Aggregates Delivery & Trucking
Aggregates typically do not travel very far. The average distance, largely due to economic factors, that trucks can carry aggregates over the road is 50 miles—thus making aggregates the ultimate local product. However, to conserve resources and reach more customers Summit Materials also uses barges and railroads at operating locations with those services available. For example, Mainland Construction Services ships about 65% their aggregates via barge and rail car.
Basic Steps for Road Construction
Phase #1: Planning and Design
Excavation, earthwork and paving are what most people think of when they hear the words 'road construction'. However, long before the first shovel is ever lifted, countless hours go into planning and design. Below are just a few of the items that must be considered before beginning road maintenance with a Summit Materials company:
- Traffic volume and location
- Terrain and soil properties
- Utility lines, drainage, and sewers
- Climate, environmental, and residential requirements
- Future expansion possibilities
- Road maintenance costs
Phase #2: Excavation and Earthwork
The area of land where the roadway, parking lot, subdivision, park, or building site will be placed will first need to cleared of all vegetation including trees, shrubs, buildings, fences or environmental related issues. Once the 'rough grading' has been started or in some cases completed the underground utilities begin to take shape.
Grading: Rough Grading is one of the first steps to shape the existing site into the newly designed shape to accommodate drainage, sidewalks, roadway surfacing, lakes, ponds, decorative landscape areas, and other aspects of the area.
Utilities: This will usually begin with the deepest utility going first followed by other utilities that are closer to the natural ground surface. Generally, this will begin with sewer, followed by storm drainage systems, culinary water, irrigation water, as well as dry utilities including electrical and natural gas lines.
Fine Grading: Once the utilities are installed fine grading of the site takes place to shape the existing surface to accommodate fill, road base, sidewalk, asphalt paving, curb and gutter as well as landscape areas designated on the plans. The fine grading will be finished to tolerances that are within ¼” of the designed subgrade requirements.
Aggregating and Hard Surfacing: Once the fine grading takes place and the subgrade is within the design tolerances, depending on existing soil conditions and the design requirements, granular borrow, fill and aggregate base course which is manufactured by Summit Materials operating companies with aggregates facilities will be hauled and installed to the desired thickness and tolerances. Once the aggregates have been placed the subsequent hard surfaces are then incorporated into the project including concrete paving, asphalt paving, curb and gutter, sidewalk, pedestrian trails, bike trails, and more .
Phase #3: Asphalt Paving
During this final phase, the asphalt is placed and compacted to tight specifications for optimal performance. Take note: depending on the estimated traffic volumes and regional climate conditions, the asphalt paving job can require up to four different layers of asphalt:
Gravel Layer: Also known as the frost blanket, a mixture of gravel and sand is laid to minimize the effects of freezing and thawing temperatures.
Base Layer: Using bitumen, cement, or lime as the predominant binder, a bound base course is laid over the unbound base course.
Surface Layer: Responsible for providing friction, smoothness, noise control, and drainage, the surface layer is composed of the highest quality materials.
Asphalt also has a limited delivery area. The quality of the product depends on efficient delivery routes and paving operations. Depending on the location, our operating companies will simply deliver the asphalt, in others they will pave, and still in other locations, they will install a portable asphalt plant at a large job site to shorten the delivery time as much as possible.
Summit Materials is committed to sustainability throughout all lines of business, including services. Our various locations used approximately 780,000 tons of recycled asphalt pavement (RAP) and recycled asphalt shingles (RAS) in 2017. In addition to using RAP and RAS to reduce the amount of virgin materials used, Summit Materials reuses nearly 400,000 tons of recycled concrete on an annual basis. Furthermore, Summit reduces its energy consumption at its cement plant by more than 30% by operating a hazardous waste disposal site at our operating company, Continental Cement Company (CCC) CCC, through its subsidiary, Green America Recycling (GAR). GAR is one of a handful of companies that is licensed to burn hazardous materials in the United States. This process is a sustainable and safe way to dispose of these chemicals so that they do not end up in landfills and reduce our reliance on fossil fuels.
Additionally, our operating company Hamm, operates a recycling center in Lawrence, Kansas that saved approximately 9,970 tons of material from landfills in 2017. Hamm also installed a methane gas capture system at their landfill (methane gas is a normal byproduct of decomposing trash). The plant is expected to produce more than 4 million tons of fuel annually by capturing and cleaning the methane gas. Please read more about our commitment to recycling in the sustainability portion of our website.