Semester

Spring

Date of Graduation

2009

Document Type

Thesis

Degree Type

MS

College

Statler College of Engineering and Mineral Resources

Department

Civil and Environmental Engineering

Committee Chair

Julio F. Davalos.

Abstract

High-performance concrete (HPC) is increasingly used in bridge decks due to its high strength, superior durability and low maintenance resulting in durable and cost effective bridges. FHWA strongly recommended developing suitable HPC mixtures using local material sources and construction technologies for a specific location or state.;As part of a comprehensive R&D program, a field implementation of laboratory developed HPC mixtures was proposed. From a total of eight mixtures developed in the lab with w/cm=0.40, three HPC mixtures were selected using specific local aggregates, in addition to supplementary cementitious materials and chemical admixtures. From these mixtures, three test slabs were produced at a concrete plant in West Virginia, by simulating typical construction practices. The plant-produced slabs were monitored and evaluated for temperature, weather, fresh, hardened, and durability properties for over 90 days from summer to early winter. Maturity-strength relationships were established. Microscopic determination of air-void parameters were conducted using a proposed new method and compared with standard method. Finally, concrete cores were examined by petrography to determine w/cm ratio, compositional variations, and other possible depositions within hardened slabs. The properties of field-mixed match-cured, field-mixed laboratory-cured and laboratory-mixed specimens were compared to check the performance of concrete designed in the laboratory and used in the field.;The results showed that all combinations performed well, with slag + silica fume combinations being the best in terms of compressive strength, resistance to freezing and thawing, and chloride ions penetration. The proposed new method for estimating the air-void parameters was found to be more representative than standard methods. The petrographic examination revealed that aggregates, w/cm ratio, and cementitious materials contents were consistent with the original mixture design. This study will be used to develop guidelines for full-scale demonstration projects for the state of West Virginia.

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