Stability analisys of modular steel shoring systems

Abstract

Modular steel shoring systems are temporary structures used to support construction loads of high clearance concrete structures. These loads consist of self-weight, fresh concrete, formwork, steel, workers and equipment, etc. Maybe due its temporary characteristic, little importance has been given to the structural analysis and design of these structures. However, the highest risk to structures during their lifetime is generally during the construction phase. This is evidenced by the fact that most structural failures occur during the placement of fresh concrete in construction rather than after the structure is completed and is in service. The immediate consequence of this negligence is a considerable number of construction accidents, causing injuries, loss of life, property damage, financial loss and construction delays. As the modular units are usually fabricated from slender members with flexible connections and are subjected to compressive forces, stability problems are one of the main causes of collapse of these structures during construction. Thus, it is important to evaluate the buckling load of the modular shoring systems (support scaffolds) which depends not only on the geometry and material, but also on the boundary conditions, types of loading and connection between the members of the system. This work discusses the stability analysis of scaffold systems used in the construction of high clearance concrete structures. The systems are analyzed using two-dimensional models to obtain the critical load. The effect of mesh discretization, scaffold geometry, bracing system, and number of modules (layers) is analyzed by numerical examples.