Q-What are the different types of Gravel?
A-Multiple types of gravel have been recognized, including;
Bank gravel: gravel intermixed with sand or clay.
Bench gravel: a bed of gravel located on the side of a valley above the present stream bottom, indicating the former location of the stream bed when it was at a higher level.
Creek rock: This is generally rounded, semi-polished stones, potentially of a wide range of types, that are dredged or scooped from river beds and creek beds. It is also often used as concrete aggregate and less often as a paving surface.
Crushed Rock: Crushed Rock is mechanically broken into small pieces then sorted by filtering through different size mesh.
Crushed Stone: This is generally Limestone or dolomite that has been crushed and graded by screens to certain size classes. Hence the name “crushed stone“. It is widely used in concrete and as a surfacing for roads and driveways, “driveway gravel” sometimes with tar applied over it. Crushed stone may also be made from granite and other rocks. A special type of limestone crushed stone is dense grade aggregate, or DGA, also known as crusher run. This is a mixed grade of mostly small crushed stone in a matrix of crushed limestone powder. Crushed stone is is very commonly used for driveways. The most common sizes of crushed stone is range from 3/8 crushed stone, 5/8 crushed stone, 3/4 crushed stone, 1 1/2 crushed stone, 2 1/2 crushed stone. You may be able to find crushed stone in other sizes as well.
Fine gravel: gravel consisting of particles with a diameter of 1 to 2 mm.
Lag gravel: a surface accumulation of coarse gravel produced by the removal of finer particles.
Pay gravel: also known as “pay dirt”; a nickname for gravel with a high concentration of gold and other precious metals. The metals are recovered through gold panning.
Piedmont gravel: a coarse gravel carried down from high places by mountain streams and deposited on relatively flat ground, where the water runs more slowly.
Plateau gravel: a layer of gravel on a plateau or other region above the height at which stream-terrace gravel is usually found.
River run gravel: naturally deposited gravel found in and next to rivers and streams.
Defined by wikipedia.com
Q- What are the types of Aggregate materials used in the building and construction Industry?
A-Construction aggregate, or simply “aggregate”, is a broad category of coarse particulate material used in construction, including sand, gravel, crushed stone , slag, and recycled concrete . Aggregates are a component of composite materials such as concrete and asphalt concrete; the aggregate serves as reinforcement to add strength to the overall composite material. Aggregates are also used as base material under foundations, roads, and railroads.The American Society for Testing and Materials publishes an exhaustive listing of specifications for various construction aggregate products, which, by their individual design, are suitable for specific construction purposes. These products include specific types of coarse and fine aggregate designed for such uses as additives to asphalt and concrete mixes, as well as other construction uses. State transportation departments further refine aggregate material specifications in order to tailor aggregate use to the needs and available supply in their particular locations. Sources for these basic materials can be grouped into three main areas:
Mining of mineral aggregate deposits, including sand, gravel and stone;
Use of waste slag from the manufacture of iron and steel;
Recycling of concrete , which is itself chiefly manufactured from mineral aggregates.
In addition, there are some (minor) materials that are used as specialty lightweight aggregates: clay, pumice, perlite, and vermiculite.
Defined by Wikipedia.com
Crushed stone and or rocks supplied in the Northeast generally include 3/8″ Crushed Stone, 5/8″ Crushed Stone, 3/4″ Crushed Stone, 1 1/2″ Crushed Stone, 2 1/2″ Crushed Stone, Stone Screenings, and “DGA” Dense Graded Aggregate. All crushed stone materials have different uses and applications. Below is a brief overview of the different types of uses crushed stone has in the construction, building and landscaping industries.
• Stone Dust or Stone Screenings – Stone Dust is used as a base for paving blocks & base for concrete paved roads and areas such as horse arenas
• 3/8″ Crushed Stone - 3/8 inch crushed stone is usually bluish to grayish in color. It is a clean stone that is used for driveways, drainage, and is often mixed with asphalt.
• 5/8″ Crushed Stone – 5/8 inch crushed stone generally has the same look and applications as 3/8 inch crushed stone, only it is slightly larger
• 3/4″ Crushed Stone - 3/4 inch Crushed Stone is also blue to gray in color, but its larger size has some additional uses. 3/4 inch Crushed Stone is used in driveways, but it is also used for around trees, landscaping, French drains, and as a sub-base for concrete sidewalks, concrete driveways, and patios,
• 1 1/2″ Crushed Stone - 1 1/2 inch Crushed Stone like most crushed stone, is blue or gray. It is primarily used for drainage, septic systems, and as a road base
• 2 1/2″ Crushed Stone - 2 1/2 inch Crushed Stone is blue or gray. These largest of the crushed stone products are used primarily for septic systems, & tracking pads on job sites.
• 3/4″ DGA – DGA or Dense Graded Aggregate is a combination of crushed stone and gravel created in a quarry process. Dense Graded Aggregate is used as a base material for driveways or walkways, road base, or a base for interlocking walls.
If you have any questions on what type of crushed stone to buy for your project call Tom at 917-912-2900
Below is a statistacl report about crushed stone.
Statistical Compendium by U.S. Geological Survey, Minerals Information
Commodity Specialist: Valentin V. Tepordei (email@example.com) Last modification: 11/04/97
Stone, in its multitude of forms, represents a very significant part of the Earth’s crust and one of the most accessible natural resources. Stone has been used since the earliest days of our civilization, first as a tool or weapon, then as construction material, and later, in its crushed form, as one of the basic raw materials for a wide variety of uses ranging from agriculture and chemicals to complex industrial processes. At the beginning of the 20th century, the U.S. production of crushed stone was relatively small, and its uses limited. Today, crushed stone is being produced in 48 of the 50 States, and its annual production tonnage ranks first in the nonfuel minerals industry. The United States is, in general, self-sufficient in crushed stone, producing enough to meet most of the domestic needs. Small quantities of crushed stone, used mainly as construction aggregates, are being imported mostly by water from the Bahamas, Canada, and Mexico to compensate for local shortages that exist in some areas of the country.
The demand for crushed stone is determined mostly by the level of construction activity, and, therefore, the demand for construction materials. U.S. production of crushed stone recorded a significant growth in the past 40 years, from 229 million metric tons in 1950 to 1.1 billion metric tons in 1990. The highest level of production was reached in 1988–1.13 billion metric tons. Between 1950 and 1973, because of the construction of the Interstate Highway System, the growth from year to year in the production of crushed stone was almost continuous, paralleling the increased demand for construction aggregates. Following the reduction in the volume of work in the Interstate Highway Program in the late 1960’s, the crushed stone industry, while still growing, became more sensitive to the ups and downs of the economy. The 1974-75 and 1982 recessions are well reflected by low levels of production of crushed stone in those years. Future demand for crushed stone will continue to be dependent mostly on the growth of construction activity.
Most crushed stone is used for construction purposes, mainly as aggregate with or without a binder. Road base or road surfacing material, macadam, riprap, and railroad ballast are the major uses without a binder. Aggregate for cement and bituminous concrete in highway and road construction and repair and in residential and nonresidential construction are the major uses for aggregates with a binder. Other uses include cement and lime manufacture, agriculture, metallurgical flux, and fillers and extenders.
Crushed stone is a high-volume, low-value commodity. The industry is highly competitive and is characterized by thousands of operations serving local or regional markets. Production costs are determined mainly by the cost of labor, equipment, energy, and water, in addition to the costs of compliance with environmental and safety regulations. These costs vary depending on geographic location, the nature of the deposit, and the number and type of products produced. Despite having one of the lowest average-per- ton values of all mineral commodities, the constant dollar price of crushed stone has changed relatively little during the past 20 years. As a result of rising costs of labor, energy, and mining and processing equipment, the average unit price of crushed stone increased from $1.58 per metric ton, f.o.b. plant, in 1970 to $4.39 in 1990. However, the unit price in constant 1982 dollars fluctuated between $3.48 and $3.91 per metric ton for the same period. Increased productivity achieved through increased use of automation and more efficient equipment was mainly responsible for maintaining the prices at this level.
Underground operations are becoming more common, especially for limestone mining in the central and eastern parts of the United States, as the advantages of such operations are increasingly recognized by the producers. By operating underground, a variety of problems usually connected with surface mining such as environmental impacts and community acceptance are significantly reduced.
Transportation is a major factor in the delivered price of crushed stone . The cost of moving crushed stone from the plant to the market often equals or exceeds the sale price of the product at the plant. Because of the high cost of transportation and the large quantities of bulk material that have to be shipped, crushed stone is usually marketed locally. The high cost of transportation is responsible for the wide dispersion of crushed stone quarries around the country, usually located near highly populated areas. However, increasing land values combined with local environmental concerns are moving crushed stone quarries farther from the end-use locations, increasing the price of delivered material. Economies of scale, which might be realized if fewer, larger operations served larger marketing areas, would probably not offset the increased transportation costs.
Although crushed stone resources are widespread and in adequate supply nationally, local shortages exist. Land use conflicts and environmental problems associated with rapid urban expansion are major factors contributing to these shortages. The local shortages that occasionally exist are caused less by a lack of stone than by urban encroachment or zoning regulations that force closure of operating quarries or prevent the development of new ones. Demand pressures, land use regulations, and the cost of meeting environmental and reclamation requirements are factors that will cause a rising price trend.
Sand and gravel and to a lesser extent iron-blast-furnace slag are the predominant substitutes for crushed stone used as construction aggregate. Steel slag is another substitute for crushed stone in road bases and asphaltic concrete, but not in cement concretes because of chemical interaction. Blast-furnace slag is also used as a stone substitute in cement manufacturing.
Crushed Stone remains an abundant material, and, despite environmental, zoning, and regulatory restrictions, no shortages on a large scale are expected to occur in the future.