Hessian (also known as burlap) has many uses across many industries, and for the concreting industry is predominantly used for retention of water while curing in-situ or precast concrete. It is sometimes referred to as a curing blanket, and is used because of its good water absorptive properties.
A concrete curing blanket is a cover that helps maintain the temperature and moisture level of newly poured concrete during the curing process. They are also known as insulation blankets, concrete curing tarps, winter blankets, or masonry blankets.