Experimental Verification of the Influence of Axial Force on the Shear Resistance of Prestressed Beams with Shear Reinforcement

Abstract:

In prestressed elements with shear reinforcement, according to the current design procedures EN 1992-1-1 (2004), the effect of axial force is taken into account by using a lower angle θ of the compression concrete strut compared to reinforced concrete elements. However, there is no direct procedure for calculating this angle and it is up to the experience and discretion of the designer, who may take into account the recommendations of the authors of professional publications. The article deals with the theoretical evaluation and experimental load test of the shear resistance of prestressed beams. It examines the effect of axial force on the shear resistance with shear reinforcement, which in the analyzed element is greater than that defined by the minimum degree. The theoretical analysis evaluates the approach of the design model for shear with shear reinforcement according to EN 1992-1-1 with experimentally obtained values. The analysis is also based on the results of an experimental campaign. The beam with a standardized cross-section, which is still used today for concrete road bridge structures, was tested. The full-scale experiment was therefore carried out on a 600 mm high beam with an I-shaped cross-section. The total length of the experimental beam was 7.0 m, while the effective span of the beam during testing was 4.9 m, which allowed obtaining 2 results from testing one element. The result is the demonstration of a positive influence of axial force on the shear resistance of an element with shear reinforcement, although the level of influence is not significant.

• Periodical: Advances in Science and Technology (Volume 176)
• Pages: 75-82
• DOI: https://doi.org/10.4028/p-4tXyaS
• Online since: May 2026
• Authors: Viktor Borzovič*, Jaroslav Baran
• Keywords: Load Test, Prestressed Beam, Shear Reinforcement, Shear Resistance

References

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