2. ⢠Self-Healing Bio-Concrete. ⢠Carbon-Negative Concrete. ⢠Photovoltaic Glazing. ⢠Modular Construction. ⢠LF Thermosyphon. ⢠Geopolymer Concrete.
New Materials, Products, or Technologies for Construction
By
Dr. Md. Safiuddin and
Mr. Herman Durazno Flores
New Materials, Products, or Technologies for Construction Self-Healing Bio-Concrete
Carbon-Negative Concrete Photovoltaic Glazing Modular Construction LF Thermosyphon Geopolymer Concrete Transparent Concrete Hempcrete Block 2
Self-Healing Bio-Concrete Specially selected types of Self-healing bio-concrete biologically produces limestone to heal the the bacteria genus cracks of concrete structures Bacillus, along with a appeared under service conditions. calcium-based nutrient (calcium lactate plus Self-healing bio-concrete could solve nitrogen plus phosphorus) the problem of concrete structures are added to the deteriorating well before the end of ingredients of the their service life. concrete when it is being mixed. The self-healing agents can lie dormant within the bio-concrete for up to 200 Source: www.industrytap.com years. 3
Self-Healing Bio-Concrete Source: www.xprize.org
Crack
The cracked surface of a slab of self-healing bio-concrete
Sealed Crack
The crack has been sealed by white limestone product
In a self-healing bio-concrete, dormant bacterial spores contained in clay pellets (black and gray circles, left) germinate when cracks expose them to moisture. The microbes feed on calcium lactate form limestone to seal the cracks (right). 4
Carbon-Negative Concrete Cement-free, carbon impounding concrete – permanently sequesters CO2. No emission but injection of CO2 – Hence, “CarbonNegative”. Slag, a by-product of steel industry is the primary binder (slag plus silica-rich material can also be used). CO2 (it can be sourced from power plant) is injected into concrete through carbonation activation to give strength to concrete with carbonate bonding (after reacting with oxide, hydroxide, and silicate components of the binder material). 5
Carbon-Negative Concrete Less expensive (lower materials cost), more durable, and more environment-friendly.
Can be used to produce many concrete products such as concrete masonry units.
Equivalent mechanical properties as compared to regular concrete. This technology would be very conducive to solve CO2 related environmental problems.
Ref: Heather Clancy, “The quest to create carbon-negative concrete”, GreenBiz, https://www.greenbiz.com 6
Photovoltaic Glazing Photovoltaic glass (PV glass) is a technology that enables the conversion of light into electricity. To do so, the glass incorporates transparent semiconductor based photovoltaic cells, which are also known as solar cells. The cells are sandwiched between two sheets of glass (or an outer sheet of glass plus and a backing sheet of other material).
Photovoltaic glass is not perfectly transparent but allows some of the available light through (if the backing sheet is transparent).
Source: EnergyGlass 7
Photovoltaic Glazing Buildings using a substantial amount of photovoltaic glass could produce some of their own electricity through the PV windows. The PV power generated is considered green electricity because its source is renewable and it does not cause pollution. In addition to energy cost savings, potential benefits from the use of photovoltaic glass include reducing the carbon footprint of facilities, contributing to sustainable development.
Source: switchedonkids.com.au 8
Modular Construction Modular construction is a process in which building parts are made off-site, under controlled plant conditions, using the same materials and designing to the same codes and standards as conventionally built facilities. Buildings are produced in “modules” that come together on site. Source: berrysmith.com
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Modular Construction Structurally, modular buildings are stronger than conventional buildings because each module is engineered to independently withstand the rigors of transportation and craning onto foundations. Once together and sealed, the modules become one integrated wall, floor and roof assembly. Building off site ensures better construction quality management.
Source: Pavel Podolyak, “Modular Apartment Buildings”, The Pragmatist, August 1, 2012
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LF Thermosyphon A group of scientists from Wilfrid Laurier University, Waterloo, Ontario, Canada has developed a new, simplified patent-pending design for a “liquid-filled thermosyphon with forced circulation” (“LF thermosyphon”), for use in the Canadian Arctic region. LF thermosyphon mainly consists of a pipe, which is buried into the ground with the upper part exposed to the air. The pipe is filled with a liquid coolant. Source: Adventus Research + Consulting 11
LF Thermosyphon A low power pump operated by solar energy is used to produce the flow of coolant inside the thermosyphon. The pump automatically starts when the air temperature drops below 0°C. The circulating coolant inside the LF thermosyphon removes heat from the surrounding ground until it freezes. LF thermosyphons could be installed for preventing permafrost from melting, thus improving ground stabilization under an infrastructure element (road, building, etc.).
Source: Adventus Research + Consulting
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Concluding Remarks As research and development leads the way to new innovative ways to build using existing and new construction materials, products, or technologies, the industry will need well-equipped and well-versed human resources in these new inventions to better procure, manage and construct the new facilities of the 21st century. Skilled knowledge shall be required to apply new materials, products, and technologies in different construction sectors.
More New Materials, Products, or Technologies for Construction Geopolymer Concrete
Transparent Concrete Hempcrete Block
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Geopolymer Concrete Cement-free, eco-friendly concrete.
Geopolymer eliminates the use of portland cement, which is responsible for high CO2 emission. Slag and fly ash obtained as industrial by-product or waste and thermally activated natural materials such as kaolinite are used as the primary binder. Source: https://theconstructor.org/concrete/
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Geopolymer Concrete Alkaline activator solution (alkali silicate and alkali hydroxide) polymerizes the binder material into molecular chains or networks to create geopolymer that binds the aggregates in concrete. 1-day strength: more than 25 MPa; 28-day strength: up to 60 to 70 MPa. “Low” to “Very Low” chloride permeability → High Durability.
Source: https://theconstructor.org/concrete/
The University of Queensland’s Global Change Institute (GCI)
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Transparent Concrete “See-through” concrete with optical fibres;
Source: intermasz.pl
It can be produced as prefabricated building blocks and panels. Thousands of optical strands are placed in concrete to transmit light, either natural or artificial, through the translucent (semi-transparent) concrete panels. 17
Transparent Concrete Optical glass fibers running in concrete matrix do not affect the strength of concrete. It is frost- and deicing saltresistant. It provides adequate fire protection and possesses high UV resistance. May fulfill the purpose of glazing. Can allow daylight, thus reducing the need for artificial lighting → energy efficiency.
Source: pinterest.ca
Italy Pavilion - Expo 2010 Shanghai China
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Hempcrete Hempcrete is a sustainable, energy-efficient building material. Hemp is derived from the Marijuana plant. The stalk of the male Marijuana plant is finely chopped into hemp curds, which are mixed with water and lime to produce a concrete-like material. The male plant is used because it does not contain any psychoactive compound found primarily in the female plant.
Source: The Western Producer
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Hempcrete Hempcrete is a lightweight, non-toxic, biodegradable, fire-proof, rot-proof, moldresistant, and breathable building material. A potential material for green building construction. This material can be used to produce building products or elements in the form of masonry blocks, walls, slabs, roof tiles, and insulation panels.
Source: Italianprojectsonline.com
Source: thelaststraw.org 20
