Posted by Jesse Willoughby on Wed, Mar 31, 2010 @ 01:23 PM
Here is a recent trench we completed in Newark, CA on Cedar Blvd. Check out the quick video shot of our crew working.
Posted by Jesse Willoughby on Thu, Oct 15, 2009 @ 11:10 AM
Cracking Repairable with Sealant or Fill
Asphalt cracks that form in the pavement surface can allow many harmful substances - including water, salts and engine oils - into the base and subgrade, effectively leading to the failure of the pavement surface. There are many types of asphalt cracking and many causes for these differing problems. In many cases, cracks develop because of the expansion or contraction of the base or subgrade or because of voids that form between the layers or courses of pavement. These cracks can form randomly or in the following specific forms. In all cases, if repaired while still within ¼" to ½", these cracks are easily repaired and maintained.
Transverse cracking
Transverse cracking, or cracks that occur across the pavement surface about perpendicular to the parking lot center, are often caused by the asphalt expansion and contraction due to temperature changes and or this movement due to asphalt aging. Initially, these cracks will be relatively equally spaced depending on traffic but will eventually become more prevalent in the parking lot or roadway. In some cases, as these cracks become more prevalent, block cracking forms where the Transverse cracks develop into squares throughout the pavement.
Also, these cracks may extend either entirely or partially across the pavement area or roadway.
Transverse cracks begin as "hairline" cracks - or cracks up to ¼" wide - but will widen to ½" or wider with age and lack of proper repair. Because these cracks are allowing water into the pavement base and subgrade, lack of proper asphalt repair or maintenance will lead to more cracks developing parallel to the original transverse cracking. If not properly repaired, these transverse asphalt cracks will be appear with greater prevalence and the cracks will become wider; eventually, the cracks will be so prevalent that entire areas will be broken or "alligatored" (see Alligatoring section) leading to a more serious, cutting and patching asphalt repair.
Next we'll cover longitudinal asphalt cracking...
Source: U.S.Pavement Services
Posted by Jesse Willoughby on Mon, Sep 14, 2009 @ 02:24 PM
Sometimes Asphalt is better than concrete, and life-cycle costs can be one of those benefits where you'll save money.
- Reduces costs for initial construction.
- Requires less maintenance over the life of the pavement.
- Repaired and maintained cost-effectively with HMA overlays instead of complete removal and reconstruction with concrete.
- When maintenance is needed, HMA offers the widest variety of alternatives geared to solve the precise problems on the surface.
- Can be overlaid to add structural capacity to account for increased traffic loading.
- Eliminates the need for costly reinforcing materials, which are subject to corrosion, which lead to more frequent and more costly repairs.
- Properly designed and constructed HMA pavements will last 50 years or more with occasional resurfacing, relieving road agencies of the need for costly, time-consuming and disruptive reconstruction.
- HMA can be recycled (milled and replaced along with fresh materials), saving dollars and preserving nonrenewable natural resources.
Posted by Jesse Willoughby on Sat, Aug 15, 2009 @ 08:29 AM
There are many reasons to use asphalt for your pavement surface. One of the reasons is its cost effectiveness, which right now is a great reason to use asphalt. Often asphalt is 1/2 or 1/3 less than Concrete.
Today's Hot Mix Asphalt is a high-tech product that can withstand enormous traffic loads ranging from 18-wheelers to commercial airliners. It is a highly versatile product that can be used for many applications-from Interstate highways to airport runways, parking lots, bicycle trails, and private driveways.
There are seven reasons why most engineers who have closely studied the new high-performance asphalt are convinced that it should be the pavement of choice for designers of future roadways...
Click here to read the 7 reasons.
Posted by Jesse Willoughby on Fri, Aug 14, 2009 @ 07:24 AM
1. A well-surfaced and striped asphalt parking area demonstrates your care for overall safety and aesthetics of your property. Maintaining a healthy parking area attracts and retains tenants and customers.
2. Sound maintenance of asphalt extends the life of a parking facility, decreasing your overall repair costs and improving the return on the investment of your property. Just as the exterior of a building or any painted surface needs preventative maintenance to prolong its life and reduce the cost of ownership the same is true with asphalt.
3. The constant weight of a parked or slow moving vehicle is greater than a faster moving vehicle. Stresses placed on asphalt in parking lots often exceed the loads experienced on highways and streets. Stay educated about distress signals and take appropriate remedial action.
Posted by Jesse Willoughby on Wed, Aug 12, 2009 @ 04:57 PM
Pavement Markings Issues
Pavement marking effectiveness is based mostly on the durability and the visibility of the markings. Durability is
usually tracked by the simple amount of material remaining on the pavement surface over time, but can be more
scientifically tracked by measuring the bond strength of the material to the surface. Visibility related mostly to the
brightness and reflective nature of the material. Glass beads mixed into the pavement marking traffic grade paint
can add to the visibility by greatly increasing the material's retro-reflection characteristics.
Fading
Faded pavement markings and parking stall lines make these important traffic control devices invisible to
customers, tenants and other motorists, leading to potentially dangerous outcomes. Arrows, stop bars, and other
traffic control markings ensure the proper flow of traffic and optimize customer flow in and out of parking lots. Fire
lanes, curbing and no parking zones ensure that vehicles will not be parked in important areas and potentially
block emergency response vehicles. Furthermore, faded parking lines lead to insufficient use of parking lot space
and leading to less customer and tenant parking than the parking lot space will allow, including accessible parking
spaces.
Pavement Markings on Fresh Sealcoat
Although thermoplastic paint are the ideal type of pavement marking on sealcoated surfaces, water-based or
latex-based paints are far more economically feasible relative to their durability and visibility. Water-based or
latex-based traffic grade paints must be applied, however, after the sealcoat has properly cured; this curing can
take as little as a few hours depending on sun exposure, humidity, traffic conditions and other variables. If
sufficient curing time is not allowed for the sealcoat, traffic grade paint will being to "bleed" and discolored.
Furthermore, excess traffic on fresh sealcoat will also "scar" the pavement markings with tacky sealcoat that has
come onto vehicle tires and is tracked onto fresh pavement markings. All of these potential issues can be
avoided by allowing sealcoat proper dry times before applying pavement markings.
Posted by Jesse Willoughby on Mon, Jul 13, 2009 @ 12:48 PM
Every state has committed at least half its highway stimulus funds so none will lose any of its allocation, the Obama administration said Thursday.
States had until June 29 to obligate the funds or risk losing half the leftover money. Only a month ago, some 14 states had yet to satisfy that goal. Hawaii was the last to meet the mark, hitting it on June 19.
Maine has secured 100% of its funds and 15 states have more than 80% of their money committed.
read more
Posted by Jesse Willoughby on Thu, Jun 04, 2009 @ 04:50 AM
Recycling
Hot Mix Asphalt gives the best return on investment of any paving material. But beyond just having that fact that it saves money, it also has environmental benefits.
Because the main ingredient in asphalt is oil, its price has increased dramatically in the last several years. Five years ago, government agencies paid $35 to $40 a ton for asphalt. However, now the price has escalated to over $90 a ton, and it is predicted that the price of asphalt will continue to climb. This has led to an increased demand for recycled asphalt which is lower in price and widely available. Asphalt and tar recycling has also become more popular because of environmental concerns. Recycled asphalt simply produces a less negative environmental impact because it is not being placed in landfills.
Hot Mix Asphalt(HMA) pavements are 100 percent recyclable and are America's most recycled product. Approximately 80 million tons of Hot Mix Asphalt are recycled each year. Compare this to any other recycled products. Hot Mix Asphalt pavements are truly environmentally friendly.
HMA pavement recycling is more cost effective than using only virgin or new materials. The quality of a recycled asphalt pavement is as good, or even better, than brand new pavement.
Hot Mix Asphalt pavement recycling not only conserves our precious natural resources and speeds construction, it also saves American taxpayers over $300 million a year.
HMA pavements which are not recycled must be disposed of, usually in a landfill. Transporting old asphalt pavements to landfills does not make best use of a product that can be recycled. HMA pavements can be recycled numerous times.
Currently, even most new asphalt has between 15 and 20 percent of crushed, recycled asphalt mixed into it. Because of this, asphalt has now surpassed aluminum as the most widely recycled material in the world.
ASPHALT IS AN ENVIRONMENTALLY SOUND PRODUCT
Environmental Liners
Asphalt paving materials have been used to line the surfaces of everything from fish hatcheries to industrial retention ponds. In the case of fish hatcheries, an inert material was needed that would not chemically react with the water. This allows fish and game experts to precisely monitor and control the environment during the delicate stages of incubation and early growth for various fish species.
- For example, Oregon and Washington state fish and wildlife agencies began using HMA to line their fish rearing ponds in 1987. Typically 1/2-acre in area, the ponds are home to chinook salmon and other fry for about 18 months before the fish are released into rivers and streams. Both the Washington and Oregon state agencies are pleased with the effectiveness of the HMA liners and plan to use them for additional fish hatcheries in the future.
For decades asphalt paving materials have been used as liners for water reservoirs.
- For example, The Metropolitan Water District of Southern California (MWDSC) has been using HMA-lined water reservoirs for more than four decades. Currently, the California Water Resources Board is completing construction on the Devil's Canyon Reservoir to store MWDSC drinking water. The 1 9-inch thick asphalt liner for the huge facility will hold 800-acre-feet of water. The East Bay Municipal Utility District (EBMUD) in Oakland, California, has also been using HMA to line domestic water supply reservoirs since the 1 950s. A total of ten reservoirs store water in the EBMUD system.
Asphalt binders have also been used to line water pipes that supply potable water to humans.
When used for industrial retention ponds, the inertness of asphalt paving materials keeps liquid industrial waste material from percolating into the soil. This gives industry time to treat the liquid waste, and if needed, provides a platform with which to bring in mobile equipment to move the material to a processing location.
The ability of asphalt paving materials to be both chemically inert and strong enough to provide a structure for heavy equipment accounts for its use as both a landfill liner and cap. In landfills lined with asphalt paving materials modified earthmoving equipment can be employed to organize and compact landfill waste without fear of breaking the impermeable shell between the solid waste material and the soil.
Clean fill
Many states have tested discarded asphalt pavement and determined that it should be categorized as clean fill.
Even the Environmental Protection Agency's Toxicity Characteristics Leaching Procedure (TCLP) test, their most extreme and rigorous test for determining the toxicity of a substance, failed to show any appreciable quantities of toxic materials from asphalt pavement material.
Recreational Uses
HMA pavements are a perfect fit for the recreational industry. For years HMA has been used to pave running tracks, bicycle and golf cart paths, in addition to its traditional use for basketball and tennis courts.
Recently, there has been a move in the recreation marketplace to combine exercise with nature. Throughout the country old nature paths and abandoned rail lines are being converted into thoroughfares for bicyclists, roller skaters and roller bladers, besides the occasional pedestrian who wants to view nature while they exercise.
Asphalt pavements provide a safe and durable surface with which to accommodate both wheeled and foot traffic.
Other Uses
HMA is also used to pave cattle feed lots, poultry house floors, barn floors, and greenhouse floors. Asphalt not only provides an all-weather platform, it also provides protection against disease from waste materials. Asphalt is easy to clean and prevents pollution from getting into water supplies.
Asphalt mixtures are also used in sea walls, dikes and groins to control beach erosion. Its strength, waterproofing capability and inertness to sea water helps prevent the eroding action of tides and waves.
Posted by Jesse Willoughby on Mon, Jun 01, 2009 @ 05:40 AM
Crosswalks
On roads where traffic is not controlled by signals or
stop signs, crosswalk markings warn the motorist of a
pedestrian crossing point. On controlled intersections,
crosswalk markings primarily guide pedestrians in the
proper paths. Do not use crosswalk markings indiscriminately.
Only an engineering study should recommend
installing crosswalks where there are no traffic signals
or stop signs.
Crosswalk lines are two parallel solid white lines
normally spaced 6' (minimum) apart. They shall be a
minimum of 6" and maximum of 24" in width. Wider
lines may be considered when, for example:
• Traffic speeds are above 35 MPH.
• There is no advance stop line.
• Drivers don't expect crosswalks.
Colored pavements alone are not considered a traffic
control device. Crosswalk lines must outline them.
For added visibility, mark the area inside the crosswalk
with white diagonal lines at a 45-degree angle.
These lines should be about 12"-24" wide and spaced
12"-60" apart. Use these diagonal lines on crosswalks at
unexpected areas, where many pedestrians are crossing
without any other traffic control device, and where
physical conditions make added visibility desirable.
Pedestrian crossing signs are also useful. Zebra stripes
(lines longitudinal to traffic flow) provide added visibility
and target value especially at roundabouts. See the
roundabout photo on page 6, for an example.
Railroad crossings
Special pavement markings are required before railroad
crossings with signals or automatic gates and at all
crossings where the prevailing speed of highway traffic
is 40 MPH or higher. Railroad
crossing pavement markings may be omitted in special
situations such as:
highway speed limit or prevailing speed is 35 MPH or
less and there are no active RR warning devices, or
• track is a minor spur where trains operate at 15 MPH
or less, or
• approach distance is less than 250' rural or 100' urban.
Pavement markings before a grade crossing are an
"X" with an "RR" behind them. A wide line is placed
above and below the "X". Identical markings must be
placed on each approach lane. All markings should be
white and reflectorized. Stop bars must extend from the
centerline to the edge of the pavement at 90 degrees to
the direction of travel. Place the W10-1 round RR warning
sign at the first cross line. A stop bar at railroad
tracks should be no closer than 25' from the nearest rail.
Posted by Jesse Willoughby on Sun, May 31, 2009 @ 05:30 AM
Edgelines
Pavement edgeline markings give drivers a guide to the
edge of the pavement and also enhance safety. A study
of rural highways in Kansas showed that edgelines will
yield benefits exceeding their costs if an average of one
non-intersection crash occurs annually every 15.5 miles
of roadway. Edgelines are a particularly valuable visual
reference during bad weather and poor visibility, especially
along curves. They can also be used to mark the
pavement edge to reduce driving on paved or unpaved
shoulders. Break edgelines for intersections, major
driveways or interchanges. Continue edgelines through
minor driveways unless a full width turn lane has been
provided. Wide solid edgeline markings may be used
for greater emphasis.
Required (shall)
• Rural arterials 20' or more in width and 6000 vehicles
per day or more.
• Freeways and expressways.
Recommended (should)
• Rural arterials and collectors 20' or more in width
and 3000 vehicles per day or more.
Optional (may)
• Other paved streets based on engineering study.
Channelizing lines
Channelizing lines can be used to form channelizing
islands where traffic is going in the same direction on
either side of the island. They shall be a wide or double
wide solid white line. White diagonals or chevron marking
can be placed between the channelizing lines for
greater emphasis.
Yield lines
Yield lines are white and shall
consist of a row of solid white
isosceles triangles pointing
toward approaching traffic.
They are not required, but
may be helpful at roundabouts,
mid-block crosswalks, or other
locations with yield signs.
Stop lines
Stop lines are solid white lines and should be 12"-24"
wide. Stop lines emphasize the stop condition and
indicate where to stop. They are not required, but are
helpful in many situations. For example, visibility may
be better at a point closer to the intersection than the
stop sign can be placed. The stop line can be used to
show this to drivers. Stop lines should be a minimum of
4' in advance of a marked crosswalk. Do not use stop
lines with yield signs. Place no closer than 4' from the
nearest edge of the intersecting travel way and no more
than 30'.