Quarter minus is a type of construction aggregate that is usually made from crushed basalt (but can be made of other rock types) from which the crushed rock product is not any bigger than 1/4" in diameter. The quarter minus rock size can consist of rock in diameter as big as 1/4" in size and "fines" (anything smaller than the maximum allowable rock size (which in this case is 1/4), even as small as stone dust). Any aggregate with the name "minus" can contain up to 80% fines. Quarter minus is mostly used as filler aggregate for bigger aggregate, empty space between two different sized aggregate, vehicle parking grade, and landscape surfaces. A positive of using quarter minus as a landscape aggregate is that it does not provide a home for pests and does not decompose like other landscape aggregates like wood-chips, for example. [1] [2]
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus. The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies. Sedimentation may also occur as dissolved minerals precipitate from water solution.
Gravel is a loose aggregation of rock fragments. Gravel occurs naturally throughout the world as a result of sedimentary and erosive geologic processes; it is also produced in large quantities commercially as crushed stone.
A crusher is a machine designed to reduce large rocks into smaller rocks, gravel, sand or rock dust.
A pebble is a clast of rock with a particle size of 4–64 mm (0.16–2.52 in) based on the Udden-Wentworth scale of sedimentology. Pebbles are generally considered larger than granules and smaller than cobbles. A rock made predominantly of pebbles is termed a conglomerate. Pebble tools are among the earliest known man-made artifacts, dating from the Palaeolithic period of human history.
The Japanese dry garden or Japanese rock garden, often called a zen garden, is a distinctive style of Japanese garden. It creates a miniature stylized landscape through carefully composed arrangements of rocks, water features, moss, pruned trees and bushes, and uses gravel or sand that is raked to represent ripples in water. Zen gardens are commonly found at temples or monasteries. A zen garden is usually relatively small, surrounded by a wall or buildings, and is usually meant to be seen while seated from a single viewpoint outside the garden, such as the porch of the hojo, the residence of the chief monk of the temple or monastery. Many, with gravel rather than grass, are only stepped into for maintenance. Classical zen gardens were created at temples of Zen Buddhism in Kyoto during the Muromachi period. They were intended to imitate the essence of nature, not its actual appearance, and to serve as an aid for meditation.
Earthbag construction is an inexpensive building method using mostly local soil to create structures which are both strong and can be quickly built.
A mill is a device, often a structure, machine or kitchen appliance, that breaks solid materials into smaller pieces by grinding, crushing, or cutting. Such comminution is an important unit operation in many processes. There are many different types of mills and many types of materials processed in them. Historically mills were powered by hand or by animals, working animal, wind (windmill) or water (watermill). In modern era, they are usually powered by electricity.
Aggregate is the component of a composite material that resists compressive stress and provides bulk to the composite material. For efficient filling, aggregate should be much smaller than the finished item, but have a wide variety of sizes. For example, the particles of stone used to make concrete typically include both sand and gravel.
In the field of extractive metallurgy, mineral processing, also known as ore dressing, is the process of separating commercially valuable minerals from their ores.
A gravel road is a type of unpaved road surfaced with gravel that has been brought to the site from a quarry or stream bed. They are common in less-developed nations, and also in the rural areas of developed nations such as Canada and the United States. In New Zealand, and other Commonwealth countries, they may be known as metal roads. They may be referred to as "dirt roads" in common speech, but that term is used more for unimproved roads with no surface material added. If well constructed and maintained, a gravel road is an all-weather road.
A rocker box is a gold mining implement for separating alluvial placer gold from sand and gravel which was used in placer mining in the 19th century. It consists of a high-sided box, which is open on one end and on top, and was placed on rockers.
Construction aggregate, or simply aggregate, is a broad category of coarse- to medium-grained particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are the most mined materials in the world. Aggregates are a component of composite materials such as concrete and asphalt; the aggregate serves as reinforcement to add strength to the overall composite material. Due to the relatively high hydraulic conductivity value as compared to most soils, aggregates are widely used in drainage applications such as foundation and French drains, septic drain fields, retaining wall drains, and roadside edge drains. Aggregates are also used as base material under foundations, roads, and railroads. In other words, aggregates are used as a stable foundation or road/rail base with predictable, uniform properties, or as a low-cost extender that binds with more expensive cement or asphalt to form concrete. Although most kinds of aggregate require a form of binding agent, there are types of self-binding aggregate which do not require any form of binding agent.
A sieve analysis is a practice or procedure used in civil engineering and chemical engineering to assess the particle size distribution of a granular material by allowing the material to pass through a series of sieves of progressively smaller mesh size and weighing the amount of material that is stopped by each sieve as a fraction of the whole mass.
Soil gradation is a classification of a coarse-grained soil that ranks the soil based on the different particle sizes contained in the soil. Soil gradation is an important aspect of soil mechanics and geotechnical engineering because it is an indicator of other engineering properties such as compressibility, shear strength, and hydraulic conductivity. In a design, the gradation of the in situ or on site soil often controls the design and ground water drainage of the site. A poorly graded soil will have better drainage than a well graded soil, if it is not high in clay quality.
Mechanical screening, often just called screening, is the practice of taking granulated or crushed ore material and separating it into multiple grades by particle size.
Crushed stone or angular rock is a form of construction aggregate, typically produced by mining a suitable rock deposit and breaking the removed rock down to the desired size using crushers. It is distinct from naturally occurring gravel, which is produced by natural processes of weathering and erosion and typically has a more rounded shape.
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass.
Otta seal is a type of bituminous surface treatment that was developed by the Norwegian Road Research Laboratory (NRRL). Its name is based on the location in which it was created, the Otta Valley. Otta seal was developed to be used as a temporary surfacing on new roads; however, after seeing its strength, it has been used as permanent roads as well.
A cobble is a clast of rock defined on the Udden–Wentworth scale as having a particle size of 64–256 millimeters (2.5–10.1 in), larger than a pebble and smaller than a boulder. Other scales define a cobble's size differently. A rock made predominantly of cobbles is termed a conglomerate. Cobblestone is a building material based on cobbles.
Tunnel rock recycling is a method to process rock debris from tunneling into other usable needs. The most common is for concrete aggregates or as subbase for road building. Crushers and screeners normally used in quarries are stationed at the tunnel site for the purpose which is to crush and screen the rock debris for further use. The largest tunnel rock recycling facility ever to be created was for the construction of the Gotthard Base Tunnel which took 17 years, finishing in 2016. 1/5 of the rock debris excavated for the tunnel was recycled and used as aggregates for the concrete lining inside the tunnel.