Thursday, June 27, 2013

Why Asphalt?

Why Asphalt

Why_AsphaltThere are many reasons that highway engineers and motorists prefer asphalt. Simply stated, asphalt pavements are designed and built to last. Most roads are constructed in layers, with each layer playing its part in delivering the best infrastructure possible. When it’s all put together, asphalt pavements can handle the toughest traffic punishment.

Perpetual Pavements

An asphalt Perpetual Pavement is designed and built to ensure that the structure lasts virtually indefinitely. Routine maintenance is simply a matter of periodically milling (about every 12 to 20 years) the surface for recycling, followed by placement of a new, smooth new overlay. Not surprisingly, these periodic overlays significantly improve the ride quality and fuel consumption of vehicles traveling these roads. Bottom line: Throughout its life, an asphalt pavement’s ride and performance are just as good as new.

Smoothness 

Studies have demonstrated the fact that pavement smoothness is a significant determinant of vehicle fuel economy. The smoother the pavement, the lower a vehicle’s fuel consumption. But which tends to be smoother, asphalt or concrete? Well, one indication comes from state DOTs’ standards, which have specifications for newly built roads. If the road does not meet the standard, the contractor’s pay is reduced. Some states have different standards for asphalt and concrete, and in every state where this is the case, the requirements for asphalt roads are more stringent than for concrete roads.

Smoother pavements also last longer because trucks’ tires roll more easily along the pavement instead of bouncing on bumps – and such bouncing actually accelerates road deterioration. Studies show that improving pavement smoothness by 25 percent results in almost a 10 percent increase in pavement longevity. Smooth roads don’t just save taxpayers money by lasting longer, they also conserve precious natural resources.

Quiet pavements

Noise, including road noise, is a pervasive form of environmental pollution. There is no better way to reduce road noise than to treat the problem at its source. By paving roads and highways with asphalt, the noise generated by at the tire-pavement interface – noise that affects people as they go about their daily lives – can be significantly reduced. Paving with asphalt is actually more effective than building expensive, unsightly noise walls.

Speed of construction

Paving with asphalt cuts construction project time significantly and eliminates the long curing times of concrete. As a result, traffic flows more smoothly and impact on commerce is minimized. Asphalt paving projects can be planned and carried out to take advantage of off-peak periods, like nights and weekends. Asphalt is ready for traffic right after it is compacted and cooled, meaning that roads don’t have to remain closed for curing. This enhances traffic flow and minimizes closures and delays that frustrate motorists and cost money.

Maintenance is quick, cost-effective, and less disruptive than with concrete pavements.

Versatility
Asphalt is best for parking lots, and for such specialized applications as airports and racetracks.

Parking lots
Asphalt is an economical, environmentally friendly, fast-to-construct material for parking lots. About 85 percent of the parking lots in the U.S. are asphalt.

Airports 
Busy commercial airports such as Baltimore-Washington International, Oakland International, San Francisco International, McCarran (Las Vegas), Pearson International (Toronto), and Logan International (Boston) have main runways surfaced with asphalt. Boston Logan's airport has paved a runway with warm-mix asphalt, making it one of the greenest airports in the world. Asphalt is also used on 85 percent of the runways at general aviation airports. Asphalt's speed of construction makes it an ideal choice for rehabilitation of busy aviation facilities.

Race tracks
Asphalt pavements provide smooth driving surfaces combined with the excellent traction demanded by professional stock car racing. Of the 33 NASCAR race tracks across the country, 31 are paved with asphalt. Of the 88 race tracks listed for the NASCAR Short Track series, 64 are asphalt, 21 are dirt or clay, and only three are concrete.

Wednesday, June 26, 2013

Utilities in Rhode Island detected using Ground Penetrating Radar

Utilities in Rhode Island detected using Ground Penetrating Radar 



Infrasense_gI_97830_DSCN7060Infrasense recently completed a project to locate embedded utilities and determine pavement thickness for a three-mile section of road in Rhode Island.
The project incorporated both vehicle and walking-based surveys using Ground Penetrating Radar (GPR). As a result, no cores or test pits were used to obtain utility location information.
A majority of the survey utilized a vehicle-based system, operated at close to driving speed, to minimize disruption to traffic flow. The information obtained will facilitate planning efforts associated with the safe installation of a fiber-optics utility line. It is important for the project planners to understand the in-situ conditions, including the pavement thickness and utility locations, to plan a proper rehabilitation of the roadway and mitigate the risk of damaging existing utilities.
The field work was carried out by Infrasense on the three-mile section of roadway in just one night. Despite the thickly settled location of this section of road, which carries relatively high traffic volume between Bristol and Warren, the surveys were performed without causing any traffic disruptions or backups. In order to detect all utilities and assess the pavement structure, Infrasense engineers used both walking and vehicle-based surveys. To detect utilities that are buried transversely across the road width, data was collected along the length of the road using the vehicle-based system. To detect utilities buried longitudinally along the length of the road, data was collected across the width of the road with the walking survey system.
Ground penetrating radar is a nondestructive evaluation technique that operates by transmitting short pulses of electromagnetic energy into the concrete or asphalt pavements, using a boxed antenna attached to a survey vehicle or rolled along the pavement. These pulses are reflected back to the antenna providing a record of the properties and thicknesses of the layers within the pavement. GPR can detect the depth and spacing of utility lines or other metallic objects, as well as the thickness and reinforcing steel of concrete slabs.
It is also able to detect subsurface deterioration of a slab through changes in the radar signal through the concrete. The variety of GPR configurations and settings allows for adaptation to the unique constraints of many different utility projects.
- See more at: http://www.betterroads.com/infrasense-detects-utilities-in-rhode-island-using-ground-penetrating-radar/#sthash.cqH22dMd.dpuf

Thursday, June 20, 2013

Recycling Asphalt

Recycling Asphalt

What is Recycling asphalt?

Recycled asphalt is the material removed from damaged road surfaces and roofing materials
Recovered asphalt is a feed stock in the manufacture of new asphalt. It typically has a 5 percent concentration in the new asphalt, though this proportion may rise to 30 percent. It is a surface for minor roads such as farm roads or private driveways. Asphalt road surfaces damage periodically due to foundation subsidence, drainage problems or surface adhesion failure. The surface hardens cracks and crumbles over time. The chemical composition of asphalt does not change. The removal of the damaged surface using pneumatic or hydraulic breakers produces a waste product called road planning. The asphalt in these planning is a granular material compared with the continuous texture of new asphalt. Asphalt is 100% recyclable over and over.

In time for Earth Day, NAPA and FHWA have released a new survey of sustainable construction practices in the asphalt pavement industry. The survey, which covers the 2011 construction season, studies the usage of reclaimed asphalt pavement (RAP), recycled asphalt shingles (RAS), and warm-mix asphalt (WMA). The use of recycled materials in asphalt pavements saved taxpayers more than $2.2 billion dollars during the 2011 paving season.

According to the survey, about 21.2 million barrels of liquid asphalt binder were saved through the use of RAP and RAS during 2011. As early as 1993, the Environmental Protection Agency and Federal Highway Administration identified asphalt pavement as America’s recycling # 1 product in the USA. A wide range of waste materials are now incorporated into asphalt pavements, including ground tire rubber, glass, foundry sand, slag, and even pig manure, but the most widely used are reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS). The use of recycled materials in asphalt pavements saves hundreds of millions of cubic yards of landfill space each year.

Asphalt producers have been recycling for more than 30 years and recycled asphalt pavement (RAP) has become the number one recycled material in the US with about 67 million tons recycled in 2011. Despite this impressive record in many areas of the country there is more RAP available than can be used. The limiting factors range from specification limits and equipment capabilities to process/quality control.



Sealcoating

Sealcoating

Sealcoating is one of the most important elements of a pavement management plan.  A sealcoat consists of either coal tar pitch or asphalt cement mixed with inert fillers, water, emulsifying agents, or additives. Applied in thin coats, pavement sealing is used to protect off-highway pavement surfaces against gasoline, oil, salt, water, and ultraviolet rays.

Sealcoating Benefits

Beautification
When covered with a dark black sealant, pavement looks and wears like new. Parking lot sealcoating helps to project a positive image of the company, facility, or residential complex.
Slows oxidation and water penetration
Sealcoating fills surface voids, which reduces exposure to oxygen and UV rays and reduces the depth to which oil or gas can penetrate the pavement.
Sealcoating acts as a waterproofing agent, minimizing the rate at which water enters pavement. Without it, water can permeate more freely resulting in freeze/thaw expansion and contraction of the pavement.
Sealcoating resists oil and gas spills
Gasoline dripping from a topped-off fuel tank during hot weather can soften and break down unsealed asphalt pavements. Coal tars used in sealcoat are impervious to gas and oil spills.
Asphalt sealcoating is easier to clean and maintain
Sealcoats fill surface voids while coating the pavement surface. The resulting smooth and even texture makes the surface easier to maintain year-round. For example, snow is easier to remove from a smooth surface, and sweeping is far more effective on a smooth surface.
Sealcoating increases pavement flexibility
Sealcoat brings a dark black color to the pavement. The blacker it is, the more heat a pavement draws from the sun.  And, the hotter it gets, the more pliable it becomes, which helps it to withstand traffic without cracking.
Protects asphalt from pressure washing
Restaurant parking lots often extend to areas near dumpsters, where food-processing machines are pressure washed. Food waste near the dumpsters may also need to be washed away if it can't be swept away. Sealcoating protects asphalt cement from the high-volume water pressure and detergents used in pressure washing.
Asphalt sealcoating is cost effective
The price of asphalt will always be affected by crude oil prices, which fluctuate when supplies vary. Sealcoating preserves asphalt for pennies per square foot.

Tuesday, June 18, 2013

Talking About Asphalt

Asphalt is a mix design of different aggregates(stone,sand etc.) and Asphalt cement or asphalt liquid plus some manufactures use RAP (recycling asphalt).In an asphalt plant the aggregates will be dry by a burner and added to the mixing drum with the asphalt liquid and the RAP.The difference on mixes are the use for them . Base mixes normally has 1/2'' stone or bigger and mixes for the surface are made with 1/2 '' stone or smaller.For a small job as a Driveway is recommended 2'' inches or more in top of a processed gravel base or a course base asphalt mix minimum of 2''.If you are going to pave asphalt in top of existing asphalt you will need a primer or tack coat to better results.  

Friday, June 14, 2013

Moratorium puts plans for asphalt plant on hold

WESTERLY — A nine-month moratorium on the acceptance of new applications for industrial or commercial projects within close proximity to public water wells and other sources of the town’s water supply is in place following a unanimous vote Thursday by the Town Council.

The moratorium was the council’s response to the hundreds of Westerly and Pawcatuck residents who asked in person and through a 240-name petition for the town to intervene and block Cherenzia Companies plans for a 300-ton per hour asphalt plant at the end of White Rock Road on land that the company currently uses for a sand and gravel operation.

Thursday, June 13, 2013

The History of Asphalt

The History of Asphalt
Historic asphalt pavingThe story of asphalt begins thousands of years before the founding of the United States. Asphalt occurs naturally in both asphalt lakes and in rock asphalt (a mixture of sand, limestone and asphalt).

The ancient Mesopotamians used it to waterproof temple baths and water tanks. The Phoenicians caulked the seams of their merchant ships with asphalt. In the days of the Pharaohs, Egyptians used the material as mortar for rocks laid along the banks of the Nile to prevent erosion, and the infant Moses' basket was waterproofed with asphalt.
625 B.C.
The first recorded use of asphalt as a road-building material in Babylon. The ancient Greeks were also familiar with asphalt. The word asphalt comes from the Greek "asphaltos," meaning "secure." The Romans used it to seal their baths, reservoirs and aqueducts.
1595
Europeans exploring the New World discovered natural deposits of asphalt. Sir Walter Raleigh described a "plain" (or lake) of asphalt on the island of Trinidad, near Venezuela. He used it for re-caulking his ships.
Early 1800s
Thomas Telford built more than 900 miles of roads in Scotland, perfecting the method of building roads with broken stones. His contemporary, John Loudon McAdam, used broken stone joined to form a hard surface to build a Scottish turnpike. Later, to reduce dust and maintenance, builders used hot tar to bond the broken stones together, producing "tarmacadam" pavements.
1870Belgian chemist Edmund J. DeSmedt laid the first true asphalt pavement in the U.S. in Newark, N.J. DeSmedt also paved Pennsylvania Avenue in Washington, D.C. – using 54,000 square yards of sheet asphalt from Trinidad Lake. The Cummer Company opened the first central hot mix production facilities in the U.S. The first asphalt patent was filed by Nathan B. Abbott of Brooklyn, N.Y. in 1871.
1900
Frederick J. Warren filed a patent for "Bitulithic" pavement, a mixture of bitumen and aggregate ("bitu" from "bitumen" and "lithic" from "lithos," the Greek word for rock). The first modern asphalt facility was built in 1901 by Warren Brothers in East Cambridge, Mass.

Paving Project start in Providence

Paving project starts in Providence

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May 10, 2013 8:22 am
By Business staff
The first stretch of paving is being done in a project that will see 65 miles of roads in Providence resurfaced.
Mayor Angel Taveras is launching the city-wide road improvement project on Friday morning in lower South Providence. City councilman Luis Aponte, who represents the area in Ward 10, is also scheduled to attend.
The work will begin along Gallup Street.
The mayor has estimated that the project to repave about 15 percent of city-maintained roads will create about 750 jobs over three years. The work is being funded by over $39 million in bonds approved by voters last fall and sold earlier this year. (Associated Press)

North Kingstown,Rhode Island


Rhode Island Roads

RI roads riddled with potholes

Potholes damaging RI'ers vehicles

Updated: Monday, 24 Jan 2011, 5:54 PM EST
Published : Monday, 24 Jan 2011, 5:53 PM EST
PROVIDENCE, R.I. (WPRI) - Roads around Southern New England are plagued by potholes.
This winter's snow, ice & freezing temperatures are a perfect storm that has caused streets to quickly deteriorate.
On Valley Street in Providence's West End, potholes are forcing drivers to swerve to avoid damaging their cars.
"They are full of water until you get up on them, then the tires hit and they sink in," Albert Latour of Latour Auto Body told us Monday.
One small pothole could cause damage that costs big bucks to repair.
"It could be up to $500 to $800 range," Latour said.
Potholes are a fact of life on New England roads.
The use of plows to keep streets clean following snow are to blame for much of the damage.
"I would suspect that it would get worse," Latour said. "You can't keep up on them."
Providence Mayor Angel Taveras tells Eyewitness News that maintaining roads is a top priority for his administration.
The Mayor asks anyone who spots a pothole to call the Office of Neighborhood Services to report it.
If your car is seriously damaged by a pothole, you should file a police report and a claim with your community within 7 days of the incident.