Topic: Maintenance Mondays

How Long Does Asphalt Take To Dry?

One question we often hear at Calvac Paving is about asphalt cure times. This is a great question because understanding how the asphalt curing process works helps you understand when you can safely stripe, park, walk, and drive on the new asphalt parking lot and what sort of performance you can expect from your asphalt long-term. Let’s take a closer look at how the asphalt installation process works and how this affects the asphalt curing process!

 

Asphalt Surface Installation

 

Most asphalt paving companies prefer not to place a fresh asphalt surface if the ambient temperature is outside the range of  50°F-90°F. If it’s too hot, asphalt will not cure quickly enough.  Paving when it’s too cold can cause the asphalt crack as it rapidly cools. Weather conditions can make a difference as well. If you watch carefully, you’ll notice paving companies rarely place asphalt in heavy rain. While it is possible to pave asphalt outside these parameters, it requires special preparation and oversight.

The rules for hot asphalt patch, resurfaced asphalt sealcoating and cold patch asphalt placement are a little different, so for purposes of this discussion, we’re going to focus on a clean installation on grade for commercial or residential paving like parking lots or a driveway.  

 

 

How Long Does Asphalt Take to Cure?

 

The curing time for asphalt depends on the asphalt mix design, the oil content, the temperature of the mix, the thickness of the paved asphalt layers after compaction, and the temperature and weather conditions when the mix was placed. Generally, you can open new asphalt to public foot and vehicle traffic 48-72 hours after it is placed because this allows time for the asphalt to harden, but you may need to allow a bit more time during hot weather. Asphalt doesn’t fully cure for 6-12 months, so it’s important to keep a close eye on it during this time because it will be less resistant to damage.

The reason we stress the difference between “curing time” and “asphalt drying time,” even though they’re often used interchangeably is that asphalt is designed to be flexible. For it to remain flexible, it has to retain a certain amount of moisture. Water infiltration in paved asphalt driveways, parking lots, roadways, speed bumps, and other asphalt surfaces is the primary factor leading to a blacktop drying out. The water washes away the oil which keeps the asphalt overlay flexible and resilient. You can tell when asphalt dries because you’ll notice cracking, warping, raveling, and loose aggregate appearing on the surface of the matrix, especially sand and other fine aggregates. Fortunately, it takes months to years of asphalt drying time to start noticing signs other than cracking.

 

What Can I Do to Not Allow My Asphalt to Dry Out?

 

Good roadway and parking lot maintenance programs can help prevent a lot of problems. Putting down asphalt seal coating on a regular basis, especially when you freshen up your street or parking lot striping, can help prevent more costly asphalt repairs down the line. This is also a great time to do any basin repairs and crack filling, as catching these problems early, when they’re small, can keep your asphalt fresher and more flexible for a lot longer.

Asphalt sealer drying times vary, but 4-8 hours to dry is usually enough for your sealer to ensure it will keep water out. However, the full drying process for the sealer takes around 24 hours, and it’s important to allow your sealcoating to dry completely before line striping for maximum resiliency and effectiveness. As with any other kind of asphalt sealant, you want to allow crack sealer to cure for at least 24 hours in perfect conditions, and add a day for cool, cloudy, or high-humidity conditions just to be on the safe side.

 

Final Thoughts About How Long It Takes Asphalt to Dry

 

Of course, the best mix design in the world won’t do you any good if it’s improperly placed, if your striping doesn’t meet the latest ADA criteria or if you don’t take proper care of it. For the best possible results and the greatest confidence in your paving job from breaking ground to the final walkthrough and for years of use beyond, click here to contact Calvac Paving. We’ve been proudly serving the Bay Area since 1972 on residential, commercial, and government projects of all types. Our track record for consistent quality, service, and excellence in every aspect of our operations speaks for itself. Put our experience to work for your paving refurbishment, repair, or new construction needs and see why Calvac Paving is the contractor you need for paving that works the first time, every time!

 


How Many Parking Spots Will I Need For My Strip Mall?

Happy Monday Everyone! In this edition of Maintenance Monday, one of our social media friends sent us this question.  I own a strip mall in San Jose, we have 10 retail stores, with 75 parking spots. How do we figure out the correct amount of handicap parking spots to have?  The answer is…

Thank you, In this case, 75 stalls. Three would need to be accessible spaces (not handicap), of which one of those would have to be van accessible.  One thing to consider is the current count. If this property has 5 existing accessible spaces, it is best to put back those 5.  The reasoning is that the standards are the minimum and it is not usually a good idea to decrease accessibility on a property.  This is why it is important to plan these layouts with an ADA specialist, you don’t want to create a problem in the future by guessing or overestimating today.

How many parking spots do I need?

 

 

At Calvac Paving, we have ADA Expert(Certified Access Specialists) available. Our ADA Expertspecialists serve the San Jose area as well as the greater Bay Area.


Maintenance Mondays -Your Sealcoating Matters-

Calvac Paving Slurry Seal

Helpful Tips sign Sealcoating is an important process in the maintenance of your all too expensive parking lots.  We all know that the costs for paving repairs have increased.  This makes it all the more important to protect and preserve your asphalt surface.  Calvac Paving has been applying sealcoat for over 45 years, longer than most Bay Area Suppliers have been making asphalt based sealcoats.  Each successive generation of sealcoats has provided greater protection from premature wear, moisture intrusion and oxidation.  Even with these improvements we strongly recommend the addition of latex and sometimes sand to the existing asphalt sealcoats to extend the life expectancy of these applications.  It is also vital for you to have your contractor apply two coats of sealcoat to your property.  The first coat, with the added sand and latex, is the filler coat and allows placement of a second coat with added latex only or wear coat.
Preparation of the existing asphalt surface is a very important process in sealcoating your parking lot.  Calvac Paving will spend the time necessary to clean and prepare your asphalt to assure a durable and attractive product. We will remove all vegetation, and apply herbicide if appropriate.  We will use Power blowers, scrapers, wire brushes and brooms to thoroughly clean the existing asphalt.

IMG_3641

This preparation may also include Mobile Sweepers, water trucks or buggies and vacuum trucks.  We will burn, scrape and carefully clean the oil spots and apply an oil spot sealer with sand.  We will mask utility covers and other structures to protect against coverage.  We will apply hot rubberized or coldpour emulsion crackfiller as directed.
The consistency of the asphalt sealer is also very important to the durability of your sealcoat project.  Calvac Paving will never exceed the manufacturer’s recommendations for dilution.  This addition of water is necessary for the application and actually improves the bonding to the existing asphalt surface.  We feel the addition of latex and sand to the asphalt sealer extends the life of the sealer, and we include these admixtures in well over 90% of our sealcoat projects. By extendeding the life of your sealcoat surface with added latex, you reduce the number of times you will need to seal coat and stripe your lot as well as impose upon your tenants over the life of the asphalt.
The combination of effective barricading and traffic control with superior craftsmanship and products will provide you with the best result with the least impact upon you and your tenants.

before&afterslurryseal

 


Maintenance Monday: 10 Ways to Prepare Your Asphalt for Summer

Calvac Paving Bay Area Asphalt and Concrete Contractor

 

Whether it’s a roadway, a driveway or a parking lot, asphalt takes a pounding over the fall and winter months. The cooler temperatures and more frequent rains can take a toll on even the most robust and well-constructed asphalt pavements. To ensure maximum safety and durability for your asphalt and the people who travel and park on it, Calvac Paving presents ten ways to prepare your asphalt for summer!

 

1.  Take a Closer Look.

Asphalt is very durable and resilient, but there are a number of ways it can fail, so it’s a good idea to have a thorough walkthrough at least quarterly. You should check the condition of your asphalt more frequently in cases of unusually heavy or inclement weather, or if you notice indications of a problem like water flowing down the middle of your lot or roadway.

 

2.  Cracked-Up Asphalt isn’t Funny. 

Surface cracking often indicates that the subgrade beneath the asphalt is failing, this will also allow water penetration into the subgrade. In these cases, depending upon the severity, the affected problems such as potholes, alligatoring, or area(s) need to be removed and replaced.

 

3.  Paint it Black.

If your asphalt looks gray rather than black, has a pitted look or you notice deep cracks which may allow water to infiltrate to the subbase, it’s time to engage in crack filling and sealcoating, to help preserve and protect the asphalt and retard further damage. 

Note: Most unsealed asphalt has a rough and somewhat textured surface, because of the placement methodologies and the type of hot mix used. The larger the aggregate in the mix the stronger the pavement, but you give up the smooth appearance

The solution to this rough surface is twofold. First, an admixture of 2% latex per gallon of raw seal coat is added to both coats of material. secondly, adding one to four pounds of sand to the seal coat on the first coat will add necessary fine aggregate to fill the voids in the asphalt pavement. No sand is added to the second coat. This works to ensure a better looking, longer-wearing surface.

4.  Don’t Stand for It!

Standing water can be a symptom of subsurface issues with a section of your asphalt, usually caused by compaction failure in the subbase. Not only can standing water erode the surface as we’ve already discussed, but it can also undermine the integrity of other sections as the water is forced out of the depression and follows the drainage profile of the area in question.

 

5.  Rainbows Belong in the Sky, Not on Your Asphalt!

If you notice iridescent or rainbow-colored patches, these should be cleaned off as soon as possible. Oil and fuel spills can degrade the asphalt’s surface quickly, creating imperfections which over time can become full-fledged failures, reducing your asphalt’s performance and lifespan. 

 

6.  Clean it Up.

In addition to the fuel and oil spills mentioned above, it’s always a good idea to keep your asphalt clean and clear of debris such as garbage. Food products, in particular, should be cleaned up quickly, because these tend to have a relatively high acid content, e.g., ketchup, hot sauce, salad dressing, which then lingers on the surface, promoting deterioration of the asphalt. Besides, it just looks nicer!

 

7.  Root it Out.

If you have trip hazards such as uneven areas or raised roots, now is an excellent time to get them corrected. Trip hazards can be an expensive liability and can presage surface failure later depending upon the nature, type, and expression of the hazard. If possible, identifying and removing these hazards early can extend the life of your asphalt and help keep your insurance premiums down as well.

8. Traffic Control is Important.

Older and graying pavements make it significantly more difficult to see the traffic markings. This can lead to potential hazardous situations. Often the markings, arrows, crosswalks, stops and bars can become unrecognizable because of “ghosting”. This is the prior striping bleeding into view and confusing the drivers and pedestrians and leading to potential accidents. This condition is usually timely with the need to seal coat the pavement. Seal coat and restripe will solve this for years to come. This will also allow the property to be brought up to the current Building Code.

9.  Time is Not on Your Side.

By the time most people notice a problem with their paving, the damage could be far more extensive than even a detailed site walk can really pinpoint. Frequent examination and correcting areas which show indications of failure as soon as possible after they’re noted can help prevent costly, time-consuming, and unnecessary repairs.

 

10.  Call in the Professionals.

A paving job done poorly can often be worse than no repair at all. That’s why it’s worth your while to bring in pavement professionals with a solid track record of proven results. Calvac Paving has been serving the Bay Area since 1974, and we have the experience, resources and personnel to do the job right the first time, every time. Put our experience and cutting-edge construction technology and methods to work for your project by calling any of our Bay Area locations or clicking here to contact us!


Asphalt: The Most Recycled Material In America!

Recycling is important for our ongoing quality of life. It allows us to reclaim and reuse materials which would otherwise go to waste, clogging up landfills and contaminating our oceans. When most people think of recycling, they may think of cans, bottles, paper or even old computers. But surprisingly, the most recycled material in America is literally right under our feet: asphalt!

Unlike many recyclables, which may have limitations on specific types which can be recycled, any asphalt pavement can be 100% recycled. The American Asphalt Association recently released 2016 data which stated about 79 million tons of asphalt was reclaimed and reused in roadway mix designs and other activities, such as reprocessing into a recycled aggregate base course for use beneath the roadways themselves. In addition, nearly 1.8 million tons of waste and byproduct material from other industries were incorporated into asphaltic concrete mix designs during 2016.

We’ve previously discussed the possible use of plastic bottles and even cigarette butts as elements of asphalt designs which are being explored. By reclaiming these materials into asphalt, it increases their recyclability as part of the mix and helps reduce their impact in landfills. The APA says recycling asphalt saves an estimated 14,664 Olympic-sized swimming pools’ worth of landfill space each year. By adding other recyclable and waste materials to asphalt, this impact will only become greater in years to come.

Recycling asphalt isn’t just good for saving landfill space. It also reduces the environmental impact of quarrying and processing the aggregates and bituminous binders used in the asphalt production process.

Asphalt can be recycled in a number of ways. One of the most popular, and the way which reclaims 100% of the asphalt involved, is to pass chunks of asphalt through a special recycling assembly which raises the temperature to 300℉. Once the asphalt has been processed using this method, it can be laid down on roadways using existing paving technologies and techniques. In this form, it is known as Recycled Asphalt Pavement, or RAP.

Another method of asphalt recycling involves crushing asphalt at a hot mix plant and using the resulting RAP as an additive for “virgin” hot mix. This type of recycling allows for over 30% of the final product to consist of recycled asphalt. By comparison, some brands of paper cups may use only 10-25% post-consumer content, highlighting the recyclable nature of asphalt.

A third way which also reclaims 100% asphalt is to crush the asphalt down into gradations suitable for road base. Rutgers University conducted a study in which RAP was compared to conventional aggregate subbase for use in roadways. The study showed the RAP had more elasticity and stiffness (are you sure they said this, seems contradictory) than the aggregate subbase when the two materials were laid using identical placement methodology. This means RAP is actually stronger, more resilient and better for the environment than regular aggregate road base, while delivering comparable performance as a base material.

If the environmental benefits aren’t impressive enough, consider the potential savings for recycling. That’s right, recycling asphalt costs less than new paving! One estimate places potential savings at a national average of around 55%, or between 30-80%, over virgin hot mix.

It’s up to all of us to do our part to make our world a better, cleaner and healthier place, from the global level to our own homes. At Calvac Paving, we are always on the lookout for ways to perform our work more efficiently and cost-effectively while also remaining environmentally responsible. This means keeping a close watch on new technologies, methods and California State standards which would allow us to deliver comparable or superior results with less environmental impact and greater ROI for our clients. To learn more about Calvac Paving’s commitment to the environment, or to put the four decades of experience we’ve accrued to work for you, please contact us at (408) 225-7700 or www.calvacpaving.com

 


Maintenance Monday – Joints In Concrete Slabs

calvac paving discusses joints in concrete slabs

Concrete is not a ductile material-it doesn’t stretch or bend without breaking. That’s both its greatest strength and greatest weakness. Its hardness and high compressive strength is why we use so much of it in construction. But concrete does move-it shrinks, it expands, and different parts of a building move in different ways. This is where joints come into play.

Although many building elements are designed and built with joints, including walls and foundations, we’ll limit this discussion to joints in concrete slabs. Here’s an overview of the types of joints, their function, and tips for locating and installing joints.

Concrete Joint Information

Calvac Paving discusses Concrete Joint Information

Different joints in concrete slabs all have the same bottom-line purpose of preventing cracks

 

As concrete moves, if it is tied to another structure or even to itself, we get what’s called restraint, which causes tensile forces and invariably leads to cracking. Restraint simply means that the concrete element (whether it’s a slab or a wall or a foundation) is not being allowed to freely shrink as it dries or to expand and contract with temperature changes or to settle a bit into the subgrade. Joints allow one concrete element to move independently of other parts of the building or structure. Joints also let concrete shrink as it dries-preventing what’s called internal restraint. Internal restraint is created when one part of a slab shrinks more than another, or shrinks in a different direction. Think how bad you feel when part of you wants to do one thing and another part wants to do something else! Concrete feels the same way.

If you have a question for Calvac Paving, please contact us at

Calvac Paving
2645 Pacer Ln
San Jose, CA 95111
408-225-7700

sales@calvacpaving.com

 


Asphalt Crack Repair

Asphalt Repair

One of the processes that paving contractors can perform in these conditions of rain and clear skies is crackfilling. It takes just a day of good weather to allow us to come in and prepare the cracks with the installation of the crackfiller the following day if necessary. Here is some information concerning this service.

CONDITION:

Linear cracking in your asphalt surface. Aged and oxidized asphalt that has intermittent cracking. These cracks are typically wide spread throughout the property and not concentrated in one area nor interlocking.
If there are alligatored areas (interconnecting cracks) then these areas should be repaired rather than crackfilled. These problems are exacerbated by the intrusion of water which will penetrate to the subgrade and accelerate cracking and base failure caused by shrink/swell of the subgrade.

Latest Paving Job Calvac Paving

CAUSE:

Causes of this linear cracking could be a less than satisfactory base course on top of a moisture sensitive subgrade causing swell and shrinkage in that subgrade. This movement reflects through the base course and the up through asphalt surface. The infiltration of moisture through this cracked and oxidized (dried out) asphalt accelerates the damage.
Additional causes would be ground slippage, expansion and contraction due to heat and cold cycles, shrink/swell of the subgrade, the advanced age and oxidization of the asphalt surface.

CORRECTION:

Cracks that are 1/4” -3/8” can be filled with a cold pour asphalt emulsion crackfiller. Cracks that are 3/8” – 3/4” will require the use of a hot rubberized crackfiller. Cracks larger than 3/4” should be corrected with hotmix asphalt, by filling the cracks with hotmix asphalt and covering with hot pour crackfiller and better yet is to follow up with a Petromat overlay of the area.
With either application the cracks will have the existing vegetation removed and then the crack will be blown out with high pressure air and high heat. If necessary we can apply a spray sterilant to the existing vegetation prior to removal.
If we apply cold pour crackfiller, then that material is poured into the crack to bridge the opening and create a flexible filler that is then struck with a specialized squeegee to force the material deeper into the crack and to localize the coverage of the material into a thin strip at each side of the crack.
If the cracks require hot rubberized crackfiller, then that material is heated to 350°+ and the material is forced into the crack and struck flush with the surface.

If your property is in need of a asphalt/concrete repair, Calvac Paving is standing by to assist!

Calvac Paving
2645 Pacer Ln
San Jose, CA 95111
408-225-7700