Abstract
Bolted connections are fundamental components of structural steelwork, yet their design is often compromised by secondary effects such as prying forces and localized internal forces that increase bolt tension beyond the nominal value. externally applied loads. These forces arise due to the deformation of connected elements, particularly thin flanges or end plates, and can significantly. influence the load-carrying capacity of a joint. Despite their structural relevance, prying forces are treated with varying degrees of precision across. International design standards lead to inconsistency in predictions and potential. underestimation in engineering practice. This study investigates prying forces. using an approach where a critical examination of international design standards, namely Eurocode 3, AISC (American Standard), SANS 10162 (South African Standard), IS 800 (Indian Standard), and the Australian Standard are compared to detailed finite element analysis (FEA) simulations conducted in Abaqus.
The research simulates T-stub connections under tensile loading.to emulate typical prying prone configurations. Material nonlinearity, contact behaviour, and geometric imperfections were incorporated into the models using solid C3D8R elements. Three T-stub configurations with varying section properties were analyzed to observe the evolution of prying forces across different stiffnesses. and geometry profiles. Results from Abaqus demonstrated clear nonlinear behaviour in bolt force development, with prying forces initiating at the onset of plasticity in the connected plate and evolving as the load increased. The finite element results captured strain hardening, stress redistribution, and localized yielding. phenomena that are largely unaccounted for in simplified analytical models.
Comparative. analysis revealed that while Eurocode provides an upper-bound estimate based on full. plasticity assumptions, it lacks the ability to predict variations in prying force across different load stages. The AISC method, though. straightforward, underestimates the extent of prying due to its reliance on conservative empirical relationships. and assumptions of sufficient flange thickness. The IS 800 model was found to be overly sensitive to parameters like baseplate thickness, which are not central to the configurations. studied. The SANS 10162 approach, which deems prying force acceptable if it remains below 30% of the applied force, was supported by the FEA results. Generally, the study confirmed. that increasing flange or. section thickness mitigates the development of prying forces, thereby improving connection performance...