Structural Design And Analysis Of Transportable,Rapid-assembly Performance Staging

Abstract

The use of structural scaffolding systems is widespread in the concert performance industry. Each year, new stage design concepts are utilized; these new concepts expand the envelope in both physical size (containing over 20,000 members) and load bearing characteristics. A stage design must be quickly assembled, while having the ability to be transportable. The desire to cut costs causes the stage designers to optimize the numbers of structural members which is used in the skeleton of the assembly. In order to determine the structural integrity of the stage design, in depth analysis is required. There is, however, a lack of complex structural analysis performed on the stage designs. Due to the large numbers of people who attend the events, and the injury potential, city inspectors and engineers are becoming very aggressive in their inspection and structural validation of the staging designs. As a result of this scrutiny, one class of concert stage design has been analyzed. The analyzed stage design incorporates a roof truss with dimensions 60 ft. by 48 ft. (18.3 m x 14.6 m); the total material weight of the roof structure is approximately 9000 Ib. (40 KN). Under nominal operating conditions, a dead load of 33,600 Ib. (149.5 KN) is supported by the roof truss. The sound wings, located on each side of the stage, must not only support the roof and lighting systems, but the wings must also support the sound equipment which has a weight of approximately 10,000 Ib. (44.5 KN). The roof grid is supported about 50 ft. (15.25 m) above the stage, by six steel cables which are hung from the sound wings. The analysis which is presented covers both dead and live loads which affect the stage. The analysis looks into the stresses placed upon the various connection schemes which are employed. As a result of this work, a complete design and analysis package is available to the staging manufacturer, validating the integrity of this class of performance staging.