Blast Design of Reinforced Concrete and Masonry Components Retrofitted with FRP.

Book excerpt: Fiber-reinforced polymer (FRP) products are used as an alternative to traditional methods for strengthening and retrofitting concrete and masonry structures to resist blast loads. The development and experimental validation of a methodology for modeling the response of blast loaded concrete and masonry structural components retrofitted with FRP, as well as corresponding response criteria, is important since these types of components often require upgrades in order to provide personnel protection in blast-loaded buildings. This paper discusses the development of a SDOF-based procedure for designing FRP upgrades to blast loaded masonry and concrete walls by Protection Engineering Consultants for the U.S. Army Corps of Engineers, Protective Design Center. This includes the methodology used to determine the flexural stiffness and ultimate flexural and shear resistance of the upgraded walls. The methodology for estimating the flexural resistance of concrete and masonry components is based on current codes and guidelines (ACI-318 and ACI 440.2R). Experimental data from previous shock tube tests on concrete and masonry walls retrofitted with FRP were used to validate the upgrade design procedure by comparing the observed and calculated response of the tested components. Furthermore, proposed response criteria were developed for flexural and shear response of the walls for damage levels used for DoD antiterrorism design. These damage levels can be correlated to those used in UFC 3-340-02 for explosive safety.