Alkali-Free Accelerator for Rapid Concrete Setting

• Customization: Available
• CAS No.: N/a
• Formula: N/a
• Model NO.: Alkali-Free Accelerator
• EINECS: N/a
• Appearance: Powder
• Usage: Concrete Additive
• Color: White
• Product Color: Grayish Brown or off-White
• pH Value: 3.0±0.5
• Alkali Content: ≤1%
• Chloride Ion Content: <0.05%
• Safety Rating: Non-Flammable
• Recommended Temp Range: 5°C to 35°C
• Shelf Life: 12 Months in Original Sealed Container
• Application Process: Wet-Mix Shotcrete
• Initial Setting Time: Adjustable 3-5 Minutes
• 1h Strength: ≥8MPa
• MOQ: 1 Ton
• Lead Time: in Stock
• Shipping Methods: EXW/Fob/CIF/CFR
• Sample Policy: 500g Free Sample,Buyer Pays Shipping Fee
• Transport Package: 25kg/Bag
• Specification: alkali-free accelerator
• Trademark: XZH
• Origin: China
• HS Code: 3824409000
• Production Capacity: 50000 Tons Per Year
• Package Size: 45.00cm * 50.00cm * 70.00cm
• Package Gross Weight: 25.100kg
• Lead Time: 7 days (1 - 25 kg) ; 10 days (26 - 50 kg) ; 15 days (51 - 100 kg) ; To be negotiated ( > 100 kg)

Product Description

Alkali-free accelerator 

Alkali-free accelerator is a cutting-edge alkali-free accelerating admixture designed to enhance early strength development and reduce setting time in shotcrete and concrete applications.  Formulated with advanced chemical technology, it ensures safer handling, improved durability, and superior performance compared to traditional alkaline accelerators.

An alkali-free accelerator is a high-performance admixture used to accelerate the setting and early strength development of concrete and shotcrete, particularly in tunneling, mining, and repair applications. Unlike traditional alkaline accelerators (e.g., sodium or potassium silicate-based), alkali-free formulations eliminate the risk of alkali-silica reaction (ASR), which can cause long-term durability issues such as cracking and reduced structural integrity.

Key Advantages of Alkali-Free Accelerators:
(1) Improved Durability – By avoiding high alkali content, these accelerators prevent ASR and corrosion of reinforcement steel, ensuring longer service life.
(2) Enhanced Safety – Non-caustic and low-toxicity properties make them safer for workers and environmentally friendly.
(3) Better Workability – They reduce rebound in shotcrete applications and improve cohesion, leading to higher-quality sprayed concrete.
(4) Compatibility with Modern Cement Blends – Suitable for use with Portland cement and supplementary cementitious materials (SCMs) like fly ash and slag.

Applications

Tunnel lining and underground support

Slope Stabilization & Rock Bolting

Alkali-free accelerators are essential for sprayed concrete (shotcrete) in tunnel construction, providing immediate ground support and stabilizing excavations. They enable:
Rapid setting of primary linings to prevent rockfall and soil collapse.
High early strength development (e.g., ≥8 MPa within 1 hour), allowing faster advance rates in mechanized tunneling (TBM) and drill-and-blast methods.
Reduced rebound compared to alkaline accelerators, improving material efficiency.

In geotechnical engineering, alkali-free accelerators enhance slope reinforcement and rock anchoring by:
Accelerating the hardening of shotcrete layers on unstable slopes, preventing erosion and landslides.
Supporting rock bolting and mesh-reinforced shotcrete by ensuring quick load-bearing capacity.
Minimizing long-term degradation risks (e.g., ASR) in aggressive environments (e.g., high humidity, freeze-thaw cycles).

Rapid Repair of Concrete Structures

 Precast Elements Requiring Fast Demolding

For emergency repairs and infrastructure rehabilitation, alkali-free accelerators offer:
Fast-setting mortars and patching materials for bridges, dams, and pavements, reducing downtime.
Strong adhesion to existing substrates without alkali-induced cracking.
Compatibility with fiber-reinforced concrete for crack-resistant repairs.

In precast production, alkali-free accelerators optimize efficiency by:
Shortening demolding time (e.g., from 24 hours to <6 hours), increasing mold turnover.
Maintaining dimensional stability in thin-walled elements (e.g., façade panels, pipes).
Avoiding surface efflorescence or discoloration caused by alkaline alternatives.

Main performance

The compounding of alkali-free accelerator is simple and convenient. Just add water and stir at room temperature to produce a liquid accelerator, which is convenient for on-site use.

It dissolves quickly. At room temperature with a rotational speed of around 600, dissolution can be completed within one hour.

It has high economic efficiency. Compared with liquid accelerator products, it saves packaging and transportation costs.

It has a good early strength effect, and the compressive strength at 1 day and 28 days can both meet the construction requirements.

It has excellent anti-freezing effect and can be prepared immediately upon use, avoiding the drawback of poor anti-freezing performance of liquid accelerators.

Technical specification

Color	grayish-brown or off-white Powder
PH value	3.0±0.5
Alkali content	1%
Chloride ion content	<0.05%
Package	25kg/bag

Alkali-free accelerator powder can be mixed with water at room temperature in proportion to form a liquid accelerator.
When compounding, a plastic material reaction vessel with stirring function can be used for compounding. Alternatively, a ton drum combined with a mixer can be used for flexible compounding.

(1) It is recommended that the weight ratio of instant powder to water be 1:1. Dissolve it as a liquid alkali-free accelerator for use. According to the characteristics of cement and the different requirements of customers for setting time and dosage, the proportion of instant powder can be adjusted

It varies between 50% and 60%.

(2 )The rotational speed of the stirring blade should be above 600 revolutions per minute, the water temperature should be above 10℃, the dissolution time should be 0.5-1 hour, and the power of the agitator should be greater than 5KW.

The dosage of the accelerator after being mixed into a liquid finished product varies with the temperature of the concrete and the environment, as well as the adaptability of the cement. The dosage for Portland cement or ordinary Portland cement is between 6% and 9%.

The accelerator is pumped and mixed with concrete at the nozzle. This product has a certain viscosity. Therefore, it is recommended to remove the filter screen installed on the rubber hose of the accelerator pump to prevent the accelerator from not being sucked out normally.

Before using this product, please be sure to clean the accelerator pump. It is strictly prohibited to mix this product with other accelerators to prevent chemical reactions between the two accelerators and clog the accelerator pump.

Payment Options

Payment Options – Flexible & Secure for Global Trade

To support smooth international transactions and meet our clients' diverse preferences, we offer a range of trusted and secure
payment methods:
 1. Telegraphic Transfer (T/T)
 2. Letter of Credit (L/C)
* Irrevocable L/C at sight accepted for large-volume orders
* Ensures payment security for both buyer and seller
* Issued via your local bank to our designated bank
 Note: All transactions are conducted under strict anti-fraud and compliance guidelines. We are happy to recommend the most suitable payment method based on your country, order amount, and credit terms.

Transportation

Ocean Freight

Air Freight

Land Transport

Advantages: Cost-effective; ideal for large-volume, heavy, or bulky goods.
Disadvantages: Longer transit time (typically 15–60 days).
Modes:
* FCL (Full Container Load): Full container used by one shipper; suitable for high-volume cargo.
* LCL (Less than Container Load): Shared container space for smaller shipments.
* RORO (Roll-on/Roll-off): For wheeled or self-propelled cargo such as vehicles and machinery.
Common Cargo: Machinery, large furniture, ores, electronics.

Advantages: Fast (usually 1–5 days); ideal for high-value or time-sensitive cargo.
Disadvantages: Expensive and limited cargo capacity.
Modes:

* Freighter Aircraft: Dedicated cargo planes for bulk air shipments.
* Passenger Belly Cargo: Uses spare space in passenger aircraft.

Common Cargo: Electronics, perishables, urgent samples.

Advantages: Flexible and ideal for regional or short-haul transport; integrates well with sea or air freight.
Disadvantages: Limited by geography and border formalities for international routes.
Modes:
* Trucking: Door-to-door service for domestic or cross-border shipments.
* Rail Freight: High volume and cost-effective; good middle ground between sea and air.
* Example: China-Europe Railway Express for containerized trade between Asia and Europe.
Common Cargo: Consumer goods, auto parts, construction materials.

FAQ

 FAQ – International Shipping for Chemical Products

Q1: What types of chemical products do you ship?
A:
We export a wide range of chemical products including:
* Industrial chemicals (e.g., solvents, additives, intermediates) * Agrochemicals (e.g., pesticides, fertilizers)
* Specialty chemicals (e.g., dyes, surfactants)
* Hazardous materials (DG cargo) classified under IMDG, IATA, or ADR
Please share your product's technical data sheet (TDS/MSDS) for confirmation.
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Q2: Can you ship hazardous/dangerous goods?
A:
Yes. We are licensed to export hazardous chemicals and comply with international regulations such as:
* IMDG Code (for sea freight)
* IATA DGR (for air freight)
We can handle UN certification, dangerous goods declaration, labeling, and packing in accordance with the cargo class (e.g., Class
3 flammable liquids, Class 8 corrosives).
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Q3: What documents are required for chemical exports?
A:
Typical shipping documents include:
* MSDS (Material Safety Data Sheet)
* Certificate of Analysis (COA)
* Packing List & Commercial Invoice
* UN Certificate / Dangerous Goods Declaration (if DG)
* Certificate of Origin (COO)
* Customs clearance documents (CIQ, REACH, etc. as required)
We also support customer-requested documents such as Form E, FTA certificates, or embassy legalization.
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Q4: Do you provide special packaging for chemicals?
A:
Yes. Based on the product's nature and regulatory class, we offer:
* UN-approved drums, IBC tanks, HDPE bottles, or custom containers
* Ventilation and corrosion-resistant inner liners
* Labeling compliant with GHS / DOT / IMDG
Packaging meets international transport standards for chemical safety.
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 FAQ – International Shipping for Chemical Products

Q5: Which shipping methods are suitable for chemical products?
A:
Depends on product type and urgency:
* Ocean Freight: Most common for large volumes (bulk chemicals, containers)
* Air Freight: For urgent or small-batch shipments; must meet IATA DGR compliance
* Rail Freight: Ideal for inland routes to Europe (e.g., via China–Europe Railway)
* Multimodal: For DG cargo with restricted port access
We always ensure the method is approved and certified for the product category.
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Q6: How is chemical cargo classified and labeled?
A:
Chemical cargo is classified according to UN Dangerous Goods Codes, and we label accordingly using:
* UN number and hazard class (e.g., UN 1993 Class 3 Flammable Liquid)
* GHS pictograms and precautionary statements
* Shipping marks (as per IMDG/IATA guidelines)
We ensure full compliance with local and international labeling standards.
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 Q7: Do you provide samples? How are they shipped?
A:
Yes, samples can be provided upon request.
* Non-DG samples: Usually sent via courier (FedEx/DHL)
* DG samples: Shipped via certified air/sea freight with DG handling documents
Please confirm your customs and import regulations before shipment.
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Q8: What Incoterms and payment terms do you offer?
A:
We support:
* EXW, FOB, CFR, CIF, DAP, depending on the destination country
* Payment terms: T/T, L/C, or Online payment
For regular customers, we can negotiate flexible payment options.
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Q9: Do you offer after-sales or technical support?
A:
Yes. Our technical team provides support on:
* Product application guidance
* Compliance consulting (MSDS, labeling)
* Logistic issue resolution
We aim for long-term cooperation, not just one-time deals.