Developing a spring-based shear connector finite element model for probabilistic analysis of composite beams with deconstructable connectors under connection and material uncertainties

Abstract

Composite beams consisting of precast concrete slabs and steel beams connected by deconstructable high-strength friction-grip bolts (HSFGB) have recently attracted much research attention due to their compatibility with sustainable construction. However, studies on the behavior of these composite beams have been entirely deterministic, with no consideration for uncertainty in the governing parameters, especially for the bolted shear connector varieties. In this paper, a three-dimensional finite element model is developed to investigate the behavior of this type composite beam considering the nonlinearities of the geometry, materials, and component interfaces. Nonlinear springs with zero length are utilized to model the HSFGB shear connectors, and then the complete beam model is embedded in a Monte Carlo-based probabilistic assessment approach. The results show that the simplified spring model is reliable in predicting the behavior of composite beams while being efficient in terms of computational efficiency and time savings for conducting probabilistic analyses. The probabilistic analysis finds that Monte Carlo simulation is a useful method for identifying probabilistic trend behaviors with acceptable accuracy to quantify the effect of structural parameter uncertainties. The composite beam with a partial shear connection shows a greater variety of beam responses than the composite beam with a full shear connection. © 2025 Institution of Structural Engineers