Underground Structures - Tunnels

The challenge to build underground structures is the phasing of works

Urban infrastructure increasingly depends on underground solutions to manage space constraints, traffic congestion, and environmental impacts. Underground structures, such as metro stations, pedestrian underpasses, utility corridors, and cut-and-cover tunnels, require precise execution, robust waterproofing, and control over ground behavior during all phases of construction. VSL offers integrated services for the construction of underground structures in complex urban and geological environments.

Strategic applications of underground structures

Underground structures are strategic assets in modern cities, enabling efficient use of space while addressing mobility, resilience, and infrastructure capacity challenges.

Underground construction enables the integration of transport, utilities, and pedestrian access without occupying surface land.

These structures play a vital role in flood mitigation, transit system efficiency, and sustainable urban growth.

The construction of underground spaces demands precise control of excavation, structural sequencing, and groundwater behavior.

See more See less

VSL’s Underground Structure construction services

VSL delivers integrated underground structure solutions that combine geotechnical expertise, structural engineering, and controlled construction methods for complex urban and infrastructure projects.

Excavation support and ground stabilization

VSL provides engineering and execution of retaining systems adapted to ground conditions and site constraints.
Techniques include:
• Diaphragm walls
• Secant pile walls
• Jet grouting and soil mixing
• Ground anchors and struts
These systems ensure excavation stability and protect adjacent structures during construction.

Bottom-up and top-down construction methods

VSL delivers both traditional and top-down construction of underground structures.
• Bottom-up method: Sequential excavation followed by slab and wall construction.
• Top-down method: Enables early construction of surface slabs and superstructures while excavation progresses below, ideal for urban environments with limited access.

Waterproofing and structural works

Waterproofing systems and structural concreting are executed to tight tolerances, especially in metro and transport environments. VSL ensures continuity between underground and above-ground works through integrated sequencing and material compatibility.
Structural solutions may include:
• Post-tensioned slabs and beams
• Reinforced concrete retaining walls
• High-performance waterproof membranes

Why Choose VSL for Underground Structure construction services?

  • Proven underground expertise

    VSL has delivered large-scale underground stations, tunnels, and chambers in Asia, the Middle East, and Latin America.

  • Full-service capability

    From excavation support to post-tensioned concrete, VSL integrates civil, geotechnical, and structural works.

  • Execution in constrained sites

    Specialized in high-density urban areas, working adjacent to sensitive buildings and infrastructure.

  • Integrated engineering support

    Design, method planning, and sequencing supported by in-house engineering teams.

FAQs about Underground Structure construction services

These are some of the most common questions we receive. Got another one? Reach out to us!

Key factors include available access, required construction timeline, ground conditions, and impact on surrounding infrastructure. VSL evaluates each site to recommend the most efficient and safe approach.

Yes. VSL offers integrated delivery of excavation support, concrete works, post-tensioning, and waterproofing, all managed by a single project team.

VSL designs dewatering systems, cut-off walls, and waterproofing membranes based on hydrogeological studies and project needs.

See more See less

Planning an underground structure in an urban or geotechnically complex environment?

Contact VSL today to speak with our underground works specialists and explore tailored solutions.