Cement-polymer prepreg carbon fabrics in concrete strengthening

Fiber reinforced polymers (FRP) have been successfully used in rehabilitation of aged concrete structures, but still little research have been undertaken to develop compatible, durable and cost-saving technologies for structural conservation of monumental buildings. A preliminary study on the use of fiber reinforced cement-polymer matrix composites using prepreg technology is here presented. An experimental program has been therefore developed to define a new waterborne polymer-added cement matrix in order to cast pre-impregnated carbon fiber fabrics. Several variables, including different types of water-redispersible polymers, polymer/cement content ratios and application procedures have been investigated to obtain pre-impregnated fiber mat to be used on site. The impregnated textiles were therefore applied onto standard prismatic mortar samples, by a cement-polymer based grout by hand lay-up technique and subjected to three-point bending tests after room temperature and relative humidity (R. H.) curing. The results, compared to those obtained applying a reference epoxy-based system, exhibited promising applicability and mechanical properties.