scholarly journals Supersulfated Cement Applied to Produce Lightweight Concrete

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 403
Author(s):  
Liliya Kazanskaya ◽  
Olga Smirnova ◽  
Ángel Palomo ◽  
Ignacio Menendez Pidal ◽  
Manuel Romana

The physical and mechanical characteristics of expanded-clay lightweight concrete based on a supersulfated binder in comparison with lightweight concrete based on ordinary Portland cement were studied. In replacing CEM 32.5 with a supersulfated binder of 6000 cm2/g specific surface, one can increase the tensile strength in bending up to 20% and can increase the ratio of the tensile strength in bending to the compressive strength that indicates the crack resistance increase of concrete. Compressive strengths at the age of 28 days were equal to 17.0 MPa and 16.6 MPa for the supersulfated binder of 3500 cm2/g specific surface and CEM 32.5, respectively. Shrinkage deformation of hardening concrete, indicators of fracture toughness, frost resistance, and thermal conductivity were determined during the experimental works. The coefficient of thermal conductivity decreased up to 12% compared to the use of CEM 32.5. An enhancement in concrete properties was associated with the increase of supersulfated binder fineness.

2018 ◽  
Vol 245 ◽  
pp. 03019 ◽  
Author(s):  
Artemiy Cherkashin ◽  
Yasmin Begich ◽  
Polina Sherstobitova ◽  
Oleg Tolochko

The article deals with the use of amorphous fiber of the Fe-B-C system, which was obtained by spinning the melt. Comparative tests of the samples made on the basis of the test material on the compressive strength and tensile strength of the traditional destructive method were made. The conductivity of the samples was also tested. Physical and mechanical characteristics of the material are obtained.


2017 ◽  
Vol 10 (1) ◽  
pp. 122-140
Author(s):  
A. L. SARTORI ◽  
L. M. PINHEIRO ◽  
R. M. DA SILVA ◽  
S. B. FREITAS ◽  
T. G. CESAR

Abstract This paper describes the adherence behavior of a structural lightweight concrete with EPS beads (SLCEB) in a monotonic loading, based in a bibliographic review and in pull-out tests. The results of these SLCEB tests were compared with those of an ordinary concrete (OC) and with the values based in indications of the Brazilian code ABNT NBR 6118:2014 - Design of concrete structures. The pull-out tests of two batches of SLCEB and one of OC were analyzed, in a total of 60 tests. Mechanical characteristics were determined too, such as: compressive strength and tensile strength in split cylinder test. The calculated results according to the above mentioned standard were very different from those obtained in the tests, indicating that the theoretical values are more conservative than the experimental ones. It was also verified that it is possible to use SLCEB in structures with respect to the adequate adherence of reinforcement in the concrete.


Author(s):  
Mazhar Hussain ◽  
Daniel Levacher ◽  
Nathalie Leblanc ◽  
Hafida Zmamou ◽  
Irini Djeran Maigre ◽  
...  

Crude bricks are composite materials manufactured with sediments and natural fibers. Natural fibers are waste materials and used in construction materials for reinforcement. Their reuse in manufacturing reinforced crude bricks is eco-friendly and improves mechanical and thermal characteristics of crude bricks. Factors such as type of fibers, percentage of fibers, length of fibers and distribution of fibers inside the bricks have significant effect on mechanical, physical and thermal properties of biobased composite materials. It can be observed by tests such as indirect tensile strength, compressive strength for mechanical characteristics, density, shrinkage, color for physical properties, thermal conductivity and resistivity for thermal properties, and inundation test for durability of crude bricks. In this study, mechanical and physical characteristics of crude bricks reinforced with palm oil fibers are investigated and effect of change in percentage and length of fibers is observed. Crude bricks of size 4*4*16 cm3 are manufactured with dredged sediments from Usumacinta River, Mexico and reinforced with palm oil fibers at laboratory scale. For this purpose, sediments and palm oil fibers characteristics were studied. Length of fibers used is 2cm and 3cm. Bricks manufacturing steps such as sediments fibers mixing, moulding, compaction and drying are elaborated. Dynamic compaction is opted for compaction of crude bricks due to energy control. Indirect tensile strength and compressive strength tests are conducted to identify the mechanical characteristics of crude bricks. Physical properties of bricks are studied through density and shrinkage. Durability of crude bricks is observed with inundation test. Thermal properties are studied with thermal conductivity and resistivity test. Distribution and orientation of fibers and fibers counting are done to observe the homogeneity of fibers inside the crude bricks. Finally, comparison between the mechanical characteristics of crude bricks manufactured with 2cm and 3cm length with control specimen was made.


2021 ◽  
Vol 25 (Special) ◽  
pp. 2-72-2-77
Author(s):  
Hassanein M. Nhoo ◽  
◽  
Raad. M. Fenjan ◽  
Ahmed A. Ayash ◽  
◽  
...  

The current paper deals with investigating the effect of two different fillers on the thermal and mechanical characteristics of epoxy-based composite. The filler used throughout the study are: charcoal and Pyrex, both of them are different in nature and have not been investigated thoroughly or even compared fairly in terms of their effect on polymer matrix. Further, they can be considered as a cheap filler, charcoal can be obtained from a simple pyrolysis process of plants (charcoal) and Pyrex waste can be collected easily. Both types are added to the selected matrix with volume percent ranged from 10 to 60 with increments of 10. To ensure a fair comparison, the particle size is fixed (is about 1.7 micrometer). The results showed that the epoxy thermal conductivity has enhanced by about two orders of magnitudes over the studied range of filler. In terms of mechanical properties, the charcoal improves the tensile strength about 84% at 60% volume fraction while the Pyrex effect is about 40% at the same filler level. On the contrast, the results of compressive strength do not show an appreciable improvement overall. It decreases by about 12% at 60% volume fraction of charcoal while increases about the same percent with Pyrex at the same filler level.


2021 ◽  
Vol 25 (11) ◽  
pp. 36-41
Author(s):  
D.V. Bespolitov ◽  
N.A. Konovalova ◽  
O.N. Dabizha ◽  
P.P. Pankov ◽  
E.A. Rush

The possibility of utilization of inactive fly ash in road concrete compositions by bringing of ash into a non-equilibrium condition with increased reactivity by mechanical activation in a vibration eraser is investigated. It was revealed that the optimal content of binder and fly ash in samples of soil concrete was 8 and 10 wt. %, respectively. It is shown that, due to mechanical activation, the specific surface area of fly ash increases by 2 times, dehydration and carbonization occur and silicon is replaced by aluminum in silicon-oxygen tetrahedra. It has been established that an increase of the content of crystalline carbonate phases is the reason for an increase in the strength of ground concrete. It is determined that the introduction of mechanoactivated fly ash into the composition of soil concretes contributes to increasing their physical and mechanical characteristics to the maximum strength grade M100. This indicates the competitiveness of ground concrete and the possibility of direct use of inactive fly ash in road construction.


2018 ◽  
Vol 162 ◽  
pp. 02024
Author(s):  
Waleed Abbas ◽  
Wasan Khalil ◽  
Ibtesam Nasser

Due to the rapid depletion of natural resources, the use of waste materials and by-products from different industries of building construction has been gaining increased attention. Geopolymer concrete based on Pozzolana is a new material that does not need the presence of Portland cement as a binder. The main focus of this research is to produce lightweight geopolymer concrete (LWGPC) using artificial coarse lightweight aggregate which produced from locally available bentonite clays. In this investigation, the binder is low calcium fly ash (FA) and the alkali activator is sodium hydroxide and sodium silicate in different molarities. The experimental tests including workability, fresh density, also, the compressive strength, splitting tensile strength, flexural strength, water absorption and ultrasonic pulse velocity at the age of 7, 28 and 56 days were studied. The oven dry density and thermal conductivity at 28 days age are investigated. The results show that it is possible to produce high strength lightweight geopolymer concrete successfully used as insulated structural lightweight concrete. The 28-day compressive strength, tensile strength, flexural strength, dry density, and thermal conductivity of the produced LWGPC are 35.8 MPa, 2.6MPa, 5.5 MPa, 1835kg/m3, and 0.9567 W/ (m. K), respectively.


2018 ◽  
Vol 14 (1) ◽  
pp. 126-135
Author(s):  
Reza Mirzaei ◽  
Naser Zarifmoghaddam

 Concrete as the most used material, is known as an integral part of construction. So far, many studies have been done in the field of improving the quality of concrete that most of them have examined change in concrete mix which is called concrete mix plan. However, the use of additives and also replacing commonly used materials in concrete with new materials always has been noteworthy. In this study, description of tests that have been done on fiber reinforced concrete will be discussed. Also, the condition of concrete mix plan will be discussed. Comparison between results of the tests showed that Forta reinforced concretes have more compressive, flexural and tensile strength and modulus of elasticity than normal and ordinary concretes.Journal of the Institute of Engineering, 2018, 14(1): 126-135 


2020 ◽  
Vol 11 (3) ◽  
pp. 101-105
Author(s):  
Daria A. Kalabina ◽  
Grigorij I. Yakovlev ◽  
Zdenek Dufek ◽  
Grigoriy N. Pervushin ◽  
Kirill A. Bazhenov ◽  
...  

The influence of a plasticizer based on polycarboxylate esters on the properties of a high-strength fluoroanhydrite composition and a lightweight composition with expanded perlite sand is investigated. It was shown that the addition of 2% polycarboxylate esters on water base to compositions has increased compressive strength and a flexural strength up to 46% and 20% respectively compare to composite without any additives. Due to the structure’s compaction of the compositions, water absorption decreased and the water resistance of the material increased. Microstructural analysis of the compositions confirmed the improvement of physical and mechanical characteristics by changing the morphology of crystallohydrate formations, increasing the contact area between new formations and modifying the structure by carbon nanotubes. The developed mixtures are supposed to be apply for self-leveling fluid mixtures for floors with reduced thermal conductivity.


2020 ◽  
Vol 26 (3) ◽  
pp. 173-180
Author(s):  
LUCIAN PAUNESCU ◽  
MARIUS FLORIN DRAGOESCU ◽  
SORIN MIRCEA AXINTE

The paper presents recent achievements in the microwave use for manufacturing foam glass gravel from recycled glass waste and silicon carbide. The aim was to obtain a product with physical and mechanical characteristics almost similar to those of industrially manufactured materials by conventional heating techniques, but with a higher energy efficiency. A foam glass with the thermal conductivity of 0.075 W/m·K and the compressive strength of 7.5 MPa was experimentally obtained. The specific energy consumption was of 1.0 kWh/kg comparable with the industrial processes and it could reach values up to 25% lower by using a high power industrial microwave equipment.


2021 ◽  
Vol 316 ◽  
pp. 1025-1030
Author(s):  
Yuri M. Kosichenko ◽  
Oleg Andreevich Baev ◽  
Sergey Mikhailovich Vasilyev

The article deals with the «GP» geo-composite drainage material, which is used in hydro-technical, civil, as well as environmental, industrial and landscape construction. This material is intended for complex application, as a separating, filtering and reinforcing layer in the structures of protective dams on rivers, reservoirs, channels, an earth work of linear transport constructions (automobile and railway facilities) and other hydraulic engineering constructions. It is a combined geo-synthetic material, including a rigid geo-grid of the lattice structure and a filtering geotextile element. As a result of the carried out researches, its basic physical and mechanical characteristics have been established: tensile strength, surface density of geotextile and the material, relative elongation at maximum load, filtration coefficient normal to the material level.


Sign in / Sign up

Export Citation Format

Share Document