scholarly journals Electrical Resistivity of Steel Fibre-Reinforced Concrete—Influencing Parameters

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3408
Author(s):  
Simon Cleven ◽  
Michael Raupach ◽  
Thomas Matschei
Keyword(s):  
Electrical Resistivity ◽  
Literature Review ◽  
Steel Fibre ◽  
Plain Concrete ◽  
Fibre Content ◽  
Fibre Reinforcement ◽  
Concrete Composition ◽  
Steel Fibre Reinforced Concrete ◽  
Granulated Blast Furnace Slag ◽  
The Impact

This paper presents a systematic study of the electrical resistivity of different steel fibre-reinforced concretes with fibre contents from 0 kg/m3 to 80 kg/m3 in order to identify possible effects of interactions among concrete composition and fibre type and content regarding electrical resistivity. Based on a literature review, four parameters, w/c ratio, binder content, ground granulated blast-furnace slag (GGBS) and fineness of cement, which show a significant influence on the electrical resistivity of plain concrete, were identified, and their influence on the electrical resistivity as well as interaction effects were investigated. The results of the experiments highlight that the addition of fibres leads to a significant decrease in electrical resistivity, independent of all additional parameters of the concrete composition. Additionally, it was shown that a higher porosity of the concrete, e.g., due to a higher w/c ratio, also results in a lower electrical resistivity. These results are in agreement with the literature review on plain concrete, while the influence of the concrete composition on the electrical resistivity is weaker with the increase in fibre content. The influence of fibre reinforcement is thus not affected by changes in the concrete composition. In general, a higher fibre dosage leads to a decrease in electrical resistivity, but the impact on the electrical resistivity varies slightly with different types of steel fibres. Based on this study, the potential of determining the fibre content using electrical resistivity measurements could be clearly presented.

scholarly journals A New Method to Determine the Steel Fibre Content of Existing Structures—Test Setup and Numerical Simulation

2022 ◽  
Vol 12 (2) ◽  
pp. 561
Author(s):  
Simon Cleven ◽  
Michael Raupach ◽  
Thomas Matschei
Keyword(s):  
Steel Fibre ◽  
Fibre Content ◽  
Fibre Reinforced Concrete ◽  
Missing Information ◽  
Concrete Composition ◽  
Test Setup ◽  
Steel Fibre Reinforced Concrete ◽  
Additional Information ◽  
Existing Structures ◽  
Laboratory Investigations

The diagnostics of constructions built with steel fibre reinforced concrete are extremely difficult to conduct because, typically, no information on the actual amount and orientation of the fibres is available. Therefore, it is of great interest to engineers to have the possibility to determine the steel fibre content and, at best, also the orientation of the fibres in existing structures. For this purpose, an easy-to-use test setup was developed and tested, in the course of laboratory investigations. This method can be used for cylinders, for example drilling cores, that can later be taken of existing structures, to determine both the fibre content and orientation. Based on these results, a model for cylindrical specimens was derived, which can be used for varying concrete compositions with steel fibre contents of up to 80 kg/m3. In the case of missing information concerning the concrete composition, it allows an initial estimation for the fibre content. In case additional information about the concrete composition is available, a much higher accuracy of the projected steel fibre content and therefore, an assessment of the building’s condition is possible.

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

2014 ◽  
Vol 626 ◽  
pp. 311-316 ◽  
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.

Structural performance of steel fibre reinforced concrete — Part IV. Toughness properties

2014 ◽  
Vol 5 (2) ◽  
pp. 119-125
Author(s):  
I. Kovács
Keyword(s):  
Reinforced Concrete ◽  
Steel Fibre ◽  
Fibre Orientation ◽  
Reinforced Concrete Beams ◽  
Fibre Reinforcement ◽  
Fibre Reinforced Concrete ◽  
Flexural Toughness ◽  
Steel Fibre Reinforced Concrete ◽  
Set Up ◽  
Flexural Tests

The present paper of a series deals with the experimental characterisation of flexural toughness properties of structural concrete containing different volume of hooked-end steel fibre reinforcement (75 kg/m3, 150 kg/m3). Third-point flexural tests were carried out on steel fibre reinforced concrete beams having a cross-section of 80 mm × 85 mm with the span of 765 mm, hence the shear span to depth ratio was 3. Beams were sawn out of steel fibre reinforced slab elements (see Part I) in order to take into consideration the introduced privilege fibre orientation (I and II) and the position of the beam (Ba-a, Ba-b, Ba-c) before sawing (see Part I). Flexural toughness properties were determined considering different standard specifications, namely the method of the ASTM (American Standards for Testing Materials), the process of the JSCE (Japan Society of Civil Engineering), and the final proposal of Banthia and Trottier for the post cracking strength. Consequently, behaviour of steel fibre reinforced concrete was examined in bending taking into consideration different experimental parameters such as fibre content, concrete mix proportions, fibre orientation, positions of test specimens in the formwork, while experimental constants were the size of specimens, the type of fibre used and the test set-up and test arrangement.

Bending Strength of Steel Fibre Reinforced Concrete Ribbed Slab Panel

2018 ◽  
Vol 15 (1) ◽  
pp. 15
Author(s):  
AMIR SYAFIQ SAMSUDIN ◽  
MOHD HISBANY MOHD HASHIM ◽  
SITI HAWA HAMZAH ◽  
AFIDAH ABU BAKAR
Keyword(s):  
Reinforced Concrete ◽  
Bending Strength ◽  
Steel Fibre ◽  
Concrete Slab ◽  
Future Application ◽  
Fibre Reinforcement ◽  
Fibre Reinforced Concrete ◽  
Conventional Concrete ◽  
Steel Fibre Reinforced Concrete ◽  
Bending Load

Nowadays, demands in the application of fibre in concrete increase gradually as an engineering material. Rapid cost increment of material causes the increase in demand of new technology that provides safe, efficient and economical design for the present and future application. The introduction of ribbed slab reduces concrete materials and thus the cost, but the strength of the structure also reduces due to the reducing of material. Steel fibre reinforced concrete (SFRC) has the ability to maintain a part of its tensile strength prior to crack in order to resist more loading compared to conventional concrete. Meanwhile, the ribbed slab can help in material reduction. This research investigated on the bending strength of 2-ribbed and 3-ribbed concrete slab with steel fibre reinforcement under static loading with a span of 1500 mm and 1000 mm x 75 mm in cross section. An amount of 40 kg/m steel fibre of all total concrete volume was used as reinforcement instead of conventional bars with concrete grade 30 N/mm2. The slab was tested under three-point bending. Load versus deflection curve was plotted to illustrate the result and to compare the deflection between control and ribbed slab. This research shows that SFRC Ribbed Slab capable to withstand the same amount of load as normal slab structure, although the concrete volume reduces up to 20%.

Observations on the electrical resistivity of steel fibre reinforced concrete

2013 ◽  
Vol 47 (1-2) ◽  
pp. 335-350 ◽  
Author(s):  
Anders Ole Stubbe Solgaard ◽  
Mette Geiker ◽  
Carola Edvardsen ◽  
André Küter
Keyword(s):  
Electrical Resistivity ◽  
Reinforced Concrete ◽  
Steel Fibre ◽  
Fibre Reinforced Concrete ◽  
Steel Fibre Reinforced Concrete

The Influence of Different Fibres Ratio in the Cementitious Composite on Ballistic Resistance

2018 ◽  
Vol 760 ◽  
pp. 114-118
Author(s):  
Jindřich Fornůsek ◽  
Michal Mára ◽  
Romana Lovichová
Keyword(s):  
Steel Fibre ◽  
Fibre Reinforcement ◽  
Local Damage ◽  
Cementitious Composite ◽  
High Quality ◽  
Ballistic Resistance ◽  
Extreme Load ◽  
The Individual ◽  
Different Content ◽  
The Impact

The aim of this work was to determine the resistance of cementitious composite to extreme load due to the different content of steel fibres. Extreme load was caused by the impact of the projectile. Resistance was evaluated on the basis of experimental research, where local damage was investigated on samples of ultrahigh performance concrete with a dispersed steel fibre reinforcement caused by a projectile impact. The projectiles were deformable and non-deformable with a calibre of 7.62x39 and 5.56x45 mm. The projectiles in the experiment hit the centre of the sample, or to specify the classification to the left or right side of the sample. The recording of the results served to evaluate the resistance of the individual samples to the local damage. The output of this paper is to find the optimal amount of fibre in ultra-high quality concrete with respect to its ballistic resistance.

Structural performance of steel fibre reinforced concrete — Part I. Overview of the experimental program

2014 ◽  
Vol 5 (1) ◽  
pp. 9-19
Author(s):  
I. Kovács
Keyword(s):  
Reinforced Concrete ◽  
Steel Fibre ◽  
Concrete Beams ◽  
Test Methods ◽  
Reinforced Concrete Beams ◽  
Shear Behaviour ◽  
Structural Performance ◽  
Fibre Reinforcement ◽  
Fibre Reinforced Concrete ◽  
Steel Fibre Reinforced Concrete

Abstract The papers of the series deal with experimental characterisation of mechanical as well as structural properties of different steel fibre reinforced concretes that can be used for several structural applications. An extensive experimental programme (six years) has been developed to investigate the effect of steel fibre reinforcement on the mechanical performance and structural behaviour of concrete specimens. Specimens and test methods were selected to be able to detect realistic behaviour of the material, representing clear effect on the structural performance. Material compositions, test methods, type of test specimens will be detailed in the presented paper (Part I). Furthermore, compressive strength (Part II), stress-strain relationship (Part II), splitting strength (Part III) and toughness (Part IV) will also be discussed. In the light of the motivation to determine the structural performances of 1D concrete structural element affected by steel fibre reinforcement, bending and shear behaviour (Part V) as well as serviceability state (Part VI) of steel fibre reinforced concrete beams will be analysed. Since normal force — prestressing force — can affectively be used to improve the structural performances of RC element flexural tests were carried out on prestressed pretensioned steel fibre reinforced concrete beams (Part VII). Moreover, focusing on the in-plane state of stresses for 2D structures, behaviour of steel fibre reinforced concrete deep beams in shear and steel fibre reinforced concrete slabs (Part VIII) in bending will be explained. Finally, based on the wide range of the experimental and analytical studies on the presented field, a new material model for the 1D uniaxial behaviour (Part IX) and its possible extension to the 3D case (Part X) will be described hereafter. All papers will put emphasis on the short literature review of the last four decades.

Sign in / Sign up

Export Citation Format

Share Document