Development Of High Performance Concrete Research Articles

Optimizing concrete performance with polymer-cement networks: enhanced flexural strength and crack resistance

Concrete is a building material known for its high compressive strength but susceptibility to cracking. Once concrete cracks, moisture, aggressive ions, and air can easily penetrate its body, deteriorating its mechanical properties and durability. Herein, polyacrylamide (PAM) is incorporated into the concrete via in situ polymerization of acrylamide (AM) to construct a polymer-cement network, aiming to improve flexural strength and crack resistance. Incoporating 7% AM, the initial cracking fracture toughness is increased by 47.5%. Concrete with 10% AM exhibits a 28-day flexural strength of 19.38MPa, 65.5% higher than normal concrete. The polymer network formed by in situ polymerization of AM crosslinks with cement hydrates to construct the polymer-cement network, which is responsible for the improvement of flexural strength and crack resistance. Upon completion of the polymerization reaction, the aggregate and the cement matrix are bridged by polymer, concomitant with the densification of the interfacial transition zone (ITZ). In situ polymerization of AM is found to be more efficient and effective than directly adding PAM in improving flexural strength. Moreover, refinement of the pore structure is also observed by in situ polymerization of AM. In conclusion, our study presents a convenient and efficient approach to improving the crack resistance of concrete, thereby spurring the development of high performance concrete.

Development of sustainable HPC using rubber powder and waste wire: carbon footprint analysis, mechanical and microstructural properties

This research advances the development of eco-friendly high-performance concrete (HPC) by integrating tire rubber powder and waste wire, focusing on both enhanced mechanical properties and reduced environmental impact. Substituting up to 40% of silica sand with rubber powder helps maintain the compressive strength necessary for high-strength concrete applications. The addition of waste wire is designed to improve ductility. A comprehensive evaluation includes mechanical and microstructural analyses, such as compressive, splitting tensile, and flexural strength assessments, in addition to Scanning Electron Microscopy (SEM) and Differential Thermal Analysis (DTA). Environmental implications are assessed by measuring the embodied carbon footprint. Findings indicate that the absence of rubber powder allows for a compressive strength peak of 95 MPa, while 50% rubber content leads to a decrease to 25 MPa, establishing a 40% rubber threshold for optimal strength. Conversely, 3% waste wire reinforcement enhances the strength to 106 MPa. Microstructural investigations reveal that increased rubber content adversely affects compressive strength by weakening the cement matrix, and reducing calcium-silicate-hydrate (C-S-H) formation. Significantly, the study reveals that replacing silica sand with rubber powder, along with waste wire reinforcement, substantially reduces the carbon footprint of the material, contributing to more sustainable construction methodologies.

Prediction on partial replacement of cement and coarse aggregate by zeolite powder and steel slag in high-performance concrete

High performance concrete is obtained by the inclusion of mineral admixtures like silica fume and fly ash in the concrete. The research explores the viability and performance of sustainable concrete by introducing zeolite powder as a partial substitute for cement and steel slag as a partial replacement for coarse aggregate in M-70 grade concrete. Zeolite powder, possessing pozzolanic properties, is a natural or synthetic aluminosilicate material, while steel slag is an industrial byproduct with potential as an alternative aggregate source. The main objective is to investigate the impact of zeolite powder and steel slag on the development of High-Performance Concrete (M-70) in accordance with Bureau of Indian standards. The formulation of high-performance concrete involved replacing 12.5%, 15%, and 17.5% of the cement with zeolite powder and varying the proportion of steel slag as a replacement for coarse aggregate (ranging from 30% to 55%). A comprehensive mechanical test was conducted on these specimens and compared with conventional concrete. Among the 19 mixes, the optimal combination was identified, incorporating 15% zeolite powder as a cement replacement and 45% steel slag as a coarse aggregate replacement, resulting in superior performance compared to conventional concrete. This mix was further studied for non-destructive testing, and microstructural analysis. Subsequently, the experimental results were compared with predicted outcomes using the Taguchi method. The close alignment between the values obtained experimentally and those predicted further validates the effectiveness of the optimized mix.

An Evaluative Review of Recycled Waste Material Utilization in High-Performance Concrete

The disposal of waste materials and their adverse effects on the environment have become a worldwide concern, disturbing the fragile ecological equilibrium. With growing awareness of sustainability in the construction industry, it is of great importance to recycle waste materials for producing high-performance concrete (HPC). This aligns with the twelfth Sustainable Development Goal (SDG) of the United Nations, emphasizing responsible production and consumption, especially concerning the production of HPC using waste materials and energy-efficient methods. The review evaluates the purposeful utilization of recycled waste materials to improve the engineering characteristics of HPC, taking into consideration pertinent literature. It encompasses a comparative evaluation of strength development, water absorption, microstructures, and x-ray diffraction (XRD) analyses of HPC manufactured with different types of recycled waste materials. The key result of the review showed that using incinerated bottom ash (IBA) below 25% and incorporating 40% copper slag can enhance HPC’s mechanical performance. Additionally, recycled coarse aggregate (RCA) can replace up to 50% of conventional aggregate in self-compacting HPC with minimal impact on durability properties. In HPC cement substitution research, fly ash, silica fume, and metakaolin are prominent due to their availability, with fly ash showing remarkable durability when used as a 15% cement replacement. This thorough review offers valuable insights for optimizing the utilization of recycled waste materials in the development of environmentally friendly HPC. Doi: 10.28991/CEJ-2023-09-11-020 Full Text: PDF

Effect of Dispersing Carbon Nanotube in Aqueous Solution by Poly-Carboxylic-Based Surfactants on Mechanical and Microstructural Properties as Cementitious Composites.

The development of high-performance concrete using carbon nanotubes (CNTs), which is used in various industries owing to its excellent mechanical properties, has attracted much attention, leading to ongoing research in this area. However, when mixing CNTs into cement paste, there has been limited focus on the dispersibility, and, in most cases, aqueous dispersions of CNTs used in other industrial sectors are used. Because CNTs form the structures of bundles or aggregates owing to their high aspect ratio and van der Waals force between particles, the desired dispersibility cannot be obtained when mixing CNTs in powder form with other materials. Therefore, in this study, we examined the applicability of CNT aqueous dispersions using PC-based plasticizer used in concrete. Aqueous dispersions of CNT using PC-based surfactants are prepared and their properties are compared with those of a PVP-based aqueous dispersion. To analyze the mechanical properties, the compressive strength and flexural strength are measured on the 28th day. Then, the dispersibility and microstructure are analyzed using scanning electron microscopy image analysis, thermogravimetric analysis, and BET (Brunauer-Emmett-Teller) analysis. The analysis results show the enhancement of mechanical properties due to the mixing of the CNT dispersion, and the results confirm the applicability of the proposed CNT aqueous dispersions using PC-based surfactants.

Development and Performance Evaluation of UHPC and HPC Using Eco-Friendly Additions as Substitute Cementitious Materials with Low Cost

Ultra-high-performance concrete (UHPC) and high-performance concrete (HPC) are widely used in construction engineering applications. The quality and economy of this type of concrete are the main challenges in real construction systems due to their expensive cost. In the present investigation, the performances of UHPC and HPC were improved using eco-friendly additives from natural sources or industrial wastes. Accordingly, different kinds of concrete mixtures were prepared with the addition of various eco-friendly materials, such as metakaolin (10, 15, and 20%), silica fume (2.5, 5, 10, and 15%), cement kiln dust (CKD) (0, 5, and 10%), and 1 vol.% of steel and polypropylene fibers. All of these materials were subjected to efficient treatment and purification processes. The results indicated that the prepared UHPC was characterized by high compression and flexural strengths. The prepared UHPC (sample CR-2) with metakaolin (10%), CKD (10%), and 1 vol.% of steel fibers provided the highest compressive strength of 135 MPa at 28 days. Moreover, the results showed that reducing the cement amounts to 750, 500, and 250 kg/m3 provided concrete with efficient structural requirements and specifications and can be characterized as UHPC and HPC. Also, the mixture (sample CM15) with a metakaolin addition of 15%, CKD of 100 kg/m3, and 1 vol.% of steel fibers showed the highest flexural strength of 19.14 MPa at 28 d. Moreover, the highest splitting tensile strength of the prepared UHPC cylinders was 9.6 MPa at 28 d for the MSS1000 sample, which consisted of 15% metakaolin, a cement content of 1000 kg/m3, silica fume of 10%, and steel fibers of 1% vol. The prepared UHPC mixtures will reduce the amount of consumed cement and the production cost, with a high performance in comparison to classical concrete. Finally, it was clear that the prepared UHPC and HPC concrete with green additions can serve efficiently in specific construction applications, with high performance, economic feasibility, and safe environmental impacts.

The Effect Of Curing Types On Compressive Strength Of High Performance Concrete

The present investigation considers the effect of curing temperatures (30, 40, and 50˚C) and curing compound method on compressive strength development of high performance concrete, and compares the results with concrete cured at standard conditions and curing temperature (21˚C). The experimental results showed that at early ages, the rate of strength development at high curing temperature is greater than at lower curing temperature, the maximum increasing percentage in compressive strength is 10.83% at 50C˚ compared with 21C˚ in 7days curing age. However, at later ages, the strength achieved at higher curing temperature has been less, and the maximum percentage of reduction has been 5.70% at curing temperature 50C˚ compared with 21C˚curing temperature in 91 days curing age. Also, the results showed that the specimens which are cured under field condition (using curing compound) have a various strength development rate, and the results indicate 92.11% as minimum field-standard curing strength ratio.

A novel development of HPC without cement: Mechanical properties and sustainability evaluation

In the current study, a new type of high-performance concrete (HPC) called HPC-CAS (calcium oxide-activated slag) is presented. The HPC-CAS is made from calcium oxide-activated slag and is reinforced with steel, basalt, and recycled polyethylene terephthalate (PET) fibers to make it less brittle. To assess the mechanical properties of the samples, five mix designs were produced, including HPC, HPC-CAS without reinforcement, and HPC-CAS reinforced with fibers. Compressive, splitting tensile, and flexural strengths were then determined. In addition, the study evaluated the environmental impact of different mix designs using two methods: IMPACT 2002+ and CML baseline 2000. The findings indicate that in HPC-CAS, calcium oxide serves as the activator for slag, resulting in a compressive strength of 105 MPa, which is only 4.54% lower than that of HPC. Notably, incorporating steel and recycled PET fibers addresses the issue of brittle fracture in HPC and HPC-CAS samples, leading to compressive strengths of 121 MPa and 78 MPa, respectively. When compared to samples without fibers, the inclusion of steel, basalt, and recycled PET fibers in HPC-CAS resulted in improved splitting tensile strengths of 159%, 89%, and 55%, respectively. The samples containing steel, basalt, and recycled PET fibers also revealed flexural strengths with 3.68 and 1.20 times, and 31% increase, respectively, as compared to those without fibers. Overall, the incorporation of fibers significantly enhanced the brittle behavior of the HPC-CAS geopolymer matrix. However, it is important to note that the addition of 3% fibers to HPC-CAS resulted in higher environmental impacts in all categories as compared to HPC-CAS without fibers. Furthermore, the embodied carbon footprint associated with the production of HPC-CAS was found to be significantly lower, with a reduction of approximately 61%. Furthermore, when comparing HPC-CAS to HPC, it is evident that HPC-CAS exhibits decreased adverse effects on human health, ecosystem quality, and resource utilization.

Influence of hybrid coir-steel fibres on the mechanical behaviour of high-performance concrete: Step towards a novel and eco-friendly hybrid-fibre reinforced concrete

In this study, an effort has been extended to analyse the properties of high-performance concrete (HPC) reinforced with hybrid combinations of coconut fibre (CF) (at 0.1, 0.2, and 0.3% volume fractions) and steel fibre (SF) (at 0.5 and 1% volume fractions). The compressive strength, load–deflection behaviour, and splitting tensile strength of fibre-reinforced HPC were evaluated. Moreover, ultrasonic pulse velocity and water absorption characteristics were also examined. The results revealed that the hybridization of CF and SF notably increased the mechanical strength and flexural behavior of HPC. A maximum increase in the compressive strength of HPC was noticed with the hybridization of 0.1–0.3 vol% of CF and 0.5 vol% SF. However, the tensile and flexural strength of HPC increased proportionally with the increase in CF and SF content. The use of 0.1–0.2 vol% CF by volume fraction is recommended for optimum mechanical performance without compromising the quality and permeability-resistance of plain and SF-reinforced HPC. This study provides insight into the development of eco-friendly and cheap hybrid fibre-reinforced HPC using CF.

Development of high-performance concrete using ultrafine flyash

Increasing urbanization and industrialization demands advanced infrastructure over the existing structure, especially in a developing country (like India) where the population is very large and keeps on increasing. To deal with this complex situation there is an essential need for structures that have higher strength along with sustainability in design. The current project deals with the development of high performance concrete using ultrafine flyash. The project aims to develop high strength concrete of M-60 grade with binary blending of cement with ultrafine flyash and ternary blending of cement with ultrafine flyash and silica fume to produce precast concrete of M-50 grade. Further, the desirable percentage of ultrafine flyash in the development of high-strength concrete of M-60 grade and desirable percentages of both ultrafine flyash and silica fume in precast concrete of M-50 grade was found out to achieve the desired target strength according to the Indian standard criteria. Workability and compressive strength tests were performed on all the mixes. Results reveal that 5% replacement of cement by ultrafine flyash is the most desirable amount which can satisfy the criteria according to various Indian standard codes. Further, other strengths and durability tests were performed on desired concrete. The results show that desired concrete satisfies all the criteria and used in the development of the metro structure.

Experimental study on physical and mechanical properties and micro mechanism of carbon nanotubes cement-based composites

Carbon nanotubes are considered as a promising material for the development of high performance concrete. In order to study the effects of Multi walled carbon nanotubes (MWCNTs) content, water cement ratio and addition method on the mechanical properties and microstructure of cement-based composites, specimens with MWCNTs content of 0%, 0.05%, 0.08%, 0.10%, 0.15%, 0.20%, and 0.30% were prepared when the water cement ratio was 0.25, 0.3, 0.35, and 0.4, respectively. The physical properties, mechanical properties and microstructure were tested. The test results show that with the increase of MWCNTs content, the flexural strength and compressive strength of cement-based composites increase first and then decrease. The DIC test shows that the displacement and strain of the specimen with MWCNTs are smaller than the blank sample under the same concentrated load, while it is opposite before the failure of sample. The SEM test shows that MWCNTs play the role of bridging and filling in the matrix. The EDS analysis results show that the five main elements of carbon, oxygen, aluminum, silicon, and calcium in the composite are evenly distributed in the cement matrix.

A Critical Review on Effect of Nanomaterials on Workability and Mechanical Properties of High-Performance Concrete

The application of nanomaterials in high-performance concrete (HPC) has been extensively studied worldwide due to their large surface areas, small particle sizes, filling effects, and macroquantum tunneling effects. The addition of nanomaterials in HPC has great contribution to enhancing the pore size of the cementitious matrix, improving the hydration of cement, and making the matrix much denser. In order to present an exhaustive insight into the feasibility of HPC reinforced with nanomaterials, the new development of HPC was summarized and the influence of different nanomaterials on the properties of HPC was reviewed based on more than 100 recent studies in this literature review. Workability, compressive strength, tensile strength, and flexural strength properties of HPC with nanomaterials were discussed in detail. In addition, nanomaterial-modified HPC was compared with the traditional concrete and obtained a lot of valuable results. The results in the present review indicate that the addition of various nanomaterials improves the mechanical properties of HPC, while reducing the workability of HPC. However, there is an optimal dosage of nanomaterial for improving the mechanical properties of HPC. Improving the properties of HPC by adding nanomaterials is expected to become a mainstream technique in the future. This literature review can provide comprehensive and systematic knowledge to researchers and engineers working on HPC and promote the application of this new HPC in modern civil engineering.

SIFCON-A High Performance Concrete - Experimental Investigations

This paper addresses the development of High Performance Concrete in the past along with the experimental work on properties of Slurry Infiltrated Fibrous Concrete (SIFCON). Slurry infiltrated fibrous concrete has high strength, large ductility and good performance under seismic excitations. There is an increase in numbers of structures testified by the recent symposiums and conferences held on HPFRC. Now presently investigations are being carried out to suggest recommendations for the design of HPFRC structures. SIFCON consist of cement slurry and different types of steel fibers. It is observed that with the increase in percentage of steel fibers there is an improved static, dynamic and mechanical properties of concrete. Steel fibers also act as crack arrester and improve durability. In the present study, it is observed that at 9% fiber content the compressive strength, split tensile strength and flexural strength is optimum.

A study on compatibility of superplasticizers with high strength blended cement paste

Adoption of High-Performance Concrete (HPC) made with low water to binder ratios in practical applications are being encouraged widely for enhanced development of high early strength and durability. The type of superplasticizers incorporated, highly influences the development of HPC. At low water-cement ratio, HPC is made workable by the incorporation of superplasticizers. The wrong proportion of cement and admixture in a mix causes low fluidity, rapid/delayed setting, segregation, bleeding etc. Therefore, it is important to underline the interaction mechanism between cement and superplasticizer for the better utilization of concrete. As more blended cements are used now a day, it is imperative to investigate the compatibility of superplasticizers in such paste systems. In this study, the saturation dosages and compatibility of sulphonated naphthalene formaldehyde (SNF) and poly carboxylate ether (PCE) superplasticizers with cement paste prepared from Ordinary Portland Cement (OPC) 53 grade, Portland Pozzolana Cement (PPC) and Slag cement (PSC) for different water-binder (w/b) ratios are analysed using the marsh cone test and mini slump test. As per the result obtained, PSC was found to have higher saturation dosages than OPC and PPC. The optimum dosages for PCE admixture are lower than that for SNF as their mechanism of action are different.

Development of high performance concrete using industrial waste materials and nano-silica

There is a concerted effort worldwide to use environment-friendly binders in the establishment of civil infrastructure. The use of such materials, as a partial or total replacement of Portland cement, leads to technical, economic and environmental benefits. The reported study was conducted to develop high performance concrete (HPC) utilizing two industrial waste materials (IWMs), namely cement kiln dust (CKD) and electric arc furnace dust (EAFD), in conjunction with nano-silica (NS). The mechanical properties, morphology and durability characteristics of the developed HPC were evaluated. The strength of concrete decreased with increasing quantity of both CKD and EAFD that were used as a partial replacement of cement. However, an increase in strength was noted due to the incorporation of NS. The chloride permeability significantly decreased due to the incorporation of 5% NS in CKD and EAFD cement concretes. A dense and uniform microstructure, with a compact interfacial transition zone, was noted in concrete specimens incorporating Portland cement, IWMs and NS. The incorporation of IWMs along with NS results in the following benefits: environmental (decreased greenhouse gas emission and solution of the disposal problem associated with the IWMs), economic (decreased overall cost of concrete) and technical (enhanced service life of structures).

Effect of Partial Substitution of Fine Aggregate with Copper Slag on Mechanical and Durability of High Performance Concrete-A Review

The challenge before the construction industry is to meet the demand of the efficient and economically viable construction materials posed by the huge infrastructural needs. Many nations are observing an expeditious growth in the field of construction necessitating the utilization of natural reserves for the expansion of infrastructure. This expansion is giving a warning to available reserves of nature. The natural ingredients, fine aggregates and coarse aggregate constitute more than 70% volume of the concrete. The availability of these resources is decreasing at a very high pace. In fact due to the severe problem with the availability of natural sand, the construction industry is faced with the pressing need to consider available options to lessen the reliance on natural aggregates. Copper slag being a waste material, can be used as an option for fine aggregates. The substitution of fine aggregate from nature with waste materials from industries such as copper slag offers economic and technical dominance, which are of pronounced significance in the present scenario. This study is, based on the critical review of the development of High Performance Concrete (HPC) by replacing fine aggregate with copper slag by observing various other researches and reviews. The key intent of this paper is to closely look at the copper slag utility as an unconventional material to be used as a substitute of fine aggregate and its effect on mechanical and durability parameters of HPC.

Evaluation of the Thermal and Shrinkage Stresses in Restrained High-Performance Concrete.

The early age volume deformation is the main course for the cracking of high-performance concrete (HPC). Hence, the shrinkage behavior and the restrained stress development of HPC under different restraints and curing conditions were experimentally studied in this paper. The method to separate the stress components in the total restraint stress was proposed. The total restrained stress was separated into autogenous shrinkage stress, drying shrinkage stress and thermal stress. The results showed that the developments of the free shrinkage (autogenous shrinkage and drying shrinkage) and the restrained stress were accelerated when the drying began; but the age when the drying began did not significantly influence the long-term shrinkage and restrained stress of HPC; the autogenous shrinkage stress continuously contributed to the development of the total restrained stress in HPC; the drying shrinkage stress developed very rapidly soon after the drying began; and the thermal stress was generated when the temperature dropped. The thermal stress was predominant at the early age, but the contributions of the three stresses to the total restrained stress were almost the same at the age of 56 d in this study.

An experimental investigation on properties of concrete by using silica fume and glass fibre as admixture

Abstract High Performance Concrete (HPC) has been used in various structures all over the world since last two decades. Recently a few infrastructure projects have also seen specific application of high-performance concrete. The development of High Performance Concrete (HPC) has brought about the essential need for additives both chemical and mineral to improve the performance of concrete. Most of the developments across the work have been supported by continuous improvement of these admixtures. To attain the set out objectives of the present investigation, cement has been replaced partially with silica fume 20%. Glass fibres 1% to produce High Performance Concrete. Hence, an attempt has been made in the present investigation to study the behaviour of Natural sand and M-sand. Natural Sand has been replaced with M-sand in three different percentages viz. 0, 50, 100%. HPC is tested for compression strength.

Development of High Performance Concrete

Development of High Performance Concrete

Early-age residual stress and stress relaxation of high-performance concrete containing fly ash

High-performance concrete (HPC) is widely used. However, HPC with a low water-to-binder ratio generally experiences rather high autogenous shrinkage. If restrained, autogenous shrinkage can result in the development of residual tensile stresses that may be sufficient to cause cracking at an early age. Fly ash (FA) has been utilised as a mineral admixture to reduce shrinkage and improve the durability of HPC. Although shrinkage development and early-age cracking resistance of HPC under restraint have been investigated, research on the stress relaxation of HPC with FA by ring tests is limited. Restrained ring tests on the cracking resistance of HPC using FA as 0, 20, 35 and 50% by weight replacements of cement were conducted. The test results showed that: free shrinkage decreased with an increase in FA replacement ratio; the actual strain in the steel ring decreased with increasing FA replacement; the residual stress of the concrete ring decreased with increasing FA replacement; the ratio of maximum residual stress to time-dependent splitting tensile strength decreased with an increase in FA replacement; the relaxed stress was almost constant when the FA replacement ratio increased from 0 to 20%, and decreased when the FA replacement ratio increased from 20% to 35% and 50%; and the cracking potential based on stress rate decreased when the FA replacement ratio increased from 0 to 20% and 35%, and increased when the FA replacement ratio increased from 35% to 50%.