Suitability assessment of the partial safety factors of CP110 used in the design of ultimate strength of reinforced concrete columns

Abstract

Empirical data were used to assess the suitability of the partial safety factors in the Code of Practice CP110 which are often used in the design of the ultimate strength of reinforced concrete section. To do this, the effects of short term variables that affect the ultimate strength of a rectangular column section was studied using Monte Carlo technique by the input of statistical parameters of these variables into a computer
program designed for the computation. Simulation of 1000 columns at selected eccentricities was done and the distribution of strength was determined. The interaction
curve obtained from this simulation was compared with the theoretical curve obtained when the nominal values of the parameters were used. It was found that the safety
factors varied at different eccentricity from those obtained when the nominal values were used for the computation of strength. This in turn calls for additional strength reserve in
the use of the curve provided for in the code.