What Is China Clay?

Clay is sticky soil with few sand particles, and it is not easy for water to pass through to have good plasticity.

[nián t]

Clay is very sandy and sticky

Word : clay

Pinyin : nián t

Phonetic :

Explanation : Sticky dirt.

Example : "Book · Yugong" "Ju Tu Chi Tu Grave" Kong Biography "Soil Sticky Grave" Tang Kong Yingda Shu: "" Kao Gong Ji "uses soil as a tile, which is called brick work, because the work is clay, so the soil is stick Said . " ^[1]

Clay, also known as clay, is a plastic aluminosilicate with very small particles (<2m). In addition to aluminum, clay contains small amounts of magnesium, iron, sodium, potassium, and calcium, and is an important mineral raw material.

Clay generally consists of

Clay

Clay is a type of layered silicate. The layer is composed of silicon-oxygen tetrahedron and aluminum-oxygen octahedra.

According to their structure, they are divided into the following four categories:
The Kaolinite Group, type 1: 1.
The Montmorillonite / Smectite Group, 2: 1 type.
The Illite (or The Clay-mica) Group, 2: 1 type.
The Chlorite Group, 2: 1: 1.

According to the nature and use, it can be divided into ceramic clay, refractory clay, brick clay and cement clay. Hard clay is often block-like or plate-like, generally does not disperse in water, has high fire resistance, and is the main raw material of refractory products. The hard clay in refractory clay is used to make blast furnace refractories, ironmaking furnaces, hot blast stoves, lining bricks for steel buckets, and plug bricks. In the ceramic industry, hard clay and semi-hard clay can be used as raw materials for making daily-use ceramics, building porcelain and industrial porcelain.

Paper

It is also called "pulp clay" in China. Ingredients include pulp, gum,

Clay minerals are widely distributed in rocks and soils around the world. The bentonite mineral resources in the world are above 1.3Gt, mainly distributed in the United States and Canada. Kaolin mineral reserves are about 1.6Gt, mainly distributed in China, the United States, the Soviet Union, Mexico, Spain and other countries. China is a country rich in kaolin resources, with excellent minerals and complete genetic types. The main producing areas are Suzhou, Jiangsu, Junxian, Hubei, and Xuyong County, Sichuan. active

Making ceramics

Industrial clay ore includes kaolin, bentonite (mainly composed of montmorillonite), activated clay (indefinite composition), and so on. Kaolin was first mined by China in Gaoling Village, Jiangxi, to make ceramics. Bentonite began to be mined in Wyoming, USA in 1888, and activated clay was first mined in Texas, USA in 1906.

Cement

Cement mixed with limestone

use

Modeling in industry, model making and art. Artists use clay to make models, but clay can also be used to directly shape artworks

High liquid soil

The three indexes for judging the high liquid limit soil in the project are: soil with particle content less than 0.074mm greater than 50%, liquid limit greater than 50%, and plasticity index greater than 26. The design idea of high-liquid-limiting soil with expansive properties for slope engineering is basically based on the expansive soil. In addition to the characteristics of swelling and shrinkage due to water, the more important feature is that the high-liquid-limiting soil has poor compaction. The compacted soil is still relatively compressible, and has obvious strain softening. Many slope projects lose their effectiveness due to the inability to identify the essential characteristics of high liquid limit soils.

High liquid limit soil

High liquid limit soil usually contains a large amount of clay components such as montmorillonite, illite, kaolinite. Montmorillonite is a mineral composed of extremely fine-grained hydrous aluminosilicate. Its lattice unit is composed of two layers of silicon-oxygen tetrahedron sandwiched by a layer of alumina octahedron. The interlayer connection depends on Fan Dehua force, which is weak. Water molecules easily enter between the unit cells, increasing the unit cell distance. After dehydration, corresponding shrinkage occurs, and the liquid limit change range can reach 140 to 710%, and the plastic limit range is 50 to 100%. Due to the isomorphic substitution effect, montmorillonite has a strong adsorption capacity, and a large amount of Na + and Ca2 + are filled in, which results in an electric double layer effect and causes intergranular expansion. Similarly, illite also has a three-layer crystal structure of 2: 1, but the main cations it adsorbs are Na + and K +. The inter-lattice connection is strong, and water molecules are not easy to enter. Therefore, illite is hydrophilic and swells. It is not as good as montmorillonite, and its liquid limit varies from 80 to 120%, and its plastic limit is 45 to 60%. Illite is a relatively unstable intermediate product. Its properties are between montmorillonite and kaolinite. The interlayer K + content gradually decreased, and was close to montmorillonite. Kaolinite's structural unit is a unit cell composed of a layer of aluminum hydroxide wafer and a layer of silicon oxide wafer. The connection between the unit cells is the hydrogen bond between the oxygen atom and the hydroxyl group. The bonding force is strong, the distance between the unit cells is not easy to change, water molecules cannot enter, and the hydrophilicity and swelling are higher than the first two mineral components. . The engineering properties of high liquid limit soil are related to its parent rock composition, water content, compactness, external load size and mode of action, and other physical and chemical effects. According to a large number of engineering practices, it is known that high liquid limit soils have poor water permeability; high strength when dry and hard, hard to dig, and difficult to compact; obvious capillary phenomenon, which can retain water for a long time after water absorption, so the bearing capacity is small and the stability is poor after water absorption ; Has greater plasticity, weak expansion and viscosity.