Date of Award

Summer 8-2022

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Civil Engineering (MCE)

Department

Civil Engineering

Advisor

Eric Landis

Second Committee Member

Roberto Lopez-Anido

Third Committee Member

Jameson Shannon

Abstract

UHPC with the addition of fibers is recognized for its increased impact resistance compared to typical strength concrete. To further increase the resilience, recent studies have been conducted to reinforce the UHPC with CFRTP on the front and rear face to create sandwich panels. These studies used PETg/E-glass CFRTP bonded to the UHPC using EMAA (Surlyn) in a stamp thermoforming process. Impact tests conducted on these panels have shown that delamination has been the initial and detrimental failure to the sandwich composite. Increasing the composites resistance to debonding will increase the impact energy required to debond the composite. In this study the bond capability of EMAA (Surlyn) was investigated in an attempt to increase the bond strength and improve the composite sandwich panels impact resilience. Single lap shear and CFRTP reinforced beam bending tests were conducted to investigate the bond of the EMAA to the CFRTP and UHPC respectively. The different glass transition temperatures of EMAA and PETg proved to cause the complication of bubbling in the EMAA between the PETg and UHPC. In an attempt to remove the need for PETg, trials were conducted to create a new CFRTP using CSM E-glass fibers and EMAA matrix. This new CFRTP was created and was able to successfully bond to the UHPC core to create a new Surlyn CSM impact panel. Impact tests of 50 J were i conducted on the two thermoplastic panels and two other panels fabricated using a two-part epoxy and a Urethane adhesive with the PETg CFRTP. The compliance was found before and after impact to measure the damage due to impact. The two-part epoxy and Surlyn CSM panel experienced the lowest amount of damage. However, the Surlyn CSM panel dissipated the least amount of energy due to impact.The original CFRTP/Surlyn Composite panel absorbed the most energy from the impact while presenting the most damage due to major delamination of the panel. The Surlyn CSM panel provided the lowest deflection during impact and the least amount of calculated and visualized damage.

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