When you have made the decision to pave your lot, driveway, etc., you have the option of paving materials such as asphalt, concrete, decorative bricks, and even individual pavers.
A significant percentage of property owners usually choose asphalt over other materials because an asphalt pavement lasts longer, looks better, and can quickly be installed. In a nutshell, asphalt is better for overall appearance, drivability, environment, and budget.
While you understand the importance of asphalt paving, it is also worth knowing that there are different asphalt types that can be used to serve particular needs.
So, what are the different types of asphalt?
Regarding the various asphalt types, there are lots of variations that could be used to meet particular needs. Nevertheless, the different asphalt types are listed but not limited to the following:
- Course Graded Asphalt
- Porous Asphalt
- Milled Asphalt
- Hot Mix Asphalt
- Warm Mix Asphalt
- Cold Mix Asphalt
- UPM
- MC Cold Mix
- Top Layer Asphalt
The different asphalt types have varying performance attributes in terms of braking efficiency, surface durability, roadway noise, and even tire wear.
But, which asphalt type is the best?
All the asphalt types are good and work well for various paving needs; however, it relies on the homeowner’s needs. In a nutshell, the best asphalt type you can use for your pavement is that mix with the perfect combination of price, efficiency-targeting overall value.
What is asphalt, and where does it come from?
Asphalt (also regarded as bitumen) is a semi-solid or liquid form of petroleum that is highly viscous, black, and sticky. It is a combination of binder, aggregates, and filler used to construct and maintain parking lots, driveways, roadways, etc.
Asphalt can be sourced from either natural deposits or as a by-product from petroleum distillation. It is made up of hydrogen and carbon compounds with minimal amounts of oxygen, nitrogen, and sulfur.
There are two primary ingredients in asphalt, including aggregates (mix of gravel, crushed stone, and sand) making up about 95% of it and bitumen (a petroleum residue) that make up the remaining 5%.
What is the process of making asphalt?
The manufacturing process of asphalt involves many steps. First, petroleum or crude oil is placed through a distillation process, separating the different oil components into many residues, of which one is asphalt. In simple terms, asphalt is just the dense deposits remaining after the oil refining process. The production process does not contribute to the different types of asphalt characteristics. The making process of asphalt include:
- Distillation
- Cutting Back
- Emulsifying
- Pulverizing
- Air Blowing
Distillation
The first step is speedily heating petroleum for initial distillation. After it has been heated, the crude is then transferred into a distillation container, where the removal of more evaporative and lighter-weight components takes place by a sequence of condensing and cooling techniques.
After that, the petroleum is separated into different producing products such as diesel, gasoline, kerosene, etc. The denser deposits remaining from the distillation process (often referred to as “topped” crude) are used to make other products such as asphalt.
Cutting Back
This step involves the blending of asphalt (known as “cutting back”) with a volatile material that creates a product that at a lower temperature is more pliable than chaste asphalt. The volatile elements vanish when the blended asphalt is subjected to heat or air, leaving behind only the solid asphalt. The evaporation speed of the cutting agent defines the asphalt curing rate.
Emulsifying
The next step is emulsifying asphalt to make a simpler substance to combine with aggregate, used in spray-on applications or inject via pipes. The asphalt is broken into granules thinner than five microns during emulsification and blended with water. The emulsifying agent is then applied to decrease the separation capacity of the asphalt and water.
Pulverizing
The next step is to pulverize hardened asphalt to create a powdered form. The asphalt is crushed and then transferred through a series of sieves to generate homogenous granules. Typically, powdered asphalt is mixed with aggregate and oil in constructing pavement.
Air Blowing
If asphalt is to be used for seal coating purposes, it may have air pumped into it in this step. In the course of the air-blowing process, asphalt will be heated to around 500°F. After then, air bubbles are pressured into the liquid over many hours; this ensures the asphalt remains in a liquid condition when cooled.
Types of asphalt mixes
The different types of asphalt mixes are as follows:
- Course Graded Asphalt
- Porous Asphalt
- Milled Asphalt
- Hot Mix Asphalt
- Warm Mix Asphalt
- Cold Mix Asphalt
- UPM
- MC Cold Mix
- Top Layer Asphalt
Course Graded Asphalt
This asphalt mix is rough and used to offer support for smaller mixes. It is usually used on driveways, parking lots, and roadways for surface lifts. Usually, these mixtures are often referred to as “binder mixtures” or base layers.
Pros:
- It lowers hydroplaning, decreases spray, and improves resistance to skidding.
Cons:
- This asphalt mix creates high porosity but may not have great bonding between the fine aggregates, offering required durability.
Porous Asphalt
This form of asphalt mix has barely visible holes in the material that help improve water maintenance by allowing water to flow via the pavement to the ground where it originally belonged. It is commonly used in parking lots to allow water to drain via the pavement surface.
Pros:
- It enhances stormwater management and increases skid resistance
- It needs less energy to produce
- It substantially mitigates smoke, emissions, and odor.
Cons:
- It is not suitable for heavily-trafficked areas; hence, almost exclusively used for driveways, patios, and walkways.
- It’s generally not a good option for commercial parking lots that experience a lot of traffic.
Milled Asphalt
Milled asphalts are a by-product of rejuvenated asphalt pavement. The process involves grinding up the top layer of old asphalt into new asphalt. Milled asphalts are often used as a substitute for hot asphalt and stone gravel. It is less expensive and can withstand harsh weather elements compared to the other types of asphalt.
Pros:
- It is cost-effective
- It reduces demand on aggregate
- It enables percolation.
- It is environmentally friendly.
Cons:
- It offers varying quality that is not up to the standard of new asphalt
- The color is not as deep as conventional fresh asphalt
Hot Mix Asphalt
Hot asphalt is the type of asphalt used for paving and patching roadway, driveway, parking lots, etc. Hot asphalt under elevated temperature is the easiest to work with. It offers a lasting solution to asphalt pavement issue but must be used almost instantly after purchase; because if allowed to cool, it becomes more difficult to deal with. Once fully cool, it solidifies like a rock.
Pros:
- It is very durable
- Able to withstand wind, flooding, etc.
- Can stand up against the weather elements
- It is usually used for highways, driveways that experienced high traffic due to its flexibility
Cons:
- It is more costly than other mixes
- It may only be installed when the outdoor temp is 40 degree or above
Warm Mix Asphalt
Warm-mix asphalt is made similar to that of hot-mix asphalt, although it is 50 to 100 degrees Fahrenheit lower. The main advantage of hot-mix asphalt is the environment, as it uses less compacting exertion during construction and, as a result, releases less CO2. Warm-mix asphalt appears to be more costly but is a realistic alternative for anyone seeking “green solutions.”
Pros:
- It saves resources and energy as a result of lower mixing temperatures
- It enhances working conditions compared to other types of asphalt mixes
- Pavement built with this mix can be opened to traffic almost immediately due to its early curing time
- It does not cause wear and tear to asphalt plant construction tools
- It is inexpensive
Cons:
- It poses moisture damage risk
- Finding the correct balance is hard.
Cold Mix Asphalt
Cold-mix asphalt stays soft at any cold temperature and keeps water off very well at any temperature. It is primarily used for fixing potholes. Cold-mix asphalt has a short lifespan due to its soft nature; hence, it should be used only as a temporary material for repair works or last resort for repairs.
Pros:
- It is affordable
- It can be installed even in colder temperatures
- It repels water at any temp.
Cons:
- It is commonly used in temporary conditions, such as patching potholes and filling cracks during winter months
UPM
UPM is a type of asphalt that is formed to work under any weather condition. It can be used to offer a permanent solution to any problem of asphalt pavement. UPM is usually used for repairing both dry and wet potholes, enabling you to carry out any repair under any situation. Once you compact UPM, it will be ready immediately for use. It is specifically designed to fix large asphalt pavement issues. You can use it without requiring any special equipment to fill your pavement potholes.
Pros:
- It is easy to use
- It is cost-effective
- It works well under any weather condition
- It can be used throughout the year unlike the other types of asphalt mixes.
Cons:
- It is suitable for only pavement repairs and is not commonly used for installing high-trafficked driveways.
MC Cold Mix
This asphalt mix is a temporary cold mix material used for patching. It is slow to cure and is mostly used in pavement sections that require a temporary patch. It is suitable for light-duty traffic or in small places that are not frequently used by vehicles and usually hold up well. You can stockpile this asphalt mix and use it later on.
Pros:
- The flashpoint of MC Cold Mix is much higher than the traditional medium cured asphalt
- It is not necessary to cool aggregate as much as when traditional stockpile mixes are made.
Cons:
- It is slow to cure
- It is only suitable for constructing light-duty traffic pavement
Top Layer Asphalt
Top layer asphalt is the most widely used asphalt mix. It is usually laid once heated to a temperature between 300 to 350 °F. This asphalt mix is used as a final layer that is aesthetically pleasing due to its smaller stone feature that forms a compact surface appearance when compacted.
Pros:
- It is pocket friendly
- It reduces noise pollution
- It offers a comfortable ride
- Aesthetically appeal
Cons:
- It tends to need more maintenance
The recycling process of asphalt
Asphalt recycling is the method by which used asphalt materials are reclaimed and reprocessed to make fresh and usable products. Recycling asphalt will save you lots of dollars. Many homeowners prefer recycled asphalt to the other types of asphalt because it does not lose its quality or longevity, matches the quality of new materials, and is often of a higher grade. Below are the process involved in the recycling of asphalt:
- The first step here is the asphalt milling. This step involves the dismantling of the asphalt top layer from the pavement without touching the sub-base.
- After asphalt milling, it is then taken to the factory for the next round of processing. In the asphalt factory, recycled asphalt is screened and resized via many procedures. Besides, it is used to produce new pavement.
- In the case of hot mix asphalt, the mix is plummeted and heated for about 20 minutes before it is set for use. Conversely, cold recycling does not make use of heat, saving energy in the process.
- The asphalt cement (known as the glue holding together the pavement) often maintains its binding capabilities and can be used again as an adhesive.
- It is also possible to reuse the tiny mineral particles produced in the production process of asphalt pavement material, which helps in conserving natural resources.
Reasons asphalt is the ideal paving product for recycling
Asphalt is one of the suitable paving products for recycling due to its numerous impressive advantages. Asphalt durability, weather resistance, and strength do not diminish after several years of usage. They are also extremely crack-resistant because of abundant organic fibers and fillers in recycled materials.
Below are the attributes and properties, making asphalt the top material for recycling:
- The paving product is highly porous, enabling water to drain via it to the ground level.
- Excessive flexibility helps modify the same as per temperature
- It helps prevent damage due to its oil-resistant
- It can handle extreme loads
- It is unlikely to rut or crack
- It is very durable
- Its jet-black look enhances the appearance
- It is not costly to maintain
Conclusion
The various types of asphalt provide effective solutions to asphalt issues that you may have in your business or home. By understanding the differences, you will ensure you choose the correct one for your case. It would be best to take a close look at each type and what it has to deliver to figure out which one would work well for your surface needs.
Notwithstanding, it’s highly recommended to employ the help and support of skilled professionals in the asphalt field to achieve the best outcome. Professional asphalt paving contractor can advise you on any asphalt mix that best suits your project and can provide more extended life cycle costs, best value for your investment, and assured top quality.