Behavior Of High Performance Concrete Research Articles

Enhancing Mechanical Behaviour and Durability of High Performance Concrete with Silica Fume, Ground Blast Furnace Slag, and Marble Powder

Abstract This study investigates the impact of waste additives on the behaviour of high-performance concrete and its environmental implications, with a specific focus on resource conservation. The research objectives were realised through the preparation of high-performance concrete specimens incorporating industrial waste materials and marble powder as partial replacements for cement and fine aggregates, respectively. Silica fume and ground blast furnace slag were introduced as substitutes for 8% of the cement’s weight. Powdered marble was volumetrically substituted at levels of 5%, 10%, and 15% of the fine aggregates. The physical and mechanical properties of both fresh and cured concrete specimens were evaluated at different ages, encompassing parameters such as density, compressive strength, impulse velocity, water absorption, and durability. The findings demonstrated that high-performance concrete formulated with silica fume and ground blast furnace slag exhibited superior properties compared to compositions relying exclusively on Portland cement. Furthermore, the inclusion of marble powder as an alternative building material constituent in high-performance concrete resulted in increased efficiency and improved resistance against chemical acid attacks. Significantly, this approach contributes to reduce aggregate demands, environmental preservation, and the production of environmentally sustainable concrete.

Phase-field modeling of fracture in high performance concrete during low-cycle fatigue: Numerical calibration and experimental validation

The development of an elasto-plastic phase-field model is presented which is able to predict nonlinear behavior of high performance concrete (HPC) during low-cycle fatigue. An elasto-plastic damage model which follows the Drucker–Prager yield criterion is formulated. For the modeling of unsymmetric tension–compression behavior of HPC two different continuous stepwise linearly approximated degradation functions for HPC in tension and in compression are used. The experimental three-point bending tests at low-cycle using notched beams of pure HPC are performed. Load–CMOD (crack mouth opening displacement) curves are plotted using the measured experimental data and residual stiffness–CMOD curves are calculated using these experimental Load–CMOD curves. The data used for the interpolation of degradation functions are calibrated using the experimental results for three-point bending tests. For that purpose the uniaxial tension and uniaxial compression tests and three-point bending beam test for HPC are simulated numerically. The accuracy of the proposed numerical model using the presented integration algorithm is verified by comparing the degradation of stiffness in numerical and experimental results.

Assessment of Behaviour of High Performance Concrete on Incorporation of Waste Materials

Abstract: Disposal of wastes is one of the issues confronting the world today. Scientists all over the world are making efforts to minimize the production of wastes and to effectively recycle the waste. Reducing the green house gas emission and recycling of industrial wastes are the key areas of concern. Production of wealth will be a boon to the industries as the benefits are twofold: the pollution problem is addressed and the raw material shortage problem is also effectively tackled. Against this back-drop, in the present work, copper slag (CS) and Rice Husk Ash (RHA) is utilized as viable substitutes in concrete. M20 grade concrete with different mix proportion of sand replaced with copper slag from 0 to 70% and 0 to 25% cement replaced with Rice Husk Ash (RHA) and a combination of both (30% CS +10% RHA) is prepared. Tests for strength (compression and split tensile strength), acid resistance test and SEM analysis are carried out. The results of this work undertaken have revealed that peak strength is obtained on 30% replacement of sand with copper slag (45.3N/mm2) and 10% of cement with RHA (38.8N/mm2) and the combined mix gives good strength of 46.5N/mm.2 Keywords: Copper slag, Rice Husk Ash, Compression test, Acid resistance test, waste disposal

Influence of steel fibers on the fatigue behavior of high-performance concretes under cyclic loading

Due to the advancement of high-performance concretes, the development of filigree constructions has been improved in the last decades. However, as the demand to create more filigree designs increases, the vulnerability to fatigue loads of such structures has also become a decisive factor. Various construction projects, such as wide-span bridges or wind turbines, are exposed to fatigue loads. Especially wind turbines are permanently subjected to wind and wave loads of several hundred million load cycles during their service life. At present, the fatigue behavior of high-performance concretes under cyclic loading is still unknown. In a worst-case scenario, the significantly lower ductility can lead to a sudden failure of the entire structure. In this case, the addition of steel fibers could be advantageous, as they significantly improve the ductility of concretes. However, it is still undetermined how the material fatigue is influenced by steel fibers. Hence, systematic investigations on the fatigue behavior of various high-strength concretes with steel fibers were conducted. Since the crack-bridging effect of fibers is relevant for tensile stresses, predominantly cyclic bending tests were performed on concrete beams with different steel fiber variations. To accomplish the investigations, a test setup has been developed which allows the simultaneous testing of a total of six specimens. Based on the predetermined static concrete strengths, the specimens were subjected to cyclic loads with a defined lower stress level and various upper stress levels. During these cyclic tests, the cycles-to-failure as well as the degradation within the microstructure were detected.

Mechanical Properties of High-Performance Hybrid Fibre-Reinforced Concrete at Elevated Temperatures

Deterioration of concrete’s integrity under elevated temperature requires an alteration in its composition to have better thermal stability. Fibre-reinforced concrete has shown significant improvements in concrete strength and this paper aimed to investigate the influence of steel (ST) and polypropylene (PP) fibres on the behaviour of high-performance concrete (HPC) exposed to elevated temperatures. Six mixtures were prepared and cast by adding one or two types of polypropylene fibre (54 and 9 mm) at 0.25 or 0.5% and either singly or in a hybrid combination, along with a fixed volumetric content at 1% of five-dimensional hooked steel (5DH) fibres. At the age of 28 days, samples were heated to the targeted temperature of 800 °C and cooled down naturally to the laboratory temperature. Visual inspection, flexural, split tensile and compressive strengths were examined before and after the exposure to elevated temperatures. Results exhibited that the hybridization of long and short PP fibres, along with the ST fibres, has notably improved all residual mechanical properties of HPC and kept the integrity of concrete after exposure to elevated temperatures. In addition, PP fibres can significantly prevent spalling, but ST fibres were ineffective in mitigating explosive spalling in beams specimens.

Macroscopic model for steel fiber reinforced high performance concrete based on unit cell calculations

AbstractThe influence of reinforced steel fiber on the failure behavior of high performance concrete (HPC) is mainly characterized by the complex fiber‐matrix interaction at microscale. A phenomenological material model is developed for more efficient simulation of the overall material behavior of fiber reinforced HPC. For the calibration of the material parameters and to verify the efficiency of the presented phenomenological material model the simulation results of a virtual experiment using an ellipsoidal RVE and a macroscopic boundary value problem (BVP) are compared.

Effect of partial replacement of Eco sand on high performance concrete

The concrete plays a vibrant role in infrastructural developments. The major dispute of environmental degradation with sources of river sand is been substituted by M sand substantially at faster rate. The efforts to minimize the usage of Portland cement in concrete by other supplementary cementitious materials are also forging to control the environment-related problems. The study involves the behaviour of high performance concrete using partial replacement of cement by silica fume and partial replacement of M sand by Eco sand for M60 grade of concrete. Eco sand is an industrial waste product obtained from the cement industry is utilized as per the gradation analysis to evolve a better waste utilization and management system. The experimental works were conducted to evaluate the mechanical properties of high performance concrete containing cementitious materials of silica fume replaced by cement with 1-5%, M sand replaced by Eco-sand of 15-20%. Super plasticizer also added of about 1% to improve the workability of concrete. The results shows that the compressive strength gradually increased with 25% replacement of Eco sand and the optimal percentage of silica fume replacement identified as 5% by weight. The flexural strength at 28 days shows better for 20% replacement of eco sand than the control mix.

A Study on Strength Behavior of High Performance Concrete

High Performance Concrete can be seen of as a natural progression from Cement Concrete, where the elements are balanced and chosen to effectively contribute to the many features of Cement Concrete in both the fresh and hardened phases. One of High Performance Concrete's characteristics that offers important structural advantages is higher strength. Concrete, steel reinforcement, and formwork make up the three main expenses for a structural member. This study compares these important elements when higher-grade concrete is used in the design, with the goal of demonstrating that high strength concrete offers the most cost-effective solution for designing load-bearing members and for carrying a vertical load to the building foundation through columns. The water-cementitious material ratio, total cementitious material, cement-admixture ratio, and amount of super plasticizer dosage are the mix design elements that have the greatest impact on concrete strength. To create a higher-grade concrete mix, these variables need to be examined.

Behaviour of High Performance Concrete with Multi Compound Composite Cement

This study investigates about the behaviour of high performance concrete produced with multi component composite cements. Here, the cement is partially replaced with certain mineral admixtures. The mineral admixture used in the study are fly ash, rice husk ash, silica fume and ground granulated blast furnace slag in various percentages up to 50%. The mix proportion for fly ash and rice husk ash are kept constant thought the study as 25% and 7.5% respectively. The Mechanical properties such as (Compressive strength, split tensile strength, flexural strength and modulus of elasticity), Durability tests (Acid test, Sorptivity), permeability test and Non Destructive test are performed on M40 grade concrete cube material property, cylinder and prism. The outcomes were analyzed with the controlled mix. The results shown that the M3 mix ( 50% cement, 25% fly ash, 7.5% RHA,7.5 % silica fume and 10 % GGBS) obtained optimum strength, durability and other properties when analyzed with the other mixes.

Effect of Lightweight Aggregates on early-age behavior of High Performance Concrete

Laboratory experiments were conducted to investigate the effects of locally available natural lightweight aggregates (LWA’s) on volume changes and mechanical properties of highperformance concrete (HPC). The normal aggregates fraction of high-performance concrete was replaced with fine and coarse LWA’s at three different replacement levels, 5%, 10% and 20% by volume. The test results indicated a significant reduction in the autogenous shrinkage of highperformance concrete at 56 days without a corresponding considerable reduction in compressive strength of the same concretes. The test results have also shown that up to 20% volume fraction of coarse LWA’s could be used for mitigating the volume changes of HPC with a slight reduction in compressive and splitting tensile strengths, and elastic modulus. Therefore, this investigation recommends the use of locally available natural LWA’s as a viable curing technique for minimizing the volume changes and risk of cracking of HPC’s without compromising their mechanical properties.

Effect of internal curing on behavior of high performance concrete: An overview

This study reviews research experiences on developing an internal curing approach for high-performance concrete (HPC). Common materials have been used to produce the internal curing required to reduce self-desiccation in cement paste and will subsequently reduce the risks of developing cracks in hardened concrete. Furthermore, this study focuses on the behavior of HPC, including density, strength (compressive, splitting tensile, and flexural), shrinkage (autogenous and drying), and microstructure of hydrated cement paste. Results indicate that internal curing is more effective at a later age on splitting tensile and flexural strength than on compressive strength. Internal curing has enabled the interfacial transition zone increasingly compact and dense, thereby enhancing strength.

Early age tensile creep of high performance concrete containing mineral admixtures: Experiments and modeling

In the paper, the early age tensile creep behavior of high performance concrete (HPC) containing mineral admixtures was experimentally investigated. The results showed that, when the loading age was at 1 d and 2 d, the addition of fly ash (FA) increased the early age specific tensile creep of HPC, while blast furnace slag (BFS) showed an opposite effect. When the loading age was later than 3 d, the early age specific tensile creep of HPC was not obviously influenced by FA and BFS. Based on the experimental results, a rheology-based model (named as “ZC”, initials for the word “Self-developed” in Chinese) was proposed to predict the early age tensile creep of HPC with mineral admixtures. The ZC model was validated with other experimental results, and the prediction results agreed well with the experimental data. Moreover, the limitations and further improvements on the proposed model were also discussed in the paper.

Ductility of high-performance concrete and very-high-performance concrete elements with Ni-Ti reinforcements

This article presents an experimental study on the behavior of high performance concrete (HPC) and very high performance concrete (VHPC) concrete columns with Nickel-Titanium (Ni-Ti) shape memory alloy (SMA) reinforcements in critical regions subjected to constant axial and lateral cyclic load combinations. These materials make the cast-in-place of concrete easier by reducing the amount of transverse reinforcement, improving performance, attenuating damage in critical regions, minimizing residual deformations and reducing repair costs in structures located in seismic areas. Seven experimental tests were carried out to analyze the behavior of this element type. A nonlinear static cyclic pushover analysis was performed with finite element software (OpenSees), whose results were compared with the experimental results. This analysis allowed a parametric analysis to be run to extrapolate the experimental results. Strength capacity was approximately 41.8% greater in absolute terms in the specimens manufactured with VHPC and 6.2% greater in adimensional terms in those manufactured with HPC. Displacement ductility was 34.0% higher in the HPC specimens, and lowered with relative normal force and with transverse reinforcement separation. A residual drift ratio below 0.70% was generally observed when specimens reached 20% strength capacity loss. The residual drift ratio increased as a result of progressive concrete cover degradation, especially in the specimens manufactured with HPC.

Experimental study of the dynamic behaviour of High Performance Concrete (HPC) under tensile loading

This paper presents the measurement results of the dynamic tensile strength of a High Performance Concrete (HPC) obtained using full-field identification method. An ultra-high speed imaging system and the virtual fields method were used to obtain this information. Furthermore the measurement results were compared with the local point-wise measurement to validate the data pressing. The obtained spall strength was found to be consistently 20% lower than the one obtained when the Novikov formula is used.

Behaviour of high-performance concrete at high temperatures: some highlights

High-performance concrete (HPC) is one of the most recent types of concrete among the materials used routinely in building and civil structures. Their development in structures applications and the growing need for the justification of their fire resistance has led several laboratories to carry out research on their properties at high temperature. This letter presents some main aspects related to their physicochemical changes, thermal properties and mechanical properties at high temperature. It introduces a State of The Art prepared by the RILEM Technical Committee 227-HPB (Physical properties and behaviour of High-Performance Concrete at high temperature) and untitled “Behaviour of High-Performance Concrete at high temperatures”. This State of the Art will be publish in a next future.

Combined effect of silica fume and additive on the behavior of high performance concretes subjected to high temperatures

Combined effect of silica fume and additive on the behavior of high performance concretes subjected to high temperatures

Shrinkage and cracking behavior of high performance concretes containing chemical admixtures

Modern concretes often incorporate several chemical admixtures to alter the properties of fresh or hardened concrete. In this work, the influences of three types of chemical admixtures; calcium nitrite inhibitor (CNI), retarder (D − 17) and superplasticizer (W − 19) on free shrinkage and restrained shrinkage cracking of high performance concrete were experimentally investigated. The test results showed that, with the same water to binder ratio (0.4), mixtures containing D − 17 of 0.25 percent or higher ratio of W − 19 (2.76 percent) all exhibited a reduction in free shrinkage and shrinkage cracking width. However, the incorporations of various ratios of CNI into mixtures led to an increase in free shrinkage and shrinkage cracking width as compared to control mixture. In order to study the influence of CNI, the microstructure of concrete mixture containing CNI were investigated by Mercury Intrusion Porosimetry as well as Scanning Electronic Microscopy (SEM) technique.

Evaluation of high-performance concrete with recycled aggregates: Use of densified silica fume as cement replacement

This paper intends to evaluate the real influence of a commercial densified silica fume (SF) and of recycled concrete aggregates (RA) on the behaviour of high-performance concrete (HPC). For that purpose, three families of concrete with 0%, 5% and 10% silica fume (SF) of the binder’s mass were produced. In addition to the commercial silica fume, fly ash (FA) and superplasticizer (SP) were also incorporated in the concrete mixes. Each type of concrete comprises a reference concrete (RC) and three recycled aggregates concrete (RAC) mixes with replacement percentages (in volume) of fine natural aggregates (FNA) with fine recycled aggregates (FRA) and of coarse natural aggregates (CNA) with coarse recycled aggregates (CRA) of 50/50, 0/100 and 100/100, respectively. Considering the mechanical performance and durability of the concrete mixes, results show that it is possible to incorporate significant amounts of FRA and CRA. Regarding the silica fume, the densification process used in its manufacture seems to lead to the formation of agglomerates that change the real particle size of the SF, originating a loss of performance of the concrete made with them.

Carbonation Mechanism and Behavior of High Performance Concrete

The mechanism and behavior of concrete carbonation have been researched in this study. Effects of cement quantity, water to binder ratio (w/b) and content of fly ash on carbonation reaction were investigated. Morphology, microhardness and carbonation depth were analyzed. Experimental results show that high quantity of cement, low w/b ratio and small addition of fly ash are beneficial to improve the anti-carbonation of concrete.

Long term basic creep behavior of high performance concrete: data and modelling

This paper presents long term creep data from high performance concretes (HPC) sourced from different research programs or civil engineering projects carried out at IFSTTAR’s Paris laboratory, France. The authors are now making all this data publicly available through a data archive. The experimental procedures are described in detail, in particular that used to verify the constancy over time of the specimens’ compressive stress. It is shown that the majority of the concretes exhibit linear long-term behavior when plotted against log (time). Indeed, the paper describes modelling sourced from the literature, based on a logarithmic function of time which, despite its simplicity, matches the experimental data quite well. Using this modelling, we studied the behavior of HPC prepared from the same set of constituents. We have shown that the logarithmic change in creep is a quasi linear function of the water to cement ratio and aggregate concentration. Finally, the accuracy of the fib MC2010 model code has been tested on IFSTARR’s data bank.