A test procedure for evaluating the impact behaviour of fibre reinforced concrete

AbstractThis research work concerns the impact behaviour of metallic fibre reinforced concrete. After a description of the experimental apparatus used, an air compressed gun, we present the main results in terms of stress–strain diagrams as a function of the strain rate. Then, we establish equations of a specific damage model which take account of the different phases of the behaviour law.

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A Four Novel Energy Pattern Factor Method for Computation of Weibull Parameter in Impact Strength Reliability of Fibre-Reinforced Concrete

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.12.16042 ◽

2018 ◽

Vol 7 (3.12) ◽

pp. 272

Author(s):

Gayathri R ◽

Murali. G ◽

Parthiban Kathirvel ◽

Haridharan M.K ◽

Karthikeyan. K

Keyword(s):

Reinforced Concrete ◽

Impact Strength ◽

Shape Parameter ◽

Failure Strength ◽

Fibre Reinforced Concrete ◽

Test Results ◽

Weibull Parameter ◽

Impact Failure ◽

Novel Method ◽

The Impact

Impact strength data is a noteworthy factor for designing airport pavements, civilian and military structures etc and it is ought to be modelled precisely. In order to achieve an appropriate modelling data, it is important to select a suitable estimation method. One such commonly used statistical tool is the two parameter Weibull distribution for modelling impact failure strength accurately besides the variations in test results. This study statistically commandsthe variations in the impact failure strength (number of blows to induce failure) of fibre reinforced concrete (FRC) subjected to drop hammer test. Subsequently, a four-different novel method for the computation of Weibull parameter (Shape parameter) based on the earlier researchers test results has been proposed. The accuracy of the proposed four novel method is demonstrated by comparing with power density method and verified with goodness of fit test. Finally, the impact failure strength of FRC is offered in terms of reliability. The proposed four NEPFM is very suitable and efficient to compute the shape parameter in impact failure strength applications.

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A Four Novel Energy Pattern Factor Method for Computation of Weibull Parameter in Impact Strength Reliability of Fibre-Reinforced Concrete

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.12.16041 ◽

2018 ◽

Vol 7 (3.12) ◽

pp. 272

Author(s):

Gayathri R ◽

Murali. G ◽

Parthiban Kathirvel ◽

Haridharan M.K ◽

Karthikeyan. K

Keyword(s):

Reinforced Concrete ◽

Impact Strength ◽

Shape Parameter ◽

Failure Strength ◽

Fibre Reinforced Concrete ◽

Test Results ◽

Weibull Parameter ◽

Impact Failure ◽

Novel Method ◽

The Impact

Impact strength data is a noteworthy factor for designing airport pavements, civilian and military structures etc and it is ought to be modelled precisely. In order to achieve an appropriate modelling data, it is important to select a suitable estimation method. One such commonly used statistical tool is the two parameter Weibull distribution for modelling impact failure strength accurately besides the variations in test results. This study statistically commandsthe variations in the impact failure strength (number of blows to induce failure) of fibre reinforced concrete (FRC) subjected to drop hammer test. Subsequently, a four-different novel method for the computation of Weibull parameter (Shape parameter) based on the earlier researchers test results has been proposed. The accuracy of the proposed four novel method is demonstrated by comparing with power density method and verified with goodness of fit test. Finally, the impact failure strength of FRC is offered in terms of reliability. The proposed four NEPFM is very suitable and efficient to compute the shape parameter in impact failure strength applications.

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LABORATORY STUDY ON THE INFLUENCE OF CASTING ON PROPERTIES OF ULTRA-HIGH PERFORMANCE FIBRE REINFORCED CONCRETE (UHPFRC) SPECIMENS

Journal of Civil Engineering and Management ◽

10.3846/13923730.2014.913680 ◽

2014 ◽

Vol 20 (3) ◽

pp. 380-379 ◽

Cited By ~ 4

Author(s):

Adam Zofka ◽

Miglė Paliukaitė ◽

Audrius Vaitkus ◽

Dominika Maliszewska ◽

Ramandeep Josen ◽

...

Keyword(s):

Reinforced Concrete ◽

High Performance ◽

Fibre Orientation ◽

Compact Tension ◽

Fibre Reinforced Concrete ◽

X Ray ◽

Fracture Testing ◽

Physical Changes ◽

The Impact ◽

High Performance Fibre

This paper presents a study on the effects of casting procedure and resulting fibre orientation on the properties of Ultra-High Performance Fibre Reinforced Concrete (UHPFRC). To investigate the impact of fibre orientation in the UHPFRC specimens, three approaches were employed. First, densities were measured from the top, middle and bottom zones of the cylinders to observe physical changes as the function of cylinder height. Secondly, two engineering fracture tests were performed in both compression and tension, and a comparison of fracture energies was conducted between different cylinder zones. While previous studies have explored the influence of steel fibres on the UHPFRC performance, the Semi-Circular Bending (SCB) and Disc Compact Tension (DCT) experimental setups have not yet been used in the UHPFRC fracture testing. Lastly, samples from different zones were scanned using X-ray computer tomography (X-ray CT). Both visual and digital image analysis of the X-ray scans were conducted in order to observe fibre orientation pattern changes within different zones. Although density calculations showed insignificant differences between different zones, fracture testing exhibited significant differences through the testing process as well as through fracture energy computations. Furthermore, X-ray CT demonstrated considerable differences in spatial fibre orientation with respect to two uniquely defined angles.

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Behaviour of Different Types of Concrete under Impact and Quasi-Static Loading

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.486.295 ◽

2013 ◽

Vol 486 ◽

pp. 295-300 ◽

Cited By ~ 3

Author(s):

Petr Máca ◽

Petr Konvalinka ◽

Manfred Curbach

Keyword(s):

Tensile Strength ◽

Reinforced Concrete ◽

Impact Loading ◽

High Performance ◽

High Performance Concrete ◽

Fibre Reinforced Concrete ◽

Static Conditions ◽

Direct Tensile ◽

Direct Tensile Strength ◽

The Impact

This paper describes mixture formulation of Ultra High Performance Fibre Reinforced Concrete (UHPFRC) with 2% of fibres by volume and its response to quasi-static and dynamic impact loading. The UHPFRC mixture was prepared using locally available constituents and no special curing or mixing methods were used for its production. In addition, the mechanical parameters of three other types of concrete, i.e. normal strength concrete (NSC), fibre reinforced concrete (FRC) and high performance concrete (HPC) is compared. The main properties assessed throughout the experimental work are compressive, flexural and direct tensile strength as well as response of tested concretes to impact flexural loading. The impact loading is produced by a vertically falling weight of 24 kg from the height of 1 m on concrete prisms. The strain rate increase corresponds to low-velocity impacts such as vehicle crash or falling rocks. Compressive strength of UHPFRC exceeded 130 MPa and its direct tensile strength was 10.3 MPa. This type of concrete also exhibited strain hardening both in flexure under quasi-static conditions and during impact. Based on the comparison of impact reactions, it was concluded that the resistance of UHPFRC to impact loading is superior compared to the referent types of concretes (NSC, FRC, HPC).

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Experimental procedure for determination of the energy dissipation capacity of ultra-high-performance fibre-reinforced concrete under localized impact loading

International Journal of Protective Structures ◽

10.1177/2041419618819506 ◽

2019 ◽

Vol 10 (2) ◽

pp. 251-265 ◽

Cited By ~ 3

Author(s):

Petr Konrád ◽

Radoslav Sovják

Keyword(s):

Reinforced Concrete ◽

Impact Loading ◽

High Performance ◽

Volume Fraction ◽

Concrete Specimen ◽

Basic Material ◽

Fibre Reinforced Concrete ◽

Significant Difference ◽

The Impact ◽

High Performance Fibre

Research presented in this article is aimed to investigate the ability of ultra-high-performance fibre-reinforced concrete to absorb and dissipate mechanical energy at elevated strain rate loading. Specimens made of ultra-high-performance fibre-reinforced concrete were subjected to the low-velocity impact using the new testing procedure where no fixed supports that hold the sample during the impact were applied. The fibre volume fraction of the ultra-high-performance fibre-reinforced concrete was set as the main test variable in the framework of this study and the volumetric fraction of fibres was ranging from 0.125% to 2%. A high-speed camera was used to measure velocities of the impactor and the ultra-high-performance fibre-reinforced concrete specimen before and after the impact. Consequently, the energy dissipated by the ultra-high-performance fibre-reinforced concrete specimen during the impact was calculated using a simple energy balance equation. To determine the basic material properties of ultra-high-performance fibre-reinforced concrete, quasi-static loading rate was applied and conventional methods were used. A significant difference between the values of dissipated energies for different loading rates and various fibre volumetric fractions was observed. It can be noted that the new procedure shows a reasonable approach for testing the fibre-reinforced cementitious composites under localized impact loading and is worthy of further optimization.

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Does the Carbon Fibre Coating Reinforcement Have an Influence on the Bearing Capacity of High-Performance Self-Compacting Fibre-Reinforced Concrete?

Materials ◽

10.3390/ma12244054 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4054

Author(s):

Krzysztof Ostrowski

Keyword(s):

Reinforced Concrete ◽

Carbon Fibre ◽

High Performance ◽

Concrete Structures ◽

Concrete Mixture ◽

Cement Matrix ◽

Plastic Behavior ◽

Fibre Reinforced Concrete ◽

Carbon Fibres ◽

The Impact

This study investigated the impact of the location of a carbon fibre coated reinforcement ring (CFCRr) inside the structure of high-performance self-compacting fibre-reinforced concrete (HPSCFRC). Nowadays, cement matrix is considered as an alternative binder when reinforcing concrete structures with composite materials. Due to the plastic behavior of composite structures at relatively low temperatures when carbon fibres are reinforced with epoxy resin, the author attempted to locate carbon fibres inside a concrete structure. Thanks to this, the reinforcement will be less vulnerable to high temperatures (during a fire) and more compatible with concrete. The fibres act as a perimeter reinforcement that is compatible with the concrete mixture. The position of the CFCRr in the structure of concrete has an influence on the load capacity, stiffness and stress-strain behavior of concrete elements. The research was conducted on circular shape short concrete columns and tested under axial compression. The results demonstrated that by including CFCRr inside a concrete specimen, the maximum compressive strength decreases with an increase in the number of composite rings and a greater distance from the vertical axis of symmetry to the edge of the element. It has been proven in these studies that carbon fibres do not have good adhesive properties between CFCRr and a concrete mixture. As a result of this phenomenon, a shear surface is created, which leads to crack propagation along the CFCRr. Therefore, the presented idea of an internal CFCRr should not be used when designing new concrete structures.

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Experimental Tests of Steel Fibre Reinforced Concrete Beams under Drop-Weight Impacts

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.626.311 ◽

2014 ◽

Vol 626 ◽

pp. 311-316 ◽

Cited By ~ 1

Author(s):

Yi Fei Hao ◽

Hong Hao ◽

Gang Chen

Keyword(s):

Reinforced Concrete ◽

Steel Fibre ◽

Concrete Beams ◽

Plain Concrete ◽

Fibre Reinforced Concrete ◽

Steel Fibres ◽

Steel Fibre Reinforced Concrete ◽

Impact Tests ◽

Drop Weight ◽

The Impact

Concrete is a brittle material, especially under tension. Intensive researches have been reported to add various types of fibres into concrete mix to increase its ductility. Recently, the authors proposed a new type of steel fibre with spiral shape to reinforce concrete material. Laboratory tests on concrete cylinder specimens demonstrated that compared to other fibre types such as the hooked-end, deformed and corrugated fibres the new fibres have larger displacement capacity and provide better bonding with the concrete. This study performs drop-weight impact tests to investigate the behaviour of concrete beams reinforced by different types of steel fibres. The quasi-static compressive and split tensile tests were also conducted to obtain the static properties of plain concrete and steel fibre reinforced concrete (FRC) materials. The quasi-static tests were carried out using hydraulic testing machine and the impact tests were conducted using an instrumented drop-weight testing system. Plain concrete and concrete reinforced by the commonly used hooked-end steel fibres and the proposed spiral-shaped steel fibres were tested in this study. The volume dosage of 1% fibre was used to prepare all FRC specimens. Repeated drop-weight impacts were applied to the beam specimens until total collapse. A 15.2 kg hard steel was used as the drop-weight impactor. A drop height of 0.5 m was considered in performing the impact tests. The force-displacement relations and the energy absorption capabilities of plain concrete and FRC beams were obtained, compared and discussed. The advantage and effectiveness of the newly proposed spiral-shaped steel fibres in increasing the performance of FRC beam elements under impact loads were examined.

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A Study on Fibre-Reinforced Concrete Elements Properties Based on the Case of Habitat Modules in the Underwater Sills

Polish Maritime Research ◽

10.2478/pomr-2020-0015 ◽

2020 ◽

Vol 27 (1) ◽

pp. 143-151

Author(s):

Marzena Kurpińska ◽

Beata Grzyl ◽

Adam Kristowski

Keyword(s):

Reinforced Concrete ◽

Construction Materials ◽

Hardened Concrete ◽

Fibre Reinforced Concrete ◽

Positive Effects ◽

Custom Made ◽

The Baltic ◽

Corrosive Environments ◽

The Impact ◽

Concrete Elements

AbstractHydrotechnical constructions are mostly objects functioning in extreme conditions and requiring a custom-made construction project. In the case of using prefabricated elements, it is required to develop production, transport, assembly, conservation and repair technology. Concerning the problem of concrete cracks, modern repair systems allow positive effects to be achieved in many cases of concrete elements repair. In this work an attempt has been made to assess the properties of concrete, situated in the Baltic Sea environment, in which traditional rebar was partly replaced by dispersed fibre-phase. Fibre-reinforced concrete belongs to the group of composite materials. The presence of fibres helps to increase the tensile strength, flexural strength and resilience and also prevents the appearance of cracks. In the given paper we will also discuss basic parameters of steel and polymer fibres and the influence of both types of fibres on the maturing and hardened concrete. In this work special attention has been paid to the advantages of polypropylene and polymer fibres with regard to commonly-known steel fibres. The use of synthetic fibres will be advantageous in constructions where the reduction of shrinkage cracks and high resilience are essential. On top of that, the use of synthetic fibres is highly recommended when constructing objects that will be exposed to the impact of an aggressive environment. Undoubtedly, polymer fibres are resistant to the majority of corrosive environments. Fibre-reinforced concretes are a frequently implemented construction solution. The possibility of concrete modification allows the emergence of new construction materials with improved physical-mechanical properties, under the condition of being applied relevantly.

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Impact Resistance of Post-Tensioned Concrete

MRS Proceedings ◽

10.1557/proc-211-149 ◽

1990 ◽

Vol 211 ◽

Author(s):

Nianzhi Wang ◽

Sidney Mindess

Keyword(s):

Reinforced Concrete ◽

Impact Loading ◽

Concrete Beams ◽

Impact Resistance ◽

Plain Concrete ◽

Reinforced Concrete Beams ◽

Fibre Reinforced Concrete ◽

Impact Tests ◽

The Impact ◽

Post Tensioned

AbstractImpact tests were carried out on post-tensioned beams, prepared both with plain concrete and fibre-reinforced concrete. It was found that post-tensioned beams might be less resistant to impact loading than were ordinary reinforced concrete beams. However, the addition of fibres to the concrete greatly increased the impact resistance of these beams.

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