Load-carrying capacities and failure modes of scaffold-shoring systems, Part I: Modeling and experiments

This paper proposes a simple numerical model for use in a finite analysis ( FEA) of scaffold-shoring systems. The structural model consists of a single set of multiple-story scaffolds with constraints in the out-of-plane direc tion at every connection joint between stories. Although this model has onl y two dimensions (termed the 2-D model), it is derived from the analysis of a complete scaffold-shoring system and represents the structural behavior of a complete three-dimensional system. Experimental testing of scaffolds u p to three stories in height conducted in the laboratory, along with an out door test of a five-story scaffold system, were used to validate the 2-D mo del. Both failure modes and critical loads were compared. In the comparison of failure modes, the computational results agree very well with the test results. However, in the comparison of critical loads, computational result s were consistently somewhat greater than test results. The decreasing tren ds of critical loads with number of stories in both the test and simulation results were similar. After investigations to explain the differences betw een the computationally and experimentally determined critical loads, it wa s recommended that the 2-D model be used as the numerical model in subseque nt analysis. In addition, the computational critical loads were calibrated and revised in accordance with the experimental critical loads, and the rev ised critical loads were then used as load-carrying capacities for scaffold -shoring systems for any number of stories. Finally, a simple procedure is suggested for determining load-carrying capacities of scaffold-shoring syst ems of heights other than those considered in this study.