การกระจายทางสถิติของปัจจัยที่มีผลต่อความสามารถในการรับแรงของชิ้นส่วนโครงสร้าง คสล.

Abstract

1008-38 Reinforced Concrete Design Standards adopted the design margins including load factors and strength reduction factors from the ACI318 standards. These design margins are based on American statistical data. The adoption of these margins may or may not suitable for the designing of structures in Thailand. It would be more appropriate to select the design margins based on the statistical data collected in Thailand itself. These data include (1) distributions of the loads which affect the internal forces of the structural members and (2) the distributions of the member sectional sizes, rebar sizes, concrete and steel strengths and also the location of the rebars which affect the load capacity (Resistance) of the members. This paper presents the selection of the most suitable standard distributions (Fit Distribution) including beam width, column size, footing width and length, actual size and yield load of rebars, ultimate strength of concrete, effective depth of beams and footings. These data were collected from the residential construction sites in Bangkok metropolitan area. The result from this analysis will be preliminary used for the selection of the appropriate design margins for Thailand reinforced concrete standards in the future.