Concrete Mix Design

FLXMAT Engineering takes reference to International Standards to select the concrete mix design for each mattress.  Standards used are dependent on the country of manufacture and the International Standards followed by the supplier’s concrete batch plant.

The standard concrete density used during the manufacture of FLXMAT range between 2300-2400 kg/m3. Higher density concrete is available on request.

Rope Selection

FLXMAT concrete mattresses have a minimum of 4 (four) ropes cast into each concrete block to give better integrity for lifting and to increase the life-span of the mattress.

The rope diameter and Minimum Break Load (MBL) is selected by FLXMAT Engineering to exceed DNV-OS-H205 Lifting Operations (VMO Standards Part 2-5). Designed to a high nominal safety factor and dynamic amplification factor, FLXMAT rope ensures safe lifting in accordance with the required standards and the local conditions.

Mattress Recovery & De-Commissioning

The secret to effective mattress recovery is the quality and quantity of ropes provided within the mattress at the time of manufacture.

FLXMAT Concrete Mattresses are manufactured with 4 (four) ropes embedded in each concrete block creating a strong matrix that improves recovery of the mattress from the seabed.  Increasing the MBL of the ropes selected is confirmed by FLXMAT ENGINEERING.