Abstract: This paper discusses a new,practical method of whole-field stress analysis provided through the combination of 3-D photoelasticity analysis and numerical calculation,that is,partial-differential equations,after being converted into difference iteration formulae,to be programmed and realized in IBM-PC-XT minicomputer.The method proved effective by the 3-D photoelasticity calculation of the experimental data obtained from a girderless floor structure,without column cap.