Date of Award


Document Type


Degree Name

Master of Science (MS)


Mechanical Engineering


A theoretical model for the determination of the beam stiffness of a captive column loaded as a simple-supported beam with a concentrated midspan load is described. A captive column is a high strength, light-weight composite structural member. Due to the composite nature of a captive column, the deflection due to shear forces, which is neglected in typical beam applications, must be included in the determination of the lateral deflection. The total deflection is obtained by setting the elastic strain energy stored in the captive column equal to the work that is applied to the column. The effects of changes in individual design parameters are investigated using the theoretical model. Experimental data was obtained to verify the theoretical model and the effects of changes in individual design parameters. Comparisons are also made between beam stiffness values obtained from the theoretical model and a finite element computer model.

Comparisons between beam stiffness values obtained from the theoretical model, experimental testing, and the finite element model indicate that the theoretical model can be used to determine captive column beam stiffness or to predict the effect of a change in an individual design parameter. Sources of error in the experimental results and possible areas of improvement in the theoretical model are identified and discussed.