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:

DOWNLOAD EBOOK

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.

High Performance Concretes
High Performance Concretes

Author: Paul Zia

Publisher:

Published: 1991

Total Pages: 262

ISBN-13:

DOWNLOAD EBOOK

This state-of-the-art report summarizes the results of an extensive search and review of available literature on the mechanical properties of concrete, with particular reference to high performance concrete for highway applications. Included in the review and discussion are the behavior of plastic concrete as well as the strength and deformation characteristics of hardened concrete. Both short-term and long-term effects are considered. Based on the review of the available information, research needs are identified. It is concluded that much research is needed to develop data on the strength and durability properties of concrete which develops high strength, particularly very early strength.

Fatigue of Reinforced Concrete
Fatigue of Reinforced Concrete

Author: G. P. Mallett

Publisher: Stationery Office Books (TSO)

Published: 1991

Total Pages: 180

ISBN-13:

DOWNLOAD EBOOK

Over the past 20 years, the Transport and Road Research Laboratory has carried out a co-ordinated programme of fatigue testing, including work on the fatigue performance of reinforced and pre-stressed concrete beams. The research has led to a better understanding of the fatigue behaviour of plain concrete, the various types of reinforcing bars in air and concrete, continuous welded, lapped and coupled bars, and the effects of corrosion. The work of TRRL and many other organizations is reviewed and a summary of current design rules with recommendations for assessing the fatigue life of new structures in service is given.

Evaluation of Fatigue and Toughness of Fiber Reinforced Concrete as a New Highway Pavement Design
Evaluation of Fatigue and Toughness of Fiber Reinforced Concrete as a New Highway Pavement Design

Author: Matthew James Mulheron

Publisher:

Published: 2015

Total Pages: 95

ISBN-13:

DOWNLOAD EBOOK

Concrete pavement design is currently centered on steel reinforcement. Whether that reinforcement be in the form of dowel bars, as is the case in jointed plain concrete pavement (JPCP), or in the form of continuous rebar reinforcement, continuously reinforced concrete pavement (CRCP). The use of steel in concrete pavements presents durability problems due to the corrodibility of steel. This study evaluates the use of polypropylene fibrillated, polypropylene macro, and carbon fiber fibers as primary reinforcement in concrete pavements for the Louisiana DOT. Results showed that fiber reinforcement can be used to improve both the fatigue and toughness performance of concrete. When post-cracked strength or toughness is the concern, concrete containing more fibers and fibers with higher tensile strength are desirable. Carbon fibers maintained greater load-carrying capacity at lower deflections than the steel fibers, which produced the greatest ductility. However, toughness and fatigue performance did not correlate for small deflections, suggesting that polypropylene macro fibers may be adequate for repeated, low stress loading. This study also found that when repeated low deflections are a concern, such as with pavements, there must be sufficient fibers across a crack to maintain a tight crack. Conversely, too many fibers prevent adequate consolidation and aggregate interlock, which negatively influences performance. When considering the pre-cracked fatigue performance of fiber reinforcement, the fibers needed to have sufficient length to reach across the crack and bond with the concrete, and that higher fiber dosages increase the fatigue performance of the concrete. The resulting pavement design, continuously fiber reinforced concrete pavement (CFRCP), will provide an alternative to JPCP and CRCP in highway pavement design that is not susceptible to durability problems associated with corrosion of the reinforcement.

Ultra-High Performance Fiber Reinforced Concrete Behavior Under Impact Loading
Ultra-High Performance Fiber Reinforced Concrete Behavior Under Impact Loading

Author: Mostafa Hassan

Publisher:

Published: 2018

Total Pages: 126

ISBN-13:

DOWNLOAD EBOOK

Increasing the dynamic resistance for the structures is one of the benefits of using ultra high performance concrete (UHPC) and ultra-high performance fiber reinforced concrete (UHP-FRC). This current research focuses on the ultimate compressive and tensile impact strength represented by the dynamic increase factor (DIF), the ratio between the dynamic strength and the quasi-static strength, for UHPC and steel fiber ultrahigh performance concrete (SF-UHPC) using split Hopkinson pressure bar (SHPB). The main goal is to obtain and validate the experimental test results of UHPC and UHP-FRC under high compressive and tensile strain rate range from 22-200 s -1 . Also, Achieving the experimental requirements for the dynamic testing using the SHPB for brittle materials (having stress equilibrium (SE) during the test, constant strain rate (CSR) over an effective time period, and reducing the inertial, friction, and wave dispersion effects). Different steel mono-fiber volume fraction content (0% - 4%) will be used to develop a general equation for the (DIF) for the SF-UHPC with a compressive strength exceeds 200 MPa. The quasi-static and the dynamic compression strength for UHPC and SF-UHPC with different volume fraction was reported. Digital image correlation (DIC) was used to monitor the strains of some samples using a high speed camera at 105,000 - 186,000 frames per second and thus to compliment the calculated strain values that was obtained by the SHPB equations. A three-dimensional finite element analysis has been performed using ABAQUS/Explicit to model multiimpacts on UHPC to check the frictional effect contribution to the DIF and the validity of the constitutive model in representing the behavior of UHPC. Finally, addressing the tensile static and dynamic behavior of UHP-FRC. Static tensile test according to the ASTM requirements is used while modified dynamic tensile setup of split Hopkinson tensile bar (SHTB) is used to determine the dynamic behavior and the dynamic increase factor (DIF) for UHP-FRC under high strain rates ranging from 55.3 - 156.04 s-1.

Mechanical Behavior of High Performance Concretes
Mechanical Behavior of High Performance Concretes

Author:

Publisher:

Published: 1993

Total Pages: 324

ISBN-13:

DOWNLOAD EBOOK

Summary report: This report presents a summary of each phase of a 4-year research program of the Strategic Highway Research Program (SHRP), which examined the mechanical behavior of high performance concretes. -- Production of high performance concrete: This report details the laboratory developmental work on producing high performance concrete for highway applications. -- Very early strength (VES)concrete: This report details the laboratory investigation of the mechanical behavior and field trials of high performance concrete for highway applications, and more specifically, VES concrete. -- High early strength (HES) concrete: The objective of this particular investigation is to obtain information on the mechanical behavior of HES concrete and to demonstrate its use under field conditions. -- Very high strength (VHS) concrete: The objective of this particular investigation is to obtain information on the mechanical behavior of VHS concrete. -- High early strength fiber reinforced concrete: This study provides an extensive data base and a summary of a comprehensive experimental investigation on the fresh state and mechanical properties of high early strength fiber reinforced concrete (HESFRC).