Expertise

Our expertise includes all aspects of ground engineering as it may be utilised to overcome geotechnical challenges to create new infrastructure and buildings of the future. Our objective is to provide technical excellence for our clients adding value to projects in whatever field of ground engineering which may be required.

DEEP FOUNDATIONS

DEEP FOUNDATIONS
  • Bored piles
  • Driven piles
  • Barrettes
  • Load testing

The selection of deep foundation solution will be influenced by ground conditions, applied loads and site specific constraints such as working space and permitted noise and vibration. Well planned use of load testing (static, dynamic, rapid and/or bi-directional methods) can provide an improved understanding of foundation performance leading to an increased structural utilisation and overall economy.

DEEP EXCAVATIONS

DEEP EXCAVATIONS
  • Sheet pile walls
  • Contiguous pile walls
  • Secant pile walls
  • Diaphragm walls

Programme drivers usually determine whether deep basement construction is built from the bottom up supported by temporary anchors or propping or top down supported by the permanent basement floor slabs. Selection of the preferred embedded walling technique is influenced by site constraints such as working space, ground conditions and required construction tolerances.  

CUT AND COVER TUNNELS

CUT AND COVER TUNNELS
  • Contiguous pile walls
  • Secant pile walls
  • Diaphragm walls
  • Observational method

Cut and cover tunnels frequently form the approaches to major subterranean road and rail crossings. Often constructed in densely populated urban areas, forms of construction are chosen to minimise impact, allowing early construction of roof slabs which can provide running surfaces for traffic and wall designs which minimise adjacent ground movements.

GROUND IMPROVEMENT

GROUND IMPROVEMENT
  • Vibrocompaction
  • Vibro replacement
  • Rigid inclusions
  • Cutter soil mixing
  • Deep soil mixing
  • Trenchmix

The vast range of available ground improvement techniques is constantly developing but each method is suited best to a particular set of ground conditions. Benefits such as minimisation of spoil and reduced construction duration have to weighed up against potential increased risk of foundation settlement. However, pre-start trials and testing can help to increase confidence in overall success.

ANCHORS

ANCHORS
  • Ground anchors
  • Rock anchors
  • Load testing

Whether temporary or permanent, multi strand or monobar, ground and rock anchors often represent critical structural elements supporting water and soil retaining structures on major infrastructure projects and deep basements. Therefore it is essential that high standards of quality are maintained from fabrication, installation, through to testing and stressing and in some cases long term monitoring.

GROUTING

GROUTING
  • Permeation grouting
  • Compaction grouting
  • Fissure grouting
  • Jet grouting

Whereas fissure and permeation grouting techniques are often used to exclude groundwater from excavations, compaction and jet grouting are more commonly used to strengthen the ground. Compensation grouting is used to mitigate the effects of ground movement induced by tunnelling. In very soft grout jet grouting can be used to form sub-formation props to support embedded retaining walls.

CUT OFF WALLS

CUT OFF WALLS
  • Sheet piles
  • Slurry
  • Diaphragm walls
  • Cutter soil mixing
  • Trenchmix

Groundwater cut off walls are installed as part of flood mitigation measures as well as beneath dams to reduce seepage losses. They are also sometimes required to mitigate the effects of migration of contaminated groundwater. Where space allows, they can also be used in combination with battered slopes and dewatering measures to create deep excavations without the need for embedded walls.

GROUNDWATER CONTROL

GROUNDWATER CONTROL
  • Well points
  • Deep wells
  • Pumping tests

Well points are generally used for shallow or multi-stage dewatering schemes often with battered excavations. Deep wells are more commonly used for significant drawdown particularly within a perimeter supported by embedded retaining walls. Pumping tests are frequently used to supplement ground investigation data to assist in the design of wells, predict likely drawdown and estimate discharge.