What is sandstone?
Where does the sand and gravel come from? Sandstone is one of the common materials in construction engineering, and there are many kinds, such as sandstone. In the process of building construction, we will use sandstone, which is divided into natural graded sand and graded sand. Let's see what sandstone comes from.
Where does sandstone come from? 1 1. Is sandstone a building material?
Belonging to building materials, sandstone is actually loose, but the particles are generally hard and chemically stable in the surface environment. For sandstone, its weathering resistance is generally strong, especially silicified sandstone, which can be said to be harder than granite.
Second, the sand and gravel use matters needing attention
1, the factory certificate and test report of sand and gravel must be the same as the physical evidence between objects. The factory certificate must be stamped by the quality inspection department of the manufacturer, and the test report must be signed by the relevant personnel of the testing unit and stamped by the unit.
2, in the use of units must carefully check whether the measured values in the product factory certificate and test report meet the standards stipulated in the specification. We should also have the test number in the test report to facilitate verification with the relevant information of the laboratory. The test report should have a clear conclusion and complete signature and seal.
3. The construction materials related to the sand and gravel factory certificate and test report include construction organization design, technical disclosure, business records, construction logs, application forms and notices of concrete and mortar mixture ratio, compressive strength reports of concrete and mortar test blocks, hidden inspection records, quality acceptance records, as-built drawings, etc. So we say that its certificate and test report should not only be the same as the actual projects and parts, but also correspond to the above construction data one by one.
Even what is gravel?
It belongs to a kind of sandstone, which is made of sandstone, and its size is generally about 0.074 mm to 2 mm, and even the intermediate matching of sandstone can be used to make concrete blocks. Its price is determined according to the size of sandstone structure, because its particle size and thickness are different, so the blocks made are definitely different.
Gravel is a loose material, granular and very hard. Even if it is used in the surface environment, its chemical properties are very stable and will not be affected by the surrounding environment. When purchasing, you need to ask the merchant to show the quality certificate and relevant inspection report, so as not to affect the construction quality.
Matters needing attention in the use of sand and gravel
1. Building materials such as sandstone must have factory certificates and quality inspection reports. At the same time, the quality certificate must be stamped and signed by the relevant departments.
2. The relevant units using sand and gravel must carefully check the ex-factory quality of sand and gravel to see if it is consistent with the values and standards on the test report. If the test number is wrong, it cannot be used and must be verified with the laboratory.
3. Because the quality of sand and gravel is directly related to the engineering quality, the quality must be verified before use. If there are size differences or other quality problems, then it is not recommended. In addition, the units on the certificate and proposal report must be consistent with the actual situation and must be carefully checked.
Where does the sand and gravel come from? Sand and sand have similar meanings, both referring to stone particles in granular state and other substances with similar shapes to these stone particles. But there is still a big difference between sand and gravel, such as:
1, from the Chinese point of view:
"Sand" means "loose stone particles in water". Generally, fine-grained loose stones obtained from or related to water are represented by "sand". "Sand" refers to naturally occurring stone particles such as sand, beaches and sand springs, while "desert" is different.
"Sand" means "finely divided stone", which generally refers to substances as fine as sand and stone particles formed after ore is crushed.
Literally, the two are different, one is related to water and the other is related to stone.
3. Sand can be processed by hand, but not by sand.
1. What is natural graded sand?
Natural graded sand refers to sand and gravel, which is a mixture of sand and gravel. There is no on-site configuration and mechanical mixing, and the sand and gravel are close to the design requirements. Compared with graded sand, natural graded sand lacks viscosity and is easily destroyed by water. Natural graded sand is usually used to pave the road base. When it is used, it is usually mixed with cement and other adhesiveness to improve the adhesiveness of natural sandpaper.
Second, what should I pay attention to when using sand and gravel?
1. When sand enters the construction site, we need to check and accept it. For example, we need to check whether the sand and gravel have the certificate and inspection report. Everyone should also check the particle size and silt content of each car's gravel, and unqualified gravel cannot be unloaded. Because the diameter of sand and gravel is too large, it will lead to pump blockage. Excessive mud content in sand and gravel will affect the quality of concrete mortar and so on.
2. Sand and gravel are usually used with cement. When using sand and gravel, we must first determine its proportion and the amount of sand and cement. If too much or too little sand is used in the process of preparing cement mortar, it will affect the quality of concrete mortar and so on.
3. The water content of sand and gravel changes greatly. We measure the moisture content of sand and gravel at any time when preparing concrete, and adjust the water consumption of concrete mortar. If the construction environment temperature is low, when preparing concrete mortar, the sand can be heated before use, and so on.
What is gravel? 1. What is sand?
I believe many people have heard of it, but have you really understood it? Sand mainly refers to a loose mixture of sand and gravel. Geologically, minerals or rock particles with a particle size of 0.074~2mm are called sand, and those with a particle size larger than 2mm are called gravel or breccia. If the gravel in the sand is mostly gravel, it is called gravel. In daily life, some people call sandstone sandstone.
(1)
Mineral detritus: mainly timely and feldspar.
Debris: it is related to the surrounding environment of the field production site or the rock types exposed in the upper reaches of the river.
Cements: There are still cements in rocks, and different sandstone cements are different. Common ones are generally calcareous, siliceous, iron and argillaceous.
(2) Features
The structure of different sand bodies is very different, some particles are uniform in thickness, and some particles are different in size; Some sand chips have good roundness, while others have sharp edges and corners. Sand is loose, but the particles are generally hard, and its chemical properties are very stable in the surface environment. For sandstone, its weathering resistance is generally strong, especially silicified sandstone, whose hardness exceeds granite.
(3) Use
Because of its good hardness and stable chemical properties, sand is often used as high-quality building materials and concrete raw materials, and is widely used in houses, roads, highways, railways, engineering and other fields.
As for sandstone, it has been an important building material for large-scale buildings, stone carving, interior decoration and garden courtyard construction since ancient times.
(4) reasons
1. natural origin: rocks and stones in nature are broken and separated into particles of different sizes through surface actions such as weathering and denudation. Under the action of water, wind, glaciers, etc. These particles are transported and aggregated to form a gravel layer. Sandstone layers formed before Quaternary (2-3 million years ago) basically formed rocks, that is, all kinds of sandstone, glutenite and so on. However, all kinds of gravel, gravel sand and gravel formed in Quaternary period are either solidified into rocks or called Quaternary loose deposits. Natural sandstone, also called natural sand.
2. Man-made reasons: The material made by human crushing stones through sand making machines and other equipment is generally called machine-made sand.
Second, what is a gravel foundation?
Sandstone foundation generally refers to a kind of compaction pile foundation, which is a commonly used soft soil foundation treatment method. Sand piles and sand piles are collectively referred to as sand piles. Using vibration, impact or water to form holes in soft foundation, sand or pebbles or gravels and gravel are squeezed into the holes to form a dense pile body composed of large-diameter sand or pebbles (gravel). This kind of foundation is generally economical, simple and effective. It can be used to treat loose sand foundation, soft clay foundation, plain fill, miscellaneous fill and other foundations.
Sand pile and gravel pile are collectively referred to as gravel pile, which means that sand or gravel (gravel, gravel) is squeezed into soil holes after being bored by vibration, impact or water in some soft foundations to form a dense pile body composed of large-diameter sand or gravel (gravel, gravel).
This is a common soft foundation treatment method. Scope of application: Sand and gravel pile foundation is mainly suitable for compacted loose sand, plain fill and miscellaneous fill. For projects built on saturated cohesive soil foundation, deformation is not the main controlling factor, and gravel piles can also be used for replacement treatment.
I have given you a very detailed introduction about what a gravel foundation is. I believe you can learn more now. Some people may find it unnecessary to understand. In fact, these are all very wrong ideas. Knowing this can also help you build your own house without being cheated, so I think it is very necessary to learn.