Performance Benefits of Fiber-reinforced Thin Concrete Pavement and Overlays
Performance Benefits of Fiber-reinforced Thin Concrete Pavement and Overlays

Author: Manik Barman

Publisher:

Published: 2021

Total Pages: 176

ISBN-13:

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This study investigates the performance benefits of synthetic structural fibers in mitigating distresses in thin concrete pavements and overlays. In this study, two ultra-thin (3 and 4 inches thick) and four thin (5 and 6 inches thick) concrete pavements placed on a gravel base along with two thin unbonded concrete overlay cells (5 inches thick) placed on an existing concrete pavement were constructed at the Minnesota Road Research (MnROAD) facility in 2017. This report discusses the objectives and methodology of the research, including the construction of the test cells, instrumentation, traffic load application, and data collection and analysis procedures. The structural responses and distresses observed over three years, such as fatigue cracking and faulting, as well as the joint performance measured in each cell, were discussed and compared in this report.

Comparison of Performances of Structural Fibers and Development of a Specification for Using Them in Thin Concrete Overlays
Comparison of Performances of Structural Fibers and Development of a Specification for Using Them in Thin Concrete Overlays

Author: Manik Barman

Publisher:

Published: 2018

Total Pages: 275

ISBN-13:

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Structural fibers improve the long-term performance of concrete pavements and overlays and potentially are useful to reduce the slab thickness. These fibers are available in different parent material compositions, stiffness, shapes, and aspect ratios. The main objective of this study was to characterize the post-crack flexural and joint performance of fiber reinforced concrete to develop a specification for the selection of structural fibers for concrete overlays and/or pavements. The study included a literature review, an online survey, and a large-scale laboratory testing. It was found that the majority (almost 94%) of the FRC overlays in this country were constructed with structural synthetic fibers, which provided equal or better performance than projects using the steel fibers. In the laboratory study, a total of 43 different mixes were prepared with 11 different types of fibers. Fiber dosage, stiffness, and geometry significantly influenced the residual strength ratio (RSR) and residual strength (RS). In general, embossed, twisted, and crimped fibers performed better on average than straight-flat synthetic fibers when the comparison was made in terms of RSR or RS. From the joint performance testing, it was found that fibers can greatly improve the performance of the pavement with respect to load transfer efficiency (LTE), differential displacement, and differential joint energy dissipation. The findings from this were used to recommend the target ranges post-crack flexural performance, and joint performance parameters.

Evaluation of a Polyvinyl Alcohol Fiber Reinforced Engineered Cementitious Composite for a Thin-bonded Pavement Overlay
Evaluation of a Polyvinyl Alcohol Fiber Reinforced Engineered Cementitious Composite for a Thin-bonded Pavement Overlay

Author: Alexandra Akkari

Publisher:

Published: 2011

Total Pages: 48

ISBN-13:

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A need arose at the MnROAD research facility to provide a thin beam structural overlay on a moderately deteriorated concrete pavement test cell. This research was done to evaluate a polyvinyl alcohol fiber reinforced engineered cementitious composite (PVA-ECC) and assess the prospects to utilize the material in the bonded pavement overlay. PVA-ECC is a ductile material that can achieve extremely high flexural strength and tensile strain capacity, characteristics which can prevent reflective cracking in pavement. The PVA-ECC mix was tailored by including coarse aggregate to maintain some of the benefits of typical concrete pavements. Workability, flexural and compressive strength, ductility and durability tests were done to assess the performance at varying fiber contents. Results show that fiber at 16 lbs/cy achieved the highest flexural and compressive strength, at 1030 and 6910 psi respectively. The paired student's t-test shows that 16 lbs/cy of fiber can improve flexural strength by between 150 and 300 psi with 95% confidence. This small increase and lack of any noticeable ductile behavior do not make the PVA-ECC beneficial for overlay applications. This research found that the modified PVA-ECC with the low doses of fiber examined in this study are not suitable for the overlay at MnROAD.

Thin and Ultra-thin Whitetopping
Thin and Ultra-thin Whitetopping

Author: Robert Otto Rasmussen

Publisher: Transportation Research Board

Published: 2004

Total Pages: 96

ISBN-13: 0309070198

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TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 338: Thin and Ultra-Thin Whitetopping summarizes available information to document how state departments of transportation and others are currently using thin and ultra-thin whitetopping overlays among various pavement rehabilitation alternatives. The report covers all stages of the proper application of whitetopping overlays, including project selection, design, materials selection, construction, maintenance, and eventual rehabilitation or replacement.

The Effect of Concrete Strength and Fibre Content on the Fatigue Performance of Ultra Thin Continuously Reinforced Concrete Pavement (UTCRCP)
The Effect of Concrete Strength and Fibre Content on the Fatigue Performance of Ultra Thin Continuously Reinforced Concrete Pavement (UTCRCP)

Author: Andrew Michael Mackellar

Publisher:

Published: 2016

Total Pages:

ISBN-13:

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Ultra Thin Continuously Reinforced Concrete Pavement (UTCRCP) is an innovative road paving technology that can have significant advantages over traditional road paving techniques. Full scale testing has shown that UTCRCP can carry in excess of one hundred million E80s (standard 80 kN axle loads). The concrete used for the construction of UTCRCP is high strength and contains steel fibres. The purpose of this study is to investigate the effect of varying the concrete strength and fibre content on the mechanical properties of the concrete used to construct UTCRCP. In this study testing is restricted to laboratory methods. Fibre reinforced concrete is often tested with the same tests as those used for plain concrete. These are not adequate to fully capture the effects of the steel fibres. A number of test methods are used in this study and their suitability and shortcomings are discussed. Additionally, fatigue tests are conducted and a number of performance measures are used to track the fatigue damage. It was found that higher concrete strength and high fibre content did not necessarily result in highest performance in all cases. It was also found that there is not a single concrete strength or fibre content that always results in the optimum performance in all cases. For example the concrete strength and fibre content that produced the best results for tensile strength was not the best mix for energy absorption at high deflections. When selecting the concrete strength and fibre content for use in construction the application of the concrete element must be carefully understood. Based on this the designer can then select which of the concrete performance characteristics are of most importance to the desired application. Once this is done an appropriate concrete strength and fibre content can be selected.