Asphalt paving
what is asphalt pavement?
Asphalt pavement is renowned for its exceptional durability and resilience, making it the ultimate choice for a wide range of paved surfaces. Its unmatched strength has earned the trust and preference of both state and federal governments, thanks to its reliability and long-lasting nature. When properly laid, asphalt pavement can endure for an impressive twenty to twenty-five years without needing replacement.
Moreover, asphalt pavement reigns supreme as the most popular option for various applications, including driveways, parking lots, roadways, and even airstrips. Its versatility knows no bounds, as it can be found virtually everywhere. Surprisingly, asphalt also holds the distinction of being the most commonly recycled material in the United States, surpassing even paper or plastic. An astounding 80% of all asphalt pavement is recycled when it is removed, highlighting its sustainability and environmental benefits.
What makes up asphalt pavement?
Asphalt pavement is composed of stone (aggregate), sand, additives, and liquid (petroleum) asphalt. Liquid asphalt, a sticky black substance, serves as the binding material in asphalt pavements. It can be found in both viscous and semi-solid forms and is commonly referred to as bitumen.
Once mixed, the pavement consists of 90 to 95% aggregate and sand, with 5 to 10% asphalt or bitumen. The high viscosity of asphalt binds the materials together while maintaining flexibility. The flexibility of asphalt pavement is a key advantage, allowing it to adapt to varying weather conditions and the ever-changing surface beneath it.
The cooler the asphalt surface, the less flexible the overall pavement becomes. This flexibility is one of the major strengths of asphalt pavement, enabling it to withstand the effects of weather and adapt to the constantly shifting surface below.
Another key characteristic of asphalt is its remarkable water-repellent property. This attribute holds immense significance since, as we shall soon discover, water poses the most formidable threat to the integrity of asphalt surfaces. Consequently, it is this very reason that drives the existence of asphalt contractors like yourself, who play a pivotal role in this industry.
Asphalt Paving Process and methods
Are you considering an asphalt paving project in the near future? If so, it is crucial to comprehend that asphalt installation can be a highly intricate and involved process. While the actual installation of the asphalt may not demand a significant amount of time, the design, demolition, and preparation stages can be quite time-consuming.
Undertaking an asphalt paving project requires careful planning and attention to detail. It is essential to ensure that the area is properly prepared before the asphalt can be laid. This involves conducting a thorough assessment of the site, including evaluating the existing surface, checking for any potential drainage issues, and determining the appropriate thickness and composition of the asphalt.
Design the surface
At Bituminous Roadways, we leverage cutting-edge GPS technology and AutoCAD software to meticulously survey, design, and prepare project sites, ensuring an astonishingly precise design error of less than one inch across the entire site.
Demolition and Removal
The initial step in the asphalt installation process involves the elimination of the existing surface, be it asphalt, concrete, or pavers.
This task is accomplished through the utilization of heavy machinery, such as small bobcats and forklifts, and if necessary, front loaders and large dump trucks.
Once the debris has been cleared, we at asiagilsonite take pride in our commitment to recycling. Our asphalt plants are equipped to transform worn-out asphalt and concrete into robust, usable new asphalt. In fact, asiagilsonite is renowned for recycling nearly 100% of the materials extracted from each job site. This not only makes asiagilsonite an environmentally friendly choice but also a sustainable one.
Grading and Sloping
With a fresh start, technology aids Asiagilsonite’s asphalt professionals in preparing the surface for effective water drainage.
By utilizing laser-guided transits and automatic motor graders, the Asiagilsonite team meticulously grades the surface to be paved, guaranteeing optimal water runoff.
Ensuring proper water drainage is crucial for your asphalt’s longevity, as water serves as a primary catalyst for various damages, such as potholes, cracks, and heaving.
Prepare Sub-base and Installation
Although it may go unnoticed, the sub-base is an indispensable element of any asphalt pavement installation. Its significance cannot be overstated, as it serves several crucial purposes.
Firstly, a well-prepared sub-base acts as a protective shield against the detrimental effects of frost heave resulting from the cyclical freezing and thawing of the ground.
Secondly, it establishes a sturdy foundation capable of withstanding the weight and traffic load of the newly laid pavement. This stability is essential to ensure the longevity and resilience of the surface.
Lastly, the sub-base provides a substantial, compacted, and reliable support system for roads or parking lots, thereby enhancing their overall durability over time.
Proof Rolling, Strategies for Effective Sub Base Repair
Once the subbase has been thoroughly graded and compacted, asiagilsonite carries out an additional step known as a proof roll to guarantee the strength and readiness of the underlying surface for supporting new asphalt.
The asiagilsonite proof roll entails the utilization of a quad-axle dump truck, loaded with a substantial weight of 72,000 pounds, systematically driving over the entire surface, row by row.
Should the gravel exhibit flexing of more than an inch under the immense weight of the truck, it indicates an inadequate level of support in the base.
If the proof roll identifies any soft areas in the sub base, asiagilsonite takes immediate action to rectify the issue and ensure the overall stability of the sub base.
One effective method employed by asiagilsonite is undercutting, which involves excavating the ground below the surface by 2 or 3 feet and replacing the weak clay or soil with more robust aggregate material. This process effectively strengthens the compromised areas.
In addition to undercutting, asiagilsonite offers alternative solutions such as the utilization of geo-grid. This innovative approach involves excavating only 16 inches below the surface and laying down a grid to connect the base materials. This creates a solid support structure for the new asphalt, all while significantly reducing costs compared to traditional undercutting methods.
Furthermore, asiagilsonite has pioneered a groundbreaking technique known as plowing. This method involves undercutting the sub base, but instead of completely removing the soft clay and soil, it is mixed with additional aggregate to enhance the strength of the compromised areas. This innovative process ensures a more efficient and cost-effective solution.
By employing these advanced techniques, asiagilsonite guarantees the utmost quality and durability of the sub base, providing a solid foundation for any asphalt project.
Install the Base Course
The base course refers to the layer of aggregates and binder that is positioned directly above the compacted sub-base or subgrade, depending on the specific project and its requirements.
Once the material has been evenly distributed, we proceed to compact it, thereby enhancing the strength and stability of the asphalt pavement that will be placed above it.
Install New Asphalt Surface
After the installation of the supportive structures for a new asphalt surface, a top layer of fresh asphalt is added to ensure a clean and smooth ride.
The surface asphalt consists of small aggregates, sand, and oil.
This unique blend of materials results in a jet-black asphalt that, when properly installed, offers a smooth and glossy finished surface, enhancing its visual appeal.
Install New Asphalt Surface
Installing an asphalt surface that does not connect to existing driveways, roadways, or parking lots is an exceedingly uncommon occurrence. Consequently, asphalt-paving contractors face the challenge of seamlessly integrating the new surface with the old.
Joints refer to the specific locations where old asphalt or concrete meets the newly paved asphalt pavement. These transitional areas demand meticulous attention to guarantee proper grading and effective water run-off.
The significance of joints lies in their ability to ensure that drivers and pedestrians remain oblivious to any disparities between the surfaces. By carefully addressing these areas, contractors can ensure a smooth and uninterrupted experience for all users.
Final Roll
Once the asphalt and joints have been laid, the entire surface is carefully smoothed and compacted. This crucial step guarantees that no small bumps of aggregate or stone are left protruding through the newly laid surface. It is imperative that your asphalt paving contractor adheres to these installation steps to ensure that your new asphalt surface will withstand the test of time and serve its purpose effectively, whether it is for your home, business, city, or town.
However, it is important to note that the installation process should only commence after a thorough surface inspection and a comprehensive estimate have been conducted.
Gilsonite in Asphalt and Road Paving
Gilsonite is a naturally existing mineral resin that has earned significant attention in recent years due to its universal application in the construction industry. One of its most popular uses is in road paving and asphalt sulfonated production.
This unique mineral has properties that enhance the quality of the paving asphalt, making it more durable and long-lasting. The black, shiny, and brittle uintaite is found in several locations across the globe. It has a high molecular weight and is composed of complex hydrocarbons, including aromatic compounds and resins. This mineral is highly soluble in petroleum-based solvents and has low toxicity, which makes it the best choice in the construction industry. We’ll discuss the use of gilsonite in road paving and its benefits as well as the method of asphalt pavement and more in the following article.
Types of asphalt
Asphalt Paving Methods
The infrastructure industry has introduced many methods for asphalt paving. Here are these methods:
Hot Mix Asphalt (HMA) Paving
This method involves heating the mixture of asphalt and aggregate to a temperature above 300 degrees Fahrenheit and using it for paving. This type of paving is commonly used for high-traffic areas like highways.
Warm Mix Asphalt (WMA) Paving
In this method, the mixture of asphalt and aggregate is heated to a lower temperature of around 200-250 degrees Fahrenheit. This reduces the emission of harmful gasses and saves energy, making it an eco-friendly option.
Cold Mix Asphalt Paving
This is a low-temperature, energy-saving method of paving asphalt that is used for repairs and patching. The mixture of asphalt and aggregate is applied at ambient temperature, making it suitable for use in areas with less traffic.
Porous Asphalt Paving
This type of paving is designed to allow water to pass through the surface and into the ground below. Porous asphalt consists of a graded aggregate and a binder that is mainly used for parking lots and sidewalks.
Permeable Interlocking Concrete Pavers (PICP)
This method involves using interlocking pavers to create a porous surface that allows water to seep through. PICP is commonly used for driveways and walkways.
Gilsonite Application in Asphalt Paving
The application of gilsonite in asphalt paving has been embraced worldwide, and industries are continuously seeking new ways to optimize the use of the mineral. The Uinta Basin in Utah remains the primary source of gilsonite globally, with approximately 90% of the total global production originating from the area.
Gilsonite-modified asphalt is often used in a range of asphalt mixtures, including hot mixes, warm mixes, and cold mixes. It is also used in surface and base courses for roads and runways. Some of the common applications of Gilsonite in paving asphalt are:
– Pavement Sealers
Uintaite is used as an additive in pavement sealers to improve their adhesion, durability, and waterproofing properties.
– Hot-Mix Asphalt
Gilsonite-modified asphalt mixtures are commonly used in road construction and repair. The use of this mineral can improve the performance of the pavement by reducing rutting, cracking, and deformation.
– Cold-Mix Asphalt
Uintaite can also be used in cold-mix asphalt, which is typically utilized in colder temperatures. The addition of Gilsonite can improve the stability and durability of cold-mix asphalt.
– Grouts and patching compounds
Another application of gilsonite is that it can be utilized as an additive in grouts and patching compounds to improve their adhesion and strength.
– Crack fillers
To improve the flexibility and adhesion of crack fillers, specialists use gilsonite as an effective ingredient.
Benefits of Gilsonite in Asphalt Paving
Gilsonite has a high resistance to wear and tear, which means that asphalt pavement mixed with it can last longer and handle heavier traffic loads. Also, when the durability of the asphalt pavement increases, it improves the pavement’s lifespan by reducing the need for frequent repairs and maintenance.
The inclusion of gilsonite in asphalt increases the pavement’s elasticity and flexibility, making it less likely to crack and pothole when subjected to freeze and thaw cycles. This is because Gilsonite’s unique molecular structure allows it to stretch and bend without breaking, making it more resistant to temperature changes and other environmental factors.
Gilsonite has hydrophobic properties that improve the pavement’s water resistance, preventing damage from freeze-thaw cycles. Paving asphalt is not inherently waterproof, so adding Gilsonite to asphalt sulfonated mixtures increases the pavement’s resistance to water penetration. This enhances the pavement’s durability in areas with high rainfall, snow, and ice, reducing potholes and other related pavement damage.
Asphalt exposed to UV radiation can lose its color and become brittle with time. Gilsonite, being a natural UV absorber, can help slow the process of oxidation.
As compared to other additives that achieve similar results, gilsonite is often more cost-effective due to its lesser amount required in the mix. Besides, gilsonite improves the quality of the asphalt, less material is needed to achieve the same performance as traditional asphalt, reducing the amount of money spent on construction.
Gilsonite is a natural and organic mineral that doesn’t contain any hazardous chemicals, making it an eco-friendly option. Moreover, Gilsonite has a low carbon footprint, which makes it an environmentally friendly alternative to petroleum-based binders. This makes the use of uintaite in paving asphalt and road a sustainable choice for the construction industry.
What Does the Gilsonite-Modified Asphalt Mixture Consist of?
Gilsonite-modified asphalt mixtures typically consist of asphalt sulfonated binder mixed with Gilsonite (usually in the range of 8-12% by weight of the binder). The exact composition may vary depending on the specific application and the properties desired.
In addition to Gilsonite, other materials such as polymers and aggregates may be added to the mixture to further enhance its properties. These additives can improve the mixture’s durability, elasticity, and resistance to deformation.
The process of producing Gilsonite-modified paving asphalt involves heating the asphalt binder to a specific temperature (typically between 150-170°C) and then adding the uintaite. The mixture is then thoroughly mixed and processed to ensure that the mineral is dispersed evenly throughout the mixture.
Asphalt Paving and Surface Preparation
Before the asphalt is applied, the surface must be prepared correctly to avoid any problems related to the infrastructure.
Paving asphalt is typically prepared using a hot mix asphalt (HMA) plant. HMA is made up of asphalt binder, aggregates (such as gravel, sand, or crushed stone), and often other additives such as polymers or fibers.
The process of mixing and preparing asphalt involves heating the aggregates to a specific temperature and drying them. This is typically done by first passing them through a dryer drum. Meanwhile, the asphalt binder is also heated to a specific temperature and is kept hot in a storage tank.
Once the aggregates are hot and dry, they are combined with the hot asphalt binder in a mixing plant. This mixture is typically mixed for several minutes to ensure that the asphalt binder completely coats the aggregates.
The mixed asphalt paving is then transported to the job site in trucks and is typically placed using a paving machine. The mixture is spread evenly and then compacted with a roller to ensure a smooth and uniform surface.
Overall, the mixing and preparation of asphalt involves precise control of temperatures and mixing times to produce a high quality product that can withstand the demands of traffic and weather.
Here are the steps for asphalt pavement:
Cleaning the Surface
The surface of the pavement or roadway must be cleaned off any debris, dirt, and loose material so that the new asphalt can adhere firmly. It’s done either by sweeping, power washing or by using a vacuum truck.
Inspection
The surface should be inspected and identified to figure out the degree of damage to the existing pavement, the depth of the base material, existing cracks, potholes, or other defects.
Repairs
Any existing defects should be repaired before the new paving asphalt is added. This includes filling potholes, repairing cracks, and fixing any other damage to the surface.
Grading and leveling
When the surface has been cleared and repairs have been made, it is vital to grade and level the surface. This is necessary to determine how much asphalt sulfonated is required to be added and to ensure that the surface is even.
Tack Coat
Before laying new asphalt down, a tack coat is administered on the surface so the new asphalt will stick and form a stronger bond.
Adding New Asphalt
The asphalt paving process then begins by adding a fresh, hot asphalt layer in a predetermined thickness.
Finishing
Once the asphalt is placed, it is spread and compacted using a compactor roller to provide a smooth finish that is level and compressed.
Curing period
After the asphalt has been spread, steps are taken to ensure that it cools down gradually and is allowed to dry completely. This will create a long-lasting paving asphalt surface.
The Dosage of Gilsonite in Asphalt Sulfonated
The dosage of gilsonite in asphalt sulfonated can vary depending on the specific requirements of the project and the properties of the gilsonite being used. Generally, uintaite is added at a rate of 5-8% by weight of the total asphalt binder content in the mixture when used in combination with sulfonated asphalt.
However, it is important to note that the optimal dosage of gilsonite for a particular project may vary depending on factors such as the properties of the paving asphalt binder being used, the temperature and climate conditions, and the desired performance characteristics of the final asphalt surface. Therefore, it is recommended to consult with a gilsonite supplier or a qualified engineer to determine the appropriate dosage for a specific project.
