Title: Parametric Study on Dynamic Behavior of Post-Tensioned Beams Using Nonlinear Finite Element Modeling

Author(s): Andrew Nghiem and Thomas H.-K. Kang

Publication: Structural Journal

Volume: 119

Issue: 4

Appears on pages(s): 157-170

Keywords: drop-weight testing; dynamic response; failure mechanism; impact tests; nonlinear finite element dynamic analysis (NLFEDA); parametric study; unbonded post-tensioning

DOI: 10.14359/51734658

Date: 7/1/2022

Abstract:
A parametric study was performed to understand the behavior of unbonded post-tensioned concrete beams under low-velocity drop-weight impact. Nonlinear finite element dynamic analysis was used for the simulation of both shear- and flexural-critical members. The modeled design parameters incorporated various concrete strengths, spacing of transverse reinforcement, and increasing levels of post-tensioning force. All beams were simulated under impact at four levels of impacting velocity of the drop hammer. Results of the parametric study were used to identify critical design and loading conditions on the dynamic behavior of unbonded post-tensioned members. Post-tensioning was shown to be beneficial for both shear and flexural resistance against low-velocity impact, and a static shear-to-flexural capacity ratio of at least 5 was found to prevent large shear failure. Additionally, the study was useful at correlating prior experimental results on the behavior of unbonded post-tensioned members, as well as developing the relationship between the peak deformation and the impacting energy and static design capacity with conservativeness.