The improvement of ground properties guarantees solid foundations and therefore, stability, durability, and increased success of construction works. Ground improvement also reduces the cost of foundation works.

Ground improvement methods include:

• Soil consolidation techniques such as grouting, jet grouting, vibro-compaction, stone columns, soil mixing;
• Environmental protection such as slurry walls and curtain grout;
• Temporary consolidation such as curtain wall by ground freezing;
• Dewatering;
• Drainage and preloading to consolidate compressive soils.

Cut-off walls are elastic and waterproof structures capable of resisting earthquakes. They retain water in the subsoil, preventing it from migrating and ensuring the watertightness of the structure. Their role can be essential when building in a marine environment.

The use of post-tensioned concrete for large marine and offshore structures is recognised as a proven solution that protects the steel reinforcement against corrosion, thus eliminating cracking, and enhances water and air tightness of the structures, allowing them to withstand heavy wave and ice loading.

Compared to steel solutions, prestressed concrete offers distinct advantages in terms of durability, low maintenance requirements, fatigue resistance, stability and economical aspects.

VSL’s slab-on-grade solution is perfectly suited to marine structures as it is an economical and fast construction method that is ideal for use whenever large areas need to be covered. Port unloading areas are commonly built using these specially designed slabs that sit on the ground.

A range of techniques to handle heavy loads, including lifting, lowering, tilting and sliding, that allow for alternative construction methods compared with standard in-situ or crane. These bespoke techniques are designed to meet each project’s requirements and offer an increased opportunity for creativity, scale and speed of construction.

Offshore and marine structures can be exposed to seismic risks, wind loading and wave-induced vibrations. It is essential to mitigate such vibration phenomena as much as possible in order to protect the structure and its users.

VSL can offer an extensive menu of tailor-made solutions for offshore and marine structures that require efficient damping system.

A monitoring scheme, including the integration of permanent or quasi-permanent sensor systems, which allows the collection and analysis of data to control and anticipate the structural behaviour and stability of an offshore structure, and optimise maintenance and repair interventions.

Offshore and marine structures are exposed to complex environmental conditions, which can lead to structural failure. In order to improve safety and extend the design life of these assets, it is critical to anticipate the possible failures with the right repair and strengthening techniques.