ABOUT THE DESIGN OF PRESTRESSED FRAMES WITH THE INFINITELY RIGID BEAM, SUBJECTED TO HORIZONTAL FORCES

Abstract

A design method of frames with the infinitely rigid beam and prestressed columns by high strength tie bars, is presented. After a brief reminder of the equivalent section method the calculation formulas of displacement stiffness for the basic systems are established. The conclusion is reached that the displacement stiffness of these bars can be determined by the formula kp = k ⋅ρ where k is the stiffness known for unprestressed bars (without tie bars) and ρ a correction factor, which depends on the prestressing degree and type of basic system. The other parameters which appear in the calculation relationship of the factor ρ , have a very small importance. The relationships corresponding to these correction factors of the displacement stiffness of the prestressed columns are given.