Future cities could be 3D printed

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Future cities could be 3D printed – using concrete made with recycled glass

By Seyed Ghaffar, Brunel University London; Mehdi Chougan, Brunel University London, and Pawel Sikora

The featured image above is credit to Matjazz/Shutterstock

3D printed concrete may lead to a shift in architecture and construction. Because it can be used to produce new shapes and forms that current technologies struggle with, it may change the centuries-old processes and procedures that are still used to construct buildings, resulting in lower costs and saved time.

However, concrete has a significant environmental impact. Vast quantities of natural sand are currently used to meet the world’s insatiable appetite for concrete, at great cost to the environment. In general, the construction industry struggles with sustainability. It creates around 35% of all landfill waste globally.

Our new research suggests a way to curb this impact. We have trialled using recycled glass as a component of concrete for 3D printing.

Concrete is made of a mix of cement, water, and aggregates such as sand. We trialled replacing up to 100% of the aggregate in the mix with glass. Simply put, glass is produced from sand, is easy to recycle, and can be used to make concrete without any complex processing.

Demand from the construction industry could also help ensure glass is recycled. In 2018 in the US only a quarter of glass was recycled, with more than half going to landfill.

Building better

We used brown soda-lime beverage glass obtained from a local recycling company. The glass bottles were first crushed using a crushing machine and then the crushed pieces were washed, dried, milled, and sieved. The resulting particles were smaller than a millimetre square.

The crushed glass was then used to make concrete in the same way that sand would be. We used this concrete to 3D print wall elements and prefabricated building blocks that could be fitted together to make a whole building.

A building envelope prefabricated using the 3D printing process. Mehdi Chougan, Author provided

If used in this way, waste glass can find a new life as part of a construction material.

The presence of glass does not only solve the problem of waste but also contributes to the development of a concrete with superior properties than that containing natural sand.

The thermal conductivity of soda-lime glass – the most common type of glass, which you find in windows and bottles – is more than three times lower than that of quartz aggregate, which is used extensively in concrete. This means that concrete containing recycled glass has better insulation properties. They could substantially decrease the costs required for cooling or heating during summer or winter.

Improving sustainability

We also made other changes to the concrete mixture in order to make it more sustainable as a building material, including replacing some of the Portland cement with limestone powder.

Portland cement is a key component of concrete, used to bind the other ingredients together into a mix that will harden. However, the production of ordinary Portland cement leads to the release of significant amounts of carbon dioxide as well as other greenhouse gases. The cement production industry accounts for around 8% of all carbon dioxide emissions in the environment.

Limestone is less hazardous and has less environmental impact during the its production process than Portland cement. It can be used instead of ordinary Portland cement in concrete for 3D printing without a reduction in the quality of the printing mixture.

3D printed layers of a wall element. Mehdi Chougan, Author provided

We also added lightweight fillers, made from tiny hollow thermoplastic spheres, to reduce the density of the concrete. This changed the thermal conductivity of the concrete, reducing it by up to 40% when compared with other concrete used for 3D printing. This further improved the insulation properties of the concrete, and reduced the amount of raw material required.

Using 3D printing technology, we can simply develop a wall structure on a computer, convert it to simple code and send it to a 3D printer to be constructed. 3D printers can operate for 24 hours a day, decrease the amount of waste produced, as well as increase the safety of construction workers.

Our research shows that an ultra-lightweight, well insulated 3D building is possible – something that could be a vital step on our mission towards net zero.

Seyed Ghaffar, Associate Professor in Civil Engineering and Environmental Materials, Brunel University London; Mehdi Chougan, Marie Skłodowska-Curie Research Fellow, Brunel University London, and Pawel Sikora, Associate professor in Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin

Read the original article.

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Dubai, Doha and Riyadh among top 5 in MENA ranking

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In the MENA region through the years, wealth has always been absent and this for millennia especially in the Gulf area. Nowadays, images of gold buildings, fantastic motorways, and all the most expensive things in life have become commonly known and used.
In the Gulf, however, one thing comes to most people’s minds first. It is oil. Dubai, Doha and Riyadh are among the top 5 in MENA ranking would not be a surprise since this region rich with its rich oil reserves and supply of that oil is one reason and a good one for those cities in this area have earned a spot on the list of the world’s wealthiest nations.
Now turning that wealth into smart cities could be considered to be some achievement.

The above image is for illustration and is of Doha, Qatar.

Dubai, Doha and Riyadh among top 5 in MENA ranking

Rudolph Lohmeyer and Antoine Nasr

Dubai continues to lead the region in Kearney’s Global Cities report climbing four places in the global ranking, while Doha experienced the most dramatic jump globally, placing it third regionally, while Riyadh ranks fifth in Mena.

Riyadh also leads in Human Capital dimension in the GCC, highlighting its ongoing efforts in attracting international talent and large foreign-born population, according to the 11th edition of the report, which offers key insights into how Covid-19 and the resulting pandemic containment measures have impacted the level of global engagement of 156 cities around the world.

Comprising of Global Cities Index (GCI) and Global Cities Outlook (GCO), the report measures how globally engaged cities are across five dimensions: business activity, human capital, information exchange, cultural experience, and political engagement as part of the GCI. GCO, which is a forward-looking evaluation based on 13 indicators, assesses how the same cities are creating conditions for their future status as global hubs.

Global Cities Index

Dubai retains its top spot in the Index for the region, and is also ranked fourth globally in Cultural Experience, reflecting the city’s relatively early reopening to international travellers, bolstered by strict testing requirements, a rapid rollout of vaccines and Bluetooth-enabled contact tracing.

Doha saw the largest jump of any city on this year’s Global Cities Index, rising 15 places following the restoration of diplomatic relations between Qatar and its neighbouring countries, highlighting the importance of fostering regional relationships in addition to global ones.

Cairo ranked fourth in the Mena region, followed by Riyadh. Saudi Arabia’s capital city leads in Human Capital in the GCC, where its strengths in attracting international talent and large foreign-born population contribute to the strong showing. This is in line with the country’s increased emphasis on strengthening citizens’ capabilities to compete globally, in support of the realization of several strategic objectives set out in the Saudi Vision 2030.

Overall, 21 cities in the Mena region rose six or more positions in the GCI ranking compared to last year. Istanbul climbed seven spots, with the city’s efforts to become a global travel hub proving their worth. Addis Ababa moved up eight places, propelled by Ethiopia’s development investments that have supported rapid economic growth.

Global Cities Outlook

In terms of outlook, Abu Dhabi ranks fourth globally, a testament to the city’s continued focus on providing accessible, high-quality healthcare and a commitment to reducing its environmental impact, which is core to the personal well-being dimension. Dubai and Abu Dhabi co-lead in the outlook for infrastructure, an illustration of the UAE’s commitment to a future of sustainable and resilient economic growth.

Antoine Nasr, Partner, Government Practice Leader, Kearney Middle East, said: “In Mena, GCC economies, particularly the UAE and Saudi Arabia, are poised to lead regional recovery supported by accelerated efforts of their governments across the five main dimensions of the report. What’s also noteworthy is Doha has recorded the biggest gain globally for any city, a result of the compounded benefits of their strengthened economy and the newly restored regional ties. This reflects the importance of a balance between self-sufficiency and global connectivity.”

Five strategic imperatives for city leaders

The report highlights five strategic imperatives for city leaders along with a range of ways in which cities around the world can address the challenges they share:

•    Win in the competition for global talent: with human capital as the driving force behind economic activity, cities that adapt to the new priorities of prospective residents, with a renewed emphasis on urban livability and economic opportunity, will be those that emerge on top
•    Embrace the rapidly growing digital economy: while it threatens to contribute to an emptying of cities and relocation of business headquarters, cities that harness the benefits of the global digital economy to drive differentiated competitive advantage will accelerate economic growth
•    Ensure economic resilience by balancing global and local resources: with the fragility of the global trade system exposed during the early months of the pandemic, cities that recalibrate and balance relationships at global, regional, and local levels will be most resilient to future disruptions
•    Adapt in the face of climate change: as climate change accelerates, and in the absence of unified global leadership on the topic, cities must lead the way in driving toward sustainability around the world
•    Invest in individual and community well-being: in recovering from the collective scars of the pandemic, cities that focus their investments on advancing the well-being of their populations will be those that create an environment in which innovation can thrive

“Though they were initially hit hardest by Covid-19, our 2021 report shows that the leading global cities have once again proven their resilience and adaptive capacity. Their broad diversity of strengths positioned them for a quicker rebound that, with leadership focus and clarity of direction, can transition into leadership of a long-term, global recovery,” concluded Rudolph Lohmeyer, Partner, National Transformations Institute, Kearney Middle East.

– TradeArabia News Service

How to build sustainable cities

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Construction Kenya’s INSIGHTS advises as to how to build sustainable cities for the good of all. Still, in an era of rapid urbanisation, we witness increasing demand for additional housing, infrastructure, transport and green spaces. We can only agree on how all around the world thinkers can help tackle these challenges.

How to build sustainable cities

More than 66% of humanity projected to live in urban areas by 2050.

By Jane Mwangasha

In the next thirty years, more than two thirds of humanity is projected to live in urban areas with most of the urban population growth expected to happen in lower income nations.

With that in mind, there is an urgent need for planners to ensure that urban areas are inclusive, safe, sustainable and resilient enough to meet the anticipated population growth.

But what makes a city liveable? While there is no single magical bullet, cities can make themselves more habitable by adopting a range of social and technological measures.

Here are 10 ways to build more sustainable cities:

1. Clean energy

Although most cities can generate clean energy, their high level of power consumption means the metropolises are unlikely to be self-sufficient in terms of energy production. 

However, cities can lower their carbon footprints by, among other things, converting sunshine into electricity; using timber from local forests to produce low-carbon energy for heating and electricity generation; and using solar to heat buildings and water.

Converting waste into energy is also a great step towards improving a city. The Indonesian city of Sodong, for example, has implemented an air-filled waste disposal system that uses pipes to suck trash from homes into processing centres that automatically sort the material to recycle and turn it into renewable energy.

London Heathrow, one of the busiest airports in the world, uses “springy” tiles to harness the kinetic energy in foot traffic and convert it into electricity.

Such innovations can help cities to become more sustainable.

2. Efficient buildings

Buildings consume most of a city’s energy intake while emitting large quantities of carbon. Cities should encourage the design and construction of efficient buildings – which are often more cost-effective and functional compared to installation of costly devices for clean energy production.

Creating efficient buildings involves the insulation of walls, windows, and roofs, and operating energy-efficient lighting and heating systems.

Passive House in Darmstadt, Germany, is a great example of energy efficient building. The ultra-low energy house is so highly insulated that it requires no heating or cooling.

Singapore and New York have shown the world how small initiatives such as painting roofs white and planting trees can reduce city temperatures by up to 2°C – thereby cutting a city’s energy consumption.

In Scandinavian and eastern European countries, hot water for heating is distributed to buildings through insulated pipes underneath the streets. The water is heated using energy generated from extremely efficient power stations that generate both heat and electricity.

3. Efficient transportation

While vehicles, trains and aeroplanes facilitate the smooth running of a city, the transport systems can cause traffic congestion, poor air quality and gas emissions. 

To minimise the number of cars on the road, some cities have formulated ideas that can be adopted in other parts of the world.

The Scottish city of Edinburgh, for example, has developed one of the largest car-sharing clubs in the UK, which allows members to use cars only when they need to.

Singapore and London have designed high-quality bus and underground rail systems, as well as low-emission areas where only electric vehicles are permitted.

In Copenhagen, Denmark, cycle commuting is highly encouraged with cyclists given priority at traffic lights throughout the city.

4. Urban agriculture

The food we eat comes with a carbon footprint, which is worse if the produce travels hundreds of miles to reach us. It is therefore a great idea to encourage urban farming to ensure local sourcing of foodstuffs.

Urban farmers such as US-based Aero Farms are already embracing vertical farming solutions to produce food in cities. Vertical farming produces crops on stacked layers, often on skyscrapers, instead of on a single layer in either an open field or a greenhouse.

Advances in lighting and automation, as well as other factors such as reduced use of pesticides, enable vertical farmers to make higher profits than traditional farmers.

5. Sharing spaces

City residents around the world are reducing the carbon footprint of consumption through sharing of resources. It is increasingly common to find inhabitants engaging in carpooling, lodging rental and shared ownership of facilities such as gyms and lounges.

6. Design for social integration

Once considered the world’s most dangerous city, Colombian city of Medellin has transformed itself by focusing on architecture and design.

The city has adopted the use of shared spaces and improved public transport to blur economic boundaries and create a sense of connection among its residents.

7. Mobility on demand

Smartphone-assisted traffic management and car routing can reduce time and fuel wasted trying to navigate through congested cities.

Likewise, self-driving vehicles and carpooling can increase efficiency by maximising use of vehicles and reducing the need for space to park idle cars.

8. Nature-based solutions

Nature-based solutions to urban problems can help cities to tackle climate change while reducing disaster risks.

New York City’s greened rooftops and streets that can better manage storm water runoff and improve urban climate are a great example of natured-based solutions.

Another great example is China’s introduction of the concept of ‘sponge cities’, cities with open spaces that can soak up floodwater and prevent disaster in ecologically friendly ways.

9. Pocket parks

In densely populated cities such as San Francisco, local authorities have put in place small green spaces that help to increase green cover while providing recreation space to residents.

Most pocket parks re-use spaces that previously served other purposes — for example, rehabilitated street parking spaces or a public right-of-way that was earlier used for transportation.

10. Pervious concrete

Pervious concrete is a mixture of cement, coarse aggregate, water and admixture, with little or no fine aggregates. It is designed to allow water to penetrate the asphalt for absorption by the earth. This can help cities to tackle flash floods and worsening quality of water in river courses and so on.

Hailed as one of the most promising sustainable material today, pervious concrete has outstanding potential to counteract these adverse impacts while providing necessary structural integrity, thus supporting continued urbanization.

Taking sustainable living to heart . . .

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INQUIRER.net Brand Room holds that taking sustainable living to heart is all about not only ignoring any Insanity of Sustainability but facing the future reality with serious consideration of sustainable habitability as envisaged by a Philippines based SM Development Corporation (SMDC).

City life is often compared to an urban jungle where people merely exist in a given space, in a given time.

But what if space and time are rediscovered with fulfilment felt by the dwellers in a community that thrives in sustainability of living? What if time and space are elements that give birth to economic advancement, environmental preservation and community progress?

The one thousand and one “what-ifs” are a thousand and one realities SMDC offers to people who deserve a thousand and one more chances of a life of quality. Not only today but also in the years – many, many years – to come. 

“Making cities sustainable means creating career and business opportunities, safe and affordable housing, and building resilient societies and economies,” the United Nations has said. 

Because today and tomorrow are important to SMDC, its communities are designed and run based on three sustainability pillars: economic, environmental, and social. 

More than a roof over one’s head

Community building, for SMDC, is more than just providing a roof over one’s head. It is about creating a place that allows people to thrive, where all the living essentials are within striking distance – from one’s daily necessities to opportunities for commerce, for jobs and for livelihood. 

Building a nation of homeowners, as envisioned by Chairman Henry Sy Jr., means providing homes that are practical – efficient in size, generous in amenities, luxurious in services and facilities.

South 2 Residences in Las Piñas City is built on the concept of 15-minute cities, where economic opportunities, everyday essentials and public services are reachable in 15 minutes or less.

Sustainability, after all, is about sharing spaces and resources, so that they become inclusive and affordable, while providing enough space for others to thrive. For people to continue to thrive, they need to be close to where the economic opportunities are, in major CBDs whose property prices are constantly skyrocketing. An SMDC home, therefore, does not just take care of today’s dwellers; it is a place where homeowners can reap good financial rewards, as a legacy that can be passed on to their children and their children’s children.

It is this idea of shared spaces that opens SMDC communities to the everyday home seeker. To be able to live in a safe community with hotel-like lobbies, resort-style amenities, 24/7 security, located in a major CBD, was a luxury available only to the rich. Now everyone can have a piece of that luxury. And by everyone, it also means individuals who may be challenged to live in vertical spaces. SMDC homes are built with accessibility provisions for seniors, children and PWDs.

More than just a breathing space

City living spaces are often viewed as concrete jungles devoid of breathing spaces. Community building by way of SMDC means creating homes where residents and guests not only enjoy vast, open spaces with lots of greenery, but also with energy efficiency as part and parcel of every design. Units are built to bring in natural light and ventilation, LED fixtures are used and a waste management system is in place.

Sands Residences brings to Manila a premium-quality waterfront home in a complete community that provides a lot of breathing space and magnificent views

Every development is built with disaster-resiliency and future-readiness in mind – from site selection to construction and beyond. SMDC’s property management personnel are trained to respond quickly to emergencies of all kinds. These trainings are made available to residents through regular workshops.

Being situated where all of life’s daily essentials are within walkable distances, not only encourages residents to walk, jog or bike, but also allows them to become stewards of the Earth by reducing their carbon footprint. SMDC’s sprawling amenities and activity areas encourage residents to spend more time outdoors, savor Nature and reduce energy consumption.

More than just existing

Sustainability is built around the concept of continued existence for people. But to continue to exist, i.e., to extend today’s lives and to continue life for the future, means being in a place where health and happiness are given primary importance. SMDC’s properties allow residents to take care of their physical, mental and emotional health through spaces designed for these activities, spaces that encourage the creation of social connections, the very concept of community building.

The Good Guys Weekend Market provides a venue for residents to continue generating income during this pandemic.

But mere spaces are not enough. There has to be a catalyst to make these connections, and community spirit, come to life. SMDC’s The Good Guys program, enables SMDC communities to come together in the spirit of conviviality, to provide for both economic and social progress for residents, and to extend this altruism beyond its communities.

Building happy, healthy, secure and thriving communities is the heart of sustainable living, as exemplified in SMDC HappyNings, 2-time Quill awardee for community relations.

There is no life in mere existing. To live is to exist sustainably.

In a given space and a given time, SMDC creates the space for people to live today and to continue to survive the challenges of time.

Read more Business stories:

Read more: https://business.inquirer.net/320617/smdc-taking-sustainable-living-to-heart#ixzz6r9DKzdl9

Dubai economy to contract by 11% this year

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Dubai economy to contract by 11% this year: S&P as the international lockdown impacted international travel to and stay in the previously popular spots of the world. Dubai, for its particular regional specifics and as the most popular venue in the Gulf region, seems to endure the most critically the pandemic or all the safeguards against it.


Dubai’s economy will contract by around 11% in 2020, owing mainly to the Covid-19 impact on its travel and tourism industry, the sector most affected by the pandemic, according to an S&P Global Ratings report. 

As per S&P estimate, Dubai’s gross general government debt will reach about 77% of GDP in 2020.

Low oil prices have had broad effects on GCC economies, of which Dubai is one, but hydrocarbons directly contribute only about 1% to Dubai’s total GDP. 

The indirect effect of weaker demand from Dubai’s neighbours will dampen Dubai’s trade, tourism, and real estate markets, it stated.

Although Dubai’s economy is somewhat more diversified than that of most its regional peers, the report anticipates an economic contraction of around 11% of GDP in 2020, recovering to 2019 levels by 2023. 

STR Global, a data intelligence and benchmarking firm, reported Dubai’s hotel occupancy rate at 26% in June as inbound tourism sharply declined following global lockdowns and much-reduced air travel designed to curb the spread of Covid-19. 

The fact that fewer residents left Dubai during the hot summer months and instead spent more domestically to some extent has supported the economy. Local support for the economy cannot, however, offset the almost complete shutdown of inbound international tourism for most of 2020, and the likely slow recovery of the long-haul aviation that Dubai specializes in.

The Dubai government now expects to post a deficit of AED12 billion (3.2% of GDP) this year, largely owing to the reduction in economic activity and the consequent expected 28% decline in revenue, stated S&P Global Ratings. 

It also expects significant off-balance-sheet expenditure, resulting in the government’s net debt position worsening by more than what the headline deficit would imply, as has occurred in previous years.

S&P Global Ratings pointed out that the below-the-line expenditure which causes the variance between headline deficits and the change in net debt mostly involves support for Dubai’s government-related entities (GREs), an example of which is the recently disclosed AED7.3 billion (1.9% of GDP) already provided to national carrier Emirates in 2020. 

Support for GREs will likely be appreciably larger in 2020 than in the past, due to the broad cross-sector shock to Dubai’s economy, it added.

The ratings major said that in total, it expected new government bond issuance and loans to total around 7% of GDP in 2020. The government has issued AED8.4 billion (2.2% of GDP) of public debt so far in 2020, marking the biggest year for Dubai’s debt issuance since 2009. 

“This, in combination with recently disclosed new bilateral and syndicated facilities through June 2020 (facilities that have increased by AED15 billion (4% of GDP) since Dubai’s previous end-2018 disclosures) supports our estimation that 2020 will be another year where debt accumulation far exceeds the headline deficit,” it stated in the review.

TradeArabia News Service