Interim report on the investigation of the fresh properties of synthetic fiber-reinforced concrete for the Richardson Landing casting field

Abstract

Abstract : The U.S. Army Engineer District, Memphis, uses the Richardson Landing mat casting field to produce articulated concrete mats that are tied together to form articulated concrete revetment blankets that are then placed on the riverbanks to serve as a form of erosion control. The Memphis District noted that the corners of some of these concrete mats were becoming damaged as the mats were moved from the casting field to the construction site. To combat this issue, the Memphis District, Construction Branch decided to incorporate synthetic fibers in the current concrete mixture proportion to bridge cracks induced by moving the concrete mats. However, there was concern that the addition of fibers would significantly reduce the workability of the concrete mixture, making it labor intensive to place in the forms and difficult to discharge the fresh concrete from transport vehicles at the casting field. The Memphis District contracted with the U. S. Army Engineer Research and Development Centers (ERDCs) Concrete and Materials Branch (CMB) to proportion three fiber-reinforced concrete mixtures containing 3-, 2-, and 1-lb/yd3, respectively, of synthetic (polypropylene) fiber into the current mixture proportion used at Richardson Landing mat casting field. The CMB performed aggregate testing, concrete trial batching, and hardened concrete strength testing to produce the new concrete mixture proportions. This interim report presents the results of testing conducted by the CMB as of 30 August 2016.