Short Memo: Aspects & Impacts of Porous Pavements The purpose of this short memo is to discuss aspects of use, applicability, and environmental impacts of porous pavements as gleaned from practical findings and pertinent examples. A porous pavement is one with high enough porosity and permeability to allow rain and snowmelt to pass through it, thereby reducing the runoff from a site and surrounding areas. In intensely built up areas, pavements account for more than half of all the land, and for about two-thirds of total built cover (Ferguson, 2005, 2-3). Parking lots, in particular, account for the majority of paved areas. Pervious paving materials have the capability of providing a dual purpose in parking and other areas with low to moderate traffic; they serve both as a parking/traffic area and to manage stormwater. Components & Function There are several types of porous pavements, namely porous asphalt, porous concrete, and numerous modular paver systems. Both a construction material and a design technique, systems may be used individually or enhanced through a combination of types. Porous asphalt consists of an open-graded coarse aggregate bonded together by asphalt cement. The mixture contains fewer fines than traditional asphalt and sufficient void space between aggregate particles allows water to drain through quickly. Porous concrete also consists of an open-graded coarse aggregate, formulated with Portland cement and water. Modular porous pavers are structural units, such as concrete blocks or reinforced plastic mats, with void areas that are filled with pervious materials, to achieve a load-bearing permeable surface. The pervious fill materials include sand, grass turf, and gravel. Each of these surfaces is typical... ... middle of paper ... ...rent purposes. Residential streets and interstate shoulders have been constructed of porous systems, and more extensive weight-bearing roads are functioning in Europe. More research and site study of porous paving techniques and specifications are needed to continue to increase knowledge and implementation of these systems, and to further their capacity for use. Works Cited Adams, Michele (May/June 2003). “Porous Asphalt Pavement With Recharge Beds,” Stormwater Magazine. www.forester.net/sw_0305_porous.html Ferguson, Bruce (2005). Porous Pavements. FL: CRC Press. Georgia Stormwater Management Manual (2001). “Porous Concrete.” Vol. 2, 3.3-33 - 3.3-40. Georgia Stormwater Management Manual (2001). “Modular Porous Paver Systems.” Vol. 2, 3.3-41 – 3.3-46. U.S. EPA (September 1999). Stormwater Technology Factsheet: Porous Pavement. Washington, DC: EPA 832-F-99-023.
When construction takes place, it is usually way before it is actually needed. Of course it is helping prevent dangerous and fatal occurrences but for the most part some of these changes can wait. Instead of spending so much money on our transportation category we should be putting more into education. “The money that the Federal Budget gives for education covers college aid loans, special education programs, free lunch to students in need, anti-discrimination efforts, research, and special programs” (Document D). Education is one of the most important things a person can have. ”
Parking Lot Striping: Parking lot striping and professional pavement markings can help improve the safety and appearance of your parking
Steeped in history and surrounded by a diverse range of natural beauty, Somerset is a popular destination for tourists. Given the importance of tourism to the local economy, city officials, homeowners and businesses rely on asphalt pavement to help make a good first impression on visitors and keep them coming back. Somerset residents know that asphalt pavement is fast to install and maintain, provides an extremely smooth ride, is long-lasting, looks great and is very cost-effective. Whether they need asphalt paving, crack repair, sealcoating, asphalt curbing, parking lot striping, asphalt milling, bumper blocks or any other asphalt-related service, they also know that they can count on APM for extraordinary results at affordable prices.
...believe that the state should consider putting more money into repairing roads, both gravel and highway, so they are useable. Many of the people who do not live in town and use the gravel roads everyday could benefit tremendously from this.
Introduction: Rainwater runoff, also called non-point source, is everywhere, especially in the artificial concrete communities that we live in. Rainwater runoff occurs after rain showers and thunderstorms, when the water flows down streets, sidewalks and gutters. There is so much rainwater runoff now a day because of the colossal neighborhoods and buildings and parking lots we are creating. The runoff happens when the water can’t soak into the ground, like it naturally does. With growing cities and industrialization, runoff water is becoming more and more of a problem and people need to start worrying about it. Runoff water has the possibility of becoming very dangerous, depending on what the water takes with it. Pesticides, garbage, bacteria, sediments from roads, feces and oil/gasoline are just some of the many substances that rainwater runoff carries with it on it’s journey; and lets not forget about all of the possible toxic chemicals that would fall into its path. So many residencies have been built, causing more runoff water because it isn’t being absorbed into the soil, since the soil is covered in concrete or other substances that were used to build. Everything that rests in gutters also goes down into the soil and in sewers that dump water into soil or other bodies of water, and the effects can both be positive and negative. Substances such as phosphate can travel with the runoff water into areas with soil and grass, causing it to grow faster. While some people may think fast growing grass is helpful, lets not forget about the rest of the environment the phosphate can effect. Certain algae’s can be harmful to humans when ingested. After knowing that, people should realize that it is time for environmental management to co...
NCHRP 2004a Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures, National Cooperative Highway Research Program, NCHRP, Part 2– Design Inputs, Chapter 2 Material Characterization”.
Griffith, A. (1998). Improved winter pothole patching. Salem, OR: Oregon Dept. of Transportation, Research Unit.
In this report, we will introduce and illustrate on precast concrete, pre-stressed concrete, ready-mix concrete, reinforced concrete, terrazzo and Urbanite in details.
Bored piles construction is done using the suitable rotary drills depending on the diameter, depth, condition of the soil and construction method. Usually bore-holes are stabilized with a temporary or permanent casing. The common material used for the casing is steel and it is also normal called as steel casing. The length of the steel casing is also determined from the soil conditions that are discovered at the actual site.
One of the drawbacks of traditional pavement surfaces is that water cannot be drained and therefore an accumulation of water runoff develops and leads to flooding problems. This can be seen very regularly in the news, with the most recent flooding in South Carolina. Porous concrete is an effective and ideal solution for draining this water. Porous concrete has a high percentage of interconnected voids, which allow for the water to quickly percolate through the concrete instead of accumulating on the surface of it (Mulligan 14). This water is then soaked into the ground where it becomes groundwater and is used for wells and streams. There are two types of runoff mitigation using porous concrete, “passive” and “active”. A passive mitigation system is able to contain most of the water initially, but is not able to contain the excessive runoff from adjacent impervious surfaces. An active mitigation system is able to handle runoff from these impervious surfaces, however, the infrastructure should ensure that the flow of water does not bring in sediments and soil that may cause the voids in the porous concrete to clog (Tennis 11). When these voids are clogged the absorption of water is reduced, but this is able to be restored or even prevented with adequate maintenance. This maintenance includes activities such as snow plowing, using less salt in the winter (which will be okay because of the reduction in ice
Safdie, M 1966, Habitat, a design for high-density urban living, Cement and Concrete Association, London.
During my under graduation I have learnt only about basics of pavement materials and different layers of pavements. It was only after studying graduate courses I realized how limited my knowledge was and I need to work very hard and explore more in this vast field. During first year of my graduate study I have studied Pavements Materials, Pavement Design and Evaluation, Highway Construction Practices and these graduate courses opened a new paradigm for me to the way I looked at pavement engineering. This prompted me to look at it as a field full of challenges which make it even more dynamic and op...
Restoring and Improving Urban Infrastructure - Engineering Challenges. " EngineeringChallenges.org -. National Academy of Science, 2012. Web. The Web.
Gravel reminds me of city streets, lit up twenty-four hours a day and providing plenty of reason to hustle through the daily traffic jam. Specifically, I remember clearly how eons would pass by in cars, buses, or trains waiting to get home as the city became larger and longer. Strips of