Abstract
The objective of this study is to develop a dynamic finite element code that can effectively cope with strong nonlinearities and discontinuities common in impact collapse problems, and whose calculation cost is sufficiently low to enable dynamic analyses of full-model large-scale structures. The Adaptively Shifted Integration (ASI) technique is modified into the ASI-Gauss technique to further reduce calculation cost. Algorithms considering member fractures and elemental contact are also presented. Impact collapse analysis is conducted to simulate the aircraft impact with the World Trade Center South Tower (WTC2), and the analytical results showed good agreement with the observed data.