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Showing 1 to 18 of 18 for “"superplasticizer"”.
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Effects of maximum size coarse aggregate and superplasticizer on concrete strength
The effects of maximum size coarse aggregate on the relationship between accelerated strength and 14-day normally cured strength of normal and superplasticized concrete have been investigated. The results obtained show that differences among maximum size coarse aggregates are greater in normal …
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Interactions Between Portland Cements and Carboxylated and Naphthalene-Based Superplasticizers
… However, concretes required much less superplasticizer than paste to be dispersed. The differences in the shear history between the concretes and the pastes possibly explain such discrepancies in admixture dosages.
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Co-Extrusion of Cement -Based Materials to Achieve Functionally Graded Microstructure
… of silica fume, polyethylene glycol and superplasticizer was found to be efficient to reduce air voids in extrudates.
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Kinetics of microfine cement filtration during constant rate permeation through sands
… of 2:1 and 3:1 with 2 percent by weight of superplasticizer. During the permeation, the pressure buildup at the bottom of the sand columns was measured and the effluent was collected to determine the cement concentration of the grout with time for the duration of the permeation. After …
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INVESTIGATION ON RHEOLOGY OF CEMENT PASTE AND CONCRETE AT HIGH TEMPERATURE
… rheology of portland cement paste incorporating superplasticizers were also investigated. Results suggested that polycarboxylate-based superplasticizers should be used at a dosage close to the saturation in order to ensure adequate rheological behaviour at high temperature and prolonged mixing …
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INVESTIGATION ON RHEOLOGY OF CEMENT PASTE AND CONCRETE AT HIGH TEMPERATURE
… rheology of portland cement paste incorporating superplasticizers were also investigated. Results suggested that polycarboxylate-based superplasticizers should be used at a dosage close to the saturation in order to ensure adequate rheological behaviour at high temperature and prolonged mixing …
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Effect of Admixtures, Chlorides, and Moisture on Dielectric Properties of Portland Cement Concrete in the Low Microwave Frequency Range
… curing period, admixture type (microsilica, superplasticizer, and shrinkage admixture), and chloride content on the dielectric properties of PCC. Measurements were conducted in the time domain and converted to the frequency domain using Fast Fourier Transform. The research found that an …
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STRATEGIES TO IMPROVE SHRINKAGE RESISTANCE OF CEMENT-BASED MATERIALS FOR EXTRUSION-BASED 3D PRINTING
… the influence of water-to-cement ratio, superplasticizer dosage, and welan gum content on mortar printability; iii) propose a “printability window” where rheological properties and desorptivity can secure successful printing; iv) investigate effect of shrinkage mitigation materials …
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Concrete Rheology
… type, fly ash content and the addition of a superplasticizer on the rheological parameters of yield stress, plastic viscosity, and apparent viscosity. The objective of this work was not only to measure the effects on rheology by the variables, but also to predict some of the same measured …
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Avaliação das incertezas nas informações sobre as resistências à tração na flexão e compressão de argamassas cimentícias com lodo de ETA
… 40 %), whereas the mixture with 5 % WTS and superplasticizer maintained a consistency similar to that of the standard mortar. Regarding mechanical performance, the addition of 10 % dried WTS reduced flexural strength by approximately 64 % (2.7 MPa → 7.4 MPa control) and compressive strength …
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The potential of porcelain waste as sand replacement to produce high strength concrete
… water cement ratio adopted is 0.5 and 0.37 when superplasticizer was added with mix proportion of concrete 1:1.5:3. The sand was replaced with porcelain waste at 10 %, 20 %, 30 %, 40 % and 50 %. Laboratory investigation were focused on examining the mechanical properties and thermal properties of …
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APPLICATION OF TAGUCHI'S ORTHOGONAL ARRAY IN AN EXPERIMENT FOR FORMULATION OF CEMENTITIOUS REPAIR MATERIAL
… sulphate, calcium carbonate, silica sand, resin, superplasticizer, low cellulose, defoamer, retarder and accelerator. This self-leveling mortar is characterized by the following properties: compressive strength, flow value, tensile bond adhesion, abrasion resistance, and length change. In this …
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Ultrasonic wave reflection measurements on self-compacting pastes and concretes
… times of pastes varied linearly with w/c, that superplasticizer and fly ash delayed the set times of pastes, and that differences in w/cm, sp/cm, and fa/cm could be detected. Final set times determined from UWR correlated well with those from penetration resistance. Initial set times from S-wave …
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Rheology of grout for preplaced aggregate concrete. Investigation on the effect of different materials on the rheology of Portland cement based grouts and their role in the production of preplaced aggregate concrete.
… or mineral additives had first employed, then superplasticizer (SP) was added at 2% and 1%, and finally a combination of 1% SP and pulverized fuel ash (Pfa) at 20% of the cement weight was employed for all mixes. Grout tests have included two point workability tests by the Viskomat NT, flow …
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Experimental Compressive Behavior and Numerical Modeling of Unconfined and Confined Ultra-High Performance Concrete
… sand, ground quartz, high-range water reducer (superplasticizer), less than 0.25 water-to-cement ratio, and fibers (mostly steel fibers).Fibers play a crucial role in enhancement of the strength and ductility of UHPC in both tension and compression. Addition of fibers make the material to fail …
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Engineering properties and structural behaviour of high strength reinforced concrete beams
… factors such as w/c ratios, silica fume and superplasticizer dosages on compressive strength and splitting tensile strengths in the range of 80 to 120 N/mm<sup>2</sup> (MPa) were studied. Additionally, new mathematical expressions were developed to replace some of the currently used …
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Evaluating CEN/TS 12390-9 To Assess Concrete for UK Freeze-Thaw Exposure Conditions
… than 250 µm apart. Development of 3rd generation superplasticizers combined with air entrainers, both air and non-air entrained concretes had a spacing factor value less than 250 µm (and for most concretes <100 µm), however many of the non-air entrained concretes did not achieve an Acceptable …
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Dispersion of graphene nanoplatelets in water with surfactant and reinforcement of mortar with graphene nanoplatelets
This research investigated the dispersion behavior of graphene nanoplatelets (GNPs) in water with water reducing admixture (WRA), a type of surfactant. The dosage of GNPs was fixed at 0.2wt% of water, and the dosage of the WRA functioned as the controlled variable. Sedimentation experiments …