Thoughts on the Engineering Industry

A blog covering engineering, technology and business topics

Archive for the category “Sustainability”

Incorporating Engineering into Government to Improve National Programs

Hello everyone, I hope y’all have been doing well.  Today I would like discuss ways to improve our country by involving engineers and engineering concepts in the management of our national systems.  I have narrowed it down what I believe to be the 5 basic ideas.  As a reference, I have used data and assertions made by Evan Twarog in an article describing the role technocracy in China.

1) Become more technocratic in regards to politics

Data shows that the government is mostly run by engineers in China and in the government in the US is mostly run by lawyers.  In addition, Chinese people believe that knowledgeable elite should run the government which led to a technocracy being a part of the political system.  Based on the way government seems to operate in the US, I could see a shift towards the concept technocracy being beneficial for the U.S. as well.  Especially considering some of the issues that confront us, such the deterioration of the infrastructure, climate change, drought in various areas through out the country, and the production of energy in regards oil, wind, solar, etc.  A technocracy provides the critical knowledge and skill sets to properly deal with these issues.

2) Any problem can be solved with an engineering mindset

Engineers have a unique skill set that allows them to solve problems through a standard process.  On a personal level, I apply this mindset to difficult decisions in my life.  I bet you a lot of engineers say the same thing.  I don’t know about them but it works well for me.  And when considering the successes and failures of both China and the U.S., a correlation between the application of technology and the engineering mindset can be observed.  A good example of that in the U.S. is the space program and national arms race in general.  It is this correlation that leads to believe that the engineering problem solving mindset would be a good framework to apply to struggling government processes and programs.

3) An education in a technological field is more respected by society

For years, the culture in China has valued being technologically informed.  This means that changes in the direction of the country are more easily understood and communicated to the masses.  This is not to say there aren’t people capable of doing that here in the U.S., but there still seems to be a large portion of the political system that caters to the lowest common denominator instead of embracing the intelligence of the U.S. population.

4) Some projects need support from the government to succeed

A lot of the great engineering accomplishments require a large amount resources to back them up.  There are very few people and companies that can fully implement these systems.  This means that if there is some technology or engineering program that would improve our country and it is sufficiently large enough that it would be difficult for private organizations, government should not be afraid to step in and help.  If applied with an engineering problem solving mindset and backed by an informed public, these projects should benefit the country overall.

5) Export your technology for economic profit

This is where the practicality of investing money in solving these problems is realized.  In a perfect world, providing infrastructure and services to improve the lives of people is enough.  But government cannot be expected keeping doing so if it cannot be maintained as far as resources are concerned.  This means that sharing the technology nets the government money which can be used to further improve in other areas.  Business concepts like public-private partnerships were designed to improve profits and gains for the country through the development of these infrastructure and service ideas.  If we can keep this end goal in mind, it can ensure that all government systems improve the country socially and economically.

What is your opinion on these 5 concepts?  Is there anything you would add or take away and why?  If you enjoyed reading the blog post, be sure to like the post and share it with your friends.  Thanks for your time and have a good week!

Source

“The Three Gorges Dam, Why China is Run by Engineers”, Twarog, Evan, Atomic Insights, April 13, 2015, http://goo.gl/sZf3Zn

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3-D Printed Buildings Elements Created from Building Construction Waste

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     Hello everyone, I hope y’all have been doing well.  Today I would like to talk about an improved application of 3D in building construction.  For a while now, 3-D printing has been applied to building construction on a smaller scale.  However, the large portion of the structure has still been constructed using conventional methods.  Experts in various fields of building design and construction have been researching applications that expand the usage of 3-D printing in building construction.  This is an area of building construction expertise in which China has recently lead the global market according to Brittney Stevenson.

In April 2014, WinSun Decoration Design Engineering Co. revealed that 10 homes were constructed entirely out of a 3-D printed, recycled concrete material – an advancement that surprised the engineering and construction community.  In January 2015, it was revealed that WinSun had made further advancements in the applications of this 3-D printed material.  A 6-story apartment building and home has been constructed and the apartment building itself has an approximately 1,100 square meter floor plan.

The 3-D printed elements were created by inputing a CAD file into a 20′ tall, 33′ ft wide, and 132′ foot long machine printed using a concrete mixture.  The concrete mixture includes concrete, fiberglass, sand and a hardening agent.  The usage of this material allows for improved reusage of general construction waste while also being flexible, self-insulating and resistant to earthquakes.  Reinforcement was used where further strength was required and some of the larger pieces were built off site and transported there.  Details of the of building construction process are listed in the article.  According to WinSun, they are able to save 60% of the materials required for home construction, construct the building in 30% less time than traditional construction and reduce the required labor by 80%.

These are impressive results if true.  I still wonder about the expense of owning and maintaining the machine might be a hindrance at first. And I would hope the cost of collecting the construction waste and creating the concrete mixture is included in those statistics.  I think this is a good innovation, especially for low rise buildings since the loads and stresses are lower (although I believe a 6 story building is pushing the limits of standard low rise construction).  I would be interested to see how the material ages in regards to long term durability as well.  Overall, there are several applications that this would be useful for in the building construction industry.

What your thoughts on 3-D printed building elements? What about the concrete mixture used?  Have you heard of any other building materials being used in relation to 3-D printing?  If you enjoyed the article, please like it and share it with your friends.  Thanks for reading and have a good week!

Source

Brittney Stevenson, “Shanghai-Based WinSun 3D Prints 6-Story Apartment Building and an Incredible Home”, 3D Printer & 3D Printing News, January 18, 2015, http://goo.gl/TwVSKC

Tax incentives for promoting renewable energy production

Hello everyone, I hope your week is going well.  Today I would like to look at a topic that is less technical and a more political – how to implement tax incentives that promote sustainable energy production.  I believe that this is a topic that gets over-politicized and some information needs to be shared in an objective way.

Currently, there are a lot of subsidies provided to oil companies.  According to Oil Change International, the subsidies range from $10 to $52 million annually in the US.  Internationally, the subsidies are somewhere between $775 billion and $1 trillion.  As of July 2014, Oil Change International estimates this years subsidies to be about $35 billion.  $2.4 billion of those subsidies go to the big 5 oil companies in the form of federal tax deductions: BP, Exxon, Chevron, Shell, and ConocoPhillips.  Subsidies also go to “independent” oil companies which, which are larger operations than the name implies.  These companies produce about 50% of the oil.  The rest of the subsidies are earned through loans or aid certain types of operations such gas exploration and production at an estimate value of $18.5 billion on the federal level and $21.6 billion on the state level.  After that, there are consumption subsidies which amount to $11 billion.  Along with the subsidies, infrastructure loans are provided to the companies which amount to about $4.7 billion.  It shouldn’t be noted that the article goes on to recommend that these subsidies be reduced and also outlines roadway maintenance and health concerns.  That being said, I am trying to keep the references focused on the raw data in this section.

In comparison, the subsidies for renewable energy are lower.  A report by Nancy Pfund and Ben Healey shows that the renewable energy has a lower initial investment and projected investment over a 30 year span overall.  The historical average of annual subsidies of renewable energy is $370 million as compared to $4.86 billion for oil and gas, $3.5 billion of nuclear and $1.08 billion for biofuel.  Interestingly enough, nuclear had far greater initial investment than the other forms of energy; however, safety concerns caused there to be a large reduction those investments.

My current opinion is that we need to strip away a lot of the “blank check” type subsidies.  While there are probably subsidies for every industry that could fit in this category, the worst offender in this regard is the oil and gas industry.  I also think that some practicality is warranted too.  In my opinion, oil and gas will still always be the best option for hauling goods across the country for the next couple of decades.  Renewables can’t provide the efficiency needed and other tech such as nuclear is not scaleable enough for that yet.  For electric power production, I believe renewables can’t completely fill that gap either and stable energy production is needed for peak hours.  With all that being said, a balanced merit system needs to be applied to energy subsidies to produce the most sustainable energy infrastructure possible.

What is your opinion on how to best subsidize energy industry?  What is your opinion on the current state of subsidies?  If you enjoyed reading this post, like this post and share it.  Thanks for reading have a good day.

Sources

“Fossil Fuel Subsidies”, Oil Change International, 2014, http://goo.gl/BYdMg

Nancy Pfund and Ben Healey, “What Would Jefferson Do?: The Historical Role of Federal Subsidies in Shaping America’s Energy Future”, September 2011, http://goo.gl/XuioTH

Image Source

Roger H. Bezdek and Robert M. Wendling, “Energy Subsidy Myths and Realities”, June 2012, http://goo.gl/A8Ws96

Application of 3-D Printing and Modular Design to Construction

Hello everyone, I hope you guys had a good weekend.  Today I would like to discuss a couple innovations which apply 3-D printing and modular design innovations to construction practice.  These are applications that were more common in manufacturing and prototyping initially but can be applied to construction as well according to the article by Business Review Weekly.

The first innovation is the application of 3-D printing to the creation of moulds for precast concrete.  Traditionally, other materials such as wood, foam or rubber have been use, and constructing these moulds could take months to construct.  The Laing O’Rourke Company has developed a method that 3-D prints a large scale wax substrate mould at a rate of 150 kg/hr using a robots.  They have applied this to common projects such as stormwater pipes and have achieved cost savings of 50% to 90%.  Additionally, this solves the waste problem because the wax mould is lifted off or melted away in a water bath after the concrete is cured.  The wax can then be filtered and recycled.

The second innovation is the use of modular components in hospital construction.  Hospitals are one of the most expensive areas of infrastructure because they are individually designed.  Hickory Group has developed a modular panel for use in reception and administrative areas.  These areas use what is referred to as “accommodation components” which constitutes up to 40% of the construction cost of a hospital.  By using the modular panel, construction time can be cut by 40%.  Furthermore, the panels are easily replaceable.  If a panel is damaged, the hospital  can simply order a replacement and have their maintenance worker install the new panel.

Both of these are very good innovations in my opinion.  They are taking methods that have been proven effective in several previously tested applications and expanded their usage.  Furthermore, a reduction in time of construction and cost of maintenance/construction has been achieved.  I would be interested in seeing a more detailed account of the numbers and statistics.   However, based on the information provided, these are great examples of low risk/high reward solutions that can greatly improve construction practices.

What is your opinion on these innovations?  Do you think they’ll be effective?  If you enjoyed reading, like the post and share it with your friends.  Thanks for your time and have a good week!

Sources

Michael Bleby, “BRW Most Innovative Companies 2014: Why Construction Companies Are Thinking Like Manufacturers”, Business Review Weekly, October 9, 2014, http://goo.gl/O0oD6E

Image Source

Anne-Mette Manelius, “Concrete After Dark – Is There An Afterlife for Concrete?”, Concretely, October 17, 2014, http://goo.gl/IYI6q2

Benefits and Implementation of “Green” Urban Design

Hello everyone! I hope everything is going well.  This week I would like to talk about the incorporating “green” elements to city planning. I read an article a while ago that pointed out some interesting aspects of city life.  Most people who live in cities don’t notice nature around them in cities, instead they go on vacation to find nature.  Furthermore, more and more of the world’s population lives in cities.

This article listed the following benefits of the inclusion of nature into a city:

  • improved health and lifestyle
  • increased lifespan
  • reduced stress and aggression

Traditionally, the use of green space has been an aesthetic concern rather than a requirement for psychological health.  In addition to that, most urban planners haven’t claimed ownership of the issues related to lack greenery in the cities.  However, that is changing in Detroit, Europe and Singapore.  The researchers believe that greenery needs to be incorporated into urban planning from the ground up.

The article recommends that urban planners start incorporating the following elements to urban planning:

  • to consider the value of the greenery in an area before starting construction
  • to cluster homes and leave some easily accessible locations with greenery or natural elements around neighborhoods for city dwellers
  • to quantify the costs/benefits of different types of greenery and invest in them accordingly

While I think that some of the contributors come across as overzealous at moments, I agree with the concept.  Some of my most relaxing moments when I lived in Arlington, TX were the times I spent running at River Legacy Park.  It was a park that had a great section of in which I could loose myself in nature and reach a zen-type running state.  This article highlights benefits of incorporating nature that I have experienced myself.

What are your thoughts on incorporating nature into cities?  Do you agree with the articles assessment?  What would you do to incorporate nature into cities?  If you enjoyed the post, like it and share it with your friends.  Thank you for your time and have a good week!

Source

Anderson, Erin, “How Green Cities are Better for us Physically and Psychologically”, The Globe and Mail, July 5, 2014, http://goo.gl/PgM8Da

3 New Applications for Bamboo in Building Structures

Hello everyone! I hope everything is going well. Today I would like to talk about some potential uses for bamboo that are being incorporated into building structures.  Bamboo is most commonly used as a structural element in middle and lower income housing in China or Latin America.  It’s usage has started to expand to the eco-tourism structures as well, but is still mostly used for it’s aesthetic appeal in main stream structures.
 
Bamboo has previously not been considered useful in structural building design in comparison to other materials.  However, there are some properties that could be useful.  Bamboo is flexible, shock resistant, and more readily available in certain areas of world.  Below is a list of three applications involving bamboo that could be useful for building design in my opinion.
 
1. Wood Framing Material
The flexibility and shock resistant nature of bamboo could make it a very useful wood framing material.  There are certainly stronger and stiffer wood framing materials available on the whole.  However, depending on the accessibility and the requirements of the structure, bamboo could meet the load capacity demands.  Furthermore, methods such as the ones listed below could be applied as well.
 
2. Linking to Create a Wall
The bamboo can be linked together to create a wall.  It can be curved or straight and be equally easy to construct/build in both methods.  The solidity of the wall can be changed as well.  The article source mentions a process where the bamboo is cut in half, hooked to the next section, and then linked together.  There are plenty of creative options for creating a wall that follows this basic principal that would replace a traditional wood sheathing wall.
 
3. Concrete Reinforcement
The bamboo can be filled with concrete to increase the overall stiffness and crushing strength of the bamboo system.  The way that best describes the benefits is modern masonry – the only difference is the location of the different elements.  For masonry, the exterior part provides the stiffness and crushing resistance while the interior reinforcement provides the flexibility and tension strength.  It would be the opposite in the case of bamboo.  Using this method, the load bearing capacity of a bamboo wall, floor, or framing system could be greatly increased.
 
What is your opinion on the use of bamboo in building structures?  What is your opinion on the applications mentioned above?  Are there any other applications you can see being beneficial?  If you enjoyed the post, like it and share it with your friends.  Thank you for your time and have a good week!
 
Source
 
Ahlblad, Hannah, “Merging Bamboo and Concrete for the Emerging World”, ArchDaily, August 13, 2014, http://goo.gl/ROolCU 

Growth of the “Forgotten” Renewable Energy

Hello, I hope everyone is doing well.  Today, I would like to discuss a recent growth in geothermal energy.  Geothermal energy uses the power of water heated to steam temperatures to spin turbines that produce electricity.  Geothermal energy is sometimes described as the “forgotten” renewable because it is by far the least popular and well known renewable energy compared to wind and solar.  Furthermore, geothermal energy only produces 1% percent of electrical power worldwide according to the World Energy Outlook.  However, geothermal energy is growing as drilling for oil  and natural gas increases.  The Geothermal Energy Association reports that geothermal resources grew by about 4% to 5% recently.

Interest in the geothermal industry is growing internationally as well as domestically and international development banks are helping to finance these projects.  According to Maria Richards at SMU, “If you’re  wildcatting for geothermal, Africa is really of those parts of the world where we seem to be going…”  Large projects are also planned for Indonesia and some Central/South American countries as well as East Africa.  In addition, the Ring of Fire is a current hot spot for new production because it has high temperatures relatively close to the earth’s surfaces.

There are several benefits to the use of geothermal energy.  Compared to other electric power production methods, geothermal energy can heat and cool homes at lower temperatures.  This source can also be used to produce energy consistently 24 hours day, unlike the other renewables which are intermittent in nature.  This could also be a good alternative source of energy for countries, like Kenya and El Salvador, that rely heavily on hydroelectric energy.

However, there are disadvantages to geothermal energy as well.  Research has found that 50% to 60% of a typical geothermal drilling project is up front with a 10% to 30% chance that the drilling will be unsuccessful.  Richards sums it up best with this observation: “You can put out a meter and measure easily how much wind and solar is at a site.  You can get real data.”  But it is “much harder to understand” how much geothermal hot water is available in a certain area.

The recent developments of oil and gas have allowed for increased research in this field though.  The drilling has allowed researchers to improve data on temperature, water availability and seismic data.  Furthermore, the researchers at SMU hope to incorporate previously drilled oil and gas wells, like the Huabei oil field near Beijing, to produce small scale geothermal power.  Countries that are trying to reduce their reliance on traditional fuels are the ones pursuing this research most actively.  China is trying to increase their geothermal production to reduce their smog and ease reliance on traditional fuels for their growing population.  Munich, Germany is hoping to obtain all its heating from renewables by 2025 and plans on most of it being geothermal. It is also predicted that many more places around the Ring of Fire will develop geothermal energy faster than other locations as research continues.

I am interested to see how this industry grows with the development of this research.  It is my opinion that this energy has the potential to fill the gap that other renewables have in regards to consistent energy production.  Furthermore, the knowledge gained from oil and gas drilling, as well as the previously drilled wells, could greatly reduce the up front costs.  What is your opinion on this renewable resource? What are your predictions for the future of this industry?  Be sure to follow me and share this article if you enjoyed it.  Thanks for your time and have a good week!

Reference:

Galbraith, Kate, “Geothermal Industry Grows, With Help From Oil and Gas Drilling”, New York Times Online, July 23, 2014, http://goo.gl/ixL318 

Benefits of Reusing Composite Shingles in Asphalt Roadway Construction

Hello everyone! I hope y’all have been doing well.  Today, I want to talk about an interesting innovation I read about the construction of O’Hare Airport. (http://goo.gl/WjI8Ek)  They collected used composite asphalt shingles and used them as part of the asphalt binder in the runway and various road type structures for the facility.  In this post, I will outline the process and the benefits.

 
The process:
Old Shingles Are Collected:
First, shingles are collected for reuse in the system.  At first, there weren’t any incentives added to motivate people to recycle used shingles.  However, some incentives have been created through different programs in various locations – all them outlined in the article.  One of them is a ban on sending large amounts of shingles to the landfill.  Another concept is an increased charge for disposing of shingles as compared to providing them for reuse.  The only exception is shingles that incorporate asbestos in their production and various limitations are discussed for reducing that risk.  Overall, the incentives seemed effective in my opinion.
 
Shingles are mixed into a pure asphalt binder:
The next step is that shingles are ground up and melted.  Once melted, this product can be added to the pure asphalt binder to increase the volume of this asphalt binder product.  At O’Hare airport, the shingles made up a 3% percent portion.  This didn’t make a huge dent in the budget but depending on the project it could reduce costs more.  Statistics and comparisons are provided in the article.
 
Asphalt is Laid Like Normal:
The asphalt binder and resulting asphalt is used like before.  As long as any differences in material properties are accounted for, the design and construction remains the same.  This results in an easy implementation on the construction and design side of the process.
 
The Benefits:
Reduced Use of Oil:
Oil is a precious commodity; anytime it’s usage is reduced, I consider it a good thing.  Along with that, it is easier to get a hold of used shingles than oil.  For both of these reasons, I consider the reduced oil usage a considerable benefit.
 
Reduced Cost:
The cost of using reused shingles is lower than using a pure asphalt binder.  Unless the scale is large, it is a minimal cost difference.  However, considering the scale of infrastructure cost these days and the amount of repairs needed, the scale is large enough that it would make a difference.
 
Reduced Waste:
These shingles, if not used in this capacity, would most likely be going to a landfill.  The lack of landfill space and shear quantity of human waste going to landfills is a current issue and reducing the amount from the housing would be a large contribution towards reducing that waste.
 
What is your opinion on the usage of this mixed asphalt binder?  Does it provide enough benefits to outweigh the cost and effort of changing the process?  Are there any noteworthy drawbacks or additional benefits not mentioned?  Thanks for your time and have a good week!
 
Sources:
Jon Hilkevitch, “Getting Around: Old Shingles Get New Life on O’Hare Runway”, Chicago Tribune News, June 30, 2014, http://goo.gl/WjI8Ek
 
Image Source:
“Why Homeowners Should Choose Asphalt Roofing Shingles Recycling”, Asphalt Roofing Shingles Recycling, October 18, 2012, http://goo.gl/u9l7cD

Concrete Eating Robots: A More Efficient Method of Breaking Down Concrete?

 

     Hello everyone.  I hope everything is going well.  I had a good Easter weekend with my family and I’m feeling rested after a busy week.  Today, I would like to talk about an innovation I read about a few weeks ago which is called a “Concrete Eating Robot” as described in a blog post by Peloton Land Solutions.

     The Concrete Eating Robot is a system which uses a high pressure water jet to break down concrete rather than using a wrecking ball or something else to crush concrete.  The water/concrete slurry is then collected to reclaim the reusable materials.  The clean aggregate can be used in other concrete mixes.  The water is reused by the system so that a large of amount of water isn’t wasted in the process.  And the clean and reusable rebar beneath the concrete can be pulled apart for use in other structures.  The only waste that I could find according to the article by Peloton Land Solutions is the cement mixture that can’t be reused.

     This invention has some very good benefits in that the rebar and aggregate can be reused in a very efficient manner.  However, cement is the least sustainable product required for concrete construction.  And in this case, I didn’t see a method for recycling cement which could make this a critical issue.  Depending on the situation, this could negate some of the benefits to the point that this invention might not be worth the investment.  For example, if this is a case where a high amount of cement is required and aggregate can be easily procured locally for any new construction, the cost benefit ratio might tilt back towards a more traditional method.  If this is a low to zero cement usage concrete in an area where the required aggregate isn’t easily obtainable, this would be a better situation for something like this.

   Here is a more detailed article on the device: http://goo.gl/SWDwN2

   What is your opinion on this invention? Do you see it being used regularly in the future?  Thanks for your time and have a good week!

Resources:

Peloton Land Solutions, “Concrete Eating Robots?”, March 3rd, 2014, http://goo.gl/Y920hK

CoExist Blog, “This Concrete Eating Robot Can Recycle an Entire Building on the Spot”, April 16th, 2014, http://goo.gl/SWDwN2

The Application of Biologically Grown Materials to Building Design

Hello everyone, I hope y’all had good weekend.  Today, I want to talk about some new building materials being researched that are biological produced in a replicable process.  One of the common characteristics is that these materials will involve bacteria or something else derived from organisms.  The fact that these materials don’t require significant carbon output is one major benefit.  Another benefit for most of these materials is that they are actively reproduced over time once they are installed as well.  The building materials are described below with some insight on possible benefits and issues.

bioMason Brickshttp://goo.gl/PY68HQ

The bioMason brick is a brick of sand and cementitious material in which the cementitious material is created using a bacteria.  The brick mixture is created and over the course of 5 days the bacteria solidifies into a coral type material with the strength of a normal brick.  The major benefit for this innovation is that it doesn’t require the heat and raw materials used in creating normal bricks; this reduces the cost of the brick by 40%.  They are currently conducting experiments to research bacteria creation using the following materials: urea, salt and yeast extracts, and seawater.

I see this having one major benefit – it would not significantly change the design and build process for masonry.  Masonry strength is mostly determined by the strength of the mortar as long as the masonry unit strength doesn’t change significantly.  The benefits of the bioMason bricks combined with the low technology change requirement makes this much more effective.

Mushroom Insulation Materialhttp://goo.gl/SZcfA

This is a stiff insulation material using plant stalks and husks combined with Mycelium.  There are two forms of application being tested currently: growth inside the wall and spray on insulation.  The insulation is fire resistant and fully compostable.  Additionally, it does not contain formaldehyde or any other harmful organic materials.  This same material can also be used as compostable packaging material.

There are several benefits to this material.  Like before there is no significant change to the other building processes related to it.  It also has great applications outside of this usage alone and is completely compostable once it is not needed anymore.  The only drawback I can potentially see is there being an organic material harmful to humans that is unknown as of yet – similar to what happened with Asbestos. It has great potential overall though – it is my recommendation that more health testing be done before large scale usage.

Self Repairing Concrete:

Research is being conducted on a bacteria that can be used to repair concrete as it ages.  Bacteria engineered to thrive in dry climates is being created to be placed in the concrete mixture.  The bacteria would release Calcium Carbonate as part of the waste process which would fill the holes and cracks over time.

There is one possible major benefit I see – the reduction in maintenance required for the concrete designed this way.  However, more research would be required to determine it’s efficiency.  Additionally, nothing is mentioned about resources and energy required to produce this bacteria; if it requires a high amount of energy and time/raw material resources, it may become impractical to use.  I might also add that the issue of infection might come up here as well; but if the claim is true that it is bacteria that thrives in dry climates, the danger to living organisms would be greatly reduced.

What is your opinion on these possible advancements?  Can you see them being used in the future?  Thank you for your time and have a good week!

Reference:

Wollenhaupt, Gary,”Self-Repairing Concrete Could be the Future of Green Building”, Forbes Online, January 6, 2014, http://goo.gl/IRyzHi

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