What are Early Strength Agents?

Sweden is in talks with Turkey on joining NATO and looks forward to strengthening cooperation with Turkey in security and counter-terrorism, Swedish Prime Minister Anders Andersson said recently.  

Andersson held a joint press conference with visiting European Council President Michel in Stockholm on the same day. Andersson said Sweden is in dialogue with Turkey on joining the TREATY and looks forward to strengthening bilateral relations with Turkey, including cooperation in the areas of security and counter-terrorism. She said Sweden would study a number of issues raised by Turkey.  

Speaking at a news conference, Mr. Michel said he believed the Swedish government was taking positive action and taking the necessary steps to reach a solution.

Sweden and Finland formally submitted their applications to NATO Secretary-General Jens Stoltenberg a few days ago. According to protocol, NATO must admit new members by the "unanimous consent" of 30 members.

Turkish Foreign Minister Mevlut Cavusoglu said His country would agree to start NATO talks with Sweden and Finland only if they reach written agreements to stop supporting terrorism and lift restrictions on exporting defense equipment to Turkey, Turkish media reported.

Affected by the ever-changing international situation, the supply and prices of international bulk early strength agent are still very uncertain.

What are Early Strength Agents?

Early strength agent is an admixture which accelerates the development of concrete early strength and has no significant effect on later strength. Early strength agent can accelerate the hardening process of concrete under normal temperature and low-temperature load temperature (not less than -5℃), and is used for winter construction and emergency repair projects.

Early Strength Agents Performance

Early strength agent refers to the admixture which can accelerate the development of early strength of concrete. The main mechanism of action is to accelerate the hydration rate of cement, and accelerate the early crystallization and precipitation of hydration products. The main function is to shorten the concrete construction curing period, speed up the construction progress, and improve the template turnover rate. 

Where can Early Strength Agents be Used? 

1. Early strength agent is suitable for steam curing concrete and normal temperature, low temperature and minimum temperature is not less than -5℃ environment construction of early strength requirements of concrete engineering. Early strength agent should not be used in hot environment. 

2.The chemical substances that harm the human body or pollute the environment after mixing concrete shall not be used as early strength agents. Early strength agent containing hexavalent chromium salt, nitrite, and other harmful components is strictly prohibited for drinking water engineering and food contact engineering. Ammonium nitrate shall not be used in office, residential and other construction projects.

Classification of Early Strength Agents 

Early strength agents mainly include inorganic salts (chlorine salts, phosphates) and organic amines, and organic-inorganic compounds.

1. Chloride salts early strength agents

Chlorine salts early strength agent mainly includes calcium chloride, potassium chloride, aluminum chloride and ferric chloride, among which calcium chloride is the most widely used. Calcium chloride is a white powdery substance, and its appropriate dosage is 0.5% ~ 1.0% of the cement quality, which can improve the 3d strength of concrete by 50% ~ 10% and the 7d strength by 20% ~ 40%. Meanwhile, it can reduce the freezing point of water in concrete and prevent concrete from being frozen in the early stage.

Using calcium chloride as early strength agent, the biggest disadvantage of containing Cl- ions, will make steel corrosion, and lead to concrete cracking. In order to inhibit the corrosion effect of calcium chloride on steel bars, calcium chloride and sodium nitrite (NaNO2) are often combined. 

2. Sulfate early strength agents

Sulfate early strength agent, mainly sodium sulfate, calcium thiosulfate, aluminum sulfate, aluminum potassium sulfate, and sodium sulfate is used more. Sodium sulfate is white powdery thing, the general admixture amount is 0.5% ~ 2.0%, when admixture amount is 1% ~ 1.5%, the time that achieves concrete design strength 70% can shorten half or so. 

Sodium sulfate has no corrosion effect on steel bar, and is suitable for concrete which is not allowed to be mixed with chlorine salt. However, due to its action with calcium hydroxide to generate strong alkali NaOH, in order to prevent alkali aggregate reaction, sodium sulfate is strictly prohibited for concrete containing active aggregate, at the same time, attention should be paid to not excessive mixing, so as not to lead to the late expansion of concrete cracking damage, and prevent concrete surface “frost”. 

3. Organic amine early strength agents

Organic amine early strength agents mainly include triethanolamine, triisopropanolamine and so on, among which triethanolamine is the best early strength agent. 

Triethanolamine is a colorless or light-yellow oily liquid, alkaline, and soluble in water. The early strength of concrete can be improved by adding 0.02% ~ 0.05% of cement quality.  Triethanolamine has a slight retarding effect on concrete, and too much of it will cause serious retarding and concrete strength to drop, so the dosage should be strictly controlled.

Concrete Additives Supplier

TRUNNANO is a reliable concrete additives supplier with over 12-year experience in nano-building energy conservation and nanotechnology development.

If you are looking for high-quality concrete early strength agents, please feel free to contact us and send an inquiry. (sales@cabr-concrete.com)

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.

According to Reuters, U.S. Treasury officials said they would discuss with G7 leaders pricing caps and tariffs on Russian oil as an alternative to the embargo, which would keep the market supplied, limit price spikes, and reduce Russian revenues.  

The EU foreign ministers' meeting was held in Brussels.  The meeting failed to agree on the sixth round of sanctions, including an oil embargo on Russia, because of objections from Hungary.  

EU High Representative for Foreign Affairs and Security Policy said at a press conference after the meeting, that the meeting failed to reach an agreement on the final adoption of the sixth round of sanctions, the permanent representatives of member states to the EU will continue to discuss. The foreign ministers faced similar difficulties trying to reach an agreement on an oil ban. He said Hungary's position was based on economic rather than political concerns.  

Hungary is highly dependent on Russia for energy, getting more than 60 percent of its oil and 85 percent of its natural gas from Russia.  

A few days ago, the European Commission submitted the sixth round of proposed sanctions against Russia, including a total ban on Russian oil imports by the end of this year. Hungary immediately objected and said it wanted substantial compensation from the EU to offset its loss from giving up Russian oil.

The early strength agent price is predicted to increase in the next few days, due to geopolitical factors.