• Journal of Korean Society of Steel Construction
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• v.22 no.2
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• pp.121-128
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• 2010

The current trends in steel construction involve the use of tapered sections to minimize the use of excess materials to the extent possible, by choosing cross-sections that are as economical as possible abandoning the classical approach of using prismatic members. In addition, snug-tightened connections, especially the end-plate type, have the advantage of fetching less construction costs and shorter assembly times as opposed to fully tightened joints. Although they have many merits, however, snug-tightened bolted end plates are extremely complex in their structural behavior. In this study, an experimental investigation of the snug-tightened flush end-plate connections of tapered beams were conducted. The primary test parameters were the torque for the clamping bolt, the loading pattern, the bolt type and the connection failure type. Using initial stiffness and load-carrying capacity as proposed by Silva et al. and AISC (2003), the moment-rotation curve of a linearly tapered member with a snug-tightened flush end-plate connection was predicted. Moreover, numerical and experimental data for moment-rotation curves were compared.

• Journal of Korean Society of Steel Construction
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• v.24 no.3
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• pp.257-265
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• 2012

Current trends in steel construction include using tapered, non-compact sections to minimize the use of excess material as much as possible by choosing the cross-sections instead of the classical approach of using prismatic members. In addition, snug conditions, especially the end-plate type, have the advantage of incurring less construction costs and shorter assembly times as opposed to full pre-tensioned conditions. On the other hand, it is important to predict the collapse of the PEB system due to over-loading. Large-scale tests of tapered steel portal frames with non-compact sections were conducted. The primary test parameters included the bolt connection method and the loading condition (vertical and horizontal load). The test results on initial stiffness and load capacity were investigated. Furthermore, comparisons between the analytical and experimental data for load-displacement curves were initiated. In addition, we evaluated the applicability of a snug bolt for the PEB frame in the field.

• Steel and Composite Structures
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• v.48 no.5
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• pp.547-564
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• 2023

This study investigates the effect of bolt preloading on the rotational stiffness of stainless steel end-plate connections. An experimental programme incorporating 11 full-scale joint specimens are carried out comparing the behaviours of fully pre-tensioned (PT) and snug-tightened (ST) flush/extended end-plate connections, made of austenitic or lean duplex stainless steels. It is observed from the tests that the presence of bolt preloading leads to a significant increase in the rotational stiffness. A parallel finite element analysis (FEA) validated against the test results demonstrates that the geometric imperfection of end-plate has a strong influence on the moment-rotation response of preloaded end-plate connections, which is crucial to explain the observed "two-stage" behaviour of these connections. Based on the data obtained from the tests and FE parametric study, the performance of the Eurocode 3 predictive model is evaluated, which exhibits a significant deviation in predicting the rotational stiffness of stainless steel end-plate connections. A modified bi-linear model, which incorporates three key properties, is therefore proposed to enable a better prediction. Finally, the effect of bolt preloading is demonstrated at the system (structure) level considering the serviceability of semi-continuous stainless steel beams with end-plate connections.