Asphalt paving and supply projects require a firm with extensive industry experience that adheres to stringent quality control measures and provides consistent mix designs, adhering to specifications and offering compatible mix designs that adhere to industry guidelines. When searching for such firms, their service must meet such criteria as well. Choose the best Asphalt Paving Contractors Virginia Beach.
New asphalt construction entails six steps: milling existing pavement, grading and sloping for drainage, preparing the sub-base, adding a binder layer, and finally, laying new hot asphalt pavement.
Cold In-Place Recycling (CIPR)
Cold-in-place recycling (CIR) is a pavement rehabilitation technique that utilizes existing pavement materials while adding in recycled or new material without heating the mixture. CIR can remove existing asphalt pavement, such as rutting, cracking, and surface raveling, while also restoring the original road profile and slope without interruption to traffic flow.
Under the CIPR process, the existing pavement is milled to a specified depth before being milled again for recycling with foamed asphalt stabilizer and mixed into recycled material that will then be immediately back onto the roadway. One or more machines may perform this work, while for more complex jobs, an “equipment train” consisting of milling machines, crushers, modified milling machines equipped with stabilizing agent injectors (modified milling machine with injectors for stabilizing agents and water tanks for transport), pavers as well as compaction rollers may be employed – depending on scale – may be used for recycling efforts.
Stabilizers may include cement, lime, fly ash, and bituminous agents. Cement and lime act as pozzolanic additives to stiffen up stabilized base courses, while fly ash and bituminous agents reduce the shrink-swell properties of recycled aggregate, making it easier to form solid pavement surfaces.
Hot Mix Asphalt
Asphalt pavements are made up of stone, sand, and gravel bound together by asphalt cement derived from crude oil production. To create asphalt pavement, these ingredients must first be heated together at an HMA facility before being mixed on-site using a paving machine and spread by a heavy roller. Once cool enough to drive on, traffic may enter onto completed paved surfaces immediately.
Hot mix asphalt (HMA) is used in approximately one-third of all paving projects. Produced at temperatures ranging between 200-250 degrees, HMA requires less fossil fuel resources for its creation while offering more effortless pouring and spreading at lower temperatures. Furthermore, HMA contains various additives like wax, emulsions, and zeolites to make running and applying more straightforward.
As WMA is produced at lower temperatures, emissions, and odors are reduced both at the plant and on paving sites. Workers also report preferring this product due to its more relaxed working environment during placement and compaction.
Warm Mix Asphalt
Warm mix asphalt (WMA) can be produced at much lower temperatures, saving energy and carbon emissions while making handling much simpler on-site, with fumes, odor, and steam significantly reduced on-site. Contractors can then complete more work simultaneously with less disruption for motorists as road closures may be avoided altogether.
Lower temperatures also allow the material to be transported over longer distances at night, making it suitable for challenging construction situations such as tunneling. Warm mix can also be utilized more flexibly for flexible paving as it cools more slowly – ideal for low-temperature projects like winter paving.
Chemical additives like Rediset and Iterlow work at the microscopic interface between binder and aggregate to decrease frictional forces and ease the movement of asphalt mix particles across each other, leading to reduced mixing energy levels at lower temperatures [32]. Fischer-Tropsch wax Sasobit works similarly, increasing lubricity between aggregates and asphalt binder for improved coating of aggregates.
Asphalt Concrete
Asphalt is an immensely flexible material that can be used for roads, driveways, and other pavement projects. As an eco-friendly material, it helps reduce traffic noise as well as energy and fossil fuel consumption by vehicles. Furthermore, its smooth yet durable surface makes asphalt an excellent choice as it is resistant to damage caused by heavy vehicle loads compared to other pavement types.
Durability in asphalt pavements depends upon both its aggregates and binder. Aggregates must be strong enough to withstand vehicle weight stress, while asphalt binders need to bind the aggregate together effectively and endure high temperatures during mixing processes.
Air voids are another critical characteristic of asphalt pavement that allows it to expand with temperature changes without bleeding out or flushing away, without washing or bleeding through. Marshall stability and flow indicate a pavement’s ability to resist permanent deformation, while high resistance to stripping suggests it can withstand the removal of surface layers such as chip seals or overlays.
Geotextiles
Geotextiles are planar fabric structures constructed from synthetic polymers explicitly designed to be used in soil engineering and construction projects, such as roads, railways, airports, dams, and retaining walls. Used as part of artificial structures or projects such as roads, railways, airports, dams, retaining walls, etc., it helps separate different soil types, keep aggregates, prevent contamination, filter water, enhance drainage further, also serves as reinforcement material in pavements to prevent reflective cracking caused by repeated load cycles.
Choose the ideal type of geotextile for your project! Woven geotextiles have fixed openings and are impermeable, while nonwoven fabrics feature flexible structures and permeability. Woven fabrics provide greater tensile strength and filtration, while nonwoven geotextiles excel when it comes to high drainage needs.
Geotextiles can also be impregnated with asphalt to make them waterproof, increasing fatigue resistance and prolonging pavement lifespan. Furthermore, impregnation reduces reflective cracking under cyclic loads as well as rutting and shear deformation occurrence rates and is proven effective against both.
Read also: How to Properly Repair Your Asphalt Paving