What are the benefits of asphalt pavement?
• Asphalt is 20-40% cheaper than concrete.
• It is safe, economical, and the most long-lasting and durable paving material.
• Asphalt pavement is 100 percent recyclable.
• Asphalt pavements provide the user with a smooth, quiet, safe ride surface.
• Properly designed, built, and maintained asphalt pavements enhance vehicle safety by providing a renewable, skid-resistant surface.
Q. What is the Difference Between Asphalt and Concrete?
A.Asphalt & concrete are two construction materials which are commonly used around the world. The primary difference between the two is that asphalt is made by mixing aggregate with bitumen, a sticky black hydrocarbon which is extracted from natural deposits or crude oil. Concrete is made by mixing an aggregate material with a cement binder & then allowing the mixture to harden, forming a rock-like substance. Asphalt is used for different construction tasks, ranging from roofing to driveways, footpaths, roads etc. Concrete is applied cold and a combination of cement, rocks (sometimes–aggregate) and water. Concrete is a harder substance and will not soften up with high temperatures. Asphalt will become more soft and pliable under high heat.
An easy way to remember the different between asphalt & concrete is that asphalt is usually black to brown in color, & has a distinctive texture, while concrete is greyish in colour & looks more like rock.
Q. How widely is asphalt used? A. About 94 percent of the nation’s roads and highways are surfaced with asphalt.
Q. Are asphalt pavements quieter than other types of pavement? A. Yes, there is considerable research that shows that asphalt pavements tend to be quieter than concrete pavements on the whole.
Q. How long will my pavement last? A. The success of your pavement depends on three factors:
Thickness and type of pavement installed.
Thickness and type of sub-grade (crushed rock) provided. Based on the material type the contractor/engineer can determine the strength coefficient with sub-grade to support a given pavement. Lower ratios require thicker cross sections of pavement to support the pavement and provide appropriate longevity.
Frequency and type of traffic driving across a given pavement section will impact performance and longevity. Remember, one heavy duty loaded truck driving across that given section of pavement is the equivalent of 10,000 cars driving across the same section of pavement! These variables will impact longevity of pavement and are critical in building or maintaining your pavement in a satisfactory condition.
Q. What causes asphalt deterioration? A. Some of the most common causes of asphalt deterioration are oxidation, water accumulation in low-laying areas due to improper drainage, excessive loads on the asphalt and the destructive effects of vehicle oil and gasoline. Over time, water accumulations can cause asphalt to crack and split severely or “alligator,” as it is commonly referred to in the paving industry. Bearing excessive weight can cause the asphalt to sink and oil and gasoline that seep into the asphalt cause further deterioration.
Q. I just paved a new parking lot. When should I seal it? A. You should wait at least 90 days to allow the oils to settle in and dry out. It is appropriate to seal after paving because it will fill in any areas that remain porous and will establish the beginning of a regular maintenance cycle. Unfortunately, most people are reactionary, rathan than preventative with regard to asphalt maintenance and wait to seal until after damaging has already happened.
Q. How much does it cost? A. Factors that will affect our prices are: units (i.e. square feet, lineal feet, etc.) condition of the asphalt, how much prep work may be required, and obstacles that will affect, such as carports, curb stops, etc. When seal coating, asphalt in relatively good condition does not require nearly as much material and can be completed at a much lower cost, while older, “thirstier” asphalt, can require much more material. Patchwork is significantly more expensive than seal coating per foot. Striping, patch work, and any other services can be itemized on your bid so you can pick and choose what you wish to have done.
Q. When can I seal? A. The typical season for asphalt sealing in the Rocky Mountain area runs from late May through early October. High temperatures for the day are preferred to be above 60 degrees and it cannot rain.
Q. When can I patch? A. Typically year-round.
Q. When can I stripe? A. Throughout the seasonal spring and summer months and year-round if the air is sufficiently dry.
Q. How often should I seal? A. Depending on the amount of traffic and the weather conditions, it is a good idea to seal every 2-3 years.
Q. What can be done about cracks? A. Crack filling will be done in advance of the seal coating process. In general, only seam-line cracks exceeding one-quarter inch will be filled, but this will be specified in the bid proposal. The asphalt sealer can adequately fill tiny cracks. We use a product called Dura-fill Heat Stabilized Crack Filler, which is heated to roughly 400 degrees, at which temperature it can be poured into the exposed joint or crack. It will cool and harden inside the crack, preventing moisture penetration. Affected cracks will be cleaned appropriately prior to being filled with either manual or motorized brooms and/or compressed air. Extended cracking or “gator areas” should be repaired with asphalt hot mix, not rubberized crack filler.
Q. What type of prep work is required for asphalt sealing? A. To ensure the best coverage, the asphalt surface must be clean of dirt, oil spots, moss, and any other debris prior to sealing. Most surfaces can be cleaned with wire brooms and with a device called a Powerbroom, which is similar to a weedeater with circulating bristle heads. Once the necessary debris is dislodged from the asphalt surface it will be blown clean with the high-powered backpack blowers and/or Billy Goat parking lot cleaning equipment. A pressure washer will be used on rare occasion when moss is particularly heavy. Pressure washing must be done in advance of the seal coating process to allow time for the water to dry.
Q. Will you repaint my parking stall lines, handicap stencils, etc.? A. Yes. We can include striping in your bid. We also perform striping and parking lot design for new construction projects.
Q. Can Asphalt Pavement Be Used For Heavy Loads? A. Asphalt pavement is the pavement of choice for big or small parking lots, expansive shipping yards, areas for material handling, railroad facilities, airports, etc., because it can take the weight and the punishment.
Q. How long do I need to wait before driving on a sealed driveway? A. We recommend waiting 24 hours or at least overnight.
Q. What is the most critical factor in a good asphalt job? A. The base is the most important factor in an asphalt job. If the base is not installed thick enough it will not bear the load and the asphalt on top of the base will also fail. Nine times out of ten, if the asphalt is cracking, the base is too thin.
Q. How thick should the base be? A. As a rule of thumb, for every inch of asphalt, 2 inches of road base should be used.
Q. What does the base do? A. The base will interlock and spread the load of the vehicles weight.
Q. How thick should the asphalt be? A. Asphalt thickness is based at compaction. A minimum of 2 inches is used for overlays; a minimum of 3 inches for new lays.
Q. How long do you have to work asphalt when it is layed down? A. Only a few minutes before it starts to cool down and become unworkable
Q. What is asphalt sealer coat? A. Sealer is a water base coal tar emulsion that is applied to asphalt.
Q. What does sealer do? A. It protects the asphalt from drying out (oxidation). It also protects the asphalt from water and oil damage. Sealer works much the same way as when you paint wood.
Q. What are the most critical factors for a good seal coat? A. First, the asphalt needs to clean. and next is the rate of application. I recommend fifty square feet to the gallon.
Q. When is it too cold to place concrete? A. It depends. Normal concrete will not set or harden when the concrete temperature is below about 35F. Many times specifications will say something like “Concrete may not be placed when the temperature is 37F and falling.” With heated water and aggregates, accelerating admixtures, and other methods, jobs can be placed below freezing, but it is more expensive. In most southern states there are so few freezing days that it is not worth it to try to place concrete when the temperature is below freezing.
Q. When is it too hot to place concrete? A. It depends. High temperatures (90F and above) cause concrete to set or harden faster. High temperatures also can reduce the ultimate strength of concrete. Strong winds and low humidity can also cause problems with plastic shrinkage and drying shrinkage potential, even at moderate temperatures. To avoid these problems, planning, timing of the finishing operations, proper use of retarding admixtures, and proper curing are necessary.
Q. What is architectural/decorative concrete and how much more does it cost? A. There are many types of colored and stained concrete: Some with simple texture, some with unique patterns, some with color only and no texture. The cost may vary from $1.00 – $7.00 additional per square foot. Enright Companies has been doing decorative concrete for about 8 years now.
Q. Is colored/stamped concrete durable? A. Yes, in fact with proper care the wear surface is actually 25% more durable.
Q. Does integral colored concrete fade? A. No, the color will not fade if it is maintained.
Q. Do I need to maintain my concrete? A. Yes, you need to maintain your concrete. We will seal your concrete the first time for curing reasons (twice for decorative concrete). We recommend you reapply a sealer prior to winter or after 30 days and then once every 3 years after.
Q. Will my concrete crack? A. Cracking from shrinkage is normal and characteristic of concrete. Enright Companies uses control joints in the building process on both horizontal and vertical concrete to try to control cracking.
Originally a naturally occurring product in use for centuries the early 1900’s brought today’s refined petroleum product. This term is often applied to almost any asphalt product from H.M.A.C. to asphalt cements and oils.
A dark brown to black cementitious material in which the predominating constituents are bitumens which occur in nature or are obtained in petroleum processing. In varying proportions, asphalt is a constituent of most crude petroleums.
Generic term for material installed prior to asphalt paving. May be a crushed stone product or asphalt product (see full-depth asphalt pavements). The base material provides the load bearing characteristics of the finished pavement and may vary from 3-4″ for a residential driveway to 18″ or more for parking areas or roadways. The correct type and amount of base material must be determined and specified prior to paving. Lack of adequate base material is a primary cause of pavement failures.
Common “slang” term for asphalt. However this term should not be used in requesting any specifications or work as the term is widely used with various meanings in different areas. For example sometimes “blacktop” is used to refer to a penetration pavement or hot oil treatment (see fog seal).
Course, Asphalt Base
A foundation course consisting of mineral aggregate, bound together with asphalt material.
Course, Asphalt Surface
The top course of an asphalt pavement, sometimes called asphalt wearing course.
Mechanically produced combination of ingredients which do not normally mix. For example, asphalt emulsions are made by a procedure which mechanically mills the warm asphalt into minute globules, dispersing them in water, and adding a small amount of an emulsifying agent.
A process of applying a highly diluted asphalt emulsion in a fine spray (fog) to a roadway surface. Restores blackness and seals hairline cracks, may prevent or slow oxidation. Not generally used for parking facilities due to tracking.
Full-Depth Asphalt Pavement
The process of constructing an asphalt pavement structure using asphalt products for all components. The base material and surface courses are all made up of appropriately specified grades of hot-mix asphalt in contrast to conventional paving using crushed stone materials etc. There are numerous benefits to this method of construction. The Asphalt Institute has excellent detailed information about this process.
H.M.A.C. Hot Mix Asphalt Concrete
Abbreviation of the proper name for what is commonly referred to as “asphalt”, “hot-mix”, “blacktop” etc. This term should always be used in specifying asphalt pavement work to avoid any confusion or misinterpretation of the material desired. H.M.A.C. is produced in many different grades from coarse base mixes to specialized mixes for surfacing and repair. In most instances the grades are specified according to state department of transportation guidelines.
The portion of the asphalt paving process where the hot asphalt is actually placed or “laid down” by the paving machine.
A term used to describe the fresh asphalt surface behind the paving machine. Most commonly used to refer to the asphalt during the laydown and compaction phase of construction.
A coating of asphalt oil either cutback or specialized emulsion, used to seal the sub-base and/or base material and enhance bonding to the asphalt course.
Cracks in an asphalt overlay pavement caused by cracks in the existing pavement “reflecting” up through the overlay. Specialized techniques and materials such a multi-membrane paving fabrics help reduce this problem.
Enlargement of pavement cracks using a specialized machine. This provides a uniform width reservoir for the sealant. Proper choice of bit size will result in the proper depth to width ratio (depth=width). Properly used this procedure greatly increases the effectiveness and durability of crack sealing.
Application of a sealant (usually coal-tar emulsion or asphalt emulsion type) to preserve, protect, and beautify asphalt pavements. Generally used on low traffic streets or off-street locations. There are many different sealcoating products available from low-end “do-it-yourself” grades sold in buckets to commercial products. Commercial products are sold in bulk in concentrated form. Water, silica sand (or other suitable aggregates) and specialized additives are then added in precise ratios (mix design) by the contractor in an agitated mixing tank. Care should be taken to choose the appropriate product, mix design, and application method for the specific project and it’s location.
A sealcoating process generally used on runways, streets, and roadways. In this process the coating is manufactured by the application equipment as it is being applied. A closely specified blend of graded asphalt emulsion, additives, and aggregate slurry seal is generally classified as Type I, II, or III depending on the size of aggregate used. A large aggregate slurry seal with additional polymers may also be referred to as micro surfacing. Used infrequently on parking areas due to the potential for tracking in hot weather.
The soil prepared to support a structure or a pavement system. It is the foundation for the “pavement structure.”
Asphalt oil, usually emulsion type, applied to existing pavement during repairs or overlay paving to create a bond between the old and new asphalt.