Computer analysis of reinforced concrete cross-sections




Farahany, Mohsen M.

Journal Title

Journal ISSN

Volume Title




Analysis of the flexual behavior of reinforced concrete sections can be very time-consuming and repetitious. Examples of such procedures are the calculation of moment-axial force interaction diagrams for reinforced concrete columns, and the calculation of moment-curvature diagrams for reinforced concrete beams and columns. These diagrams are often used for analyzing structures as a whole. For instance, from the initial slope of the moment-curvature diagram, the cracked moment of inertia of a section can be calculated and used in analyzing the structure. These calculations are especially tedious for a section with a general arrangement of reinforcing steel or a general concrete cross-section. In most cases, the solution to this problem is to perform the necessary calculations using a computer program. Nonlinear stress-strain behavior of both steel and concrete, while impractical to consider in hand calculations, can be conveniently included in computer solutions. One such program is RCCOLA [5], originally developed at the University of California at Berkeley. RCCOLA calculates moment capacities, shear capacities, yield ductilities and curvatures at a series of given axial loads, for different specified extreme compressive strains of concrete, in reinforced concrete cross-section. In its original form, RCCOLA was relatively inconvenient to use. The input data were difficult to code. The printed output was confusing, and no plot routines were available. The available stress-strain relationships for concrete did not reflect the results of recent research, and the options for computing shear resistance of columns were limited. [...] The objectives of the work described in this report were 1) to revise the input and output formats for RCCOLA, making them more user-oriented; 2) to develop a series of subroutines permitting the results to be plotted on the ZETA plotter at the University of Texas; 3) To include, in the program, stress-strain models for confined concrete which reflect the results of recent research; 4) To include, in the program, recently developed models for predicting the shear capacity of short columns; 5) to eliminate some problems associated with the operation of the original program; and 6) to update, revise, and document the existing user's manual