Repair Strategies for Waste Transfer Station Concrete Overlay

Investigator: North Carolina State University

Start Date:
Mar 2020

Award Amount:
$195,000

Recently, it has been shown that the premature deterioration of concrete overlays in waste transfer stations is a result of simultaneous exposure to leachate (organic acids) and mechanical abrasion by waste handling equipment. In our previous research, we developed a material design guide and specification that owners can use for design or bidding. There are however, important limitations to the  developed guide in that it: (1) does not address repair strategies and repair material selection, (2) is limited to portland cement concrete, (3) does not cover the use of unconventional concretes such as iron aggregate and epoxy matrix, (4) applies to slabs with a minimum of 6-inch thickness and does not cover thin precast and prestressed overlays, and (5) does not include provisions for the use chemical or mineral admixtures that can increase the acid resistance of concrete. The industry is in need of low cost and effective repair strategies for existing concrete overlays.

The goal of the proposed research is to develop a guideline for repair strategies and repair material selection that can be:

  1. Used by owners and operators of waste transfer stations
  2. Adopted and implemented by contractors without the need for specialized equipment and labor.