A comparative analysis of various code recommendations indicate that maximum design value of moment of resistance of rectangular and flange of sections vary from 0.08f_ckbd² to 0.2f_ckbd², depending upon recommendations of stress block parameters.

Due to handling in some members like portal frames and masts sections are subjected to compression and bending and most compression members such as long columns and piles are subjected to bending moment and axial forces.

The load contour method of analysis, detailed by Nawy and generally termed Bresler-Parme counter method is ideally suited for design of biaxially loaded columns and design procedure is outlined following steps: give ultimate moments, determine larger of equivalent required, assumed cross section, verify ultimate load carrying capacity, calculate actual nominal moment capacity, moment value.

force of cable = 200kn, b = 100mm, d = 200mm
Bearing area A_br = (100�100) = 10000mm²,
Actual bearing pressure = (200�10³) / 10000 = 20n/mm².

Bennett has proposed design charts with dimensionless parameters expressed in terms of service loads and moments, and section properties and permissible stresses in concrete expressed as a fraction of characteristic strength se charts are useful in dimensioning columns of I section with non uniform prestress and allowing desirable tensile stresses in concrete as in class 3 type members.

The design essentially consists of determining cross section area of member and required prestressing force to safely support axial tensile load conforming to limit state of serviceability and collapse.

In members with thin webs such as I and T sections nominal shear reinforcements have to be provided to prevent cracking due to variations in temperature provisions for design of shear reinforcements prescribed in British, American and Indian standard have been dealt with in case off structural concrete members subjected to torsion, shear stresses develop depending upon type of cross section and magnitude of torque and shear stresses in association with flexural stresses may give rise to principal tensile stress value of which when it exceeds tensile strength of concrete results in development of cracks on surface of member.

Assuming an anchor plate of size 50mm by 50mm, punching area A_pun = (50�50) = 2500mm², A_br = 10000mm², maximum permissible bearing pressure = 0.48fci(A_br/A_pun) or 0.8f_ci whichever is smaller, f_b = 0.48x30x(10000/2500)1/2 = 28.8n/mm² or (0.8�30) = 24n/mm2².

The area of high tensile and un tensioned reinforcement required to mobilize desired flexural strength is computed using force equilibrium at limit state of collapse and force equilibrium rar depends upon pressures exerted in different conditions.

The compression failure mode develops under concentric loading and this type of failure mode develops under concentric loads and section is considered to have failed when concrete strain ?0 reaches a value of 0.02.