Concrete Sidewalk Investigation

Over the past few years, the District of Columbia Department of Transportation (DDOT) has been using Class F concrete to construct the city's sidewalks, aprons, curbs, and gutters. Through proper mix design control, monitoring of concrete placement, sampling and testing, DDOT's experience with Class F has been acceptable. However, recent reports indicate that there are problems with this mix in some areas of the city. The concrete that has shown deterioration and distress the most are those on sidewalk constructed between 2005 and 2010 in various sections of the city. Through one winter season the concrete exhibited extensive scaling, spalling, and limited cracking. A number of factors can affect the performance and durability of sidewalk concrete. The effect of some factors can be evaluated by reviewing the project documents. Examining concrete tickets, and reviewing inspection and testing records are some of the reviews that can be undertaken. Other major contributing factors, such as hardened characteristics of concrete, contractor construction practice and finishing procedures, as well as the impact of de-icing chemicals and salt, need detailed studies or evaluations. The implementation of this study will be based on the findings of both the in-house record search and evaluation, and the results of the concrete petrographic analysis. If the results show that there was proper control on the concrete placement and finishing, and the petrographic analysis indicates that it is consistent with the properties of the class F mix, then the mix design should be further evaluated. If the results show otherwise, the class F mix will remain as is and may need better supervision of contractor's work, including subgrade and base preparation, concrete placement and finishing practice.

    Language

    • English

    Project

    • Status: Terminated
    • Funding: $30000.00
    • Sponsor Organizations:

      District of Columbia Department of Transportation

      55 M Street, SE
      Washington, DC  United States  20003
    • Project Managers:

      Khan, Wasi

      Medhani, Rezene

    • Performing Organizations:

      District of Columbia Department of Transportation

      55 M Street, SE
      Washington, DC  United States  20003
    • Principal Investigators:

      Khan, Wasi

      Medhani, Rezene

    • Start Date: 20121001
    • Expected Completion Date: 0
    • Actual Completion Date: 0
    • Source Data: RiP Project 32352

    Subject/Index Terms

    Filing Info

    • Accession Number: 01473444
    • Record Type: Research project
    • Source Agency: District of Columbia Department of Transportation
    • Files: RiP, STATEDOT
    • Created Date: Feb 22 2013 1:00AM