Date of Thesis

Spring 2023


The Specifications for Aluminum Structures (2020) provides the standards that structural engineers follow for aluminum design. Included in these specifications are limit state equations that use strength properties to calculate a member’s initial yield, full yield, and rupture values. One limit state that the standards currently neglect is the torsional failure of solid bars. Torsion is the act of rotation caused by a twisting force, otherwise known as torque. Future installments of the specifications hope to include torsional yielding and rupture equations, so this study investigates the validity of these proposed equations.

Two different aluminum alloys were investigated for this research: 6061-T6 and 5052-H32. Both alloys are common structural material. In order to employ the proposed limit state equations, these alloys underwent torsion and tension testing. The results of the tension tests are displayed first, followed by the results of the torsion tests. Furthermore, each section divides the results according to the alloy of interest. The experimental strength properties determined from tension testing and the strength properties listed in the specifications were used to evaluate the torsional limit states. The yielding predictions, initial and full, were plotted with the torsion results in order to assess the legitimacy of the equations. The rupture predictions used table comparisons to assess the accuracy of the equations. Statistical analyses were conducted on the results to support the experimental findings. The results of both alloys confirmed that the proposed limit state equations for torsion are accurate. However, concerns were raised because the Specifications for Aluminum Structures appeared to overestimate the strength properties of the 5052-H32 alloy. Therefore, it was concluded that the equations are accurate, but the yield and ultimate strength values listed in the Aluminum Design Manual (2020) require further investigation. Recommendations for future work are also provided within this thesis.


Aluminum, Torsion, Aluminum Design Manual, 6061-T6, 5052-H32

Access Type

Honors Thesis

Degree Type

Bachelor of Science in Civil Engineering


Civil Engineering

First Advisor

Ronald D. Ziemian

Second Advisor

Stephen Buonopane

Third Advisor

Michael Reeks