JavaScript must be enabled in order to use this site.Please enable JavaScript in your browser and refresh the page. General Design Approach Strip and Section Design – A 3 Step Process Non-prestressed Reinforcement Stress-Strain Curves Post-tensioning Material Stress-Strain Curves Relationship of Bonded Post-tensioning Strains to Cross-Section Strains Unbonded Post-tensioning Stress-Strain Curves – General Theory Unbonded Post-tensioning Stress-Strain Curves – Program Implementation Tendons – External Load or Internal Force? Tendons – inclusion of force vector on a cross section Tendons – calculation of number of ducts Concrete Stress-Strain Curves Creep and Shrinkage Effects Cracked Section Analyses Branson’s Stress Ratio Calculation of Effective Curvature Ratio Use of ECR Crack Width Predictions "Cracking Moment" Used in Design Calculations Concrete Core Determination Torsion Considerations Wood-Armer Torsion Design Parent topic: Section Design Notes