Effect of synthetic microfiber and viscosity modifier agent on layer deformation, viscosity, and open time of cement mortar for 3D printing application

3D-printing of cementitious materials is an innovative construction approach with which building elements can be constructed without the use of formwork. Despite potential benefits in the construction industry, it introduces various engineering challenges from the material point of view. This paper reviews the properties of extrusion-based 3D-printed cementitious materials in both fresh and hardened states. Four main properties of fresh-state printing materials are addressed: flowability, extrudability, buildability, and open time, along with hardened properties, including density, compressive strength, flexural strength, tensile bond strength, shrinkage, and cracking. Experimental testing and effective factors of each property are covered, and a mix design procedure is proposed. The main objective of this paper is to provide an overview of the recent development in 3D-printing of cementitious materials and to identify the research gaps that need further investigation.

Download Full-text

Study of the Residual Length of Discrete Carbon Fibers in Polyetherimide Based Composites for 3D-Printing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.899.309 ◽

2021 ◽

Vol 899 ◽

pp. 309-316

Author(s):

Ismel V. Musov ◽

Azamat L. Slonov ◽

Azamat A. Zhansitov ◽

Zhanna I. Kurdanova ◽

Svetlana Yu. Khashirova

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Carbon Fibers ◽

Physical And Mechanical Properties ◽

Melt Viscosity ◽

Viscosity Modifier ◽

Fibrous Filler ◽

Linear Dimensions ◽

Filler Particles ◽

Filled Composite

The influence of the multiplicity of extrusion and melt viscosity on the residual length of discrete carbon fibers in composites based on polyetherimide for 3D-printing is estimated. A technique for measuring the residual length of carbon fibers in composites is proposed. The residual length of carbon fibers in composites containing from 10 to 40% fibrous filler with different initial linear dimensions has been determined. It was found that the addition of a melt viscosity modifier to a carbon-filled composite helps to maintain the linear dimensions of the fiber filler particles, thereby increasing the physical and mechanical properties of the material.

Download Full-text

Specification of the Properties and Effects of Additives and Admixtures on a Mixture Suitable for 3D Printing of Buildings

Slovak Journal of Civil Engineering ◽

10.2478/sjce-2020-0029 ◽

2020 ◽

Vol 28 (4) ◽

pp. 38-44

Author(s):

Diana Fiľarská ◽

Stanislav Unčík ◽

Terézia Cabanová

Keyword(s):

3D Printing ◽

Cement Mortar ◽

Fresh Mixture ◽

The World ◽

Optimal Mix

AbstractThis article focuses on 3D printing of buildings using cement mortar-based material. Specific requirements are necessary for such a material; it therefore must have different properties compared to conventional cement mortar. These properties of a fresh mixture and the possibilities for their testing are described in more detail in the first part of the article. Specifically, these are pumpability, printability, buildability, and workability. In order to achieve these properties, it is necessary to add various additives and admixtures to the mixtures, in addition to the basic components such as water, sand, and cement. Scientists around the world are working to create an optimal mix. The second part of this article presents an overview of the most commonly used ingredients and their effect on the properties of the mixture.

Download Full-text

Post-processing Techniques to Enhance Strength of Portland Cement Mortar Digitally Fabricated Using Powder-Based 3D Printing Process

RILEM Bookseries - Rheology and Processing of Construction Materials ◽

10.1007/978-3-030-22566-7_53 ◽

2019 ◽

pp. 457-464

Author(s):

Ming Xia ◽

Behzad Nematollahi ◽

Jay Sanjayan

Keyword(s):

3D Printing ◽

Portland Cement ◽

Cement Mortar ◽

Post Processing ◽

Printing Process ◽

Processing Techniques

Download Full-text

Dynamic Properties and Fractal Characteristics of 3D Printed Cement Mortar in SHPB Test

Materials ◽

10.3390/ma14195554 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5554

Author(s):

Yixin Mo ◽

Songlin Yue ◽

Qizhen Zhou ◽

Bowei Feng ◽

Xiao Liu

Keyword(s):

Compressive Strength ◽

Fractal Dimension ◽

Energy Dissipation ◽

3D Printing ◽

Cement Mortar ◽

Dynamic Properties ◽

3D Printed ◽

Fractal Characteristics ◽

Dynamic Compressive Strength ◽

Printing Direction

Comparing with the traditional construction process, 3D printing technology used in construction offers many advantages due to the elimination of formwork. Currently, 3D printing technology used in the construction field is widely studied, however, limited studies are available on the dynamic properties of 3D printed materials. In this study, the effects of sand to binder ratios and printing directions on the fractal characteristics, dynamic compressive strength, and energy dissipation density of 3D printed cement mortar (3DPCM) are explored. The experiment results indicate that the printing direction has a more significant influence on the fractal dimension compared with the sand to binder ratio (S/B). The increasing S/B first causes an increase and then results in a decline in the dynamic compressive strength and energy dissipation of different printing directions. The anisotropic coefficient of 3DPCM first is decreased by 20.67%, then is increased by 10.56% as the S/B increases from 0.8 to 1.4, showing that the anisotropy is first mitigated, then increased. For the same case of S/B, the dynamic compressive strength and energy dissipation are strongly dependent on the printing direction, which are the largest printing in the Y-direction and the smallest printing in the X-direction. Moreover, the fractal dimension has certain relationships with the dynamic compressive strength and energy dissipation density. When the fractal dimension changes from 2.0 to 2.4, it shows a quadratic relationship with the dynamic compressive strength and a logarithmic relationship with the energy dissipation density in different printing directions. Finally, the printing mortar with an S/B = 1.1 is proved to have the best dynamic properties, and is selected for the 3D printing of the designed field barrack model.

Download Full-text

High Temperature Pore Properties of Polymer Cement Mortar for 3D Printing Using EVCL Redispersible Polymer Powder

Journal of the Korean Society for Advanced Composite Structures ◽

10.11004/kosacs.2019.10.6.054 ◽

2019 ◽

Vol 10 (6) ◽

pp. 54-61

Author(s):

Song Hun ◽

Shin HyeonUk

Keyword(s):

High Temperature ◽

3D Printing ◽

Cement Mortar ◽

Polymer Powder ◽

Pore Properties ◽

Redispersible Polymer Powder

Download Full-text

TRANSITION FROM TRADITIONAL COB CONSTRUCTION TO 3D PRINTING OF CLAY HOMES

Journal of Green Building ◽

10.3992/jgb.16.4.3 ◽

2021 ◽

Vol 16 (4) ◽

pp. 3-28

Author(s):

Amnah Y. Alqenaee ◽

Ali M. Memari ◽

Maryam Hojati

Keyword(s):

3D Printing ◽

State Of The Art ◽

Cementitious Materials ◽

Earth Construction ◽

Current State ◽

Time Period ◽

Open Time ◽

Specific Objective ◽

Computer Controlled ◽

Advanced Computer

ABSTRACT 3D printing of cementitious material can provide an affordable, sustainable, and optimized approach for the construction of homes, without compromising quality or craftsmanship. While most of the current research and development efforts in this field are focused on cement-based concrete printing, this paper focuses on the current state-of-the-art literature review of designing and developing a sustainable clay-based mixture design that mainly includes clay, sand, straw, lime, and water. The goal of this paper is to bridge the gap between typical traditional earth construction, specifically cob construction, and emerging 3D printing of cementitious materials. The specific objective of this paper is to offer some possible changes in the typical cob mixture so that it can be used for 3D printing of clay-based mixtures with sufficient flowability, buildability, strength, and open time (i.e., the time period between printing of one layer and printing of another layer deposited on a layer below). The paper describes typical clay-based mixtures and their traditional process and then specifies the challenges in going from traditional cob construction to advanced computer-controlled robotic 3D printing.

Download Full-text