Graduation Semester and Year




Document Type


Degree Name

Master of Science in Civil Engineering


Civil Engineering

First Advisor

Nur Yazdani


The purpose of this research is to evaluate a method proposed by Franz Dischinger (Dischinger, 1939) to consider the effects of a variable modulus of elasticity (MOE) of concrete over a period of time. Current guidelines suggested by the American Association of State Highways and Transportation Officials (AASHTO) assume a constant value for the MOE and base its calculation on the unit weight of concrete and the twenty eight day compressive strength of concrete. A few methods such as the ACI 209 Model Code (ACI 209, 1982) and CEB-FIP 1990 (CEB-FIP 1990, 1990) provide guidelines for the calculation of a variable modulus of elasticity. Dischinger's method varies the MOE through the use of a concrete creep function. The values of the time dependent MOE for each of the methods have been compared. Specifically this research focused on the effect Dischinger's method has on prestress losses in a prestressed concrete beam. This research also compared the losses between all three methods. The results showed that Dischinger's theory provides for higher values of modulus of elasticity and predicts higher losses. Over a period of time the prestress losses become constant. This is extremely useful since it can be used in conservative beam design.


Civil and Environmental Engineering | Civil Engineering | Engineering


Degree granted by The University of Texas at Arlington