Date of Award

Spring 5-6-2016

Level of Access

Campus-Only Thesis

Degree Name

Master of Science in Civil Engineering (MSCE)

Department

Civil Engineering

Advisor

William Davids

Second Committee Member

Roberto Lopez-Anido

Third Committee Member

Eric Landis

Abstract

Researchers at the University of Maine have developed structural arch bridge members made of Concrete-Filled Fiber Reinforced Polymer tubes (CFFT’s). These structural members have been proven to be a viable bridge support option where CFFT arches are cast in concrete footings and placed parallel to the roadway. Composite decking is attached to the CFFT arches, a granular backfill is completed, and asphalt is placed on top of the soil. The Fiber Reinforced Polymer (FRP) composite shell primarily provides tensile capacity, shear strength, and confinement while the concrete primarily provides compressive capacity. CFFT arch bridges can have several advantages over traditional steel or reinforced concrete bridges, including faster construction times, low maintenance requirements, and increased lifespans. CFFT arches have been approved for use by AASHTO, and are currently in use in several states in the U.S.

A limitation of this technology is that it is difficult and expensive to ship longer span arches. Previous research at the University of Maine has developed a splice in order to ship two or more smaller arch segments to the site and fasten them together with an external collar and mechanical fasteners. Steel reinforcing was used at the splice to provide concrete reinforcement at the apex where the largest moments occur.

This thesis investigates an alternative splice that uses an internal FRP collar bonded to the FRP shell with a high-strength urethane adhesive and Carbon Fiber Composite Cable (CFCC) reinforcing, ensuring an all-FRP composite bridge technology. Experimental work includes CFCC pull out testing, lap shear testing to obtain adhesive strength, hollow beam testing to assess the internal collar’s ability to withstand short-term concrete filling and construction loads, filled beam testing to assess the CFCC reinforced splice moment capacity, and arch testing to assess the CFCC reinforced splice moment capacity in the presence of the axial compressive forces it must also resist when used in an arch. Results showed that the splice is structurally adequate, but not as strong as an un-spliced CFFT arch section. Further testing, analysis, and design improvements should be conducted to better assess and improve the splice performance.

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