Serviceability floor loads

Abstract

Serviceability of structures has to be verified for a lower load level than the design load used for safety considerations. Representative values of actions used in serviceability load combinations are often defined in a way that the fraction of time spent above a given load level should be limited to a certain value. To determine these load levels more information on the stochastic nature of the loading process is needed than to estimate the design load.A convenient way in structural design codes is to express representative values (rare, frequent and quasi-permanent) as a fraction of the characteristic value by using load reduction factors. However, the characteristic value is usually defined in a different way i.e. with a certain probability of not being exceeded (in a chosen period of time).The current paper estimates representative values of floor live loads by numerical simulation using stochastic live load models with a special focus on serviceability. The results are compared to values given in existing standards (Eurocode on first place). Improvements are suggested concerning the load reduction factors, the definitions of the representative values and the stochastic load parameters.