scholarly journals Soil-concrete for use in the 3D printers in the construction of buildings and structures

2018 ◽  
Vol 245 ◽  
pp. 03002 ◽  
Author(s):  
Petr Iubin ◽  
Lubov Zakrevskaya
Keyword(s):  
Rheological Properties ◽  
Cement Paste ◽  
Clay Soil ◽  
Cement Composite ◽  
Cement Composites ◽  
Test Results ◽  
Flow Table ◽  
Key Factor ◽  
3D Printers ◽  
The Cost

Nowadays, the construction of cement composite using 3D printers is considered one of the most promising methods of automation of building processes. However, the compositions of cement composites have several disadvantages, such as high cost, short workability and etc. It has been suggested that clay soil as an additive will help to solve these problems partially. The aim of the work is development the cement compositions with clay soil, for use in 3D printers to construction. The composite consists of cement paste with clay soil and additives. To study printability of a composite the rheological properties in a fresh state were studied. The study of the rheological properties of composites was carried out using a flow table test for mortar. The key factor for determining the suitability of the composite for printing was accepted the diameter of the cone after shaking. The test results showed the possibility of replacing cement paste with clay soil up to 25% which leads to a reduction in the cost and an increase in printability with a slight decrease in the strength of the obtained material to 7%. Utilizing of soil from the construction site provides maximum economic efficiency of the material application.

scholarly journals Damping Property of a Cement-Based Material Containing Carbon Nanotube

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Wei-Wen Li ◽  
Wei-Ming Ji ◽  
Yi Liu ◽  
Feng Xing ◽  
Yu-Kai Liu
Keyword(s):  
Carbon Nanotube ◽  
Cement Paste ◽  
Load Transfer ◽  
Cement Composite ◽  
Mechanical Analysis ◽  
Cement Matrix ◽  
Cement Composites ◽  
Strength Index ◽  
Damping Property ◽  
Reduction Capacity

This study aimed to explore the damping property of a cement-based material with carbon nanotube (CNT). In the study, the cement composites with different contents of CNT (0 wt%, 0.033 wt%, 0.066 wt%, and 0.1 wt%) were investigated. Logarithmic Decrement method and Dynamic Mechanical Analysis (DMA) method were utilized to study the damping property of CNT/cement composite. The influences of CNT on pore size distribution and microstructure of composite were analyzed by Mercury Intrusion Porosimetry (MIP) and Scanning Electron Microscopy (SEM), respectively. The experimental results showed that CNT/cement composite presented higher flexural strength index than that of a pure cement paste. Additional CNT could improve the vibration-reduction capacity of cement paste. Furthermore, the experiments proved that CNT could bridge adjacent hydration products and support load transfer within cement matrix, which contributed to the energy dissipation during the loading process.

Effect of Mineral Admixtures on Rheological Properties of Cement Paste

2014 ◽  
Vol 936 ◽  
pp. 1409-1413 ◽  
Author(s):  
Lin Chun Zhang ◽  
Ai Lian Zhang
Keyword(s):  
Fly Ash ◽  
Rheological Properties ◽  
Silica Fume ◽  
Cement Paste ◽  
Reducing Agent ◽  
Mineral Admixtures ◽  
Test Results ◽  
Optimal Ratio ◽  
Mix Proportion

The Marsh cone method and rotary viscosimeter are used to study the effect of mineral admixtures such as ultra-fine fly ash, ultra-fine slag, zeolite powder and silica fume on rheological properties of cement paste. Test results show that the optimal ratio of ultra-fine fly ash, ultra-fine slag, zeolite powder and silica fume are respectively 20%, 20%, 10% and 8%. And the optimized mix proportion is the composition of 8% silica fume and 12% slag. By using water reducing agent and mineral admixtures we could get the cement paste which has good liquidity and no bleeding.

scholarly journals Efficient Use of Graphene Oxide and Silica Fume in Cement-Based Composites

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6541
Author(s):  
Ahmad Abdullah ◽  
Mohamed Taha ◽  
Mohamed Rashwan ◽  
Mohamed Fahmy
Keyword(s):  
Graphene Oxide ◽  
Silica Fume ◽  
Cement Composite ◽  
Mix Design ◽  
Design Parameters ◽  
Cement Matrix ◽  
Cement Composites ◽  
Test Results ◽  
Main Criterion ◽  
Simplified Approach

Incorporation of graphene oxide (GO) and silica fume (SF) to cement composites enhances their mechanical properties if suitable proportional amounts of GO and SF are used. This study presents a simplified approach to determine experimentally the optimum GO and SF contents that should be added to the cementitious mixture to obtain a proper and stable dispersion of GO sheets within the cement matrix. Composite mortar specimens with different GO and SF contents were designed and tested under flexural and compression loading. The phase formation and the microstructure of selected samples were also investigated to give an in-depth interpretation of the test results. The main criterion to determine the GO and SF contents was the ultimate strength required of the GO–cement composite. It was found that there was a composite interaction between the SF and GO contents in the cementitious mixture, which an envelope surface could describe if all other mix design parameters are kept constant.

scholarly journals On the Fresh/Hardened Properties of Cement Composites Incorporating Rubber Particles from Recycled Tires

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Alessandra Fiore ◽  
Giuseppe Carlo Marano ◽  
Cesare Marti ◽  
Marcello Molfetta
Keyword(s):  
Cement Composite ◽  
Cement Composites ◽  
Test Results ◽  
Freezing And Thawing ◽  
Chloride Permeability ◽  
Fine Aggregates ◽  
Rubber Particles ◽  
Suitable Amount ◽  
Hardened Properties ◽  
Rubberized Mortar

This study investigates the ameliorative effects on some properties of cement-based materials which can be obtained by incorporating rubber particles as part of the fine aggregates. The aim is to find out optimal cement composite/mortar mixtures, containing recycled-tyre rubber particles, suitable for specific engineering applications. Different percentages of rubber particles, from 0% to 75%, were used and, for each percentage, the suitable amount of sand was investigated in order to achieve the best fresh/hardened performances. In particular the following characteristics were examined: density, compressive strength, modulus of elasticity, shrinkage, weight loss, flexural behaviour, thermal conductivity, rapid freezing and thawing durability, and chloride permeability. The experimental results were compared with the ones of cement composite specimens without rubber aggregates. Test results show that the proposed rubberized mortar mixes are particularly suitable for some industrial and architectural applications, such as under-rail bearings, road constructions, paving slabs, false facades, and stone backing.

scholarly journals Foundation Piles—A New Feature for Concrete 3D Printers

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2545
Author(s):  
Marcin Hoffmann ◽  
Krzysztof Żarkiewicz ◽  
Adam Zieliński ◽  
Szymon Skibicki ◽  
Łukasz Marchewka
Keyword(s):  
3D Printing ◽  
Rapid Development ◽  
Construction Materials ◽  
Shallow Foundation ◽  
Soil Reinforcement ◽  
3D Printer ◽  
Permanent Formwork ◽  
3D Printers ◽  
New Feature ◽  
The Cost

Foundation piles that are made by concrete 3D printers constitute a new alternative way of founding buildings constructed using incremental technology. We are currently observing very rapid development of incremental technology for the construction industry. The systems that are used for 3D printing with the application of construction materials make it possible to form permanent formwork for strip foundations, construct load-bearing walls and partition walls, and prefabricate elements, such as stairs, lintels, and ceilings. 3D printing systems do not offer soil reinforcement by making piles. The paper presents the possibility of making concrete foundation piles in laboratory conditions using a concrete 3D printer. The paper shows the tools and procedure for pile pumping. An experiment for measuring pile bearing capacity is described and an example of a pile deployment model under a foundation is described. The results of the tests and analytical calculations have shown that the displacement piles demonstrate less settlement when compared to the analysed shallow foundation. The authors indicate that it is possible to replace the shallow foundation with a series of piles combined with a printed wall without locally widening it. This type of foundation can be used for the foundation of low-rise buildings, such as detached houses. Estimated calculations have shown that the possibility of making foundation piles by a 3D printer will reduce the cost of making foundations by shortening the time of execution of works and reducing the consumption of construction materials.

scholarly journals The Influence of Chosen Factors on the Rheological Properties of Cement Paste

2015 ◽  
Vol 108 ◽  
pp. 568-574 ◽  
Author(s):  
Alina Kaleta ◽  
Stefania Grzeszczyk
Keyword(s):  
Rheological Properties ◽  
Cement Paste

Mechanical Behavior of Ti-6Al-4V Manufactured by Electron Beam Additive Fabrication

2013 ◽  
Author(s):  
Leila Ladani ◽  
Lalit Roy
Keyword(s):  
Mechanical Properties ◽  
Electron Beam ◽  
Lead Time ◽  
Aerospace Industry ◽  
Tensile Tests ◽  
Test Results ◽  
Great Resistance ◽  
Additive Fabrication ◽  
Anisotropy Effect ◽  
The Cost

Additive Layer Fabrication, in particular Electron Beam Additive Fabrication (EBAF), has recently drawn much attention for its special usability to fabricate intricately designed parts as a whole. It not only increases the production rate which reduces the production lead time but also reduces the cost by minimizing the amount of waste material to a great extent. Ti6Al4V is the most common type of material that is currently being fabricated using EBAF technique. This material has been used in aerospace industry for several reasons such as excellent mechanical properties, low density, great resistance to corrosion, and non-magnetism. The effects of build direction of layers (namely, addition of layers along one of the x, y & z directions with respect to the build table) and the anisotropy effect caused by it has not been explored vigorously. This anisotropy effect has been investigated in this work. Different mechanical properties such as Yield Strength (YS), Ultimate Tensile Strength (UTS), and Modulus of Elasticity (E) of these three types of Ti6Al4V are determined using tensile tests and are compared with literature. The tensile test results show that YS and UTS for flat-build samples have distinguishably higher values than those of the side-build and top-build samples.

Experimental Research on the Engineering Properties of Foam-Improved Red Clay Soil

2011 ◽  
Vol 261-263 ◽  
pp. 1831-1835
Author(s):  
Guo Gang Qiao ◽  
Da Jun Yuan ◽  
Bo Liu
Keyword(s):  
Experimental Research ◽  
Clay Soil ◽  
Soil Improvement ◽  
Engineering Properties ◽  
Screw Conveyor ◽  
Test Results ◽  
X Ray Diffraction ◽  
Shield Tunneling ◽  
Red Clay ◽  
Improvement Measures

Red clay soil is widely distributed in south China, the microstructure of red clay soil was studied applying scanning electron microscopy (SEM), and the X-ray diffraction analysis (XRD) test found that a large number of swelling inducing minerals, for example, montmorillonite, illite-montmorillonite or chlorite-smectite were contained in the red clay soil. Shield tunneling in this kind of stratum is prone to arising “cake” and “arch” phenomena and it prone to lead screw conveyor device unsmooth dumping, so soil improvement measures must be taken. Foam as the most advanced soil conditioner has been widely used in shield construction. Using self-developed foam agent, experimental research on foam conditioning red clay soil was carried out, test results show that foam can not only significantly reduce the soil shear strength, but also can greatly enhance the soil's compressibility and fluidity, which is significant for the smooth dumping and excavation face stability maintenance.

From a Seed to a Need: the Growth of Shape Memory Applications in Europe.

1991 ◽  
Vol 246 ◽  
Author(s):  
Ir. J. Van Humbeeck
Keyword(s):  
Shape Memory ◽  
Low Cost ◽  
Marketing Research ◽  
Research Approach ◽  
Manufacturing Cost ◽  
Product Price ◽  
Key Factor ◽  
Place Promotion ◽  
Memory Applications ◽  
The Cost

AbstractA more systematic marketing research approach has finally revealed good ideas anticipating a market need for the use of shape memory alloys. The success of those new ideas, prototypes and applications are analysed in terms of “the value of the function”, defined as the importance of the function divided by the cost of providing the function. A high importance and/or a low cost of the function are thus the basic requirements for the successful introduction of shape memory applications. Attention is also paid to the way how the 4 P's, product, price, place, promotion (the marketing mix) are applied by the European companies. Those different items will be illustrated on the basis of some small-, medium- and largescale applications, used in different markets. “to the point research”, fundamental and applied, on material properties as well as on manufacturing (cost reduction) is being discussed as the key factor to increase the function value.

Research on Electrical Double Percolation of Carbon Black-Filled Cement-Based Composites

2011 ◽  
Vol 311-313 ◽  
pp. 201-204
Author(s):  
Hong Zhong Ru ◽  
Ran Ran Zhao
Keyword(s):  
Carbon Black ◽  
Cement Paste ◽  
Volume Fraction ◽  
Carbon Black Particle ◽  
Carbon Black Content ◽  
Percolation Behavior ◽  
Key Factor ◽  
Binder Ratio ◽  
Black Particle ◽  
Double Percolation

Electrical conductive carbon black-filled cement-based composites are significant as multifunctional structural materials. Double percolation in carbon black-filled cement-based composites involves both carbon black particle percolation and cement paste percolation, which has great effect on the resistivity of composites. Based on double percolation theory, the influences of sand-binder ratio and carbon black volume fraction on the resistivity of carbon black-filled cement-based composites are investigated. The results show that besides carbon black volume fraction, sand-binder ratio is a key factor affecting double percolation behavior in carbon black-filled cement-based composites. At a fixed carbon black content in overall mortar, with increasing sand-binder ratio, the cement paste percolation though aggregate phase increases due to high obstruction of aggregate but the carbon black particle percolation in cement paste decreases. This is because that the microstructure of aggregate is impenetrable so that the carbon black particles are limited in cement paste, that is, the carbon black content in paste is compacted and large amount of conductive paths are generated by lapped adjacent carbon black particles in paste. The double percolation in the electrical conduction in carbon black-filled cement-based composites is observed when the carbon black volume fraction is 7.5% and sand-binder ratio is 1.4, and its resistivity is only 3200 Ωcm, so that a sand-binder ratio of 1.4 and 7.5% carbon black volume fraction or more are recommended for attaining high conductivity with a compromise between workability and conductivity.

Sign in / Sign up

Export Citation Format

Share Document