Date of Award

12-2015

Level of Access

Campus-Only Thesis

Degree Name

Master of Science (MS)

Department

Civil Engineering

Advisor

Eric N. Landis

Second Committee Member

Roberto Lopez-Anido

Third Committee Member

Anthony M. Viselli

Abstract

A post-tensioned, floating, lightweight concrete prototype was produced for the purpose of testing constructability issues, joint technologies, post-tensioning issues, and long-term durability of a lightweight concrete mix in severe marine conditions. A segmental concrete specimen 8.5 feet wide, 4 feet tall, and over 32 feet in length was designed and built with five segments and four joints. The joints were coated with adhesive then post-tensioned together. To test the strength and water-tightness of the joints, the cavities were filled with water and the structure was subjected to a four-point bend. This applied stress to the structure as a whole and tested the water-tightness of the joints when they were subjected to both tensile stress and water pressure. Results showed that the adhesive joints performed similarly to monolithic concrete. Additional testing was done to evaluate model predictions of load-deformation response and post-tensioning losses. The structure was subjected to 494,197 fatigue cycles with a load varying from 3% to 27% of the failure load. No change in stiffness was measured, nor was there any significant joint leakage. After the in-lab testing, the prototype was transported to Treat Island for extreme environment testing, and, if successful, to be used as a test platform for future specimens.

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