An integrated approach for modelling the tensile behaviour of steel fibre reinforced self-compacting concrete (original) (raw)
Related papers
2012
This paper presents numerical and experimental results of the behavior of Steel Fibre Reinforced Self-Compacting Concrete (SFRSCC). The main objective of the research is the study of the SFRSCC mechanical behavior including the post-peak softening response. An experimental program has been developed to evaluate the influence of aggregate size, granulometry, compressive and tensile strength, steel fibre type and the fibre amount in SFRSCC structural behavior. Three point bending notched tests as well as compression and splitting tension tests have been performed to evaluate the SFRSCC properties. Eight mix proportions have been designed and used in order to achieve nominal compressive strengths of 30 and 50 MPa. The mixtures were composed with two maximum size of crushed limestone, of 12 and 20 mm; fibres with aspect ratio (length/diameter) (lf/df); lf/df > 65 or lf/df < 65; and amount of steel fibres of 40 kg/m 3 and 70 kg/m 3 . The experimental results are represented by load...
Steel Fiber-Reinforced Self-Compacting Concrete: Experimental Research and Numerical Simulation
Journal of Structural Engineering, 2008
Over the last few decades, the astonishing developments of super plasticizers technology allowed great achievements on the conception of concrete mixes exhibiting self-compacting ability. Since the eighties, some methodologies have been proposed to achieve self-compacting requirements in fresh concrete mixes, based on the evaluation of the flowing properties of these mixes. There still persist, however, some doubts about the most appropriate strategy to define the optimum composition of a self-compacting concrete (SCC) mix, based on a required performance. The behavior of SCC as a structural material can be improved if adequate steel fiber reinforcement is added to SCC mix composition. In fact, the fiber reinforcement mechanisms can convert the brittle behavior of this cement based material into a pseudo-ductile behavior up to a crack width that is acceptable under the structural design point-of-view. Fiber addition, however, increases the complexity of the mix design process, due to the strong perturbation effect that steel fibers cause on fresh concrete flow. In the present work, a mix design method is proposed to develop cost effective and high performance Steel Fiber Reinforced Self-Compacting Concrete (SFRSCC). The material properties of the developed SFRSCC are assessed as well as its potentiality as a structural material, carrying out punching and flexural tests on panel prototypes. A material nonlinear analysis is carried out, aiming to address the possibility of calibrating the constitutive model parameters by obtaining, with an inverse analysis, the fracture parameters using forcedeflection relationships recorded in simpler laboratory tests, like the three point notched beam bending test. The contribution of steel fibers for punching resistance is also, by this means, discussed.
Tensile Behavior of Steel Fiber-Reinforced Self-Compacting Concrete
SP-274: Fiber Reinforced Self-Consolidating Concrete: Research and Applications, 2010
The tensile behavior of a self-compacting concrete (SCC) reinforced with two hooked ends steel fiber contents was assessed in this paper by performing stable displacement control tension tests. Based on the stress-displacement curves obtained, the stress-crack width relationships were derived, as well as the energy dissipated up to distinct crack width limits and residual strengths. The number of effective fibers bridging the fracture surface was determined and was compared with the theoretical number of fibers, as well as with the stress at crack initiation, residual stresses and energy dissipation parameters. In general, a linear trend between the number of effective fibers and both the stress and energy dissipation parameters was obtained. A numerical model supported on the finite element method was developed in this paper. In this model, the fiber reinforced concrete is assumed as a two phase material: plain concrete and fibers randomly distributed. The plain concrete phase was ...
ANALYTICAL MODELLING ON THE BEHAVIOR OF STEEL FIBRE REINFORCED SCC UNDER AXIAL COMPRESSION
Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. The crack propagation can be reduced by addition of steel fibres in concrete. Addition of fibres reduces workability of concrete which is the major drawback. SFRSCC is a trending concrete where the required workability is obtained by addition of chemical admixtures such as Super plasticizer (SP) and Viscosity Modifying Agent (VMA). In the present work, an effort is made to make a comparative study of stress-strain behavior of M30 grade steel fiber Reinforced Self-Compacting Concrete (SFRSCC). Complete Stress – Strain behavior has been presented and an empirical equation based on mathematical model is proposed to predict the stress – strain behavior of such concrete under compression. The proposed mathematical equation shows good correlation with the experimental results. There is an improvement in the Axial Compressive Strength of SCC which could be due to the addition of the steel fibers
Bond characteristics of steel fibre reinforced self-compacting concrete
Canadian Journal of Civil Engineering, 2012
Steel fibre reinforced self-compacting concrete (SFRSCC) is a relatively new composite material that combines the benefits of the self-compacting concrete (SCC) technology with the advantages derived from the fibre addition to a brittle cementitious matrix. Steel fibres improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibres on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fibre and SCC. Based on the available experimental results, the current analytical steel fibre pullout model is modified by considering the different SCC properties and different fibre types (smooth, hooked) and fibre inclination. To take into account the effect of fibre inclination in the pullout model, apparent shear strengths (t(app)) and slip coefficient (b) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle (f).
Prediction of Theoretical Shear Strength of Steel Fibre Reinforced Self-Compacting Concrete
2019
Of all the different kinds of failures in concrete, shear failure is a sudden and brittle and occurs abruptly without any prior warning. To avoid these types of failures in concrete, beams are traditionally reinforced with stirrups at closer spacing based on design. The present study is aimed at studying the shear behaviour of steel fibre reinforced selfcompacting concrete and predicting a theoretical equation for evaluating the shear strength. In the experimental study, two grades of self-compacting concrete (SCC30 and SCC70) were considered. A total of 16 shear deficient beams were cast and tested for two shear span to depth ratios (a/d) of 2 and 3 for both without and with steel fibres. By analysing the cracked portion of the beam an equation to predict the theoretical shear strength was proposed. The comparison between experimental shear strength and theoretical shear strength was found to be in good agreement with a percentage error in all the cases is less than 15% and also ra...
Many studies have been conducted in past decades in order to promote the application of steel fibre reinforced concrete (SFRC), either traditional or self-compacting. However, just a few of them focus on explaining the differences in the behaviour and the properties of these two types of concrete. The objective of this paper is to analyse such differences in terms of flexural behaviour, fibre content and orientation. For that, an extensive experimental programme was conducted. In total 3 mixes of self-compacting and 3 mixes with traditional concrete were produced with the nominal fibre contents of 30kg/m 3 , 45kg/m 3 and 60kg/m 3. In each case, specimens were cast and characterized with the Bending Test (code EN 14651) and the Inductive test. The results show how fibre orientation justifies the differences in the mechanical behaviour of the materials and the scatter of the results.
Mechanical Properties of Steel Fiber Reinforced Self-Compacting Concrete
International journal of engineering technologies, 2018
In this study, steel fiber reinforced self-compacting concrete (SFR-SCC) specimens were examined by considering the effects of different parameters on the material performance and to promote the use of fiber materials in building industry. Use of steel fibers in SCC is still limited due to lack of required codes and standards in this field. More research is required to understand the effects of steel fibers on mechanical properties of the concrete. For this purpose, 5 mixes; control and reinforced with 2 different fiber volumes and two different fiber types; were produced. Compressive strength, splitting tensile strength and 3-point notched bending tests were carried out on these specimens for thoroughly evaluating mechanical performance of steel fiber reinforced self-compacting concretes. Keywords Steel fiber reinforced self-compacting concrete, flexural toughness, ductility, three point notched bending, flexural strength.