Posts By: Calvac Paving
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
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
2645 Pacer Ln
San Jose, CA 95111
Calvac Paving was proud to be able to serve the city of Los Altos, California by replacing a common private road within the community. The roadway needed repair for durability, safety and aesthetic reasons, giving Calvac Paving the opportunity to once again demonstrate the quality and attention to detail of our work.
This project required some delicate handling because, as a private road in a residential area, Calvac Paving had to be mindful of residents’ access needs as well as the possibility of fires or other emergencies. It also necessitated using a special process that allowed for minimum road closure time and maximum performance. We created a short video to show the highlights of the paving process, from top to bottom.
The process Calvac Paving decided to use was a “petromat” overlay on top of the existing roadway. To do this, the failed areas were prepatched using full depth hot mix asphalt. Once this was done, the existing utility boxes in the roadway were raised up, so as to secure them against further failures in the subgrade or roadway itself. An asphalt binder and paving fabric were installed next, allowing the existing road surface to bond properly to the hotmix upon placement. A 2” lift of hotmix was placed using a self-propelled paver, and then the lift was compacted to produce a smooth, level road surface.
The finished product is much nicer-looking, offers more flexibility and durability, and didn’t require as much disruption of local traffic patterns as more traditional repair and rehabilitation projects. Calvac Paving specializes in these kinds of jobs, where tight traffic constraints and the need for access make conventional processes difficult or impossible. In this particular case, we left the property owners with a smoother, more aesthetically pleasing, better-driving roadway.
Calvac Paving has been serving the Bay Area since 1974, providing the highest-quality paving, concrete and earthwork solutions for residential, commercial, transportation and public applications. From annual budgeted concrete repairs, asphalt paving and seal coat to a complete new roadway build and striping services, Calvac Paving has the equipment, knowledge and experience to deliver excellent quality at competitive prices. We approach every job with a can-do attitude and consider carefully how to proceed to obtain the best balance of cost effectiveness, performance and safety.
Because our President, Jim Adam, carries CASp certification, Calvac Paving is also an ADA-certified company. This means we are continuously keeping abreast of new developments and adaptations to ADA regulatory requirements and standards. Carrying this prestigious and important certification allows us to ensure every project we undertake is in full compliance with ADA Standards as well as the California Building Code, which in some cases are even more stringent.
In addition to our certifications and awards, Calvac Paving offers a three-year warranty to qualifying customers, three times the industry standard. We stand behind every job we do with strict quality and performance standards, because we want our clients to have peace of mind that the work they get from Calvac Paving will be the best anyone, anywhere can deliver. We hold our work to the highest possible standards for materials, workmanship and durability, Calvac Paving can take pride in giving our clients/Stakeholders a finished product they can trust.
Calvac Paving is proud to have served the Bay Area as long as we have, and we will continue to do so in 2016 and beyond. Whether we’re fixing a private roadway in Los Altos or working on a major airport runway renovation, striping a parking lot or building an access ramp to the exacting tolerances of ADAS and CBC requirements, we are passionate about our work and proud of the final result. To learn more about how Calvac Paving can help you with your next construction project, we invite you to call our offices at the following numbers:
(408) 225 – 7700
(650) 694 – 7944
(831) 375 – 7944
You can also contact us by clicking here if you’d prefer to email. For top quality, on-schedule and on-budget, don’t gamble with the results. Call Calvac Paving and get the best right from the start.
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.
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.
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.
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!
2645 Pacer Ln
San Jose, CA 95111
At Calvac Paving, we support technologies and construction methodologies that offer a more environmentally sound and sustainable way of creating the things we as human beings have come to rely on. From asphaltic concrete recycling to innovations such as self-healing concrete, we are always on the lookout for trends and techniques that change how we operate for a greener, healthier planet. This is why we are so excited about the possibility of roads that actually recharge electric cars as they drive! These specially designed roadways will reduce pollution, increase the performance and range of electric cars to unheard-of levels, and reduce or entirely eliminate the need for charging stations.
In the UK, this seeming science fiction is becoming science fact, as the government moves to experiment with charging roads. Operating on the same principle as a wireless phone charger, the roads will charge cars through magnetic induction resonance. Cables implanted in the material of the roadway generate a specialized electromagnetic field that the car can convert into usable energy. The roads will also include communications equipment attuned to the unique energy signature of an electric car, alerting the road that an electric vehicle is present and to initiate the power generation process. This will allow properly equipped electric vehicles to recharge on the go, without needing to stop for extended periods to recharge, one of the biggest stumbling blocks cited in the adoption of electric vehicles thus far.
The roads the UK are experimenting with will be restricted for the time being, ensuring that regular vehicles do not impede the testing process. The government is committing 500 million pounds, or roughly $779 million, to these experimental roads over a five-year span. This technology is already in use in South Korea, powering rail systems with ranges of up to 15 miles, and will be combined with an added initiative to provide charging stations every 20 miles in the UK. The combination of options for drivers will help eliminate so-called “range anxiety,” which one advocate described as a combination of running low on gas and having one’s cell phone be low on battery simultaneously.
Magnetic induction resonance works in much the same way as a powerful operatic voice can shatter crystal. When the voice and the crystal reach a similar resonance, the molecules in the crystal begin to vibrate rapidly and cause it finally to break. Instead of shattering or rupturing the battery, however, the cables the charging roads utilize will create a harmonic resonance within the battery that allows it to transform the signal from the roadway into usable power.
Because many roadways contain metal in addition to the native subgrade, road base and asphalt in the form of rebar, wire-mesh matting and metallic joints between road sections, the cables can use this metal as a part of the transmission system for the power. The metal components of the electric car can be employed as a receiver, directing the transmitted energy to the battery without the driver needing to stop, handle any charging devices or worry about whether or not the car will make it to the next charging station.
Major car production companies such as Audi are leading the research into this technology, which they believe will relegate internal-combustion vehicles to the status of horse and buggy. By working together to create a standardized plug-in system for use in garages, parking structures and ultimately at-home use, these car manufacturers believe they can make charging stations easier to find and thus make electric cars more attractive. The idea of “switching stations,” where a person can simply replace a drained battery with a fresh one and continue on, and the increased range of electric cars to around 250-300 miles per full charge depending on the type of car and battery size, will help expedite this process.
While paved roads are still very much a part of the future landscape, what drives over those roads and what lies beneath them may soon play a more crucial role than ever in our environmental integrity and ability to move people and cargo. Calvac Paving will be watching the trials in the UK with a great deal of interest, because we want to see if this technology truly is feasible and what the implications will be for the paving industry. If everything pans out as the equations and scientists claim, this could be a major breakthrough and a huge tectonic shift in how things are designed in both construction and automotive industries, as well as manufacturing and transportation as a whole. We think that’s a pretty big win, and look forward to this technology here at home!
Maintenance Mondays: This project was for a Medical Building. This required the crew from Calvac Paving to work on a Sunday to minimize disruption. The bulk of the drive lanes were damaged to the extent that we had to remove and replace approximately 45% of the drive lanes. The crew completed approximately 260 tons of removal and replaced with 260 tons of hotmix asphalt. All of the removed asphalt was hauled to a recycle plant. Our crews were completed and out of our yard and on their way home by 6:30pm.
Calvac Paving – Top Quality. On Schedule. On Budget.
Calvac Paving, a San Jose based Asphalt and Concrete maintenance and construction Contractor is looking for Equipment Operators, Laborers and Skilled Workers. We are looking for full time workers and experience in Asphalt and Concrete construction is a plus.
Applications must be completed at 2645 Pacer Lane, San Jose, CA 95111
About Calvac Paving
Over the past 40-plus years, Calvac Paving has become one of the most experienced and reliable Asphalt and Concrete contractors in Central California. Our focus on individual project attention and meeting our STAKEHOLDER’S expectations has helped us to add scores of Property Managers/Owners, HOAs, Corporate buildings and campuses, Retail as well as Multifamily properties to our list of appreciative clients/stakeholders.
With winter and its accompanying rainfall on the way, the fall is a good time to take a look at your existing pavement and make sure it’s ready for the weather to come. Calvac Paving has been in the business for over 40 years, and in that time, we’ve learned a thing or two about how to solve small problems before they have a chance to become big ones. Now, we’re pleased to present this list of simple things you can watch for so your pavement lasts longer and looks and performs better in the process, even when the worst of the California winter weather strikes!
Do a routine walkthrough of your paved areas.
Parking lots and other paved areas should be checked at least semiannually for problems. Things to look for include:
- Areas of standing water. Water can break down the asphalt binder and leak down into the subgrade, eroding it over time. This is also an indication that the pavement or subgrade may already be failing, because modern grading techniques are designed to establish a grade that flushes water away from the parking area and toward designated drainage points.
- Oil or other chemicals that leak directly onto the pavement. Just like water, some chemicals associated with vehicles can cause binder breakdown and lead to subsurface problems. Cleaning up oil and other chemical spills as quickly as possible can help prevent this and keep your asphalt in better condition.
- Cracks, divots or uneven areas. These can be caused by weeds growing beneath the surface, freeze/thaw patterns, standing water and oil or ongoing heavy truck traffic. Small cracks and divots are often the first visible sign of possible asphalt breakdown, and it’s more cost efficient and less intrusive to fix them when they’re small by seal coating or spot patching than it is to do a complete tearout and reinstall of the paving.
- Striping: Old, dull or worn striping and pavement-level signage such as fire lane indicators and other information may be harder to see and read during winter months. Especially in ADA stalls, the striping and signage should always be clearly visible to make sure people know where these areas are.
Clear debris from drainage channels and curbs.
If water has nowhere to go, it doesn’t matter how good the drainage plan for your lot is. Making sure the drainage channels, storm sewers and other inlets to the runoff system near your property are clear of leaves, branches, garbage and other obstructions will help the water flow better and make it less likely to pool up on your property.
Limit or restrict heavy-vehicle traffic as much as possible.
Large trucks such as semis, garbage trucks and other heavy vehicles can place a lot of stress on asphalt. By itself this shouldn’t be a problem, but when the base course and subgrade are compromised by water or plant intrusion, it could speed up the breakdown process for the asphalt. If at all possible, try to limit, restrict or even out the traffic pattern for such vehicles within your lot to minimize the time they spend on your pavement.
Be sure it’s sealed.
Even if your parking area is free from cracks and other problems, it is a good idea to have it seal coated every 4 to 5 years at the minimum. This is because seal coating helps rejuvenate the asphalt binder at the surface, adding an extra layer of protection against traffic, water and other spills. Even better, it will help make your parking lot and driveways look newer, especially when you redo the striping at the same time. This makes your property more attractive, safer to navigate and less likely to fail for the long haul.
Seek professional help.
If you’re not sure if the paving problems you’ve identified are “big enough,” or if you think your pavement needs a facelift or a complete overhaul, Calvac Paving can help. We’ve been serving the Bay Area for over four decades with quality construction solutions including:
- Curb and gutter remediation, repair and replacement
- Paving rehabilitation, tearout and reconstruction
- ADA access compliance and signage
- And much more!
We take great pride in delivering a great product for your project, within the schedule and budget we agree upon. For more information about how Calvac Paving can help you with your paving or asphalt project, please contact us for a no charge estimate.
2645 Pacer Ln
San Jose, CA 95111
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 40 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.
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.
Every year, about 6 trillion cigarette butts are produced worldwide, or about 800 discarded butts for every man, woman and child on the planet. Not only are these butts an unsightly and expensive waste disposal problem, but the toxic chemicals which the filters trap and contain leach out over time to poison soil, groundwater, rivers and oceans. Now, a researcher at RMIT in Melbourne, Australia says he may have found a surprising answer to this problem: incorporate cigarette butts into asphalt aggregate!
According to the researcher, by coating the butts with a combination of paraffin wax and bitumen, the black substance also known as “tar” that gives asphalt its distinctive properties, it is possible to trap toxins which used butts contain while repurposing them as a lightweight, flexible asphalt aggregate component. This reduces the overall weight of an asphalt mix design while removing a potential 1.2 million metric tons of waste from the planet’s biosphere.
Another interesting side effect of adding cigarette butts to asphalt is the reduction of heat. Asphaltic concrete has been directly linked to the so-called “urban heat island” effect, caused by vast amounts of asphalt in a relatively small area. Cigarette filters are mostly made from cellulose acetate, a fibrous material which is spun down to look and feel like cotton. This material serves as an insulator which filters out toxins in cigarette smoke while helping prevent burnt fingers for those who simply must light up. These filters reduce thermal conductivity and reduce the thermal density of the mix. When placed as part of a roadway the asphalt containing the filters absorb and diffuse more heat, resulting in a cooler surface temperature and less radiant heat being redirected into the environment.
The final paper on this study states that butts coated with bitumen satisfied requirements for medium- and heavy-traffic mix designs. This would apply to interstates and surface streets with heavy commercial volume. Streets in residential neighborhoods, parking lots not marked for commercial vehicles and similar applications might use paraffin-coated butts. In the study, the research team used 10kg, 15kg and 25kg (about 22, 33 and 55lbs respectively) of encapsulated cigarette butts per cubic meter (1.30795cu.yd) to determine the ideal asphalt mix.
Since cigarette smoking on a global scale isn’t likely to go away anytime soon, finding new ways to deal with this waste is becoming a more pressing problem every day. Estimates claim that the mass of discarded cigarette butts may increase by as much as 50% by 2025 because of the increase in global population. Knowing this, recycling these butts into asphalt and other lightweight construction materials, as the author of the study proposes, may help us all breathe just a little bit easier.
At Calvac Paving, we know we only have one planet, and it’s up to all of us to care for it the best way we know how. There’s no reason that building a solid product and being ecologically responsible should be mutually exclusive, and we’re always on the lookout for new ways to incorporate green ideas into our building design.. We will keep a close eye on this and other “green” developments in construction materials, so we can continue to deliver the most environmentally sound products and processes possible without compromising on quality or durability. It’s all part of our commitment to make the communities we serve, and the world we all share, a safer and healthier place for everyone.
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 40 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:
2645 Pacer Ln
San Jose, CA 95111