Development of Simplified Tools to Predict Blast Response of Steel Beam-Column Connections

Blast effects testing and analytic modeling of the components of steel frame systems have provided data revealing that steel frame systems, while likely to behave ductility in general, have localized nonductile response mechanisms that actually dictate whether the system as a whole will perform well in a blast environment. Evidence from recent blast effects tests indicates the sections themselves perform well for car bomb type loadings under both weak and strong axis loads. In addition, analytic models indicate close agreement with test results.

However, a troubling aspect of these studies is defining criteria (e.g., fracture strain) that can be correlated with the occurrence of the fractures in sections or connections. These criteria are to be used in analytic models to predict blast effect responses. The ability to predict section and connection fractures/failures and their dependence on strain rate, stress state, or other material and response related factors will ultimately dictate the adequacy of the high-fidelity physics-based (HFPB) models used to simulate blast effects behaviors for steel components and framing systems.

This paper explores analytically various implications of the results of blast effects tests as they pertain to the resilience of steel frame systems. The paper will discuss the development of simplified models for predicting the response of steel beam-column connections to blast loads, using LS-DYNA [1] continuum models.