Effects of geometrical shape and incremental loads on scaffold systems

This paper investigates the influence of geometry-dependent loads and time-dependent incremental loads on the scaffolding systems with different configurations. The loading types considered are the uniform load, geometry-dependent load and incremental load. The geometry-dependent loads include the trapezoidal and triangular loads. Further, the mixed and bare scaffold systems with and without wooden posts at top are considered under the rectangle, L and U configurations on plan. It was found that the mixed scaffold system with wooden posts of typical length 1.7 m at top had a buckling resistance of only half of the bare scaffold system without wooden posts. Also, the largest deformation in the bare scaffold is found to be near the upper joint of the lowest scaffold layer and, in the mixed scaffolding system, the largest deflection occurs at the location between the bottom of the wooden post and top of the highest scaffold layer. Both systems buckle in the in-plane direction of the scaffolds. The critical load of a 3-bay 5-row 3-storey mixed scaffold system is considered under uniform load and its buckling resistance is found to be invariant under geometry-dependent loads and incremental loads. The buckling resistances of increasing the number of bays in the bare and mixed scaffold systems under the uniform load effect are much greater than choosing a particular geometrical L or U configuration. (c) 2006 Elsevier Ltd. All rights reserved.