Xbloc calculator

Delta Marine Consultants has developed an online Xbloc calculator for concept design. Using this calculator will result in the minimum required theoretical Xbloc size. A concept design report is available with your input and output of the online calculator.

Use Xbloc calculator


Xbloc is a concrete armour unit for breakwaters and shore protections. Xbloc is a reliable armour block which has been applied successfully around the world since 2004 in over 30 projects (see section Projects for more information).

Xblocs are stable and robust

Xbloc is made of non-reinforced concrete. The block has a highly robust shape which leads to low tensile stresses inside the block and enable the Xbloc to cope with large forces. The blocks placed together in the armour layer cooperate to withstand wave forces. This is called interlocking. Due to the efficient interlocking of the Xbloc shape, the armour layer has a high hydraulic stability. This means that a small Xbloc can withstand large waves.

Xblocs are practical

The Xbloc is very practical in the various activities during the construction phase. The block has a wide, stable base which allows for efficient storage, handling and transport of the units. Blocks can be stored in multiple layers. The Xblocs can be transported by barge or truck in a vertical position which simplifies the loading and offloading process. Due to the symmetrical block shape, less requirements apply with regard to the placement pattern compared to other single layer blocks. This results in a simplified placement procedure and reduced construction time. 

Xblocs are economic

The block is applied in a single layer whereas many armour layers are made of two layers of blocks. This results in direct savings as a result of the reduced concrete quantities, there are however also significant savings due to the reduced construction time.

DMC Support

DMC offers assistance throughout the various phases in a project.

Latest news

4 June 2018

Introduction of the new XblocPlus

DMC has developed a new armour block which is called the XblocPlus. This block is based on the experiences during 15 years of Xbloc projects around the world. XblocPlus is a single layer concrete armour unit which is placed in a regular pattern: all the blocks on the slope have the same orientation, similar to roof tiles. This simplifies the placement process and it simplifies the approval process.


23 May 2018

DMC signs 2 new Xbloc projects in Turkey and Saudi Arabia: big numbers and big blocks

DMC signed a license agreement for the use of Xbloc on the King Salman International Complex for Maritime Industries and Services Project in Saudi Arabia. This project comprises the construction of breakwaters and shore protections which will be protected by 180,000 Xblocs in sizes of 1.8 and 2.4 tons.