Computerized Optimum Dimensioning of Prestressed Homogenous Steel I-Beam

  • Ponnada Markandeya Raju Maharaj Vijayaram Gajapathi Raj College of Engineering
  • Ravindra Vipparthy Jawaharlal Nehru Technological University Kakinada


Download data is not yet available.


The economy of a prestressed steel beam can be realized only when relevant parameters of optimum magnitude are chosen. The present work aims at finding out the optimum dimensions of a simply supported, laterally unsupported, prestressed steel I-beam for a given span and load carrying capacity. The span of the beam was limited to 12 m while the load carrying capacity was limited to 100 kN/m for this study. A straight tendon configuration over the whole span is considered and the losses occurring in the tendon are neglected. The safety of various sets of dimensions ranging from the minimum dimensions of I-section in IS-Hand Book-1 to their maximum dimensions for different pre-stressing forces and eccentricities are checked. The set with minimum cross sectional area is chosen. Iterative calculations involved in analysis were performed with the help of a ‘C’ program developed by the authors in Turbo ‘C’ Environment. It was observed that the ratio of top fiber stress at working loads to the permissible stress is more than 0.9 for all the spans for the finalized cross-sections. This means that the cross-section is being effectively utilized. For a given load carrying capacity and span, eccentricity to depth ratio has to be in between 0.45 to 0.7 for optimum utilization of the available cross section. It is also observed that the maximum pre-stressing force equal to 0.25 times the permissible bending compressive stress can be applied.

View article in other formats
Author Biographies
Ponnada Markandeya Raju

Maharaj Vijayaram Gajapathi Raj College of Engineering, Vizianagaram, Andhra Pradesh 535005, India

Ravindra Vipparthy

Jawaharlal Nehru Technological University Kakinada, Kakinada, Andhra Pradesh 535005, India

Vol 21 No 7, Dec 29, 2017
How to Cite
P. Raju and R. Vipparthy, “Computerized Optimum Dimensioning of Prestressed Homogenous Steel I-Beam”, Eng. J., vol. 21, no. 7, pp. 293-318, Dec. 2017.

Authors who publish with Engineering Journal agree to transfer all copyright rights in and to the above work to the Engineering Journal (EJ)'s Editorial Board so that EJ's Editorial Board shall have the right to publish the work for nonprofit use in any media or form. In return, authors retain: (1) all proprietary rights other than copyright; (2) re-use of all or part of the above paper in their other work; (3) right to reproduce or authorize others to reproduce the above paper for authors' personal use or for company use if the source and EJ's copyright notice is indicated, and if the reproduction is not made for the purpose of sale.

Article Statistics
Total PDF downloads: 230