Ahmed Khalil, P.E, Ph.D from ASI and Tarek Kewaisy, P.E., Ph.D. from Louis Berger will be co-presenting a paper titled “Advanced Modeling of Blast Response of Reinforced Concrete Slabs with and without FRP Retrofit” on March 26 2018 at ACI Concrete Convention and Exposition in Salt Lake City, Utah. The presented research investigated the effectiveness of Fiber Reinforced Polymers (FRP) retrofit technique to improve the blast resistance of RC walls. The primary approach used an innovative numerical simulation technique to model the nonlinear behavior of reinforced concrete when subjected to high levels of blast loading. The simulation technique utilizes the Applied Element Method (AEM) implemented in the Extreme Loading for Structures software (ELS) to predict the dynamic responses and damage patterns due to blast effects. Two concrete and reinforcing bars types; normal and high strength; were considered and both unretrofitted and FRP-retrofitted wall configurations were evaluated. To validate and calibrate the simulation models, experimental blast response measurements for one-way RC slabs were obtained from a testing program sponsored by the NSF, managed by ACI-447 and UMKC/ SCE and completed at ERDC’s Blast Loading Simulator (BLS) at Vicksburg, MS.
Maximum and residual displacement responses and cracking patterns obtained from ELS models were compared to corresponding test measurements. In general the adoption of computationally efficient AEM was found to provide blast performance predictions that are in good agreement with test measurements while having adequate accuracy for practical design applications. It was concluded that the incorporation of FRP retrofit has effectively reduced the blast responses of RC walls by limiting the level and extents of induced structural damage. This technique can be used to design FRP retrofit schemes as a cost-effective option to enhance the blast resistance of RC structures