A Research Paper on Porous Asphalt Pavement

The aim of this study is to recharge ground water to underplaying aquifers and reduce risk of flood condition. Porous asphalt pavement is an alternative technology that differs from traditional asphalt pavement designs, that the pavement permits fluid to pass freely through it. Porous asphalt pavement also reduces and control surface runoff of surrounding area. This technique also can be used as additional way of storm water management. The past few studies suggests that, porous asphalt pavement intended to be used for parking lots, storm water management, water quality treatment, peak flow reduction and noise control. The research has focused on improving quality and quantity of ground water. This study includes model making and checking performance of that constructed pavement model. Study investigates performance of aggregates and porous asphalt used in projects, such as properties of aggregates like impact value, crushing value, specific gravity, abrasion test. Tests performance on porous asphalt includes ductility test, stripping value test and penetration test. Study includes sample making of various proportion of asphalt and aggregates. Total 9 samples were made to check which sample gives best performance as per the requirement. Out of 9 samples, 6% asphalt with 10mm aggregate + grit sample gives required performance.

The aim of this study is to recharge ground water to underplaying aquifers and reduce risk of flood condition. Porous asphalt pavement is an alternative differs from traditional asphalt pavement designs, that the pavement permits fluid to pass freely through it. Porous asphalt pavement also reduces and control surface runoff of surrounding area. This technique also can be used as additional ter management. The past few studies suggests that, porous asphalt pavement intended to be used for parking lots, storm water management, water quality treatment, peak flow reduction and noise control. The research has focused on improving tity of ground water. This study includes model making and checking performance of that constructed pavement model. Study investigates performance of aggregates and porous asphalt used in projects, such as properties of aggregates like impact ng value, specific gravity, abrasion test. Tests performance on porous asphalt includes ductility test, stripping value test and penetration test. Study includes sample making of various proportion of asphalt and aggregates. Total 9 samples were made eck which sample gives best performance as per the requirement. Out of 9 samples, 6% asphalt with 10mm aggregate + grit sample gives required Crushing strength, Impact value, Ductility, Porous asphalt (PA) also namely open graded asphalt has been use as a wearing surface since the 1950s. Its first major use in Australia was about 1973 and in Japan was about 1987. Porous asphalt is an innovative road surfacing technology which allows water into the asphalt mixes beyond its continuous air voids, several studies are quantified high removal rates of total suspended solids, metals, oils, and grease, as well as moderate removal for phosphorus, from using porous asphalt pavement. Por with stone reservoirs are a multifunctional, low impact development technology that ecological and environmental goals for a site with land development goals, reducing the net environmental impact for a project.
Not only do they provide a strong pavement surface for parking, walkways, trails and roadways, they are designed to manage and treat storm water runoff. With proper design and installation, porous asphalt pavements can provide a cost storm water management in an environmentally friendly way.
Porosity of the asphalt mastic is usually between 15 and 20 percent. The sub-base layers may include water storage systems or normal pavement structure as used also under impermeable surfaces (overlay structure). Functionality of the porous asphalt pavement is the same as that of other pervious pavements. Storm water infiltrates to soil through pavement layer and it reduces ponding and need of sewer systems. Effects on friction and hydrological systems are positive. Additional benefits are also noise reduction, which is desirable feature in residential or high trafficked area and better visibility when there is hydroplaning, spraying and light reflection results. This proven concept of building porous asphalt pavements was declared Outstanding Japan was about 1987. Porous asphalt is an innovative road surfacing technology which allows water to enter into the asphalt mixes beyond its continuous air voids, several studies are quantified high removal rates of total suspended solids, metals, oils, and grease, as well as moderate removal for phosphorus, from using porous asphalt pavement. Porous asphalt pavements e a multifunctional, low development technology that integrate ecological and environmental goals for a site with land development goals, reducing the net environmental impact for a project. they provide a strong pavement surface for parking, walkways, trails and roadways, they are designed to manage and treat storm water runoff. With proper design and installation, porous asphalt pavements can provide a cost-effective solution for management in an environmentally Porosity of the asphalt mastic is usually between 15 base layers may include water storage systems or normal pavement structure as used also under impermeable surfaces (overlay re). Functionality of the porous asphalt pavement is the same as that of other pervious pavements. Storm water infiltrates to soil through pavement layer and it reduces ponding and need of sewer systems. Effects on friction and hydrological itive. Additional benefits are also noise reduction, which is desirable feature in residential or high trafficked area and better visibility when there is hydroplaning, spraying and light reflection results. This proven concept of building pavements was declared Outstanding

II. LITERATURE REVIEW 1)
Indian Road Congress Journal, "Indian Highways" The Jaipur Development Authority (JDA) had planned to construct a conventional dense graded asphalt parking lot at the Gandhi Nagar Railway Station in Jaipur. It was decided to include an experimental porous asphalt area (about 85 m by 4 m) as part of the large parking lot. It is believed to be the first ever porous asphalt pavement constructed in India for rainwater harvesting. According to the 2004 data of CGWB, for every 125 units of ground water being taken out in Jaipur, only 100 units are replenished by rain. It is estimated that the ground water level in Jaipur is falling at the rate of about one meter every year.

2)
Danish Road Institute A brief historic summary of the development of porous asphalt is provided by Kraemer at the opening of the European Conference on Porous Asphalt in Madrid in 1997 [17]. Originally developed to prevent skidding on wet pavements in the thirties in the US porous asphalt was ready for general applications on highways and airports in the seventies. This was the basis for the European development of porous asphalt in the early eighties based on the research at the University of Cantabria where a mix-design method for porous asphalt was established. In 1985 the operational use on motorways and major roads began and a rapid development took place especially when the noise reducing benefits was recognised.

3)
University Of New Hampshire Stormwater Center Journal(UNHSC) This specification is intended to be used for porous asphalt pavement in parking lot applications. Stormwater management functions of porous asphalt installations include water quality treatment, peak flow reduction, storm volume reduction via groundwater recharge, and increased hydrograph time lag. This specification is intended for a cold climate application based upon the field experience at the UNHSC porous asphalt parking lot located in Durham, New Hampshire, however the specification can be adapted to projects elsewhere provided that selection of materials and system design reflects local conditions, constraints, and objectives.

III. EXPERIMENTAL PROGRAM
Experiments were conducted on porous asphalt and aggregate. Samples are made using various proportions (4%, 6%, 7%) of porous asphalt of the total weight of aggregate. Out of these 9 samples, we choose sample which gave better and controlled performance.

IV.
OBJECTIVES OF THE RESEARCH  To reduce risk of flooding situations and increase safety of drivers during wet weather.  Recharges ground water to Underlaying Aquifers and improving water quality by filtering pollutants in the substrata layers.  To Reduce splash and spray from Travelling vehicle, Reduced Roadway noise. V.

MATERIALS USED  Porous Asphalt
Polymer Modified Bitumen grade 40 was used in the design mix. The 6% asphalt was added for the final pavement model.    Abrasion value of aggregate forpavement is upto 20%. Hence above samples should be useful for road surfacing.

 Gravel
Gravel passed through 50mm and retained on 40mm sieve size for the reservoir bed. Pervious and impervious layer of geotextile sheets are used above the natural ground strata. We used 300 gsm geotextile sheet for the final model above the soil layer.
 Soil    From above table and graphs it is observed that, the sample made with 10mm size aggregate with grit give better and controlled performance instead of only 10mm size or only grit models. We chose 6% asphalt content + 10mmsize with grit sample mix for the final model for the top wearing course.

VII. MIX DESIGN OF CONSTRUCTED PAVEMENT
Ground water recharge Pipe system  UNCOMPACTED SUBGRADE These is natural ground strata. This layer is uncompacted only digging action is done on this layer at the time of large site taken in consideration. For model, we take layer thickness of these layer is 5mm and for the pipe system portion we give the slight slope for drainage purpose.
 GEOTEXTILE SHEET LAYER For ground water recharge portion, we use non-oven pervious geotextile sheet for infiltration of water below ground.
For pipe system portion we use non-oven laminated geotextile sheet which is impervious in nature.
 STONE RESEVOIR COURSE The function of the stone reservoir course is to temporarily store rainwater which percolates slowly into the natural subgrade below. We take the aggregate size for this layer is aggregate passing through 50mm sieve and retain on 40mm sieve. Thickness provided for this layer is 23cm.Perforated pipe is used for the pipe system portion for the drainage.
 STONE CHOKING COURSE The stone choking layer is placed on the stone reservoir course so as to fill and level its open large surface voids and to make it stable and smooth for asphalt paver. It was placed in 50 mm (2 inches) thick layer and compacted well with an 8-ton steel wheel roller in static mode only until a smooth surface was obtained for paving above it. Aggregate used for this layer is 16mm sieve passing and 12.5mm retain on sieve.

 POROUS ASPHALT WEARING COURSE
These is open graded and top asphalt layer of these pavement. The layer thickness provided for this layer is 60mm. The aggregate used for these layer as same as choking course layer. The asphalt used for this layer is 6% by weight of total mix of aggregate. The thickness ranges of layers are given in Indian Roads Congress Journal, "Indian Highways", Vol. 42 No. 3, March 2014].
VIII. CONCLUSION  Constructed pavement model has a negligible surface runoff hence it reduces the surface runoff and increase the safety of drivers and vehicles in wet weather, and also reduces drainage clogging problems.  In rainy season, the water is infiltrates from porous asphalt pavement and increases the water table level below the ground, we can use this water for various purposes or we can store this water for future use.  From this pavement the various type of pollutants are also infiltrates like oil, petrol liquid pollutants, because of this increases safety of vehicles and decreases possibility of accidents.