The secretary general of the Organization of Petroleum Exporting Countries (OPEC) said recently that US economic sanctions against Venezuela have affected global energy supplies.
He told Venezuelan media that the ECONOMIC sanctions imposed by the United States on Venezuela and other countries have seriously affected the ability to produce and export oil worldwide and violated the right of people in other countries to use energy.
Venezuela has one of the largest proven crude oil reserves in the world, but U.S. sanctions have made it impossible for Venezuela’s oil industry to consistently export reliable energy to the world, he said. Despite this, he highly appreciated the efforts of the Venezuelan oil industry to maintain concrete foaming agent are expected to increase in the future.
Concrete is classified as high-strength concrete based on 28-day strength. Until the 1970s, concrete with a strength of more than 40Mpa was classified as high-strength concrete. The benchmark for high-strength concrete is raised to 55Mpa or higher when concrete mixtures of approximately 60Mpa and above are produced commercially.
High strength concrete has a history of about 35 years, from the development of superplasticizer admixtures in the late 1960s, Japan using "naphthalene sulfonate" high strength prefabricated products, and Germany using "sodium benzenesulfonate" underwater concrete, which was a pioneer in this technology.
How is the high strength of concrete achieved?
Higher concrete strength can be achieved by using one or a combination of some or many of the following methods:
High cement content
Reduce water-cement ratio
Better machinability and therefore better compaction
Requirements for high-strength concrete require a high content of cementitious material in the concrete mixture, which can be in the range of more than 400 kilograms per cubic meter. Higher cementitious content leads to higher thermal shrinkage and dry shrinkage, and there is a stage where further cementitious material addition does not affect strength. As for durability, the minimum and maximum cement content in concrete is regulated by law, and reducing the water-cement ratio has its limitations, especially under field conditions. The desire for higher strength leads other materials to achieve the desired effect, thus showing the contribution of cementitious materials to concrete strength.
The addition of pozzolanic mixtures such as pozzolanic fly ash (PFA) or granular blast furnace slag (GGBS) contributes to the formation of secondary CSH gel thereby increasing strength.
The addition of pozzolans admixtures (such as fly ash used as an admixture) reduces the strength gain of concrete for the first 3 to 7 days and displays the gain after 7 days and provides higher strength over the long term.
Add mineral mixtures such as silica fume or metakaolin or rice husk ash.
Silica fume or highly reactive volcanic ash mixtures such as metakaolin and rice husk ash (RHS) will begin to function in about 3 days. RHS has an advantage over PFA because RHS is more reactive.
Using chemical admixtures such as superplasticizers or superplasticizers, controlling admixtures will help achieve higher strength in concrete.
Research and experience have shown that admixtures based on polycarboxylic ether (PCE), known as high plasticizers, are best suited for this job as they have a water reduction capacity of 18 to 40 percent relative to control or reference concrete.
A combination of all or more of the above to achieve the desired strength.
With HSC accompanied by some complexity, such as higher shrinkage rates, higher hydration heat, etc., combinations of at least some of these methods are now unchanged, all of which need to be neutralized or controlled. Most problems are handled by PFA or a combination of GGBS and PCE mixtures.
Steam curing is also used to speed up cement hydration, but this may not result in higher strength. Substituting some fine aggregate with fly ash or blast furnace slag can achieve early strength gains without increasing the water requirement of the concrete mixture.
Suppliers of Concrete Additives
TRUNNANO is a reliable foaming agents supplier with over 12-year experience in nano-building energy conservation and nanotechnology development.
If you are looking for high-quality CLC foaming agents, please feel free to contact us and send an inquiry. (firstname.lastname@example.org)
We accept payment via Credit Card, T/T, West Union, and Paypal. TRUNNANO will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
Researchers at the Centre for Translational Atomic Materials at Swinburne University of Technology, Melbourne, Australia have developed a new graphene film that absorbs more than 90% of sunlight while eliminating most of the infrared thermal emission losses, a highly efficient A solar-heated metamaterial capable of rapidly heating to 83 degrees Celsius (181 degrees Fahrenheit) in an open environment with minimal heat loss. Proposed applications for the film include thermal energy harvesting and storage, solar thermal power generation, and seawater desalination.
Our company provides graphene concrete foaming agent, if you need to buy graphene and concrete foaming agent, please feel free to contact us.
Titanium carbide TiC powder is a crystalline solid with gray metallic luster, hard quality, second only to diamond in hardness, and weaker in magnetic properties. For the manufacture of cemented carbide, also used as electrodes and abrasives for arc…
Calcium silicide is used in the manufacture of special metal alloys, for example for phosphorus removal and as a deoxidizer. Calcium silicide is used in the manufacture of special metal alloys, for example for phosphorus removal and as a deoxidizer.…
Niobium carbide (NBC and Nb2C) is a very hard refractory ceramic material, widely used in refractory high temperature materials and cemented carbide additives.…