Topic: Blog

Five Reasons the Best Time to Maintain Your Asphalt Is NOW!

The last 18 months have been rife with uncertainty and riddled with worry for nearly everyone. With businesses closing temporarily or permanently, the Bay Area’s paving situation has never been as dire as it is now. The fact is, if your parking lot, driveway, and other paving problems aren’t corrected early, they’ll get worse and more expensive to fix later. Here are five reasons the best time to maintain your asphalt is NOW!

 

1. Fluctuating Oil Prices

The price of oil impacts everything, perhaps especially in the construction industry. Asphalt and concrete batching and production processes are uniquely affected by the cost of oil. In July 2020, the cost of asphalt tumbled to a low not seen since March of 2017. One year later, the price has increased by nearly 50%, spurred on by rising oil prices and a concurrent rise in the cost of refining, processing, and batching. With prices going up, now is the best time to lock in current rates for asphalt and concrete before the cost jumps even higher.

 2. Curb Appeal

How can you tell the difference between a closed business and a business that’s open and ready to take care of its customers? The truth is your customers can’t, especially if they’re driving by on the street. Cracked, faded, potholed parking lots with worn-out striping are unattractive to the eye and send an unflattering message to potential clientele. By repairing your parking lot, accessways, and other curb and drive installations, you clearly communicate that you’re open for business, ready to get to work and able to assist your customers with all their needs.

 3. Safety

Did you know that cracked or potholed asphalt, offset sidewalk slabs, and other defects and damaged portions can be a safety hazard? It’s true! If a customer trips and falls because of poorly cared-for paving, your business may be liable for any injuries they sustain. Such hazards can also impede disability access to your business and maybe an ADA violation with a fine of up to $75,000 for the first infraction and $150,000 for each subsequent violation. When you add up the stiff financial and reputation costs of noncompliance and the potential for injury to your staff, customers, and the general public, having your parking lot and sidewalks repaired looks like a pretty good bargain.

 

4. Weatherproofing

When cracks form in asphalt paving, it allows water to infiltrate the subbase. A small trickle of water isn’t a big deal, though, right? Unfortunately, no. As water seeps into the pavement, it wears and washes away the surrounding material and pools within the matrix, allowing plant seeds to take root and start to grow. During colder weather, it may freeze and expand. These erosive processes accelerate cracking and pothole formation as well as undermining the structural integrity and flexibility of the overlying surface. At a certain point, the paving will be beyond repair and will have to be completely removed and redone to work properly. A well-maintained parking lot will perform and look better for years to come.

 5. Increase and Safeguard Your Property Value

Faded, cracked, or faulty paving can be expensive in more ways than you think. It can also drag down the property value, especially if you’re considering selling in the near future. If your paving looks good, it will also perform well for years to come, making the property a better investment for anyone who might end up buying.

 

All in all, maintaining your asphalt paving is a smart investment with a lot of benefits and virtually no downside over time. Whether you need a simple sealcoat and restriping, a spot patch and repair on a faulty section, or a complete tear-out and rebuild of your asphalt and concrete paving, Calvac Paving is here to help with proven, durable results that give you, your tenants, and their customers the great performance and appearance they expect and deserve. For all your Bay Area paving needs and a job that’s done right the first time, every time, click here to contact Calvac Paving today!

 


5 Major Asphalt Advances to Watch in 2022 From Calvac Paving

Calvac Paving Bay Area Asphalt and Concrete Contractor

From the highway to the driveway, asphalt paving gets you where you need to go. Humanity has been using asphalt and bitumen for projects as diverse as waterproofing, shipbuilding, and road paving for millennia, and it has continued to prove its utility at every turn. In 2022, Calvac Paving is excited about some new advances in paving technology that could be game-changers for drivers, owners, stakeholders, and local, state, and federal authorities and agencies alike. These are the five major asphalt advances you’ll want to watch in 2022, brought to you by your friends at Calvac Paving!

 

Alternative paving materials

 

From cigarette butts to recycled plastic to rubber-modified asphalt (RMA), scientists worldwide are exploring the application of old materials, used in new ways to enhance the strength, longevity, sustainability, recyclability, and resilience of asphalt paving. These alternative paving materials may help combat issues like the “urban heat island” effect, keeping asphalt-paved surfaces cooler and allowing them to trap less heat year-round. They also offer new ways to reduce waste, reuse materials, and recycle “junk” materials that are typically discarded, helping break the waste chain and creating a healthier environment by keeping these materials out of landfills, waterways, and oceans.

 

Smart pavement

 

Technology may soon make your morning commute or your summer trips safer and easier, with fewer bumps and less noise! Integrated sensors that report everything from traffic conditions to overall roadway and pavement health are being tested around the globe. Nanoparticle-based noise- and vibration-damping adhesive binders for asphalt mixes are under investigation as a potential solution to problems such as roadway chipping and pitting. And roadways that charge electric vehicles as they drive using wireless recharging technologies are in active use or the planning stages from Sweden to Michigan to Norway, solving one of the EV’s biggest hurdles while also making paving even more environmentally friendly!

 

Asphalt continues its reign as the world’s most recycled material.

 

Roughly 100 million tons of asphalt pavement mix are produced each year globally. Of that amount, an estimated 95% is reclaimed, reused, recycled, or repurposed, making asphalt one of the planet’s most readily recyclable materials. Perhaps most importantly, recycling asphalt helps keep costs lower and reduces reliance on foreign oil to create the bitumen binder that gives asphalt paving its flexibility. With all these factors going for asphalt, it’s reasonable to expect even bigger pushes to maximize asphalt recycling up to a full 100% in 2022 and beyond.

 

Inflation and rising oil prices

 

Between the war in Ukraine and US embargos on Russian goods, including oil, the continuing effects of the COVID-19 pandemic on shipping and trade, and a period of high inflation, prices are only getting higher for just about everything—and asphalt pavement is no exception. Recycling and the use of alternative paving materials will help offset this increase greatly, but paving contractors and stakeholders can still expect to see reduced profits and higher up-front costs, at least through the summer.

 

Striping

 

Some of the biggest advances and hottest trends in paving technology don’t really have to do with the pavement itself—but the paint! Striping is a perennial headache for entities from the federal government all the way down to small business owners trying to keep their parking stalls and handicapped spaces ADA compliant, but new formulas and application methodologies appear poised to change that in 2022. New advances in striping paint include more eco-friendly options, nanotechnology and microfibers for increased durability and longer utility life, and additives and refined formulas for heightened visibility. Autonomous, self-piloting robotic paint sprayers which deploy striping more uniformly, more accurately, and with a greater level of precision than humans are capable of are making a big impression across the industry.

 

At Calvac Paving, we’re excited about (most of) what 2022 has in store for the paving industry, as well as how new advances and technologies are going to change both the paving industry and the face of our world. Since 1974, we’ve been committed to making the use of concrete and asphalt paving in construction as efficient, cost-effective, and environmentally friendly as possible. Because of this commitment to a greener, cleaner planet for all, and better-forming pavement applications for our customers and stakeholders, we’re looking forward to seeing the next big advances and putting them to work!

When you need a Bay Area paving contractor with an unparalleled safety record who goes above and beyond to deliver consistently outstanding results, click here to contact Calvac Paving. Let us show you what sets Calvac Paving apart from other paving contractors and why we’re the paving company the Bay Area trusts from the driveway to the highway and home again!

 

 


Maintenance Monday – How Portland Cement is Made

Cement Plant For Calvac Pavings Blog

Portland cement is the basic ingredient of concrete. Concrete is formed when portland cement creates a paste with water that binds with sand and rock to harden.

Cement is manufactured through a closely controlled chemical combination of calcium, silicon, aluminum, iron and other ingredients. Common materials used to manufacture cement include limestone, shells, and chalk or marl combined with shale, clay, slate, blast furnace slag, silica sand, and iron ore. These ingredients, when heated at high temperatures form a rock-like substance that is ground into the fine powder that we commonly think of as cement.

The most common way to manufacture portland cement is through a dry method. The first step is to quarry the principal raw materials, mainly limestone, clay, and other materials. After quarrying the rock is crushed. This involves several stages. The first crushing reduces the rock to a maximum size of about 6 inches. The rock then goes to secondary crushers or hammer mills for reduction to about 3 inches or smaller.

The crushed rock is combined with other ingredients such as iron ore or fly ash and ground, mixed, and fed to a cement kiln. The cement kiln heats all the ingredients to about 2,700 degrees Fahrenheit in huge cylindrical steel rotary kilns lined with special firebrick. Kilns are frequently as much as 12 feet in diameter—large enough to accommodate an automobile and longer in many instances than the height of a 40-story building. The large kilns are mounted with the axis inclined slightly from the horizontal.

Old cement dispenser company

The finely ground raw material or the slurry is fed into the higher end. At the lower end is a roaring blast of flame, produced by precisely controlled burning of powdered coal, oil, alternative fuels, or gas under forced draft.

As the material moves through the kiln, certain elements are driven off in the form of gases. The remaining elements unite to form a new substance called clinker. Clinker comes out of the kiln as grey balls, about the size of marbles.

Clinker is discharged red-hot from the lower end of the kiln and generally is brought down to handling temperature in various types of coolers. The heated air from the coolers is returned to the kilns, a process that saves fuel and increases burning efficiency.

After the clinker is cooled, cement plants grind it and mix it with small amounts of gypsum and limestone. Cement is so fine that 1 pound of cement contains 150 billion grains.  The cement is now ready for transport to ready-mix concrete companies to be used in a variety of construction projects.

Although the dry process is the most modern and popular way to manufacture cement, some kilns in the United States use a wet process. The two processes are essentially alike except in the wet process, the raw materials are ground with water before being fed into the kiln.

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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!


8 Signs Your Asphalt May Be Failing

Asphalt is a very versatile and durable paving material. Its resilience and flexibility make it an ideal surface for everything from eight-lane superhighways to driveways to parking lots. However, asphalt does require care and maintenance to function at peak performance, and it can fail for a number of reasons. If you see any of these warning signs of failing asphalt, quick action can save you a lot of time, money, and hassle. Here are eight signs your asphalt may be failing—and what you can do to fix them!

 

1.  Alligatoring

Alligatoring is called that because of its appearance: interconnected cracks that look like alligator skin. It is an indication of load-related deterioration which could be caused by a weakened or improperly compacted subbase material, excessive traffic loading, inadequate pavement thickness, or a combination of these factors.

 

2.  Edge Cracks

Edge cracks are found within 1-2 feet of the outer edge of the asphalt surface, running longitudinally, or roughly parallel to the outer edge. These cracks are caused by improper support of the paving surface at the margins.

 

3.  Reflective Cracks

Reflective cracks most typically form in joints or areas of concrete or asphalt paving which have been previously repaired, such as with crack sealing or where a temporary corrective overlay has been placed to relieve stress on deteriorated paving. These cracks form because of continuing movement of the old pavement due to continuing traffic load.

 

4.  Slippage Cracks

Slippage cracks are easily identifiable because of their crescent shape. They occur either due to poorly bonded pavement layers or an asphalt mix design which is insufficient to the demands of the traffic patterns. These cracks appear because of forces applied by turning or braking vehicles, which cause the pavement to move slightly at first but with accelerating damage to the surface the longer the underlying cause goes uncorrected.

 

5.  Rutting and Depressions

Rutting is caused by weakness of the subgrade or base soil layers, instability of an asphalt mix, insufficient pavement thickness, or poor compaction. Rutting is a linear, surface depression of the wheel path caused by deformation or consolidation of any of the pavement layers or subgrade. Depressions, also known as birdbaths, are localized areas of pavement surface failure caused by poor initial construction techniques that undermine the asphalt over time. These may occur on their own or in conjunction with other failure indicators. If left unchecked, depressions can become potholes (see #8).

 

6.  Asphalt Patch Failure

These failures are easy to spot because they’re very localized to the area where a patch was placed, and characterized by unevenness, deflection or stress cracking along the perimeter of the patch. They are caused by either not fully removing the damaged area to be patched, or not allowing a minimum of one extra foot around the perimeter of the patch area to ensure the patch is bonding to an uncompromised surface. The rate of patch deterioration is influenced by materials selection, compaction, and the quality of the surrounding pavement as well as the underlying subbase. While the latter is not typically visible, adding one additional foot around the patch can help patches last longer and function better under load.

 

7.  Raveling

Raveling is caused when the aggregate particles in the asphalt cement wear away under traffic forces. This condition suggests either that a poor-quality mixture was used or the asphalt surface has hardened enough to no longer be supple and flexible.

 

8.   Potholes

These bowl-shaped holes are caused by localized disintegration of the pavement surface. Potholes are usually the result of another type of distress that has not been properly addressed. Segregation, failed patches and cracks can all lead to a pothole over time. Weak spots and localized areas of improper or insufficient compaction in the subgrade or subbase, or poor asphalt mix designs, can accelerate degradation of the pavement surface and the formation of potholes.

 

When you notice indications of paving failure, bring in an experienced paving contractor as soon as possible to restore the surface and minimize downtime, expense and the risk of further, more severe failure in the future. Calvac Paving has been proudly serving the Bay Area and beyond for over 45 years, and we’d like to put that experience to work for your next paving repair or new construction project. For more information, or to learn more about how Calvac Paving can deliver the results you need and want, call any of our Bay Area offices or click here to contact us today!


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

 


New Medical Building Parking Lot

Calvac Paving’s commitment to service means that we often have projects that present unique challenges. For a medical center in Menlo Park, there were several problems that had to be overcome. First, the base below the asphalt had become unstable, leading to depressions and potholes in the surface. Due to these conditions the existing asphalt had to be removed, the baserock graded and compacted. Second, the existing asphalt had to be off hauled and new pavement placed over the recompacted baserock. Finally, because it is an active office, we had to complete the removal, replacement and striping in a single Saturday.

When we first arrived, the parking area was riddled with potholes and puddles from the destabilized base. The existing striping and stall design of the parking lot was several years out of step with current ADAS and CBC standards for access. We then scheduled the off haul of recycle and import of hotmix asphalt tonnage and we mobilized the equipment and manpower necessary to complete the job, as well as staging the striping crew. Since we had a very tight window and no margin for error, we knew this had to be done efficiently and correctly the first time, with no delays. After blocking off the area so that we could work safely, we began grinding out the existing asphalt using a specialized milling machine. This pulverized the existing asphalt so that we could haul it to a local recycling plant, while exposing the existing baserock surface. Once that was completed, we graded and compacted the baserock so that Calvac Paving could create a stable, uniform surface that would create the necessary drainage and eliminate the puddles. This process, known as “grading,” is key to establishing a surface safe for vehicles and pedestrians while permitting stormwater drainage, which helps prevent subgrade destabilization by not allowing water to collect and seep through the asphalt.

Once the grade had been established and the baserock compacted to comply with industry standards and project specifications, we placed fresh hotmix asphalt in two 2” layers, or “lifts.” Compacting the asphalt in lifts as it was placed, created an end product that is more durable, less prone to cracking, potholing and other problems seen with asphalt paving. Once the second lift was placed, and we fog sealed the surface, we then had to layout and stripe the parking lot up to current ADAS and California building code requirements for correct access to the building and parking areas.

The result was a very smooth and puddle free, pedestrian, parking and driving surface that is far more stable than the previous paving, as well as meeting the latest standards. At the end of the project, we had removed and replaced more than 150 tons of hotmix asphalt in a single day, which was a quick turnaround for this volume of material and the job specific constraints.

Calvac Paving has been serving the Bay Area for over 45 years, from road rehabilitation projects in Los Altos Hills to this medical center parking lot overhaul in Menlo Park, and we have constructed, repaired or remediated thousands of properties. Each project requires a slightly different approach, due to project requirements, schedules, access concerns and other factors. We pride ourselves as the Bay Area’s solution to those supposedly “challenging” jobs, combining our reputation for safety and efficiency with the attitude that there’s no reason to consider a job “challenging” with the right safety, tools, training and equipment.

We also offer an industry-leading three-year warranty on the finished product to our qualifying clients as proof that we stand behind our product and the workmanship that goes into it. We are committed to providing our clients and stakeholders the best and most efficient results in the business, while making sure that the product that we leave behind is one we can look back at with pride. For more information about how Calvac Paving can help with your job, from a major roadway reconstruction to building an ADA-compliant access point to restriping a parking lot, we invite you to call us at:

(408) 225 – 7700

(650) 694 – 7944

(831) 375 – 7944

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Some things in life shouldn’t be left to chance, and the surfaces where you, your family and your clients drive and walk on a daily basis are good examples. When you want the best, done right the first time, every time and on time, you want Calvac Paving, and we want to help!


Maintenance Monday: When Was Asphalt Paving Invented

picture of asphalt by calvac paving

At Calvac Paving, we think the history and evolution of paving and construction materials over time is just as interesting and important as using them properly to deliver great, durable results for the projects we work on. For this week’s Maintenance Monday installment, we’re going to take a look at the surprising and fascinating history of asphalt and answer a few questions we get a lot from clients and the general public. You might even learn new facts to stump your friends or help your trivia team crush the competition, courtesy of your friends at Calvac Paving!

 

When Was Asphalt Invented?

 

The “active” ingredient in asphalt is tar, also called pitch and technically known as bitumen. It is a naturally occurring petroleum byproduct that is formed from the decomposition of buried plants that were ancient when the dinosaurs rose to ascendancy on the planet. It is often found in pitch lakes and oil sands. It is also created as a byproduct of petroleum distillation, which today is the most popular source of bitumen due to global fossil fuel consumption.

One of the most famous natural sources of bitumen is California’s very own La Brea Tar Pits, which also happens to be one of the most notorious and productive Ice Age fossil concentrations in America. This is because water accumulating and floating on the surface of the pits attracted prehistoric animals to drink from it—trapping them in the hot tar and preserving their remains!

The earliest known references to the use of bitumen as a building material date all the way back to ancient Mesopotamia. Bitumen was used to waterproof temple roofs, ritual baths, and rainwater collection vessels, basically serving as an ancient precursor to silicone caulking. The Phoenicians used pitch to protect the hulls of their ships from the ravages of saltwater, weather, wind, and waves, which in turn helped rank them among the world’s most skilled and feared navies of the day. There is a school of thought that suggests the formula for the legendary “Greek fire,” which could burn on water and was primarily developed as a counteroffensive measure against the Phoenicians and other seafaring foes, may have incorporated bitumen in some way, though this cannot be factually substantiated since the actual process for producing this fearsome weapon has been lost to the ages. In Egypt, bitumen was employed as an adhesive for the funerary wrappings of royalty to protect both the earthly bodies and the treasures bound within the linen bandages which formed the shroud.

To the best of our knowledge, Ancient Babylon has the best claim to fame for the first use of asphalt as a paving material, somewhere around 625BCE. 

From Babylon and Carthage, the idea caught on with both the Greeks and the Romans. In fact, the word “asphalt” derives from a Greek word, “asphaltos,” meaning “secure.” The Romans used this new Babylonian technology to create smoother, more efficient roads to move goods, supplies, and, naturally, military forces throughout the Empire.

The first use of asphalt as pavement in modern history appears to date to the 1700s, when an Englishman named John Metcalf began laying roads using asphalt around England. A Scot, Thomas Telforld, took up the idea and brought it to Scotland, where it was later perfected by one John Loudon Macadam. Macadam used a combination of crushed rock and bitumen to create his asphalt roads, giving rise to the names “tarmacadam,” “macadam” and “tarmac,” all names which are still in common use on the Continent, and to a lesser extent in the United States, today.

 

Asphalt in America

The first recorded asphalt roads in the United States were laid in Newark, New Jersey and on Pennsylvania Avenue in Washington, DC by a Belgian chemist, Edmund DeSmedt, in 1870. This was also the year the first hot mix production operation in the United States began. Curiously, the first patent for asphaltic concrete was not filed until 1871! Another patent in 1900 referenced “bitulithic” concrete, a portmanteau term of “bitumen” and “lithos,” the Greek word for “stone,” which set the foundational template for nearly all asphalt mix designs used in America up to the present day.

As early as 1907, the rise of automobiles as a primary transportation method and the increasing demand for gasoline to fuel them had made man-derived asphalt the most popular source of bitumen. In a magnificent twist of ingenuity and synchronicity, the very thing that made cars run also provided the materials on which they could drive!

 

Asphalt Today

Today, asphalt or asphaltic concrete, as it is technically known, is by far the most popular paving material for everything from parking lots to interstate highways. It is also used in roofing materials such as asphalt shingles. Raw hot mix can also be applied to the surface of a roof, creating a light, strong, waterproof surface.

Natural asphalt is rarely used these days, partially because asphalt derived as a byproduct of petroleum production is so plentiful and relatively cheap compared to the expense and effort required to distill asphalt into a usable purified form. 

Another reason natural asphalt sources go largely untapped is because many of them, like the La Brea Tar Pits, are protected by local, state, and federal laws for their paleontological and cultural value. 

Fossil plants, animals, insects, and human artifacts from Native American tribes in these areas have all been found, making their ongoing conservation and preservation a major point of interest to nature and environmental groups, Native American tribes, and government agencies alike.

Finally, asphalt is one of the most recycled substances on earth. An estimated 89.2 MILLION tons (178.4 billion pounds/81.09 billion kilograms) of asphalt were reclaimed and recycled into new mixes in 2019 in America alone according to the National Asphalt Paving Association. This means that overall, asphalt is very environmentally friendly and is not considered an air pollutant by the EPA, even though the fumes from fresh asphalt can be a little overwhelming if you’re not used to them.

So the next time you’re driving down the highway or pulling into your own driveway, you might take a moment and spare a thought for the fact you’re driving on the results of an idea older than recorded history! 

And of course, for all your concrete and asphalt paving needs, click here to contact Calvac Paving and get the job done right the first time, every time!  


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.

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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

 


The Lost Art Of Concrete

Cement Contractors

The saying “They don’t build ‘em like they used to” is literal truth in the concrete industry. For decades, modern science has struggled to work out how ancient societies such as the Romans were able to create buildings, monuments and roadways which are still visible and even in use today, when the average lifespan of modern concrete tends to be far more modest. Now, a team of scientists from the University of Utah believes they may have found the surprising answer to this centuries-old mystery.

Modern concrete uses Portland cement as its base, which is a fine powder created from lime, chalk, sandstone, iron and other materials and then combined with aggregates of varying sizes. However, the Romans used a type of cement created from the ash of certain volcanoes. These volcanoes’ emissions contained a rare combination of mineral elements which only occurs naturally in very specific areas with particular geological profiles. What’s most surprising is that the minerals which make Roman cement different from Portland cement appear to react to seawater, which encourages the crystalline structure of the minerals to continue growing. This actually makes the concrete self-healing and impedes cracking, a feat modern science is still trying to replicate.

This discovery of how Roman concrete was made is important because it could lead to greener and more eco-friendly concrete production and paving technologies, as well as structures with higher strength, structural integrity and longevity under adverse conditions than modern concrete allows for. In addition, Roman concrete did not use reinforcing steel such as a wire mesh mat or rebar, both of which Portland cement will corrode and degrade over time. This may lead to significant cost reductions for new construction on structures like bridges, building footings and other applications.

However, the research team warns it’s too early to get too excited about Roman concrete. First, Roman concrete relies on very specific minerals, namely tobermorite and phillipsite, being present in certain quantities. The researchers say the composition of Roman concrete was largely a matter of luck and being in the right place, at the right time, with access to the right materials. Second, we don’t yet know exactly how the Romans made their cement or what the process was for mixing it with aggregate and placing it. This by itself may leave us several years, or even decades, away from being able to use Roman concrete effectively.

Despite these hurdles, the concepts behind Roman concrete and other green discoveries from the ancient world are constantly being studied, evaluated and applied to our modern understanding of how to build things that last. At Calvac Paving, we’ve been serving the Bay Area for over 45 years in the most environmentally friendly, safe and expedient way possible. We’re always on the lookout for new developments, technologies and ideas which will let us do our jobs more effectively, with less impact on the world we all share. To learn more about our commitment to the environment, or how Calvac Paving can help you with your next project, contact us at:

Calvac Paving
2645 Pacer Ln
San Jose, CA 95111
(408) 837-9021