scholarly journals Basic Experimental Evaluation of Fresh and Hardened Properties of Mortar Using Additive Manufacturing

2021 ◽  
Vol 21 (6) ◽  
pp. 167-176
Author(s):  
Seong-Jin Woo ◽  
In-Beom Park ◽  
Dong-Min Lee ◽  
Jun-Mo Yang
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Additive Manufacturing ◽  
Surface Defects ◽  
Constant Width ◽  
Rate Of Change ◽  
Time Interval ◽  
Construction Time ◽  
Lateral Direction ◽  
Flexural Tensile Strength

Recently, the three-dimensional concrete printing (3DCP) method has been garnering considerable interest owing to its ability to significantly reduce the construction time. In this study, 3D printing or additive manufacturing was applied to mortar using a small gantry type equipment and the performance of the method was evaluated. The mixture proportioning for good mortar printing and deposition was derived. The parameters of printability, buildability, compressive strength, flexural tensile strength, and anti-washout were considered for the performance evaluation. The results showed good printability with a constant width and no surface defects. In the buildability test, the rate of yield stress development increased, and the rate of change in the layer height decreased as the interlayer time interval increased during underwater printing. The flexural tensile strength of the specimen cast into the mold was lower than that of the specimen extracted from the additive parts owing to the longitudinal confinement during printing. The compressive strength in the lateral direction was slightly higher than that in the perpendicular direction, whereas the compressive strength of the specimen extracted from the part printed underwater was higher than that of the specimen cast into the mold.

Experiment and Research on Mechanic Behavior of Concrete with Different Addition Amounts of Polypropylene Fibers

2012 ◽  
Vol 430-432 ◽  
pp. 1064-1067
Author(s):  
Yu Zhi Chen ◽  
Wei Hong Xuan ◽  
Xiao Hong Chen
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Polypropylene Fiber ◽  
Polypropylene Fibers ◽  
Flexural Tensile Strength ◽  
Axial Compressive Strength ◽  
Low Dosage

The effect of the different addition amounts of polypropylene fibers on the basic mechanical properties of concrete were investigated in this paper. The results show that the flexural tensile strength of concrete changed slightly after adding low-dosage polypropylene fiber(0.04%～0.16%); Axial compressive strength and flexural tension modulus decreased, limiting flexural strain increased gradually with the amounts of fibers rising.

scholarly journals Silicate conductive composites with graphite-based fillers

2021 ◽  
Vol 1209 (1) ◽  
pp. 012035
Author(s):  
Š Baránek ◽  
V Černý ◽  
G Yakovlev ◽  
R Drochytka
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Construction Industry ◽  
Machine Building ◽  
Building Industry ◽  
Electrically Conductive ◽  
Conductive Composites ◽  
Flexural Tensile Strength ◽  
Overvoltage Protection

Abstract Electroconductive composites are modern materials that are commonly used in many industries such as construction industry and machine-building industry. For example, these materials can be useful as sensors for monitoring changes in constructions, shielding stray currents from electrification networks, shielding electromagnetic radiation in operating rooms, cathodic protection against moisture or overvoltage protection of buildings. The topic of this post is the research of electrically conductive silicate composites with graphite-based fillers. In this research will be tested composites with different ratio and types of graphite and monitor their electroconductive properties like impedance, and physical-mechanical properties like compressive and tensile strength. The post describes basic properties and interactions of silicate electrically conductive composites with graphite fillers. It was found that by adding 10 % wt. graphite into silicate composites, impedance is reduced by 50% and compressive strength by 40%. The flexural tensile strength depends mainly on the roughness of the particles, where the coarser flaky particles transfer the load better and increase the strength while very fine graphites reduce the flexural tensile strength. Furthermore, it has been found that very finely ground synthetic graphites are most suitable for achieving low impedance of composites.

scholarly journals Determination of Mechanical Properties of Slurry Infiltrated Steel Fiber Concrete Using Fly Ash and Metakaolin

2018 ◽  
Vol 7 (4.5) ◽  
pp. 262
Author(s):  
Shelorkar A.P ◽  
Jadhao P.D
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Fly Ash ◽  
Impact Energy ◽  
Steel Fiber ◽  
Volume Fraction ◽  
Strength Properties ◽  
Steel Fibers ◽  
Flexural Tensile Strength ◽  
Fiber Concrete

This paper reports on a wide-ranging study on the properties of slurry infiltrated fiber concrete containing fly ash, Metakaolin, and hook ended steel fibers. Properties studied include workability of fresh slurry infiltrated fiber concrete, and compressive strength, flexural tensile strength, splitting tensile strength, dynamic elasticity modulus, impact energy of hardened slurry infiltrated fiber concrete. Fly ash and Metakaolin content used was 0%, 2.5%, 5.0%, 7.5% and 10% in mass basis, and hook ended steel fibers volume fraction was 0%, 2.0%, 3.0% and 4.0% in volume basis. The laboratory results showed that steel fiber addition, either into control concrete or fly ash, Metakaolin blend slurry infiltrated fiber concrete; improve the tensile strength properties, flexural strength, impact energy and modulus of elasticity. In this experimental study, compressive strength improvement ratio is 33.60%, and Structural efficiency is 9.50 % higher in slurry infiltrated fiber-concrete with Metakaolin as compared with fly ash based slurry infiltrated fiber concrete at the 4% replacement ratio of hook ended steel fibers by volume.  

Influence of Soil Grading on the Mechanical Behavior of Earth Cement Blocks

MRS Advances ◽  
2020 ◽  
Vol 5 (54-55) ◽  
pp. 2771-2782
Author(s):  
Sathiyapireyanga Jeyasegaram ◽  
Navaratnarajah Sathiparan
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Experimental Program ◽  
Soil Composition ◽  
Fine Content ◽  
Uniformity Coefficient ◽  
Flexural Tensile Strength ◽  
Soil Cement ◽  
Cement Soil

AbstractThe characteristics of earth cement blocks depend on soil composition, grading of the soil, cement-soil ratio and water content, etc… In the present study, an experimental program is conducted to evaluate the influence of soil grading in the mechanical properties of earth cement blocks. Five gradings of soil used for the preparation of earth cement blocks. Soil grading effect on following properties of earth-cement blocks such as block density, compressive strength in wet and dry condition, flexural tensile strength in wet and dry condition, and water absorption was compared. Results show that the properties of the earth cement blocks are dependent upon the fine content and uniformity coefficient of the soil. The increase in the finer content in mortar improves water absorption, compressive strength and flexural tensile strength.

scholarly journals Assessment the thermal properties lightweight concreteproduced by using local industrial waste materials

2018 ◽  
Vol 162 ◽  
pp. 02027
Author(s):  
Osama AbdulAmeer
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Industrial Wastes ◽  
Fine Aggregate ◽  
Light Weight ◽  
Wood Sawdust ◽  
Flexural Tensile Strength ◽  
Light Weight Concrete

In this research study of the thermal properties of light weight concrete produced from using two locally industrial wastes materials, to evaluate the thermal insulation, and some physical properties like strength of concrete (compressive and flexural tensile strength and variation of density of light weight concrete. Two types of wastes admixtures were used in this study, (chopped rubber, and wood sawdust) with (5%, 10%, 15% and 20%) percent of each one. Thermal conductivity, compressive strength, flexural tensile strength and variation of density have been examined for each specimen at all percentages of admixtures, and compare with the reference concrete specimens. Experimental test results indicated that using these types of wastes as replacement of fine aggregate in concrete significantly affects the thermal conductivity, compressive strength, flexural tensile strength (rise or fall out), especially at (5%) of adding materials, as well as utilization of additives in concrete to produce low density mixture with wood sawdust or as high density concrete when using rubber chopped in the concrete mixture.

scholarly journals Mechanical and Fracture Parameters of Ultra-High Performance Fiber Reinforcement Concrete Cured via Steam and Water: Optimization of Binder Content

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2016
Author(s):  
Avan Ahmed Mala ◽  
Aryan Far H. Sherwani ◽  
Khaleel H. Younis ◽  
Rabar H. Faraj ◽  
Amir Mosavi
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
High Performance ◽  
Mechanical Performance ◽  
Binder Content ◽  
Splitting Tensile Strength ◽  
Steam Curing ◽  
Flexural Tensile Strength ◽  
High Performance Fiber ◽  
Curing Methods

An investigational study is conducted to examine the effects of different amounts of binders and curing methods on the mechanical behavior and ductility of Ultra-High Performance Fiber Reinforced Concretes (UHPFRCs) that contain 2% of Micro Steel Fiber (MSF). The aim is to find an optimum binder content for the UHPFRC mixes. The same water-to-binder ratio (w/b) of 0.12 was used for both water curing (WC) and steam curing (SC). Based on the curing methods, two series of eight mixes of UHPFRCs containing different binder contents ranging from 850 to 1200 kg/m3 with an increment of 50 kg/m3 were produced. Mechanical properties such as compressive strength, splitting tensile strength, static elastic module, flexural tensile strength and the ductility behavior were investigated. This study revealed that the mixture of 1150 kg/m3 binder content exhibited the highest values of the experimental results such as a compressive strength greater than 190 MPa, a splitting tensile strength greater than 12.5 MPa, and a modulus of elasticity higher than 45 GPa. The results also show that all of the improvements began to slightly decrease at 1200 kg/m3 of the binder content. On the other hand, it was concluded that SC resulted in higher mechanical performance and ductility behavior than WC.

scholarly journals MULTI-CRITERIA OPTIMIZATION OF THE FIBER CONCRETES COMPOSITIONS OF RIGID PAVEMENT

2021 ◽  
Vol 3 (1) ◽  
pp. 62-71
Author(s):  
S. Kroviakov ◽  
◽  
A. Mishutin ◽  
L. Chintea ◽  
◽  
...  
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Statistical Models ◽  
Frost Resistance ◽  
Polypropylene Fiber ◽  
Optimization Method ◽  
Operating Conditions ◽  
Rigid Pavement ◽  
Flexural Tensile Strength ◽  
Fiber Concrete

The experiment was carried out according to the optimal plan, which four factors of the composition of modified fiber concrete for rigid pavement were varied: amount of Portland cement, polypropylene fiber, metakaolin and polycarboxylate type additive. All concrete mixtures had equal mobility P2. Complex of experimental-statistical models describe the influence of factors on the properties of concrete is obtained. Selection of optimal compositions of fiber concrete of a rigid pavement was carried out using the obtained experimental-statistical models. Graphical optimization method for "squares and squares" diagrams was used. The square in the coordinates "amount of metakaolin" - "amount of complex action additive Coral ExpertSuid-5" was used as a carrier in the construction of diagrams. These values of the mechanical characteristics of concrete were used as limitation criteria: compressive strength at the age of 3 and 28 days, flexural tensile strength, frost-resistance, abrasion. Frost-resistance and abrasion are the main indicators that ensure the durability of concrete for rigid pavement in typical operating conditions. The concrete prime cost indicator was used as an optimization criterion. 2 variants of concretes compositions of classes C30/35 and C32/40 with increased durability and high strength was chosen. The selected compositions of C30/35 class concretes have frost-resistance F350, flexural tensile strength 8.0-8.2 MPa, abrasion 0.38-0.39 g/cm2, compressive strength at 3 days age 35 MPa and strength at 28 days age 54 MPa. The selected compositions of C32/40 class concretes have frost-resistance F400, flexural tensile strength 8.5-8.6 MPa, abrasion 0.34 g/cm2, compressive strength at 3 days age 38-39 MPa and strength at 28 days age 57-58 MPa. All four selected compositions have the amount of metakaolin 15-20 kg/m3, polypropylene fiber 0.9-1.5 kg/m3, polycarboxylate type additive Coral ExpertSuid-5 0.8-0.9% of the cement mass.

scholarly journals Influence of Addition Contents of Iron Ore Tailings on Structural Mortar

2021 ◽  
Vol 11 (1) ◽  
pp. 74
Author(s):  
Nara Linhares Borges de Castro ◽  
Bruna Silva Almada ◽  
Abner Araújo Fajardo ◽  
Carlos Augusto Oliveira ◽  
White José dos Santos
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Physical Properties ◽  
Open Porosity ◽  
Iron Ore ◽  
Cementitious Composites ◽  
Carbonation Depth ◽  
Flexural Tensile Strength ◽  
Iron Ore Tailings

This study discusses and analyzes an alternative of IOT reuse as addition in structural mortars, evaluating the influence of IOT addition contents. The material was physically and chemically characterized. Structural mortars were molded with 10%, 20%, 30% and 40% of addition of IOT in relation to cement mass. We investigate physical properties, mechanical indicators, durability indicators and microstructure. The tailings are composed of predominantly quartz, hematite and goethite, and no components were found that could compromise the cementitious composites. The addition of IOT provided a tendency to reduce open porosity. The addition of 30% IOT was the most efficient in closing pores. All addition contents led to the maintenance or gains in mechanical properties, and a 10% gain in flexural tensile strength was observed for the addition of 10% IOT. The addition of 40% IOT promoted a 14% gain in compressive strength and maintenance of flexural tensile strength. This addition content evidences that the carbonation depth was not significantly affected. Based on the results, the addition percentages of 30-40% are interesting as to the analyzed properties.

Evaluating the co-relationship between concrete flexural tensile strength and compressive strength

2014 ◽  
Vol 5 (2) ◽  
pp. 115 ◽  
Author(s):  
Mohd. Ahmed ◽  
Khalid Mohammad El Hadi ◽  
Mohammad Abul Hasan ◽  
Javed Mallick ◽  
Akil Ahmed
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Tensile Strength

Mechanical Strength of Hydraulic Binder Made by Blending Type I Portland Cement and Pozzolan

2015 ◽  
Vol 776 ◽  
pp. 36-40
Author(s):  
I Made Alit Karyawan Salain
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Portland Cement ◽  
Mechanical Strength ◽  
Type I ◽  
Natural Pozzolan ◽  
Flexural Tensile Strength ◽  
Mix Proportion ◽  
Hydraulic Binder ◽  
Chemical Content

The mechanical strength of hydraulic binder made by blending type I Portland cement (PC) and pozzolan has been examined at the age of 3, 7, 14, 28 and 90 days.The mechanical strength test was realized by using mortar specimens measuring 40x40x160 mm according to NF EN 196-1. The mix proportion of mortarwas 0.5 water :1.0 hydraulic binder : 3.0 sand, by weight.The hydraulic binder was a mixture of 80% PC and 20% pozzolan. Five types of pozzolan were used in this study: two natural pozzolan and three artificial pozzolan. As a control, it was made a mortar havingthe same proportion except that the hydraulic binder was 100% PC. The test result showsthat all of pozzolan present a good pozzolanic reactivity. At 3 days,the strength of the mortar with blended binder (MBB) is lower than the strength of the control mortar (CTM). At that time, the flexural tensile strength and the compressive strength of the MBB rangerespectively from 5.23 to 6.81 MPa and from 13.61 to 18.37 MPa, whereas the CTM strength has reached 7.30 MPa and 27.92 MPa. The MBB strength increasesand it canachieve or even exceed the CTM strengthwith increasing age of hydration. In fact, at 90 days, the flexural tensile strength and the compressive strength ofMBB can reach about 10.08 to 11.06 MPa and 49.69 to 54.17 MPa respectively. In this period of hydration, the flexural tensile strength and the compressive strength of CTM are only 10.13 MPa and 49.00 MPa. The different development of the mechanical strength of MBB could be stronglyrelated to the chemical content of the pozzolan used, especially, reactive silica and reactive alumina.

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