In this project, development of a computational platform is proposed for analyses and whole-system simulations of structural response during extreme events, such as blasts, explosions and high-velocity impact. The platform will be constructed with novel methods developed through research, and with best available technologies for extreme event simulations. The structural response will be obtained at multiple spatial and temporal scales simultaneously, in order to achieve high fidelity and computational efficiency. Three different scales will be considered: (Fine Scale) In the immediate vicinity of the extreme event, response will be simulated using a novel Mesh-free method. Within this zone, the consideration of extremely fine spatial and temporal scales is needed to capture fracture, fragmentation and phase changes of materials under high-strain rates. (Medium Scale) For the structural members adjacent to the fine scale zone, novel Finite Element methods will be utilized to capture failure through cracking, large deformations, and inelastic material behavior. (Coarse Scale) For the rest of the structure, robust and accurate structural (beam, plate) finite elements will be used to obtain the global response. These three types of zones will be interfaced with novel methods that will enable the use of non-matching temporal and spatial discretizations (i.e., different time-step sizes, finite elements and mesh-free nodes) within each zone. Through this methodology, it will be possible to obtain local (member and material failure) and global (structural collapse) responses with a high accuracy and computational efficiency. The proposed platform will also be capable of performing recursive and adaptive computations to enhance computational efficiency. The proposed computational platform will be capable of considering the global and local response of structures during extreme events. This approach is necessary to determine the failure of members that are directly exposed to the extreme events and the progressive collapse mechanisms of the structure as a whole. Currently there is no such simulation tool in existence. As such, the proposed platform will aid forensic engineers in vulnerability assessment studies, and in the development of blast/impact-resistant design and retrofitting techniques. The research outcomes will have a broad impact on related fields. The element formulations, analysis methods and algorithms generated throughout the project will be applicable to earthquake engineering, material response modeling, fracture mechanics, and structural dynamics fields in general. Through the outreach activities, the project will generate a viable synergy between researchers in academia, in national research laboratories, and forensic engineers. The graduate students will be trained through research, internships, and participation in outreach.
