Live load design moments for parking garage slabs considering support deflection effect

This paper develops a simplified, but effective, algorithm to obtain critic al design moments for clamped and/or elastically supported parking garage s labs. Maintaining the uniformly distributed load concept generally adopted in the design of building structures, this paper introduces the equivalent vehicle load factors which can simulate the vehicle load effects without co nducting additional sophisticated numerical analyses. After choosing a stan dard design vehicle of 2.4 ton following the investigation of small to medi um vehicles made in Korea, finite element analyses for concentrated wheel l oads were conducted by referring to the influence surfaces. Based on the ob tained member forces, the equivalent vehicle load factors for slabs which r epresent the ratios of member forces under vehicle loads to those under uni formly distributed loads were determined. In addition, the relationships be tween the equivalent vehicle load factors and sectional dimensions were est ablished by regression, and those are used to obtain the design moments by vehicle loads. The member forces calculated by the proposed method are comp ared with the results of four different approaches described in current des ign codes with the objective being to establish the relative efficiencies o f the proposed method. (C) 2001 Published by Elsevier Science Ltd.