Monotonic shear strength of headed studs in reinforced infill walls

Abstract

Headed studs are key components of structures which facilitate composite behavior between steel and concrete elements. In steel building structures, reinforced concrete infill walls surrounded by a stiff steel frame is a common example of a composite structure used to resist horizontal loads such as those produced by earthquakes or wind. To this end, these types of concrete walls need to be anchored to the steel frame with headed studs which must withstand shear and tensile forces (AISC 360). To properly design headed stud anchors in concrete walls, it is first necessary to understand their behavior when subjected to monotonic shear forces considering edge conditions and reinforcing details that may influence the stud strength.Few tests have examined headed studs subjected to monotonic shear with typical boundary effects in reinforced infill walls, so a new experimental study on 17 specimens explores the behavior of headed studs exposed to monotonic shear loading with group effects. The experiments showed that the strength of studs installed in infill walls with edge conditions is well predicted (average error in prediction is smaller than 10%) by ACI 318, AISC 360 and EC-4. However, when group effects of anchors are included in the analysis of infill walls, only the ACI 318 is able to predict the behavior.