Graphene-Based Cement/Concrete Admixture for Ultra-Strong, High-Strength and Sustainable Housing/Infrastructure
It has been over a decade since graphene (a single layer sheet of graphite) was first discovered, but this wonder-material continues to make headlines almost every day, thanks to its extraordinary properties. Since year 2010, this wonder material graphene has inspired great interest among industrialists and entrepreneurs in regard to many possible applications, including development of ultra-thin electronics, high performance battery and supercapacitors, polymeric composites and more. In this article, we will demonstrate how this 21st century super-advanced material could be used to develop ultra-strong, high strength housing and infrastructure in the U.S. and around the world. Employing this material could mitigate damage from cyclones, earthquakes and wildfires, saving lives and resources required for reconstruction. The best possible way to apply this highly-advanced material is to develop new composite cement and concrete admixture and use this composite admixture to build ultra-strong housing, buildings and infrastructure.
Before we discuss possibility of applying graphene-based materials to develop ultra-strength cement and concrete composite materials, it is important to become acquainted with the fascinating qualities of this amazing substance.
Graphene is a carbon allotrope, appearing on the atomic level as a 2-D hexagonal lattice, a sheet-like layer of graphite. It is the fundamental building block of other carbon allotropes such as graphite and charcoal. Graphene is roughly 200 times stronger than the high-grade steel, all while conducting heat and electricity and appearing virtually transparent. At room temperature, the electrical and thermal conductivities are ~1.00×10 8 S/m and ∼5300 W/m.K. Graphene has density as low as 1.5-2.0 g/cm 3 , high modulus of elasticity (Young’s modulus: ~1.10 TPa, Tensile strength: ~130 GPa), good resistance to deformation, stretchable by 20-30 %. Spring constants are in the region of 1-5 N/m. Also, graphene is thermally and chemically stable up to 600-degree temperature at ordinary atmospheric pressure. As new properties are unveiled, application prospects for this 21st century material widen day by day, surprising us in many ways. In this report, we demonstrate how graphene based materials can be used to develop ultra-strong, highly-durable houses, buildings and infrastructure.
In the wake of the devastating hurricanes Harvey and Irma, it has become necessary to devote much attention to developing buildings, houses and infrastructure capable of withstanding from much stronger hurricane and earthquakes. We have all seen the devastating effects of hurricane Irma and it is time to step up and think about upcoming natural disasters and to prepare ourselves. Since long ago, scientists are constantly working on developing much better and stronger building materials. Scientists have discovered a large number of materials, but nothing has inspired more optimism than this super material graphene. Graphene has already proven its potential in many ways. Graphene has been applied to develop super strong composite materials with metallic alloys, consisting of copper and nickel. Graphene has been applied to develop ultra-strong glass composite, etc. Graphene (produced from naturally available graphite) possesses the required properties to develop such ultra-strong, high strength and flexible building materials.
There are hundreds of available scientific research findings in this field which have demonstrated positive amplified reinforcement effects. The process of developing graphene-incorporated cement and concrete composite admixtures is relatively easy and simple. A revolutionary application is that the addition of graphene to cement creates a stronger and greener environmentally friendly concrete. The addition of graphene addition also shortens curing times; decreases the amount of cement mixture required during construction, provides superior performance, prevents premature failure and is able to withstand the great stresses caused by explosions and earthquakes.
Researchers from Australia have developed a graphene-cement matrix with enhanced strength and durability through the incorporation of graphene oxide (GO). They mixed 0.05 to 0.07 wt.% of GO with Ordinary Portland Cement (OPC) and tested various parameters as highlighted. Tested results showed improvement flexural strength of an OPC matrix from 41% to 59% and compressive strength from 15% to 33%. The addition of GO also increases ductility while decreases the probability of abrupt failure of the concrete. Furthermore, GO-OPC samples display a much broader stress-strain curve within the post-peak zone. The research group also have mentioned that adding GO improves pore structure and decreases total porosity from 32.6% to 28.2%, resulting in superior compressive strength and greater durability in the finished product. The addition of GO facilitates optimal hydration of the cement paste and increases the density of the cement matrix, which toughens the overall structure.
There are other research institutes and research centers that have published a great number of reports on this, scientists have carried out research using different types of graphene-based materials, summarizing that graphene could be a great alternative to develop advanced cement and concrete composite admixture. Researchers from China have published findings on functionalized graphene nanosheets (FGN)-cement composites playing a role in the composition of mortars. They have studied flow properties, mechanical properties and microstructure of the cement material. FGN’s favorable influence on the end product includes a moderate decrease in the fluidity of the composite mixture, as well as a significant improvement in its mechanical properties. Researchers have optimized for maximum strength by setting FGN content at 0.02%, resulting in the flexural and compressive strength at 28 days of 12.917 MPa and 52.42 MPa, respectively. Moreover, scanning electron microscope (SEM) analysis shows that FGN could impact the appearance of massive compact cross-linking structures. The thermogravimetric analysis demonstrates the hydration reaction was accelerated to a great extent, leading to a concomitant improvement in functionality for the cement composite. There are a number of similar studies that have been carried out by different research institutes. Their research findings are widely available.
In the past, mass production of graphene and graphene-based materials was a challenge, but recently that issue has been almost resolved. There are many companies around the world including, NanoGraphene Inc., which have developed scaled-up production facilities. However, this scaled-up mass production facility is not in full operation mode and is expected to be ready in coming months. Our current monthly production quantity is 6 tons and will reach far more in coming months. Currently we are producing high quality pristine graphene, with 1 to 10 layers. We are involved with different R&D projects with many companies around the world. We would be happy to provide you a free graphene sample upon request. We would also provide you the necessary technological and R&D supports. Contact us for free sample; we are looking forward to hearing from you.
Author: Dr. Jay Mondal is the head of R&D department at Nano Graphene.
Sources and Further Reading
The concrete that heals its own cracks (www.weforum.org)
Graphene oxide reinforced concrete (www.monash.edu.au)
Graphene Makes Concrete Stronger ( www.concreteconstruction.net)
Nano reinforced cement and concrete composites and new perspective from graphene oxide (DOI: 10.1016/j.conbuildmat.2014.09.040)
Effect of graphene on mechanical properties of cement mortars (DOI: 10.1007/s11771-016-3139-4)
Investigation of Physical Properties of Graphene-Cement Composite for Structural Applications (DOI:10.4236/ojcm.2014.41002)
Reinforcing Effects of Graphene Oxide on Portland Cement Paste (DOI: 10.1061/(ASCE)MT.1943-5533.0001125)
Properties of Cement Mortar and Ultra-High Strength Concrete Incorporating Graphene Oxide Nanosheets (10.3390/nano7070187)
Mechanism of cement paste reinforced by graphene oxide/carbon nanotubes composites with enhanced mechanical properties (DOI: 10.1039/c5ra18602a)