Journal articles: 'High strength concrete'

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Salas-Montoya, Andrés, and Beatriz E. Mira-Rada. "Evaluation of key aggregate parameters on the properties of ordinary and high strength concretes." VITRUVIO - International Journal of Architectural Technology and Sustainability 8 (May 11, 2023): 76–85. http://dx.doi.org/10.4995/vitruvio-ijats.2023.19596.

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This paper reports the results of a study conducted to determine the influence of coarse aggregate type on the workability, compressive strength, and flexural strength of normal and high strength concretes with target 28-day compressive strengths of 30 and 60 MPa and two water/cement ratios of 0.44 and 0.27. The concretes were prepared using four types of natural coarse aggregates, namely diabase, calcareous, river gravel, and basalt, with maximum particle sizes of 12.7 and 19.1 millimeters. Silica fume was added to the high-strength concretes at a replacement ratio to Portland cement of 10% by mass. The results showed that among all aggregates, basaltic aggregate with a maximum particle size of 12.7 millimeters produced concrete with the highest compressive and flexural strength, followed by limestone and river aggregate, indicating that particle size, surface texture, structure and mineralogical composition play a dominant role in the behavior of concretes, especially high strength concretes. Normal strength concretes showed similar compressive strengths, while the concrete containing limestone gave slightly higher strength. These results show that for a given water/cementitious material ratio, the influence of the type of coarse aggregate on the compressive strength of the concrete is more important for high strength concrete than for normal strength concrete.

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Salas-Montoya, Andrés, and Beatriz E. Mira-Rada. "Evaluation of key aggregate parameters on the properties of ordinary and high strength concretes." VITRUVIO - International Journal of Architectural Technology and Sustainability 8 (May 11, 2023): 76–85. http://dx.doi.org/10.4995/vitruvioijats.2023.19596.

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This paper reports the results of a study conducted to determine the influence of coarse aggregate type on the workability, compressive strength, and flexural strength of normal and high strength concretes with target 28-day compressive strengths of 30 and 60 MPa and two water/cement ratios of 0.44 and 0.27. The concretes were prepared using four types of natural coarse aggregates, namely diabase, calcareous, river gravel, and basalt, with maximum particle sizes of 12.7 and 19.1 millimeters. Silica fume was added to the high-strength concretes at a replacement ratio to Portland cement of 10% by mass. The results showed that among all aggregates, basaltic aggregate with a maximum particle size of 12.7 millimeters produced concrete with the highest compressive and flexural strength, followed by limestone and river aggregate, indicating that particle size, surface texture, structure and mineralogical composition play a dominant role in the behavior of concretes, especially high strength concretes. Normal strength concretes showed similar compressive strengths, while the concrete containing limestone gave slightly higher strength. These results show that for a given water/cementitious material ratio, the influence of the type of coarse aggregate on the compressive strength of the concrete is more important for high strength concrete than for normal strength concrete.

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Dr., Udeme Hanson Iron. "Flexural Strength Models for Normal Laterised and High Strength Laterised Concretes at Optimum Mix Proportions." Flexural Strength Models for Normal Laterised and High Strength Laterised Concretes at Optimum Mix Proportions 05, no. 07 (July 21, 2022): 1767–84. https://doi.org/10.5281/zenodo.6880694.

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This study develops mathematical models for obtaining optimum flexural strengths of normal laterised(NLC) and high strength laterised concretes (HSLC). The models can be expressly used to evaluate the indirect tensile strengths of both types of concretes without going through the traditional methods of mix design. Optimum mixing ratios and optimum flexural strengths predicted are also supplied by the models. The three point load method was adopted for testing for the flexural strengths. Laterite, has been widely used to partially or wholly replace sand in concrete with resultant low strengths. The production of HSLC using superplasticiser was achieved in this study. Scheffe’s simplex theory based on (5, 2) simplex lattice (for NLC) and (6, 2) simplex lattice (for HSLC) was used to optimize the mix proportions for the flexural strengths of each respective laterised concrete. Conplast SP 430 superplasticiser (a sulphonated naphthalene formaldehyde admixture) was used to obtain the high strength laterised concrete. Mathematical models were developed for the mix proportioning of the laterised concretes and all strengths predicted by the models agreed with their corresponding experimentally observed values. Using the model, the optimum flexural strength and the corresponding mix proportions for the targeted strength of laterised concrete could be easily evaluated with the help of the written Q-BASIC computer programme.

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Vasudha, Dattani. "Strength Development of High Strength Concrete using Rice Husk Ash." Journal of Advances in Civil Engineering and Management 6, no. 1 (February 22, 2023): 10–13. https://doi.org/10.5281/zenodo.7663976.

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<em>With a high water to cement ratio and poor workability, traditional concrete is one type of uneconomical concrete that is challenging to install and prone to issues like honeycomb and bleeding. Concretes with great workability and durability, including self-compacting concrete (SCC), have recently been created and used to address these issues. Self-Compacting Concrete (SCC) is a unique variety of concrete that has excellent self-compacting abilities and can fill formwork and spaces between reinforcing bars with its own weight without the need of vibrating compaction. To create self-compacting concrete, a variety of components are employed, including rice husk ash, metakaolin, silica fume, and steatite powder. To obtain high strength and lower the amount of cement in the concrete, this substance is most frequently substituted for cement in the market. The current study focuses on using rice husk ash powder in high strength concrete at various percentages. The impact of rice husk powder on the characteristics of high strength concrete with various cement percentages by weight was investigated via a number of trials.</em>  

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Vincent, Thomas, and Togay Ozbakkloglu. "An Experimental Study on the Compressive Behavior of CFRP-Confined High- and Ultra High-Strength Concrete." Advanced Materials Research 671-674 (March 2013): 1860–64. http://dx.doi.org/10.4028/www.scientific.net/amr.671-674.1860.

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It is well established that external confinement of concrete with fiber reinforced polymer (FRP) sheets results in significant improvements on the axial compressive behavior of concrete. This understanding has led to a large number of experimental studies being conducted over the last two decades. However, the majority of these studies have focused on normal strength concretes (NSC) with compressive strengths lower than 55 MPa, and studies on higher strength concretes have been very limited. This paper presents the results of an experimental study on the compressive behavior of FRP confined high- and ultra high-strength concrete (HSC and UHSC) with average compressive strengths of 65 and 100 MPa. A total of 29 specimens were tested under axial compression to investigate the influence of key parameters such as concrete strength and method of confinement. All specimens were cylindrical, confined with carbon FRP and were 305 mm in height and 152 mm in diameter. Results obtained from the laboratory testing were graphically presented in the form of axial stress-strain relationships and key experimental outcomes are discussed. The results of this experimental study indicate that above a certain confinement threshold, FRP-confined HSC and UHSC exhibit highly ductile behavior. The results also indicate that FRP-wrapped specimens perform similar to concrete-filled FRP tube (CFFT) specimens at ultimate condition, however notable differences are evident at the transition region when comparing stress-strain curves.

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Ekolu, Stephen O., and Sheena Murugan. "Durability Index Performance of High Strength Concretes Made Based on Different Standard Portland Cements." Advances in Materials Science and Engineering 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/410909.

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A consortium of three durability index test methods consisting of oxygen permeability, sorptivity and chloride conductivity were used to evaluate the potential influence of four (4) common SANS 10197 cements on strength and durability of concrete. Twenty four (24) concrete mixtures of water-cement ratios (w/c's) = 0.4, 0.5, 0.65 were cast using the cement types CEM I 42.5N, CEM II/A-M (V-L) 42.5N, CEM IV/B 32.5R and CEM II/A-V 52.5N. The concretes investigated fall in the range of normal strength, medium strength and high strength concretes. It was found that the marked differences in oxygen permeability and sorptivity results observed at normal and medium strengths tended to vanish at high concrete strengths. Also, the durability effects attributed to use of different cement types appear to diminish at high strengths. Cements of low strength and/or that contained no extenders (CEM 32.5R, CEM I 42.5N) showed greater sensitivity to sorptivity, relative to other cement types. Results also show that while concrete resistance to chlorides generally improves with increase in strength, adequately high chloride resistance may not be achieved based on high strength alone, and appropriate incorporation of extenders may be necessary.

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Bílek, Vlastimil, Vladimíra Tomalová, Petr Hájek, and Ctislav Fiala. "Evolution from High Strength Concrete to High Performance Concrete." Key Engineering Materials 629-630 (October 2014): 49–54. http://dx.doi.org/10.4028/www.scientific.net/kem.629-630.49.

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High strength concrete for the production of concrete railway sleepers was designed more than 20 years ago. The compressive strength of the concrete was very high from the start, but flexure strengths showed some irregular development - a decrease in time. Later, also a significant decrease of fracture properties was recorded. Microcracking was found to be the reason for this; therefore some modifications were performed to avoid this happening (especially the reduction of the maximum size of aggregates from 22 mm to 16 mm or 11 mm). Some problems concerning frost resistance of the concrete with a slag addition were reduced by applying ternary binders. All of the results are discussed from the point of view of a long-term observation of the strengths and fracture properties ́ development during the time period of 5 years or even more.

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Skalny, J., and L. R. Roberts. "High-Strength Concrete." Annual Review of Materials Science 17, no. 1 (August 1987): 35–56. http://dx.doi.org/10.1146/annurev.ms.17.080187.000343.

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Sivaganesh Raja, Budda, Velagala L D Prasad, and Gopu Ganesh Naidu. "Estimation of Shear Strength of High Strength Hybrid Fiber Reinforced Concrete." International Journal of Scientific Engineering and Research 4, no. 2 (February 27, 2016): 25–31. https://doi.org/10.70729/ijser15676.

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Tolstoy, A. "FINE-GRAINED HIGH-STRENGTH CONCRETE." Construction Materials and Products 3, no. 1 (July 8, 2020): 39–43. http://dx.doi.org/10.34031/2618-7183-2020-3-1-39-43.

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the article discusses the possibilities of improving the strength characteristics of fine-grained concrete. Modification of compositions and production technology of fine-grained high-strength concrete is possible with the use of natural and man-made raw materials of various chemical and mineral composition. It is shown that it is possible to increase the economic feasibility of high-strength fine-grained concretes with the preservation of performance characteristics due to the use of man-made raw materials and production waste. The issues of controlling the processes of structure formation and identifying a potentially stable state of hardening compositions are considered, possibly on the basis of modification and design methods for the composition of construction objects with improved properties.

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El Mir, Abdulkader, Salem Georges Nehme, and Kinga Nehme. "In situ application of high and ultra high strength concrete." Epitoanyag - Journal of Silicate Based and Composite Materials 68, no. 1 (2016): 20–23. http://dx.doi.org/10.14382/epitoanyag-jsbcm.2016.4.

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12

Lahoud, Antoine E. "Slenderness effects in high-strength concrete columns." Canadian Journal of Civil Engineering 18, no. 5 (October 1, 1991): 765–71. http://dx.doi.org/10.1139/l91-093.

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High-strength concretes are being increasingly used in the columns of high-rise buildings. Analytical studies of the slenderness effects in these columns have been very limited. The behavior of slender columns with normal- and high-strength concretes is studied using a finite element program. Differences and similarities in long-term and short-term behaviors between high-strength and normal-strength slender concrete columns are noted and discussed. Key words: columns, slenderness, high-strength concrete, creep, finite elements.

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Ekolu, Stephen O., Zaid Mohamed, and Sean Kay. "Experimental Investigation and Yield Line Prediction for Ultimate Capacity of Recycled Aggregate Concrete Slabs." International Journal of Engineering Research in Africa 47 (March 2020): 31–44. http://dx.doi.org/10.4028/www.scientific.net/jera.47.31.

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The present investigation was conducted to evaluate the influence of recycled aggregates on structural behaviour of reinforced concrete (RC) slabs. Concrete mixtures of 0.6 and 0.4 water/cement ratios were used to produce normal strength concretes and high strength concretes, respectively. Various concrete mixtures were prepared by replacing 19 mm natural coarse aggregates with 0, 25, 50, 100% recycled coarse aggregate (RCA) then used to cast RC slabs of size 500 x 300 x 100 mm thick, and 100 mm cubes. The two-way concrete slabs were reinforced orthotropically with Y12 steel bars. Workability, compressive strength, and split tensile strength properties of concrete were measured, while the RC slabs were subjected to monotonic loading until failure. The experimental results obtained were compared with theoretical failure loads predicted using the yield line theory. It was found that the use of RCA in concrete generally leads to reduction of workability and concrete strength in proportion with the RCA content incorporated into the mixture. The yield line method gave a conservative and accurate theoretical prediction of the actual ultimate loads for control concretes, predicting 10% lower values, but it exhibited loss of prediction accuracy for RCA concretes of normal strengths basically overestimating their failure loads. Accordingly, it would be unsafe to employ the yield line method for design of RCA concrete slabs of normal strengths. Generally, the adverse effects of RCA on concrete properties and structural behaviour can be mitigated significantly by adjusting mixture designs to higher strengths or by employing high strength concretes

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14

MUGURUMA, Hiroshi. "High strength and ultra-high strength concrete." Journal of the Society of Materials Science, Japan 38, no. 431 (1989): 875–85. http://dx.doi.org/10.2472/jsms.38.875.

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15

Bazhenov, Yu M., S.-A. Yu Murtazaev, D. K.-S. Bataev, A. H. Alaskhanov, T. S. A. Murtazaeva, and M. S. Saydumov. "High-strength concretes based on anthropogenic raw materials for earthquake resistant high-rise construction." Engineering Solid Mechanics 9, no. 3 (2021): 335–46. http://dx.doi.org/10.5267/j.esm.2021.1.004.

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This work is devoted to development of optimum recipes of high-strength concretes based on filled binders with fine-milled anthropogenic mineral filler intended for earthquake resistant high-rise monolithic construction. The optimum recipes of concretes in this work have been developed on the basis of computations and experimental designing of cast concrete mixes with chemical additives and anthropogenic mineral fillers, as well as destructive inspection methods as the most precise for analysis of physicomechanical and deformation properties of concrete. The following raw materials have been used for production of high-strength concretes: natural quartz sands with the fineness modulus F.M. = 1.7-1.8; crushed limestone with the particles sizes of 5-20 mm; water reducing chemical additives and hardening retarder to control specifications of concrete mixes; plain Portland cement, grade PTs 500 D0; anthropogenic mineral additives (fillers) in the form of crushed concrete and ceramic bricks. Optimum recipes of monolithic concretes have been designed using anthropogenic raw materials including normal concrete grades with compressive strength of M30-M40 and high-strength concrete grades of M50-M80, characterized by high homogeneity of cement stone with significantly finer pores and lower shrinkage. Herewith, it has been established that fine-milled anthropogenic mineral filler in the form of crushed concrete and ceramic bricks at the ratio of 70:30, respectively, efficiently influences specifications of concrete mixes on their basis significantly increasing resistance of the mix against sedimentation and water gain. It has been established that the developed high-strength concretes based on filled binders with fine-milled anthropogenic mineral filler are characterized by high freeze–thaw resistance (from F400 to F600) and water tightness (W14 and higher), which is a solid base providing high lifecycle of such concretes.

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Kuznetsova, I. S., and I. V. Zubova. "Effect of aggregate type on strength and deformation properties of high-strength concrete during heating." Bulletin of Science and Research Center of Construction 41, no. 2 (June 26, 2024): 118–30. http://dx.doi.org/10.37538/2224-9494-2024-2(41)-118-130.

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Introduction. High-strength concrete is widely used in contemporary construction. Expanded introduction of high-strength concrete necessitates the need for studying its behavior at high temperatures (in case of fire) in order to ensure the required fire resistance of load-bearing reinforced concrete structures made of high-strength concrete in terms of fire safety of buildings and structures.Aim. To determine the effect of aggregate types on strength and deformation characteristics of high-strength B100 concrete when heated to temperatures from 100 °C to 800 °C with a step of 100 °C.Materials and methods. Laboratory tests of prism strength and elastic modulus of basalt and granite high-strength concrete were carried out on prism samples in a heated state according to standard methods using special heating equipment combined with laboratory pressure equipment.Results. The authors determined structure behavior factors of basalt and granite high-strength concrete during heating, specifying the decrease in compressive strength and elastic modulus. Deformation diagrams during axial compression of high-strength granite and basalt concretes under heating were drawn.Conclusions. The dynamics of reduction in strength and deformation properties is similar for granite and basalt high-strength concrete under heating and is specific for silicate aggregate concretes. The elastic moduli of basalt high-strength concrete are higher than those of granite high-strength concrete, both at 20 °C and when heated, thereby determining the dependence of high-strength concrete deformation properties on the types of aggregates. Deformation diagrams during the axial compression of high-strength granite and basalt concretes showed specific character: unilinear – when heated to temperatures of about 300–400 °C, bilinear – at higher heating temperatures, therefore differing from traditional ideas and theoretical recommendations.

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Pereira Prado, Lisiane, Ricardo Carrazedo, and Mounir Khalil El Debs. "Interface strength of High-Strength concrete to Ultra-High-Performance concrete." Engineering Structures 252 (February 2022): 113591. http://dx.doi.org/10.1016/j.engstruct.2021.113591.

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V.Senthilkumar and N.Asvinth. "Study on Characteristics Compressive Strength of High Strength Concrete Using Silica Fume." Journal of Advanced Cement & Concrete Technology 3, no. 1 (February 10, 2020): 1–9. https://doi.org/10.5281/zenodo.3660994.

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The Strength and performance of concrete plays a vital for construction of heavy structures like bridges, power stations, tall buildings, etc. Concrete that meets special performance and uniformity requirements are produced by using different mix proportions, different curing practices, using different admixtures and by using low water cement ratio. These concretes contain new type of Superplastiser which responsible for obtaining high strength and high durability. In addition to High Performance Concrete which has become relatively common, some High Strength Concrete, which is of interest for the Indian market. For high strength concrete the characteristic compressive strength varies between 40MPa and 100MPa.The alternate materials available to increase the strength of concrete are silica fume, metakaolin, alccofine, Ground Granulated Blast furnace Slag (GGBS), etc. So in this study silica fume is partially replaced with 10%, 20% and 30% of cement with constant percentage of superplastiser as 1.5% and compression test is carried out.

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Adewuyi, Adekunle P., and Odette Animbom. "Performance-Based Evaluation of Steel Fibre Reinforced Normal- and High-Strength Concretes Using Statistical Analysis of Experimental Database." Journal of Civil Engineering and Urbanism 14, no. 3s (September 25, 2024): 238–46. https://doi.org/10.54203/jceu.2024.25.

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The widespread acceptance of concrete can be attributed to its unique characteristics, despite inherent drawbacks such as brittleness and weak tensile strength. The study was aimed at evaluating the optimal content and characterization of steel fibres required to impede crack propagation and enhance overall strength of concrete. The influence of critical factors like fibre content, length, diameter, and volume fraction on the performance of steel fibre reinforced concretes (SFRC) through statistical analysis of 209 experimental data. The influence of these factors on the compressive, flexural, and tensile strengths of concrete was analyzed as a function of the mean and coefficient of variation of the normalized strength values. The study found that steel fibres in concrete produced success rates of 67.9% (7.1% average strength improvement = ASI) in compressive strength, 78.5% (38.2% ASI) in flexural strength and 84.2% (23.8% ASI) in tensile strength. The study further separately examined the impact of steel fibres on both normal strength concretes (NSC) and high strength concretes (HSC). The findings indicated an overall success rate of 60% (6.97% ASI), 69.9% (38.36% ASI), and 75.6% (23.59% ASI) for compressive, flexural, and split tensile strength, respectively, in NSC. However, higher degree of strength enhancement of 74.0% (7.16% ASI), 84.8% (39.21% ASI), and 86.6% (23.51% ASI) were recorded for compressive, flexural, and split tensile strength, respectively in HSC. The research underscores the effectiveness of incorporating steel fibres as a reinforcement strategy in enhancing various strength aspects of concrete.

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Bezgodov, Igor, Simyon Kaprielov, and Andrey Sheynfeld. "RELATIONSHIP BETWEEN STRENGTH AND DEFORMATION CHARACTERISTICS OF HIGH-STRENGTH SELF-COMPACTING CON-CRETE." International Journal for Computational Civil and Structural Engineering 18, no. 2 (June 24, 2022): 175–83. http://dx.doi.org/10.22337/2587-9618-2022-18-2-175-183.

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he paper provides data on the strength and deformation characteristics of heavy self-compacting concrete of classes B30-B100 with a cubic compressive strength of 36.5-114.8 MPa. It has been established that the values of the concrete prism compressive strength (36.2-104.2 MPa) are 42-64% higher than the normalized values given in the building code of the Russian Federation SP 63.13330.2018. The values of the static modulus of elasticity for high-strength concretes of classes B80-B100 are 44.1-48.1 GPa and exceed by 5-12% the values given in SP 63.13330.2018. The ultimate compressive strains of concrete of classes B30-B100 are in the range from 261×10-5 to 326×10-5 and exceed the value of 200×10-5 given in SP 63.13330.2018. Complete deformation diagrams of self-compacting concretes of classes B30-B100 have been constructed. The nonlinearity of these ones decreases with increasing concrete strength. The descending branch of the σ-ε diagram is observed only for concrete of a class below B55 with a total relative compres-sive strain of 403.3 × 10-5 under a loading level of 0.85Rb. Concrete of classes B55-B100 has no descending branch. Previously established dependencies are refined for the analytical description of strains and stresses at any stages of loading structures.

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Zhou, Bai Rui, Dong Dong Han, Jian Hua Yang, Yi Liang Peng, and Guo Xin Li. "Effects of Two Polypropylene Fibers on the Properties of High Strength Concrete." Applied Mechanics and Materials 357-360 (August 2013): 1328–31. http://dx.doi.org/10.4028/www.scientific.net/amm.357-360.1328.

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Portland cement, crushed stone, sand and superplasticizer were used to obtain a high strength concrete with a low water to binder ratio. A reticular polypropylene fiber and a single polypropylene fiber were used to improve the strength of the high strength concrete, but the effects of the two fibers on the slump and strengths were quite different. The reasons of the differences were the surface area and the modulus of elasticity of the fibers. The results show the reticular fiber was better to used in high strength concretes.

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Marzouk, H. "Creep of high–strength concrete and normal–strength concrete." Magazine of Concrete Research 43, no. 155 (June 1991): 121–26. http://dx.doi.org/10.1680/macr.1991.43.155.121.

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Saeed, Jalal Ahmad, and Abbas Mohammed Abubaker. "Shear Strength and Behavior of High Strength Reinforced Concrete Beams without Stirrups." Sulaimani Journal for Engineering Sciences 3, no. 3 (April 1, 2016): 64–75. http://dx.doi.org/10.17656/sjes.10037.

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Saeed, S. A., and S. R. Sarhat. "Strength of fiber reinforced high-strength concrete with stirrups under direct shear." Journal of Zankoy Sulaimani - Part A 2, no. 2 (September 1, 1999): 64–73. http://dx.doi.org/10.17656/jzs.10040.

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Lee, Ming-Gin, Wei-Chien Wang, Yung-Chih Wang, Yi-Cheng Hsieh, and Yung-Chih Lin. "Mechanical Properties of High-Strength Pervious Concrete with Steel Fiber or Glass Fiber." Buildings 12, no. 5 (May 7, 2022): 620. http://dx.doi.org/10.3390/buildings12050620.

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Pervious concrete (also called porous concrete) is one of the most promising sustainable and green building materials today. This study examined high-strength pervious concrete and ordinary-strength pervious concrete reinforced with steel fiber or glass fiber. A total of fifteen mixtures of normal- and high-strength pervious concretes with steel fiber or glass fiber were used. The goal of high-strength pervious concrete is that the 28-day compressive strength be above 42 MPa and the porosity be as close to 15% as possible to achieve technical specifications. Both normal- and high-strength pervious concretes reinforced with steel fiber (1%, 2%) or glass fiber (0.25%, 0.5%) were investigated in water permeability, porosity, compressive strength, flexural strength, elastic modulus, and toughness tests. The test results show that in both high-strength pervious concrete and ordinary pervious concrete with steel fibers added, the porosity and permeability coefficient are increased compared with the control group. The coefficient of permeability for high-strength, fiber-reinforced pervious concretes with two aggregate sizes meets the requirements of the ACI specification for structural concrete. In addition, the high-strength pervious concrete specimen H1-S2 (2% steel fiber) has the highest compressive strength of 52.8 MPa at the age of 28 days. The flexural strength of pervious concrete also increases with age. However, the flexural strength of fiber-reinforced pervious concrete did not follow this trend due to the large variation in the quality control of different fiber mixtures. However, both steel fiber and glass fiber have a certain degree of improvement in the flexural toughness, and the effect is better with steel fiber. After the flexural strength reaches the peak value, there is still about 30% of the bearing capacity, and it gradually decreases until it is completely destroyed.

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Yedla, Venkatesh *. &. G. Kalyan. "AN EXPERIMENTAL STUDY ON STRENGTH AND PERMEABILITY PROPERTIES OF HIGH STRENGTH CONCRETE." INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY 6, no. 12 (December 15, 2017): 317–25. https://doi.org/10.5281/zenodo.1116722.

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Concrete is the most important engineering material and the addition of some other materials may change the properties of concrete. Mineral additions which are also known as mineral admixtures have been used with cements for many years. There are two types of materials crystalline and non crystalline. High performance concrete (HPC) exceeds the properties and constructability of normal concrete. Micro silica or silica fume is very fine non crystalline material. Silica fume is produced in electric arc furnace as a byproduct of the production of elemental silicon<strong>’</strong>s or alloys containing silicon. IT is usually a grey colored powder somewhat similar to Portland or some fly ashes silica fume is generally categorized as a supplementary cementious material In our experiment we are using micro silica as an artificial pozzolans. We are adding 0%, 5%, 10%, 15% and 20% by wt of cement in concrete. HPC are made with carefully selected high quality ingredients and optimized mixture designs. Super Plasticizers are usually used to make these concretes fluid and workable. HPC almost always has a higher strength than normal concrete

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Singh, Ramanpreet, Gurprit Singh Bath, and Manjeet Bansal. "Study of High Strength Concrete Using Microsilica." International Journal of Emerging Research in Management and Technology 6, no. 8 (June 25, 2018): 414. http://dx.doi.org/10.23956/ijermt.v6i8.174.

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The framework of bridges, buildings, roads etc. need concrete. The concrete which is being used is not able to fulfil the contemporaneous needs. In India High Strength Concrete (HSC) is preferred for manufacturing practices and at the same time High Performance Concrete is used at high level. The properties of HSC are improved like mechanical and durability are improved by using silica fume in concrete. HSC has made the work of construction company more rewarding to design tall, long and light structures. HSC is helpful in designing buildings with good number of floors, wide area bridges and slim structure. The products like fly-ash, copper slag, silica fume etc. are produced by industries which leads to various environmental problems. The experiment on silica was done which stated that no strength is lost in silica-fume concretes. The experiment comprises four levels of silica-fume at the rate of 0%, 5.5%, 8.0%,9.5% and 11.0% which results high strength concrete.

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Chen, Guo Can, Zhi Sheng Xu, and Wei Hong Tang. "Residual Strength of Super High Strength Concrete Used Stone-Chip after Exposure to High Temperatures." Advanced Materials Research 374-377 (October 2011): 2456–60. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.2456.

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This paper presents the results of experimental studies on the residual compressive strength of concrete produced with stone-chip as fine aggregates with the compressive strengths of unheated specimen ranging from 45.8 to 129.5MPa after exposure to high temperatures and the experimental parameters being the temperature, admixtures, and PP fiber. Specimens were heated in an electric furnace for 4h to high temperatures ranging from 150 to 960°C. Experimental results showed that the compressive strengths of super high strength concrete used stone-chip (abbreviated to SHSCUS) and normal strength concrete used stone-chip (abbreviated to NSCUS) after exposure to elevated temperatures changed in the manners different from that of normal strength concrete, which reached their peak at about 400°C, and the presence of pp ﬁbers in SHSCUS concrete could reduce the risk of spalling at the high temperatures and the peak value after fire.

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Solikin, Mochamad. "Compressive Strength Development of High Strength High Volume Fly Ash Concrete by Using Local Material." Materials Science Forum 872 (September 2016): 271–75. http://dx.doi.org/10.4028/www.scientific.net/msf.872.271.

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This paper presents a research to produce high strength concrete incorporated with fly ash as cement replacement up to 50% (high volume fly ash concrete) by using local material. The research is conducted by testing the strength development of high volume fly ash concrete at the age of 14 days, 28 days and 56 days. As a control mix, the compressive strength of Ordinary Portland Cement (OPC) concrete without fly ash is used. Both concrete mixtures use low w/c. consequently, they lead to the use of 1 % superplasticizer to reach sufficient workability in the process of casting. The specimens are concrete cubes with the dimension of 15 cm x15 cm x 15 cm. The totals of 24 cubes of HVFA concrete and OPC concrete are used as specimens of testing. The compressive strength design of concrete is 45 MPa and the slump design is ± 10 cm. The result shows that the compressive strengths of OPC concrete at the age of 14 days, 28 days, and 56 days are 38 MPa, 40 MPa, and 42 MPa. Whereas the compressive strength of HVFA concrete in the same age of immersing sequence are 29 MPa, 39 MPa, and 42 MPa. The result indicates that HVFA concrete can reach the similar compressive strength as that of normal concrete especially at the age of 56 days by deploying low water cement ratio.

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D, Zealakshmi, Ravichandran A, and Kothandaraman S K. "Strength Modeling of High Strength Concrete." IOSR Journal of Mechanical and Civil Engineering 11, no. 3 (2014): 57–61. http://dx.doi.org/10.9790/1684-11375761.

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Srinivasa Reddy, V., and R. Nirmala. "Development of quaternary blended high performance concrete made with high reactivity metakaolin." International Journal of Engineering & Technology 7, no. 2.1 (March 5, 2018): 79. http://dx.doi.org/10.14419/ijet.v7i2.1.11048.

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In the last three decades, supplementary cementitious materials such as fly ash, silica fume and ground granulated blast furnace slag have been judiciously utilized as cement replacement materials as these can significantly enhance the strength and durability characteristics of concrete in comparison with ordinary Portland cement (OPC) alone. Hence, high-performance concretes can be produced at lower water/powder ratios by incorporating these supplementary materials. One of the main objectives of the present research work was to investigate synergistic action of binary, ternary and quaternary blended high strength grade (M80) concretes on its compressive strength. For blended high strength grade (M80) concrete mixes the optimum combinations are: Binary blend (95%OPC +5% FA, 95%OPC +5% MS and 95%OPC +5%MK), ternary blend (65%OPC+20%FA+15%MS) and quaternary blend (50%OPC+28%FA+11%MS+11%MK). Use of metakaolin in fly ash based blended concretes enhances compressive strength significantly and found to be cost effective in terms of less cement usage, increased usage of fly ash and also plays a major role in early strength development of fly ash based blended concrete.

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Inozemtcev, A. S., and E. V. Korolev. "Model of high-strength lightweight concrete." Construction Materials, no. 12 (December 15, 2024): 34–41. https://doi.org/10.31659/0585-430x-2024-831-12-34-41.

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Modeling is a tool of scientific cognition that makes it possible, by replacing the object under study with its representation (model), to explore it and interpret the results on the object itself. Obviously, the material model should allow for the study of the influence of prescription factors on its properties (direct task) or, with established requirements for the material, determine the parameters of the model (values of factors) that ensure the achievement of established requirements (inverse task). In the course of the study, a compounding and structural model of high-strength lightweight concrete was developed, which is a system of equations that establish the relationship of structural parameters (geometric characteristics, compounding factors (component content) with the sedimentation rate and viscosity of the concrete mixture and the specific strength of concrete. The conducted modeling makes it possible to predict the properties of the concrete mixture and concrete on a hollow aggregate and establish boundary conditions to achieve the target values of key quality indicators. It has been established that an urgent task in the production of high-strength lightweight concretes is the development of compounding and technical solutions that provide a combination of high mobility and uniformity, which is explained by the value of I/C as a key control factor located in opposite optimization areas, and in order to achieve high specific strength of high-strength lightweight concrete, it is additionally necessary to regulate the adhesion of cement stone to a hollow filler.

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Davidyuk, Artem, and Igor Rumyantsev. "Quality control of high-performance concrete in high-rise construction during operation." MATEC Web of Conferences 170 (2018): 01035. http://dx.doi.org/10.1051/matecconf/201817001035.

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With onset of the XXI century, the demand for construction of high-rise buildings with the load-bearing framework made of high-performance cast-in-situ concrete has increased many-fold in the construction sector. Specific features of the high-performance concrete of bearing structures in the situation of real operation of high-rise buildings are continuously studied by scientists and specialists all over the world, and regulatory and methodological documents are being complemented and adjusted. High-performance concretes and structures made of them possess some specific features that should be taken into account in quality control. The methods of concrete inspection and concrete strength evaluation described in GOST 18105 “Concretes. Guidelines on Testing and Evaluation of Strength” and GOST 22690 “Concretes. Evaluation of Strength by Mechanic Non-Destructive Test Methods” were written when precast reinforced concrete was predominantly used in the construction sector and were limited to the functions of intra-factory quality control of reinforced concrete products. At present, instruments for non-destructive testing using indirect methods are usually calibrated with the help of local destructions, as a rule, a pull out or rib shear test. The said methods are in fact indirect since they indicate the force of destruction of the surface layer of a structure.

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Basaldella, Marco, Marvin Jentsch, Nadja Oneschkow, Martin Markert, and Ludger Lohaus. "Compressive Fatigue Investigation on High-Strength and Ultra-High-Strength Concrete within the SPP 2020." Materials 15, no. 11 (May 26, 2022): 3793. http://dx.doi.org/10.3390/ma15113793.

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The influence of the compressive strength of concrete on fatigue resistance has not been investigated thoroughly and contradictory results can be found in the literature. To date, the focus of concrete fatigue research has been on the determination of the numbers of cycles to failure. Concerning the fatigue behaviour of high-strength concrete (HPC) and, especially, ultra-high-strength concrete (UHPC), which is described by damage indicators such as strain and stiffness development, little knowledge is available, as well as with respect to the underlying damage mechanisms. This lack of knowledge has led to uncertainties concerning the treatment of high-strength and ultra-high-strength concretes in the fatigue design rules. This paper aims to decrease the lack of knowledge concerning the fatigue behaviour of concrete compositions characterised by a very high strength. Within the priority programme SPP 2020, one HPC and one UHPC subjected to monotonically increasing and cyclic loading were investigated comparatively in terms of their numbers of cycles to failure, as well as the damage indicators strain and stiffness. The results show that the UHPC reaches a higher stiffness and a higher ultimate strain and strength than the HPC. The fatigue investigations reveal that the UHPC can resist a higher number of cycles to failure than the HPC and the damage indicators show an improved fatigue behaviour of the UHPC compared to the HPC.

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Kojima, M. "Ultra-high-strength Concrete." Concrete Journal 54, no. 5 (2016): 554–58. http://dx.doi.org/10.3151/coj.54.5_554.

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Ghafoori, Nader, Matthew O. Maler, Meysam Najimi, and Ariful Hasnat. "Abrasion resistance of high early-strength concrete for rapid repair." MATEC Web of Conferences 289 (2019): 02002. http://dx.doi.org/10.1051/matecconf/201928902002.

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This paper examines the abrasion resistance of high early-strength concrete developed for rapid repair of highways and bridge decks. The cement types chosen for this study included ASTM Type III, ASTM Type V, and Calcium Sulfoaluminate (CSA) cements. A cement content of 386 kg/m3 (650 lb/yd3) was maintained for all studied concretes. Test samples were tested after 24 hours and 28 days of curing in order to evaluate compressive strength and depth of wear. Test results revealed that the opening time to attain minimum required compressive strength for CSA cement concrete was one hour, whereas the values for Type V and Type III cement concretes were 8.5 and 6 hours, respectively. After 24 hours curing, CSA cement concrete displayed the highest strength, but lowest resistance to wear. The 28-day cured CSA cement concrete produced the highest strength and resistance to abrasion, while Type III cement concrete showed a similar strength, but lower resistance to wear, when compared to those of the Type V cement concrete.

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Kadri, E. H., S. Aggoun, S. Kenai, and A. Kaci. "The Compressive Strength of High-Performance Concrete and Ultrahigh-Performance." Advances in Materials Science and Engineering 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/361857.

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The compressive strength of silica fume concretes was investigated at low water-cementitious materials ratios with a naphthalene sulphonate superplasticizer. The results show that partial cement replacement up to 20% produce, higher compressive strengths than control concretes, nevertheless the strength gain is less than 15%. In this paper we propose a model to evaluate the compressive strength of silica fume concrete at any time. The model is related to the water-cementitious materials and silica-cement ratios. Taking into account the author's and other researchers’ experimental data, the accuracy of the proposed model is better than 5%.

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Sh. Rasheed, Laith, Alaa M.Hadi, Ruaa Hussain Elewi, and Marwa R.Aziz. "Some Mechanical Properties of Retempered High Strength Concrete." University of Thi-Qar Journal for Engineering Sciences 4, no. 2 (August 1, 2013): 96–111. http://dx.doi.org/10.31663/utjes.v4i2.206.

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Iraq climate is characterized by the temperature increase during most of the months. The ambient temperatures are considered the most important factor that effects the production, properties and durability of the concrete. This study aims to evaluate the effect of retempering concrete after 60 minutes from cast by three different methods (retempring by water, retempring by Superplasticizer(G51) and retempring by remixing)on some of the mechanical properties of High Strength Concrete (HSC).In this work, different tests methods are adopted such as compressive strength, splitting tensile strength, ultrasonic pulse velocity and a hammer rebound Schmidt tests. These tests are investigated at different ages (7, 14, 28, and 56 days). The results show the high strength concrete that retempered by superplasticizer ) G51 leads to higher strengths, higher Ultrasonic Pulse Velocity (UPV) and higher hammer rebound than direct cast. The rate of increase in the mechanical properties of the high strength concrete that retempered by G51 relative to direct cast concrete at age 56 days were 28.29% ,16.37%, 2.76%,and 16.02% for compressive strength, splitting strength, Ultrasonic Pulse Velocity (U.P.V.) and hammer rebound respectively.While the concrete that retempered by water leads to lower strengths , lower Ultra Sonic Pulse Velocity (UPV) and lower hammer rebound than the other mixes.For the High Strength Concrete (HSC) mixes, the compressive strength and splitting tensile strength are closely related to UPV with a high correlation coefficient, R2.

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Kaprielov, S. S., A. V. Sheynfeld, Al-Omais Dzhalal, A. S. Zaitsev, and R. A. Amirov. "A technology of erecting high-rise building frame structures using B60-B100 classes high-strength concretes." Bulletin of Science and Research Center of Construction 33, no. 2 (July 10, 2022): 106–21. http://dx.doi.org/10.37538/2224-9494-2022-2(33)-106-121.

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Introduction. The article presents a technology of erecting of high-rise building's frame structures made of B60-B100 classes high-strength concretes. This technology includes a complex of processes and considers a number of special features, the most significant of which are connected with the specific character of high-strength concretes and concreting climatic conditions.Aim. To determine the main requirements for the technology of concreting and parameters of curing the monolithic structures of high-rise buildings made of B60-B100 classes high-strength concretes, including at winter periods, at the various stages of their erection.Methods and materials. Studies were carried out on the effect of hardening temperature variations from +5 to +50 °С on the hardening kinetics of B60, B80, and B100 classes concretes. Based on the 15-year experience of the “Moscow-City” construction, the mix proportions of high-strength concretes were optimized, as well as the main technological parameters of concreting and curing the frame structures located at an altitude of up to 370 m were analyzed and summarized.Results. The mix proportions of B60-B100 classes concretes of high-workability and self-compacting mixtures with a cement consumption of 350–480 kg/m3 was optimized using standard materials and MB-type organomineral modifiers. The performed study revealed a regularity between the strength and the temperature-temporal parameter of concrete curing, which is applicable for a preliminary assessment of strength characteristics in high-strength concrete structures on the basis of their temperature measurement results. A systematic approach to concrete curing and the maintenance of building structures as a whole with the vertical division of a high-rise building into four temperature zones led to a reducing the probability of thermal cracks appearance.Conclusions. According to the results of the study, the proposed complex of technological solutions concerning compositions and properties of concrete mixtures and concretes, the technology of concreting, as well as the methods of heating and curing the concrete of structures at the various stages of their erection ensures thermal resistance to cracks at the early stage of concrete hardening, as well as the high quality and assigned rates of construction.

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Luosun, Yi Ming, Jun Zhang, and Yuan Gao. "Evaluation of Shrinkage Resulted Cracking of High Strength Calcium Sulfoaluminate Cement Concrete with Impact of Internal Curing." Key Engineering Materials 629-630 (October 2014): 144–49. http://dx.doi.org/10.4028/www.scientific.net/kem.629-630.144.

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In this paper, restrained ring test and shrinkage test are carried on three kinds of concrete—high-strength portland cement concrete, high-strength calcium sulfoaluminate cement concrete and high-strength calcium sulfoaluminate cement concrete with internal curing in order to evaluate the shrinkage induced cracking performance of the concretes. The experimental results show that calcium sulfoaluminate cement concrete exhibits lower shrinkage caused by surface drying comparing to portland cement concrete. Internal curing can eliminate most of the autogenous shrinkage of concrete. In the ring test, the latter two concrete did not crack during the whole test history—42 days, while high-strength portland cement concrete cracked at the 13th day after casting. High strength calcium sulfoaluminate cement concrete exhibits better anti-cracking ability than the high strength portland cement concrete with the same strength grade.

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Bashandy, Alaa Ali, Noha M. Soliman, and Mahmoud Hamdy Abd Elrahman. "Recycled Aggregate Self-curing High-strength Concrete." Civil Engineering Journal 3, no. 6 (July 3, 2017): 427–41. http://dx.doi.org/10.28991/cej-2017-00000102.

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The use of recycled aggregates from demolished constructions as coarse aggregates for concrete becomes a need to reduce the negative effects on the environment. Internal curing is a technique that can be used to provide additional moisture in concrete for more effective hydration of cement to reduce the water evaporation from concrete, increase the water retention capacity of concrete compared to the conventionally cured concrete. High strength concrete as a special concrete type has a high strength with extra properties compared to conventional concrete. In this research, the combination of previous three concrete types to obtain self-curing high-strength concrete cast using coarse recycled aggregates is studied. The effect of varying water reducer admixture and curing agent dosages on both the fresh and hardened concrete properties is studied. The fresh properties are discussed in terms of slump values. The hardened concrete properties are discussed in terms of compressive, splitting tensile, flexure and bond strengths. The obtained results show that, the using of water reducer admixture enhances the main fresh and hardened properties of self-curing high-strength concrete cast using recycled aggregate. Also, using the suggested chemical curing agent increased the strength compared to conventional concrete without curing.

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R, Sriram, Mr Prabakaran, and Mrs Uma Nambi. "Experimental Study on High Strength Concrete using Industrial Wastes." International Journal of Trend in Scientific Research and Development Volume-3, Issue-3 (April 30, 2019): 976–80. http://dx.doi.org/10.31142/ijtsrd23155.

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Ashutosh Vijay, Dalavi, and Chetan S Patil. "Performance Evaluation of High Strength Basalt Fibre Reinforced Concrete." International Journal of Scientific Engineering and Research 10, no. 12 (December 27, 2022): 5–10. https://doi.org/10.70729/se221213080605.

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Vamsi Krishna S, B. "Ceraplast and Ceraproof Admixtures Behaviour on High Strength Concrete." International Journal of Scientific Engineering and Research 2, no. 5 (May 27, 2014): 15–19. https://doi.org/10.70729/j2013277.

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K.L., Ravisankar. "Experimental Investigation on High Strength Concrete Using Polypropylene Fiber." Journal of Advanced Research in Dynamical and Control Systems 11, no. 12 (December 31, 2019): 193–200. http://dx.doi.org/10.5373/jardcs/v11i12/20193372.

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Saeed, Srakawt Abdul-Rahman. "Experimental Study of High Strength Fibrous Reinforced Concrete Slabs." Journal of Zankoy Sulaimani - Part A 9, no. 1 (June 17, 2004): 7–16. http://dx.doi.org/10.17656/jzs.10144.

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Sanytsky, Myroslav, Тetiana, Kropyvnytska, Orest Shyiko, Yurii Bobetskyi, and Andriy Volianiuk. "High strength steel fiber reinforced concrete for fortification protected structures." Theory and Building Practice 2023, no. 1 (June 20, 2023): 37–42. http://dx.doi.org/10.23939/jtbp2023.01.037.

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The article presents the results of research on modified steel fiber-reinforced concrete and shows the expediency of their use to increase the effectiveness of fortification protection structures against shock loads. It was established that according to the results of tests of compressive strength (fсm = 79.4 MPa) and tensile strength during bending (fс, lf = 7.4 MPa), steel fiber-reinforced concrete can be classified as high-strength (strength class C 50/60) and rapid-hardening (fcm2/ fcm28 = 0.57) in accordance with DSTU EN 206:2018. Manufacturing in factory conditions of reinforced concrete elements of structures based on high-strength steel fiber-reinforced concrete with increased resistance to various types of force effects during shelling will allow to obtain quick-assembling/quick-dismantling fortification structures that will be able to provide protection for the personnel of the units of the armed forces of Ukraine.

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Parniani, Sasan, Mohd Warid Hussin, and Farnoud Rahimi Mansour. "Compressive Strength of High Volume Slag Cement Concrete in High Temperature Curing." Advanced Materials Research 287-290 (July 2011): 793–96. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.793.

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Recent consideration has been given to use of GGBFS as separate cementitious material mixed along with Portland cement in production of concrete. Problems are frequently encountered in producing good-quality concrete specially slag cement concrete in hot climates.Curing problems are exaggerated when concreting in hot weather, as a result of both higher concrete temperatures and increased rate of evaporation from the fresh mix. The disadvantage of GGBFS concretes is that they proved to be more sensitive to poor curing than OPC Therefore, special care must be taken when using this type of concrete, especially on site, where the working conditions and the application of curing are not as easy to control as in the laboratory concrete. The purpose of this paper is investigation and evaluation strength loss in slag cement concrete in poor curing situation. To carry out this aim, 72 cube specimens with three different proportion of slag are made and cured in two different conditions. And result of compressive tests compared together to determine susceptibility of GGBFS concrete in hot-dry condition.

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Křížová, Klára, Martin Ťažký, Milan Meruňka, and Ondřej Pikna. "Study of High Strength Concretes with Variability of Composition Designs." Solid State Phenomena 325 (October 11, 2021): 156–61. http://dx.doi.org/10.4028/www.scientific.net/ssp.325.156.

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High Strength Concretes (HSC) are concretes defined mainly by compressive strength. The strength of concrete can guarantee other excellent results of properties, namely durability. Essential for the production of HSC is a careful approach to the design of concrete composition, especially the quality of raw materials. It is primarily necessary to increase the content of the binder combined mainly with Portland cement and another admixture. Due to its excellent properties, Silica fume is largely used as an admixture, where it is necessary to consider its effective amount. It is also suitable to combine this admixture with other types of active admixtures. The question of the type of coarse aggregate fractions used is crucial. The quality and purity of aggregates is an essential part of the quality design of these concretes, influencing practically all the resulting parameters of concrete. The article presents a set of tests on designed High strength Concretes, differing in the composition of the concrete to demonstrate the variability of the design concept and its effect on the resulting values of strength and durability.

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Dong, Chun Min, Ke Dong Guo, and Jia Jia Sun. "A New Calculation Method for Cracking Width of Beam with High Strength Rebar." Advanced Materials Research 243-249 (May 2011): 415–18. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.415.

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With the application of high strength concrete and rebar, the influence of concrete strength on cracking width of reinforced concrete beam with high strength rebar is becoming more and more important. To investigate the effect of concrete strength on cracking width of reinforced concrete beam with high strength rebar, the experiment including 6 simply supported T-beams with high-strength rebar and 2 beams with ordinary-strength rebar have been made. Then the relevant specifications advised in Code for Design of Concreter Structure (GB50010-2002) are revised according to the experiment results so as to considering the influence of concrete on cracking width. A new cracking width method considering the influence of concrete strength on cracking width for reinforced concrete beam with high strength rebar is proposed. Finally, the comparisons between predictions and experiment results have been conducted, which shown that the proposed new cracking width method agreed with experiment results well.

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Journal articles on the topic 'High strength concrete'

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