< PreviousDEC 2023 - JAN 2024 10Written by Karen Hawthorne T here is no question that concrete is a strong and enduring cornerstone of the construction industry. Just consider the Pantheon and Colosseum in Rome, testaments to the durability of one of man’s most widely used materials. 11 CONSTRUCTION IN FOCUS The composite of sand, aggregate (typically gravel or stones) and water would later be combined with steel rods or mesh to form reinforced concrete. This superpowered type of concrete became the basis for skyscrapers such as the Empire State Building, completed in 1931, and in a more advanced form, the 57-storey “Jenga tower” apartments in Lower Manhattan in 2016. When you look at the history of concrete, it is the founda- tion of modern development—not only putting roofs over our heads, but also taming nature with bridges across rivers and roads to travel on land with speed and ease. It was an inexpensive way to rebuild cities that were destroyed by fire bombs and nuclear warheads in the Second World War. It has provided structures for health care, energy, education, and industry around the world. And just think of the magnificence of sports stadiums like the retractable-roof AT&T Stadium, home of the Dallas Cowboys in Arlington, Texas. After water, concrete is the most used substance on the planet, with twice as much concrete used in construction as all other building materials combined, according to ScienceDirect . Its advantages as a construction material are numerous, includ- ing its high strength and low cost—but it does have down- sides. As our built environment replaces nature, the concrete becomes a hard second skin across fertile topsoil and former habitats for wildlife. What policymakers and environmentalists alike are most con- cerned about, though, is the production of concrete. Reports from the British think-tank Chatham House say the production accounts for between four and eight percent of global carbon dioxide emissions. Compared to other materials, only oil, coal, and gas are more of a threat to the environment as sources of greenhouse gases. During concrete manufacturing, large quantities of carbon dioxide are released, both as a chemical by-product of cement production and in the energy required to fuel these reactions. “If concrete was a country, it would be the third biggest emitter of CO 2 in the world,” says Michael Wise, Co-founder and Chief Technology Officer at revolutionary construction company Concrete4Change. His company provides just one example of the efforts being made to reduce concrete’s environmental impact. The Concrete4Change team is developing technology that creates net zero concrete at a cheaper cost, helping to reduce the need for expensive materials to move concrete innovation forward. DEC 2023 - JAN 2024 12Wise’s approach is to take full advantage of concrete’s ability to naturally absorb CO 2 , a process known as carbonation. His technology will “exploit this potential, enabling concrete to become the safest form of CO 2 sink in the world. Even after the demolition of concrete, there is no leakage of CO 2 ,” explains the Concrete4Change website . How exactly? The technology captures and utilizes CO 2 by min- eralizing it in the concrete with a proprietary, low-cost, absor- bent material that absorbs CO 2 from industrial processes. This carrier is mixed as an additive into the concrete mix, so you end up with well-controlled carbonation of concrete during the curing, boosting its strength and “locking up CO 2 .” “Our technology will help the construction industry to recycle its waste CO 2 emissions, reduce costs, and increase the lifespan of buildings,” says Wise, noting that it can be used on any site. “The only difference is that it is cheaper and more durable.” Concrete is clearly a primary focus for research and develop- ment as our built environment continues to expand and advance. Predicted population growth—to 9.7 billion in 2050, a jump of almost 2 billion—means that we will need more infra- structure to house and serve people while at the same time making sure we protect our natural resources. Indeed, sustainability is a driver across all industries for reasons that will become even more apparent in the next 20 years. “Sustainable development is a fundamental break that’s going to reshuffle the entire deck. There are companies today that are going to dominate in the future simply because they under- stand that,” said François-Henri Pinault, French businessman and thought leader, to the New York Times Style Magazine . This underscores one of the largest challenges to sustainability and protecting the planet: it often comes at the expense of profit. It is easier for businesses to uphold the status quo rather than make changes for the greater good. However, there is a growing wave of consumer sentiment that is pushing compa- nies to prioritize sustainability and ethical behaviour. So how do you make it possible and viable for construction companies to make change and adopt greener concrete? It’s a work in progress. MIT engineers in early 2023 discovered other alternative additives to transform concrete into an effective carbon sink. Introducing new materials into existing concrete manufactur- ing processes shows huge potential to reduce its carbon foot- print without diminishing concrete’s bulk mechanical proper- ties that architects and builders rely on. 13 CONSTRUCTION IN FOCUS The MIT approach intervenes in the very early formation of car- bonates during concrete mixing and pouring before the material sets. The study’s engineers note that this largely eliminates the det- rimental effects of carbon dioxide uptake after the material cures. The best part of the process is its simplicity. One inexpensive ingredient is added to the mix: sodium bicarbonate, otherwise known as baking soda. In lab tests, the MIT team showed that as much as 15 percent of the total amount of carbon dioxide that comes with cement production could be mineralized during these early stages—enough to make a significant dent in the material’s carbon impact. Another benefit is that the resulting concrete sets much more quickly without impacting its mechanical performance, creating efficiencies for productivity. In a business where time is money, that’s a big win. Formwork, for example, can be removed earlier, so it takes less time to complete a building or bridge. The composite, a mix of calcium carbonate and calcium silicon hydrate, “is an entirely new material,” says study author Admir Masic, MIT professor of civil and environmental engineering, as reported by MIT News . “Through its formation, we can double the mechan- ical performance of the early-stage concrete.” He adds that the research is ongoing to evaluate the concrete’s performance over the long term, but the discovery points to “an optimistic future for the development of carbon neutral construction materials.” The idea of early-stage concrete carbonation is not entirely new, the authors say, but their work demonstrates that the precur- ing capacity of concrete to sequester carbon dioxide has thus far been underestimated and underutilized. “A number of projects are underway to address the high carbon output of the concrete industry and the other significant resource it impacts: water.” Construction site of a sustainable Timber-concrete composite office building DEC 2023 - JAN 2024 14When we talk about the circular economy, concrete is also part of the discussion, with a number of projects underway to address the high carbon output of the concrete industry and the other signifi- cant resource it impacts: water. Concrete reportedly uses almost a tenth of the world’s industrial water use, and while concrete pro- ducers are not yet paying for water, they may soon be. Meanwhile, researchers from the University of Tokyo have devel- oped a new method of producing concrete without cement. Their technique represents another way for the construction industry to reduce its carbon emissions, and suggests the poten- tial for building on the Moon and Mars. We may be headed toward colonization sooner than we think, and experiments with lunar soil are revealing that growing food is possible and robot rovers could find, drill, and gather surface ice for water supply. Back on Earth, another issue facing the construction industry is the limited availability of suitable sand for concrete produc- tion, which researchers say requires a specific size distribution to provide the correct properties. “In concrete, cement is used to bond sand and gravel,” says lead author of the University of Tokyo study, Yuya Sakai. “Some researchers are investigating how more cement can be replaced with other materials, such as fly ash and blast furnace slag, to reduce CO 2 emissions, but this approach is unsustain- able because the supply of these materials is decreasing owing to reduced use of thermal power systems and increased use of electrical furnace steel,” as Chem Europe reports. Sakai’s team worked to produce the chemical tetra alkoxysi- lane from sand through a reaction with alcohol and a catalyst by removing water, which is a by-product of the reaction. “Our idea was to leave the water to shift the reaction back and forth from sand to tetra alkoxysilane, to bond the sand par- ticles with each other.” Water conservation, producing concrete without cement, tech- nology to capture CO 2 —innovation in the industry certainly holds promise. The concrete of tomorrow is shaping up to be part of the solution for greener, more sustainable living. Designed by Laura Pratt 15 CONSTRUCTION IN FOCUS “The philosophy behind brutalist architecture is rooted in the belief that architectural design should prioritize functionality, honesty, and social purpose.” -Mark Bittoni, Bittoni Architects DEC 2023 - JAN 2024 16Written by Allison Dempsey L ove it or hate it—and the divisive reaction is strong— brutalist architecture remains one of the most conten- tious architectural movements of the modern era, fre- quently evoking strong feelings of both like and dislike. Brutalist architects promoted socialist utopian ideals which were often linked to the style, along with its simple and stripped bare aes- thetic of unpainted concrete or brick, along with steel, timber, and glass. Emerging in the 1950s after the second World War with simple structures many claimed were meant to house and provide shelter, brutalism particularly featured the recycling of concrete materials, which was one of the driving forces behind the movement. In fact, the word brutal- ism comes from the French “béton brut,” meaning “raw concrete.” In keeping with the modernist movement, which placed a strong emphasis on removing superfluous decoration, brutalism com- pletely eliminated ornamentation, eliciting strong public oppo- sition as it was considered an unsightly eyesore on the land- scape, according to Aotea ( www.aoteamade.co.nz/blogs/ journal/saving-concrete-a-look-at-brutalist-architecture ). Detractors often argue that the harsh, unvarnished appearance of brutalism is linked to a lack of insight and inventiveness, with brutalist buildings often portrayed as ugly blocks of university and college campuses that seem to be abandoned or in disuse, or depressing apartments with poor architectural design. But brutalist structures aren’t inherently disliked. According to Aotea , students adore the numerous brutalist or semi-brutal- ist residential buildings at the University of North Carolina, as well as the university’s two brutalist libraries—one brick and one concrete. Designed to boldly go against the grain and permanently alter cityscapes and skylines around the globe, the fundamental characteristics of brutalism architecture include unreserved use of raw concrete, geometric shapes, and an unwavering dedication to practicality, according to Indovance ( www. www.indovance.com/knowledge-center/brutalism-archi- tecture-a-bold-approach-to-building-design ), and while some may find its starkness inspiring, others consider it an acquired taste. However, the distinct charm of brutalist architecture is what made it so well-known in the 20 th century. Recognized for celebrating unapol- ogetically exposed structural features, its design helped cement its reputation as a movement that upholds the inherent beauty of unusual materials and unwavering functionality. Boston City Hall 17 CONSTRUCTION IN FOCUS Gaining popularity through the 1970s as a living example of how raw concrete can transform a space, brutalism is a very different architectural style from the elaborate ones that came before. Centred on embracing exposed concrete in its most unadulterated state, brutalist architects championed an unapologetic, raw beauty in urban construction, emerging as a reaction against earlier ornate and decorative architec- tural styles. French-Swiss architect Le Corbusier is credited with giving rise to the movement, says Architecture Courses ( www.architecturecourses.org/learn/distinctive-char- acteristics-brutalist-architecture ), with one of his greatest works of art, la Cité radieuse in Marseille, regarded by many as the first instance of brutalist architecture. Concrete’s natural strength and durability convinced Le Corbusier it was the best material for creating contemporary cities with build- ings that emit strength, simplicity, and order that naturally weather over time. Designed with purpose in mind, brutalism’s practicality puts function and utility first, and while they look imposing, the buildings frequently mesh well with their natural surroundings by incorporating landscaping and green areas that permit archi- tects to create a symbiotic relationship between structures and surroundings, making often harsh concrete landscapes more serene via integration with nature. While there are many examples of brutalist architecture around the world, one of the most famous is Montreal’s Habitat 67 designed by Moshe Safdie, which subverts precon- ceived ideas about what it means to live in an urban setting by assembling modular concrete units in an eye-catching, asymmetrical pattern. Every apartment has a private terrace, and the buildings’ connections foster a feeling of neighbour- hood among the concrete surroundings. Hugely famous and widely regarded as the shape of things to come according to Curbed when it made its debut at the Expo ‘67 World’s Fair, the apartment complex is made up of 354 prefabricated concrete modules that are stacked over a total of 12 stories in different configurations along with elevated walkways and rooftop gardens. Safdie intended for Habitat 67 apartments to provide seclusion and outdoor living areas in addition to promoting a feeling of community, and the design has influenced construc- tion projects around the world, according to Architecture Courses , including the Barbican Centre in London, which is home to a theatre, concert hall, art gallery, and residential buildings, and is proof of how versatile brutalist architecture can be in areas with multiple uses, with concrete towers and elevated walkways creating a distinctive urban ecosystem that combines living, culture, and nature. Habitat 67, Montréal The Barbican Centre, London DEC 2023 - JAN 2024 18Boston City Hall, created by the architects Kallmann, McKinnell, and Knowles, is considered a controversial example of American brutalism with its stark, angular façades and excessive concrete, representing the movement’s dedication to functionalism in public structures, while The National Theatre located on London’s South Bank is a well-known landmark on the Thames River, featuring exposed concrete surfaces, connected terraces, and dramatic fly towers. Since its founding in 1976, the National Theatre has served as a focal point for the performing arts in the United Kingdom. The Geisel Library in San Diego features striking concrete struc- ture and sharp angles, plus a library with an extensive Dr. Seuss collection. Cameron Offices in Canberra, Australia, designed by John Andrews and completed in 1972, is a prime example of the global reach of brutalism, despite having been partially demolished. Built on a six-acre site, this government complex features precast concrete and repeating geometric forms, pro- viding housing for about 4,000 public servants and demon- strating brutalism’s lasting impact outside of Europe. Even if you don’t personally care for brutalism, there’s no denying its influence on modern architecture, particularly its practicality, which continues to inspire many modern architects who incorporate its ideas into their creations. The movement’s emphasis on exposed materials, geometric purity, and function- alism has had a lasting impact on the architectural community. In fact, according to Architecture Courses , there’s a growing appreciation for the historical and architectural significance of brutalist buildings as they age. In order to maintain these buildings as an essential component of our urban fabric, preservation efforts are being carried out to safeguard and repair them. Because of their cultural significance, organi- zations and enthusiasts are putting forth endless effort to preserve brutalist landmarks for future generations as their audacious, unapologetic designs have irrevocably altered urban environments all over the world, upending precon- ceived ideas about what is beautiful and useful. The distinctive qualities and goals of brutalist architecture are still valued today, which inspires architects and urban planners to reconsider how to plan, develop, and design cities with a focus on geometry, concrete, and functionality. And while architectural styles will never be loved and appreciated by everyone, brutalism is a truly unique and immediately recog- nizable medium of artistic expression that inspires a strong reaction. Despite an evolution of construction from brutalism to more elegant buildings that exhibit architectural grandeur and are filled with sustainable features that reflect modern demands, brutalism’s utilization of nature and practicality are still useful today, particularly during ongoing housing crises and climate concerns. Despite being a relatively short-lived movement in architecture, brutalist supporters contend it’s an expression of unadulter- ated realism and an architectural power move. Whether you admire its distinct, potent, and raw aesthetic or scoff at its lack of pattern or colour and its ominous appearance of massive concrete blocks with blank façades, there’s no denying its long-lasting impact, with its unique aesthetics and unwavering approach to design that push society to appreciate the utilitar- ian as art, find elegance in the unpolished, and see beauty in the unusual. Designed by Isaac McWhinnie Boston City Hall Geisel Library, San DiegoThe Royal Theatre, LondonNext >