An Experimental and Numerical Investigation on Performance of Steel Beams with Square Web Openings

Abstract

In the present study, experimental and numerical investigation is carried out to study the effect of size of square openings on the performance of steel beams. Steel I section ISMB150 @ 14.9 kg/m, of 900 mm overall span and 800 mm effective span is chosen for the experimental and numerical investigation with a simple support condition at both the ends. Performance of ISMB 150 section without and with square web openings of size 50 mm, 75 mm and 100 mm is studied in the present investigation. Experimental analysis is performed by subjecting the steel sections to mid-point loading in Universal Testing Machine. Whereas numerical analysis is performed for the steel sections using ANSYS FEM software. ANSYS FEM software predicts the similar variation of load-deflection curves as that of experimental results for all the steel beams. From both experimental and numerical investigation, solid beam without web opening takes more load and deflects less as compared to steel beams with square web openings. Further, as size of square opening increases, load carrying capacity decreases and deflection at mid-span increases.

Introduction

Steel structures are favored in modern construction for their high strength, durability, and adaptability, supporting heavy loads over wide spans and enabling faster prefabricated assembly. Traditional solid-web steel beams can restrict the installation of services like HVAC ducts and pipelines, which has led to the adoption of steel beams with web openings. Proper design of these openings is critical, following INSDAG guidelines regarding location, spacing, and size, as openings alter stress distribution and failure mechanisms.

This study investigates ISMB150 steel I-section beams—both solid and with square web openings of varying sizes—through experimental testing and numerical simulation. Experimentally, beams were subjected to three-point loading on a Universal Testing Machine, with deflection measured at mid-span using LVDTs. Corresponding 3D finite element models were developed in ANSYS, applying material properties, boundary conditions, and mid-point loading to analyze structural behavior. The results, including load-deflection curves, allow comparison between solid and perforated beams, providing insights into performance changes due to web openings.

Conclusion

In the present study, experimental and numerical investigation is carried out to study the effect of size of square openings on the performance of steel beams. Steel I section ISMB150 @ 14.9 kg/m, of 900 mm overall span and 800 mm effective span is chosen for the experimental and numerical investigation with a simple support condition at both the ends. Performance of ISMB 150 section without and with square web openings of size 50 mm, 75 mm and 100 mm is studied in the present investigation. Experimental analysis is performed by subjecting the steel sections to mid-point loading in UTM and numerical analysis is performed for the steel sections using ANSYS FEM software. The important conclusions drawn from the present study are as follows. 1) All the steel beams show similar variation in load-deflection curve when tested experimentally in UTM and when analyzed numerically in ANSYS FEM software. 2) ANSYS FEM software predicts the similar variation of load-deflection curves as that of experimental results for all the steel beams. Also, FEM results match fairly well with the experimental results. 3) From both experimental and numerical investigation, solid beam without web opening takes more load and deflects less as compared to steel beams with square web openings. Further, as size of square opening increases, load carrying capacity decreases and deflection at mid-span increases.

References

[1] Resmi M and Preetha P (2016), “Finite Element Analysis to Compare the Deflection of Steel Beam with and without Web Openings”, International Organization of Scientific Research Journal of Civil Engineering. [2] Mork hade G and Gupta M (2015), “An Experimental and Parametric Study on Steel Beams with Web Openings”, International Journal of Advanced Structural Engineering. [3] Morkhade G and Gupta M (2021), “Experimental and Analytical Investigation of Castellated Beams with Varying Openings Eccentricity”, Journal of the institution of engineers, Vol. 102. [4] SP 6 (Part 1):1964, “Code of Practice for Structural Steel Sections”, Bureau of Indian Standards, New Delhi, India. [5] IS 800 :2007, “General Construction in Steel Code of Practice”, Bureau of Indian Standards, New Delhi, India. [6] Institute for Steel Development and Growth (INSDAG) Manual

Copyright

Copyright © 2025 Puneeth N R, Chidananda G. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.