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Modular Structures: A Lesson from LEGO

With the recent advent of modular construction, a number of new and interesting projects are popping up all around the world.

Gluck+, an architectural firm based out of New York City, has designed a medium-income, seven storey, 28 unit apartment building in Upper Manhattan. The buildings lot size posed a serious concern for builders, as it does not provide the area required for traditional construction projects. Therefore, the architects at Gluck+ chose to assemble the residence using 56 pre-fabricated modules, all of which are built in a factory in Berwick, Pennsylvania (Architectural Record).

Proposed Modular Building in Upper Manhattan. Photo Credit: Gluck+

Building the modules in a factory allowed for high levels of quality control, and provided a much more comfortable building environment for workers. In addition, the project could proceed notwithstanding weather conditions. This has lead to an estimated 15% savings in total project cost. The construction time has also been drastically reduced, and the project will take just under one year to complete (four modular units are installed per day, after the initial foundation has been constructed). The residence, which is expected to be completed in October, is also quite aesthetically pleasing. By pulling some stacks forward and pushing others back, several terraces and overhangs are created, giving the structure a distinct look. The assembly process for the modules is presented in the following video:

A number of other modular residential buildings have been popping up in New York. A 32 storey residential housing unit in the Atlantic Yards development site is under construction. When completed, the building will be a whopping 322 ft tall and will hold the title of tallest modular building in New York. Skanska, the company building this project, has estimated that the total cost of the modular building will be 20% less than a traditional building (Skanska News Report). Similar to Gluck+’s design, 60% of the construction will occur off site. The modules will be built in a controlled environment in Brooklyn’s Navy Yard, and will be transported to site. As a result, the building is expected to attain LEED Silver certification, and produce 70 to 90% less construction waste (than traditional construction).

Final Render of the Tallest Modular Residential Building in New York. Photo Credit: Skanska

However, there are often risks when implementing new technologies. The Plumbing Foundation of New York City is suing the Department of Buildings for ignoring a number of major building safety rules. Stewart O’Brien, the executive director of the Plumbing Foundation stated, “It’s a dangerous path we walk down when the city appears to be willing to circumvent the clear words of the law so that wealthy and influential developers can make a few extra dollars by using lower paid and untrained assembly line workers” (The Real Deal).

Despite the issues that builders face with this new technology, it is apparent that modular buildings are becoming very popular with engineers and designers. Projects like this, as well as Sky City in China, are indicators of the shift in construction practices within the industry.

It seems quite ironic that the construction industry, which has a history of using immensely creative and complex building techniques, is now reverting quite successfully to the intuitive building style of LEGO.

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The Age of Disrepair: What Do We Do With All These Bridges?

The issue of ageing infrastructure has become a serious concern in countries throughout the world. Bridges built in the past century have begun to crumble causing serious  injuries, and in some cases death. In 2007, a bridge in Minnesota collapsed, killing 13 and injuring 145 people (I-35W Bridge Collapse) .Below is a video of the bridges collapse:

As a result, an investigation was conducted by the Federal Government of the United States to determine the cause of the collapse. In addition, the National Transit Safety Board was created to help improve the state of infrastructure and prevent future collapses. However, it seems that this issue has not been eradicated. During a speech in Galesburg, Illinois, President Obama stated, “We’ve got more than 100,000 bridges that are old enough to qualify for Medicare” (The Hill Report). According to a report released by Transportation for America, “11% of all bridges in the US are structurally deficient”. Considering that Americans make 260 million trips across bridges each day, this is a major issue (T4 America Report).

North of the border, Canadians are facing similar problems. A report released by Statistics Canada in 2007 stated that, “The average age of bridges went from 21.3 years in 1985 to 24.5 years in 2007, an increase of 3.2 years” (StatsCan Report). The province of Ontario has the third oldest bridge infrastructure in Canada (after Quebec and Nova Scotia) and its ailing bridge infrastructure has received a high degree of media attention. In Toronto, the capital of Ontario, the Gardiner Expressway has been identified as in need of serious repairs. The Gardiner is a major artery in Toronto’s downtown core, and a number of plans have been proposed to help rehabilitate it’s ageing bridges. However, the cost is quite steep. A current estimate puts the cost of repairing the bridge at $505 million (Globe and Mail Report).

Delamination on Gardiner Bridge Piers. Photo Credit: CBC News

It is well known that repairing older bridges drastically reduce maintenance costs. As a result, many engineers are starting to develop creative solutions to help restore these bridges. Innovation, unfortunately, comes with a price tag. As cities face more funding cuts, engineers are forced to use cheaper, less effective techniques to restore bridges. Professor Paul Gauvreau of the University of Toronto states, “When engineers are repeatedly requested to implement yesterday’s solutions – that is, not to innovate – engineering becomes a mere commodity that can be bought and sold at the lowest price” (Globe and Mail Report). As is often the case, these low-cost repairs are not very effective, and can lead to higher repair bills in the future.

A number of solutions have been proposed in the last few years that could potentially save cities millions of dollars on their repair bills. Some of these solutions include increasing the frequency of inspections, providing better drainage to current bridge decks, using domes to protect the bridge from rain and snow, and installing steel mesh beneath the bridges to catch any falling concrete (National Post Report).

Inspection of the Underside of a Bridge Deck in Missouri. Photo Credit: Missouri Department of Transportation

These solutions, however, are not always practical. More research needs to be done to find cost-effective repair techniques. Researchers all across the world are investing time and funding to help develop better, more efficient procedures for rehabilitating old bridges. As this research progresses, it will be interesting to see which solutions are adopted by the industry. In the meantime, cities will continue to pursue a ‘band-aid’ response to bridge deficiencies, leading to a higher potential for future accidents.

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The Future of High Rise Construction

In the new age of technology, the concept of “slow and steady wins the race” is becoming less and less applicable. In particular, China has recently constructed a series of buildings using pre-fabricated modular sections, cutting the time spent on the construction site to a matter of days.

The world was shocked when they first saw this phenomenon performed in Changasha China, where a thirty storey building was constructed in just fifteen days. If you have yet to see it, here is the amazing time-lapsed footage of the construction process:

The foundation for the structure was already installed prior to the thirty day count, reducing the overall “construction time”. In addition, the project used pre-fabricated modules that were constructed in a manufacturing plant and later shipped to the construction site. Once the pieces were on site, it was just a matter of putting the pieces in place (similar to a standard LEGO set).

The company behind all this, Broad Sustainable Building, is part of Broad Group which also works on a number of different products (i.e. Air Conditioning Equipment, Air Quality Technology, etc.). Their website has very minimal details, but claims that their buildings can withstand magnitude 9 earthquakes. They also allege that they are 5 times more energy efficient, have 20 times purer air, and use 6 times less material. To find out more about Broad Group, you can visit their website at the following link:

Broad Group Website

In addition to this, construction has begun on the soon-to-be tallest building in the world, the aptly named Sky City.

Sky City. Photo Credit: Web Odysseium

Sky City, which will cost less than 1 billion dollars US, will rise to a height of 838 meters (10 meters taller than the Burj Khalifa). The building is set to be completed in April 2014, less than a year before the start of construction. To put that into perspective, the Burj Khalifa took more than five years to build and had a total cost of 1.5 billion dollars US (see CNN Report).

It is quite amazing to think that the processes used in construction have been nearly stagnant for thousands of years. The Egyptians employed a similar style of on-site construction when they began building the pyramids. Over the years, construction times for the worlds largest structures have reduced from 20 years to just over 5. With the new prefabricated structures, construction times have been reduced to less than one year, a truly magnificent feat. This allows engineers to think both ‘bigger’ and ‘higher’ as the cost of constructing buildings using the new technique is greatly reduced.

The concept of prefabrication is not new, but employing it at such a scale is quite revolutionary. It takes the work typically performed on the construction site and moves it into the much more comfortable, controlled environment of the manufacturing plant. As this industry grows, there will be much debate as to which construction process provides the safest, well-rounded structures. Either way, the entire industry is in need of a much needed facelift, and this new process may be just the spark it’s been waiting for.

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Welcome to Structural Digest

They say everything in life is a learning process. I can say from experience, that a blog is no different. If you know me, you know that I love to read. I read everything from books to news articles. However, I have never really been too fond of blogs. The majority of structural engineering news that I am interested in comes from scientific journals and papers. Despite that, one must adapt to the changing times. I believe that in this day and age, a blog can be the perfect way to share ideas, interests, and spark discussions.

This blog combines my passion for news and information with my passion for sharing. Throughout the week I often run into stories of new structures around the world breaking ground (literally and figuratively), and this blog is the perfect platform to share them with you, the readers. The world is an amazing place: cities that used to house camel farmers now host the most powerful people in the world. One of my favourite images puts this into perspective:

The Old vs. New Dubai

The photo is able to capture the essence of Dubai. It illustrates the effect of the economic boom which has caused the region to become one of the hottest destinations (both literally and figuratively) in the world.

Both the purpose and goal of this blog is to present the most interesting images, videos and stories regarding the world of structural engineering. If you love structures, architecture, and everything in-between, then this is the perfect place to be.

Now, time to write the first real article….where to begin?