Experimental studies of ringlock scaffolding joint

Abstract

Experimental studies were performed on ringlock scaffolding joints. The most characteristic element of these joints is a rosette, which provides a temporary connection between the vertical standard and the ledger. Laboratory tests were performed using a typical testing machine and a grip handle developed by the authors, which allows loading the ringlock scaffolding joint with any type of load, regardless of the manufacturer of the scaffolding considered and the material used. A normal force, a shear force in horizontal plane, a shear force in vertical plane, a bending moment in vertical plane, a bending moment in horizontal plane, and torque were applied to the joint. The obtained data could be used to determine the load-bearing capacity of the joint, as well as the nature of the connection. In cases of bending in horizontal plane and torque, the joint should be treated as a hinge, whereas the connection is semi-rigid in case of bending in vertical plane. Four different approaches were employed for determining the joint stiffness. By analysing various modes of joint damage, critical elements could be identified, which could then be used as comparative data when analysing damages to actual structures. Additionally, laboratory tests investigating the material characteristics of individual joint elements were performed. Each joint element had different material characteristics, particularly the ledger end because it was manufactured via moulding.