Baugruben - Komplettlösungen aus einer Hand von Keller Grundbau
Baugruben - Komplettlösungen aus einer Hand von Keller Grundbau

Excavation pits solutions

Complete package solutions

Each project and the local situation requires customised solutions for design and execution of excavation pits.

Our strength is the execution of complex special geotechnical works using our own developed processes. Please ask for more information!

  • excavation pits with various support systems
  • excavation pits with complex underpinnings
  • excavation pits for the mitigation of environmental damage
Excavation pits

Design and solutions

Excavation pits planing
  1. Soil Conditions: difficult soil conditions (stratigraphy, obstructions, existing slopes etc.) require careful design and an appropriate selection of the solution.
  2. Groundwater: protection of the groundwater against pollution and prevention of water ingress into the excavation pits.
  3. Plot boundaries: neighbouring plots and existing rights of way require particular care when designing the support structure and the construction sequence.
  4. Existing buildings: adjacent buildings shall not be damaged by the works. Particularly the serviceability of the existing foundations shall not be compromised, which often requires additional support and underpinning to secure them.
  5. Underground services: Underground services such as sewage and water pipes, power lines and communication cables shall remain in service, especially in densely populated areas such as city centres.
  6. Traffic: Traffic flow should be hampered as little as possible and existing traffic infrastructure needs to be protected against damage.
  7. Varying excavation depths: Some projects require excavation depths to vary across the site. Therefore, a range of solutions are required.
Excavation pits with protection of the existing building structure
Excavation pits with protection of the existing building structure

General requirements on excavation pit

For design and realisation of excavation pits, complex boundary conditions and special requirements are to be taken into account, especially concerning the permanent increase in demands for usable spaces.



  • minimum impact on the existing structures
  • no disturbance to running operations 
  • optimal use of plots and rooms
  • integration of the foundation system in the building structure
  • minimal deflections even for deep excavation pits
  • conformity to environmental standards
  • Resource-saving execution, monitoring, controlling and documentation
  • close cooperation between the designer and special foundation contractor
Solutions and processes
Excavation pits solutions
  1. Excavation support systems Retaining walls: sheet pile walls, Soilcrete® wall jet grouting /underpinning, diaphragm wall, Berlin type pit lining timber wall, bored piles, shotcrete, combinations (e.g. bored piles and Soilcrete® jet grouting), TSM (Tubular Soil Mixing)/DSM (Deep Soil Mixing) with inserted steel beams
  2. Excavation pit wall support: anchors, soil nails, internal steel struts
  3. Excavation pit bottoms Sealing slabs: jet grouting (Soilcrete®), soft gel chemical grouting grout sealing barrier, underwater concerete concrete slab
  4. Uplift tension: bored piles, micro piles
  5. Protection of existing buildings: Soilcrete® jet grouting underpinnings, jet grouting, Soilfrac® fans
  6. Monitoring: supervision, controlling, documentation

Build on our strengths

Keller offers flexible solutions and special techniques to solve even highly complex excavation pit situations. It is an integral part of our company philosophy to work to industry leading quality and environmental standards.



  • packaged solutions for excavation pits including own developed methods and equipment
  • optimized solutions combining several techniques
  • construction of complex underpinning as part of the excavation
  • low vibration and resource efficient construction
  • use of environmentally friendly materials
  • continuous monitoring
  • competent and flexible response when unexpected problems are encountered
  • customer friendly, fast and direct communication between the client and Keller
  • more than 150 years of experience in foundation engineering and special geotechnical work
Excavation pits with close neighbouring buildings
Excavation pits with close neighbouring buildings
Excavation pits within industrial plants
Excavation pits within industrial plants