A description is given of a survey of live loads on slab formworks in
multistory concrete buildings during construction. The survey was cond
ucted during the period 1987 to 1990 and embraced over 22 concrete bui
lding projects in several different cities. In this survey, data were
collected on the materials and equipment stored on slab formworks and
the worker's load. The live loads supported by slab formworks change c
ontinuously during construction. This paper studies the live loads on
formworks before the concrete slab is poured. The survey procedure and
a statistical analysis of the collected data are presented. The stati
stical moments of equivalent uniformly distributed loads for formwork
member load effects are obtained by using the covariance function deve
loped for the observed live loads and formwork member load effect infl
uence surfaces. A distribution function for formwork member load effec
ts is investigated and fractiles of the calculated equivalent uniforml
y distributed loads are compared with the current formwork minimum des
ign load recommendations.