinkage cracking which limit the widespread use of this technology. The proposed study is on an innovative approach that couples self-healing effects of bacterial spores with sequential hydration methodology that could mitigate the development of shrinkage cracking of stabilized mixture while sustaining the development of high strength. Traditionally, there is a tradeoff between high strength and susceptibility to shrinkage cracking which typically happens soon after the construction. High strength is desired from the standpoint of providing support to structure on the stabilized materials. However, high strength of stabilized materials leads to high potential to shrinkage cracking. Traditionally, optimum moisture content of the stabilized material is specified at the time of mixing to reach the strength needed. The mixture with optimum moisture content, however, suffers from shrinkage cracking. Sequential hydration is a concept for which moisture content below optimum is provided for partial hydration. The mixture will develop initial strength, but low shrinkage strain, due to partial hydration and limited moisture to evaporation. The relaxation of stabilized mixture reduces the shrinkage stress of stabilized mixture when it is restrained from free movement. The subsequent supply of moisture will allow for stage-two hydration to develop a high strength. The final shrinkage strain and shrinkage stress is also reduced, due to developed strength and relaxation during partial hydration. In addition, the stage-two hydration will arrest cracks, if any, during initial hydration which is an autonomic self-healing function. The stabilized mixture with sequential hydration has potential to develop high strength and low shrinkage cracking potential. The mixes containing bacterial microcapsules which enhance self-healing is expected to benefit immensely from the sequential hydration and lead to a novel design for cementitious stabilization.

Language

  • English

Project

  • Status: Active
  • Contract Numbers:

    ORSO 135461

  • Sponsor Organizations:

    Transportation Infrastructure Durability & Life Extension

    Washington State University
    Civil & Environmental Engineering
    Pullman, Washington  United States  99164

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • 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:

    Wen, Haifang

  • Start Date: 20200501
  • Expected Completion Date: 20220930
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers

Subject/Index Terms

Filing Info

  • Accession Number: 01754381
  • Record Type: Research project
  • Source Agency: National Center for Transportation Infrastructure Durability and Life-Extension
  • Contract Numbers: ORSO 135461
  • Files: UTC, RIP
  • Created Date: Oct 12 2020 10:40AM