Mechanical performance of elliptical one-sided joints: Loading direction and bolt row effects

Abstract

This paper presents experimental and numerical investigations of shear performance of one-sided single and multi-row bolted joints. This new type of one-sided bolts achieves one-side installation through elliptical bolt head as well as elliptical bolt hole with varying radius along the perimeter on connected members. Because of such configurations, loading angle may affect the joint shear behaviour and therefore sixteen specimens with single one-sided bolt (SBJs) of different diameters are prepared and tested under static shear. Eighteen multi-row bolted joints (MBJs) are also examined to understand the load distribution for this one-sided bolt group in rows with a comparative study to the corresponding ordinary bolt group. Detailed Finite Element (FE) models were developed featuring contact behaviours and bolt pre-tensioning. Comparisons are made between experimental and FE results in terms of load-displacement behaviours and local strain responses. It was found that change of the loading angles posed limited effect on yield capacities of the SBJs; while the joint initial stiffness decreased 38% when the loading angle changed from 0 to 90 degrees. The difference on load transfer factors between one-sided bolted joints (MBJ-O) and corresponding ordinary bolted joints (MBJ-N) is within 14%, where the load transfer factors for MBJ-O were closer to the average.