Chargement…
Chargement…
Rapid-set cement (prompt cement, flash mortar) hardens in 5 to 15 minutes, compared to 28 days for standard Portland cement. Essential for emergency repairs, element sealing and leak plugging. Dakhla Aménagement (DAM) supplies the three main families of rapid-set cements in Morocco . Free quote within 24h.
Prompt cement partners in Europe
Setting time tested in laboratory for each batch
5kg, 25kg bags, big bag — delivery included in Dakhla City only
Type choice, dosage, application: support
Rapid-set cement — also called prompt cement, flash cement or fast-hardening cement — is a special hydraulic binder formulated to start setting in a few minutes (5 to 15 min) and reach usable mechanical strength in less than an hour. This performance is achieved through three levers: (1) a special chemical composition — clinker rich in tricalcium aluminate (C₃A), regulating calcium sulfates dosed for flash setting, sometimes accelerating additives (calcium chloride, calcium nitrate, formates); (2) a very high fineness (Blaine > 500 m²/kg) that increases contact surface and accelerates hydration; (3) for natural prompt cement, a specific firing at 1,200 °C that produces a particular clinker (Vicat prompt cement, invented in 1817 by Louis Vicat).
Rapid-set cement contrasts with standard Portland cement in its setting time (5-15 min vs. 45 min-2h) and hardening time (30 min-24h vs. 28 days). This speed is valuable for emergency interventions: repairing a broken step in heavy traffic, sealing a barrier without blocking the site for 28 days, plugging a leak under pressure. In return, rapid-set cement has often more modest final strength (except aluminous cement), releases a lot of heat of hydration, and its working time is very short — it is not suitable for large volume pours. For structural repairs, R3 or R4 repair mortars (EN 1504-3 standard) are preferred, combining rapid setting and high final strength.
There are three main families of rapid-set cements, adapted to different uses. Natural prompt cement (5-10 min) is ideal for flash plugging and sealing. Aluminous cement (2-6h) is preferred for structural repairs and refractory concrete. Ready-to-mix repair mortars (10-30 min) combine ease of use and high strength.
| Type | Setting | Hardening | Strength | Use |
|---|---|---|---|---|
| Natural prompt cement | 5-10 min | 30 min | 5 MPa at 1h | Leak plugging, sealing, emergency connections. |
| Aluminous cement (fused) | 2-6 h | 24 h | 40 MPa at 24h | Structural repairs, refractory concrete, cold weather. |
| R3-R4 repair mortar | 10-30 min | 1 h | 20 MPa at 1h | Concrete refacing, thresholds, steps, curbs, connections. |
Emergency repairs, sealing, plugging: rapid-set cement is the tool of the troubleshooter and the time-pressed professional.
Refacing steps, thresholds, curbs, concrete connections with immediate return to service.
Sealing posts, grids, barriers, railings, anchors without waiting.
Plugging active leaks (pipes, manholes, buried walls) under low pressure.
Underwater repairs, cold weather work: rapid hardening prevents leaching.
Rapid-set cement is a technical product whose price varies greatly depending on the type, quality and packaging. Natural prompt cement costs about 15-25 DH/kg in 5 kg bags, 12-18 DH/kg in 25 kg bags. Aluminous (fused) cement starts at 8-12 DH/kg. R3-R4 ready-to-mix repair mortars are sold at 20-40 DH/kg in 5-25 kg bags. In 1T big bag on order, the price drops to 8,000-15,000 DH/T depending on the formulation. For an exact price, contact specialized distributors. Our grey CPJ 45 is priced by personalized quote, delivered to Dakhla sites. (Market indications — DAM does not sell rapid-set cement.)
To be clear: Dakhla Aménagement does not sell this product and does not import any. Our Lassargua plant (Dakhla) produces only composite grey Portland cement — CPJ 45 and CPJ 55 (CPJ 35 on request) — delivered within Dakhla, delivery included (48h standard, 24h urgent). If your works require rapid-set cement (urgent repair, sealing), contact specialized distributors; our team remains available for all your grey cement needs.
Standard Portland cement (CPJ 45, CPJ 55) begins setting between 45 minutes and 2 hours after mixing, and reaches its final strength at 28 days. Rapid-set cement (or prompt cement) begins setting in 5 to 15 minutes and hardens in 30 minutes to 1 hour, with a usable strength at 1-3 hours (5-15 MPa). This speed makes it possible to immediately immobilize repaired structures, seal elements without waiting, or plug leaks under pressure. Rapid-set cement is not suitable for large volumes (high heat of hydration) — it is used for spot repairs and sealing.
Depending on the formulation, there are: (1) natural prompt cement — setting in 5-10 min, hardening in 30 min, strength 5 MPa at 1h; (2) aluminous cement (fused) — setting in 2-6h, hardening in 24h, strength 40 MPa at 24h; (3) rapid-set repair mortars (ready to mix) — setting in 10-30 min, strength 20 MPa at 1h. The choice depends on the urgency and the expected final strength. For an active leak under pressure, a "flash" cement (setting in 60-90 seconds) is used.
Rapid-set cement is recommended for: (1) emergency concrete repair (refacing steps, curbs, thresholds) with immediate return to service; (2) sealing elements (barriers, railings, posts, grids) without waiting 28 days; (3) plugging active leaks and infiltrations (pipes, manholes, buried walls); (4) underwater work or cold weather (rapid hardening prevents leaching); (5) pipe connections and pipe joints; (6) quick blocking of rebar awaiting concreting. To avoid for large volumes (heat of hydration).
Rapid-set cement is a technical product more expensive than standard Portland cement, due to its special formulation (special clinker, regulating sulfates, accelerating additives). Expect about 15 to 30 DH/kg in 5-25 kg bags depending on quality and speed (natural prompt cement, repair mortar, "flash" cement). In 1T big bag on order, the price drops to 8,000-15,000 DH/T. Ready-to-mix repair mortars are sold at 20-40 DH/kg. For an exact price, contact specialized distributors. Our grey CPJ 45 is priced by personalized quote, delivered to Dakhla sites.
Applying rapid-set cement requires speed and precision: (1) prepare the surface (cleaning, clearing the area) before mixing — once the cement is mixed, you only have 5-10 min; (2) mix in small quantities (1-2 kg at a time) to avoid setting in the bucket; (3) use cold water in hot weather to slightly slow setting; (4) apply immediately and pack firmly; (5) for active leaks, wait until the flow decreases then apply under pressure; (6) cure as soon as setting ends (prompt cement releases a lot of heat). Wear gloves: rapid-set cement is very alkaline and irritating.
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ReadOur production: CPJ 45 on request and CPJ 55 on request, delivered to Dakhla sites (delivery included, 48h/24h). Free quote within 24h.