| This paper studied the shear capacity of the anchor bolts in steel column bases.5groups, totally15specimens were tested, in which the anchor bolt diameter, column base plate thickness, bolt hole diameter are varied. The relations of the shear force to the slip on the steel-concrete interface were obtained. All the experimental shear-slip curves are of the similar shape. Each of these curves can be approximately divided into three stages, the elastic, slipping and hardening stages. On the experimental results, the design-oriented shear strength of the studied connections is suggested to take the load corresponding to the end of the elastic stage, and the ultimate shear strength is also proposed, for the consideration of its behaviour under strong earthquake load. It is found that the thickness of the base plate has a great effect on the shear capacity of the anchor bolt connections, while the effects of the difference between the diameters of the bolt hole at the base plate and bolt is not significant. The failure modes of the specimens are tension-shear failure of the anchor bolts and punch-shear failure of the concrete. Large area rust imprints were found in all specimens on the top face of concrete around the anchor bolts, indicating strong compression occurred on the interface between the base plate and concrete in test.Finite element analysis (FEA) was carried out using the general FE code ABAQUS, where the contact behaviours at steel-concrete and bolt-hole interfaces, as well as the nonlinear properties of steel and concrete are considered. Reasonable agreements can be seen between the shear-slip curves from the test and FE analysis.Tension forces were determined in the analysis, and was found to be50%-67%of the shear forces in the elastic-slip range. These tension forces are then used to determine the friction shear resistance to achieve a better correlation between the test and the proposed formula. |
