Concrete Mats in WWII: “Chocolate Blocks” and D-Day

Concrete block mats have an interesting history. During preparations for D-Day in World War II, interconnected concrete blocks were used at Stokes Bay in Hampshire, England, to help create durable, trafficable access across soft beach conditions.

Known locally as “chocolate blocks” because of their distinctive rectangular pattern, the flexible concrete mats formed part of the embarkation hards used to move tanks, military vehicles and equipment towards landing craft bound for Normandy.

Creating Trafficable Access Across the Beach

Moving heavily loaded military vehicles across sand and shingle presented a significant challenge.

At Stokes Bay, concrete approaches led onto flexible mats of interconnected concrete blocks laid across the beach. The concrete provided a hard, durable surface with improved traction, while the interconnected configuration allowed the matting to follow the underlying beach profile.

This helped create a more stable and trafficable route for tanks and other heavy vehicles across ground that would otherwise be difficult to traverse.

According to Friends of Stokes Bay, the blocks were cast on the beach using concrete sand and shingle. Their distinctive appearance led locals to nickname them “chocolate blocks”.

Sections of this historic concrete matting can still be seen at Stokes Bay today, particularly when tides and storms expose the surviving structures.

An Engineering Principle That Remains Relevant

More than 80 years later, concrete mat systems have evolved considerably, but there is an interesting similarity in the basic engineering principle.

Interconnected concrete units can provide a durable, trafficable surface while accommodating the terrain beneath them.

Modern Australian Concrete Mats systems use contemporary materials, manufacturing and engineering to provide erosion protection, ground stabilisation and access solutions for applications including:

• Causeways and low-water crossings
• Access roads and tracks
• Fire trails
• Beach and shoreline access
• Drainage channels
• Batters and embankments
• Erosion and scour protection
• Civil, coastal and marine infrastructure

Modern systems are engineered for today’s project requirements, but the surviving WWII “chocolate blocks” provide a fascinating historical example of the durability and practicality of interconnected concrete systems over difficult ground.

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