Sulfate-Resistant Cement (CRS) in Morocco

Sulfate-resistant cement: essential in aggressive environments

Sulfate-resistant cement, designated CRS (Ciment Résistant aux Sulfates) or SR class per EN 197-1, is a Portland cement formulated to durably resist the chemical attack of sulfate ions (SO₄²⁻). These ions, present in certain soils (gypseous, clayey), groundwater, wastewater and seawater, react with the tricalcium aluminate (C3A) of the clinker to form expansive ettringite. This reaction causes internal swelling, cracking and progressive degradation of the concrete. The solution is to limit the clinker C3A content to 5% maximum, which drastically reduces the risk of expansion.

In Morocco, particularly in the Southern regions (Dakhla, Laayoune, Boujdour, Tan-Tan) as well as in coastal and Saharan areas, many soils show high sulfate contents. Using standard CPJ 45 or CPJ 55 cement for deep foundations, sewerage networks or marine structures exposed to these environments almost systematically leads to pathologies within 10-20 years: cracks, spalling, loss of strength. CRS cement, slightly more expensive to purchase (8-12% surcharge), avoids these costly repairs and guarantees a service life of 50 years and more.

Composition and technical characteristics

Dakhla Aménagement CRS cement is a CEM I or CEM II with controlled C3A content ≤ 5%, compliant with Moroccan standard NM 10.1.004 and European standard EN 197-1 (SR class — Sulfate Resistant). Its compressive strength is 45 MPa (CRS 45) or 55 MPa (CRS 55) at 28 days, its initial setting time is greater than 60 minutes (allowing easy placement) and its autoclave soundness is less than 5 mm. Each batch is lab-tested (strength, Blaine fineness ≥ 350 m²/kg, setting time, soundness, C3A chemical analysis) before shipment. Certificates of conformity are available on request.

When to choose CRS over standard cement?

• Sewerage networks and treatment plants (sulfate-rich wastewater)
• Foundations on gypseous, clayey or sulfated soils (analyze soil before choosing)
• Marine structures: ports, breakwaters, quays, bridge piers in tidal zone
• Tunnels and underground structures in sulfated ground
• Agricultural structures: slurry pits, silos, irrigation canals
• Chemical and agri-food industry (floors exposed to sulfates and acids)

Choosing between CRS 45 and CRS 55

The choice between CRS 45 (45 MPa) and CRS 55 (55 MPa) depends on the mechanical load of the structure, regardless of sulfate resistance. For a sewerage network or a pit, CRS 45 is largely sufficient. For a marine bridge pier, a port raft or a heavily loaded deep foundation, CRS 55 will provide the additional mechanical strength. Our technical team can guide you — contact us via the quote form. To compare with our standard cements, see our CPJ 45 and CPJ 55 pages.

CRS cement price and availability

CRS cement is sold from 1,650 DH/T in bulk (tanker truck, minimum 30T), 1,700 DH/T in 50kg bags (1T pallet) and 1,730 DH/T in 1T big bag. Prices are volume-degressive and depend on the delivery zone. As CRS is a specific product, its production is planned to order to ensure freshness and traceability — allow 5 to 10 working days depending on availability. For a custom delivered-to-site price, request a free quote via our dedicated form.