Page 24 - Built Expressions - Online Construction Magazine - November 2014 Issue

Tech - Bytes Could Scrap Rubber help Michigan build better Roads? group of researchers at Michigan Technological University is conducting tests which is a burden to our society and the A to fnd out if traditional asphalt mixed with rubber from scrap tires could environment as a sustainable material make better roads in Michigan. for infrastructure but we want to make The research, led by civil and environmental engineering department chair sure that we do not violate the standard David Hand, has been granted $1.2 million from the Michigan Department of of emissions by adding crumb rubber,” Environmental Quality. Professor Zhanping You has been studying the technology says Ahmed. of rubberized asphalt for eight years. He says rubber-added asphalt can make The research team is currently roads more durable and make life easier for drivers. conducting lab experiments and will “When we use rubber in asphalt, it’ll help us reduce cracking. So when you then move on to the feld testing phase drive on the road, it’s going to be quieter. Also, the rutting resistance is good. at a couple of sites in both Upper That’s ideal for pavements,” says You. Peninsula and downstate. BE To mix rubberized asphalt, You says some percentage of crumb rubber from waste tires will be added to traditional asphalt. The process will generate some initial cost, but it’s expected to be cost-effective for taxpayers in the long run. “Research reported that crumb rubberized asphalt can reduce the overall life cycle cost by about 15%,” says You.Assistant professor Zeyad Ahmed is also on the research team. He says another focus of the research is to test the emissions of the mixed elements. See more at: http://michiganradio.org/post/could- “Used tires are big problems for everybody. Our main goal is to use the material scrap-rubber-help-michigan-build-better-roads Development of Self-Healing Concrete Moves Close io-mineralisation is the process by which living “This method will help produce a new class of high Borganisms can produce minerals. and a possible method performance oriented fabric cement material, which to help promote masonry crack remediation. Scientists may open the way for a multitude of new products and at the Structural Engineering Research Centre (SERC) in applications. It is water as well as fre proof,” said Iyer. Chennai now believe they are getting closer to developing a The Delft University of Technology in the Netherlands ‘self-healing’ concrete for commercial use. has also been working on the incorporation of bacteria into “There are only a few ongoing research projects concrete. The bacteria produce calcium carbonate – akin to happening across the world on the use of micro-organisms mineral limestone, as a waste product, which can naturally in developing self-healing construction materials. SERC is fll in the cracks or holes. working with cell biologists to develop this concrete,” said Elsewhere, green building start-up bioMason has SERC director Nagesh R Iyer. developed a method for “growing” bricks via the use of The bacteria would be able to produce the minerals that bacterial colonies, thus dispensing with the need for energy- would help repair and cover building cracks. Not only does intensive manufacturing processes. The biomass bricks also this self-healing propensity obviate the need for expensive make use of raw materials as cheap and commonplace as and time-consuming repair work, it can also signifcantly salt and yeast extracts, and are capable of recycling waste reduce the cost of concrete structures by enabling engineers products such as urea. BE to dispense with steel reinforcement, which is the more traditional method used to prevent cracks from becoming too large.SERC is also developing an innovative, cost- effective method for the production of high-performance See more at: http://sourceable.net/development-self-healing- thin sheeted, fabric-reinforced cement composites. concrete-moves-closer/#sthash.2WtZBqhG.dpuf PG 24 Built Expressions Vol: 3 Issue: 11 November 2014