1 Background 1.1 What is a tack coat? Tack coat – A thin surface treatment of liquid asphalt cement or emulsion applied to enhance bond between a new HMA surface and existing road surface and recommended between each lift of new HMA (Figures 1.1-1 and 1.1-2). The liquid asphalt material is applied to new, milled, or un-milled bituminous or to concrete surfaces being overlain to improve bonding between layers and create the monolithic structure needed to support wheel loads as intended by pavement designers. Pavement layers act as a beam and inadequate bond between lifts can allow excessive bending, strain, or slippage that results in delamination or premature failure.
1 Background 1.1 What is a tack coat? Tack coat – A thin surface treatment of liquid asphalt cement or emulsion applied to enhance bond between a new HMA surface and existing road surface and recommended between each lift of new HMA (Figures 1.1-1 and 1.1-2). The liquid asphalt material is applied to new, milled, or un-milled bituminous or to concrete surfaces being overlain to improve bonding between layers and create the monolithic structure needed to support wheel loads as intended by pavement designers. Pavement layers act as a beam and inadequate bond between lifts can allow excessive bending, strain, or slippage that results in delamination or premature failure.
Tack%20Coat%20RCK%2003232018.docx