Geotechnical

Foundation engineering requires an assessment of the ground conditions and selection of the most appropriate method to transfer the loads into the ground while limiting the impacts on the local environment. We provide complete geotechnical services including site investigation, ground improvement, foundation design, shoring and underpinning, liquefaction assessment, seismic design, materials engineering, testing (soils, rock, concrete, asphalt) and construction inspection.

Slope stability engineering encompasses the assessment of static and dynamic stability of natural and man-made slopes in soil and rock and the development of mitigation measures. Thurber’s expertise includes identification of landslide triggering mechanisms, deterministic and probabilistic landslide hazard assessments, site investigation, field instrumentation, movement monitoring, laboratory testing, debris flows, coastal erosion, earthquake-induced slope movements and design of stabilization works.

Urban developments are expanding into marginal terrain and retaining structures are often used to create more useable space. Thurber’s experience includes site investigations, lateral earth pressures, design parameters for gravity, cantilever and modular block walls, MSE walls, geogrid reinforced slopes, anchored slope mesh, vegetated bag walls, tangent pile walls, sheet piles, shotcrete and anchor systems and field inspection services.

Earthworks projects typically involve the construction of roads, railways, dams, dikes, mines and landfills where geotechnical assessment is crucial to the success of the project. Thurber has extensive experience in terrain assessment, drilling investigations, laboratory testing, slope stability analysis, staged construction and wick drains, ground improvement techniques, field instrumentation and monitoring, erosion control, in-situ permeability testing (AEP), and materials and construction QA/QC.

Terrain analysis involves identifying geological landforms and potential hazards (landslides, rockfall, debris flows, avalanche). It is well suited for conceptual and preliminary planning for linear projects (highways, railways, pipelines and transmission lines) and the identification of borrow/aggregate sources. Terrain hazard maps are often developed to assist in route selection and construction methodology.

Thurber has a long history of involvement with various dam projects including large hydroelectric structures, oil sands tailings impoundments and flood control dams. Our expertise includes site investigation, dam safety reviews, seismic studies, dike rehabilitation, earth dam design, reservoir stability, seepage analyses, laboratory testing, construction inspection and instrumentation monitoring.

The completion of new underground infrastructure in congested urban areas often requires the use of tunnels and trenchless techniques. Detailed investigation of soil, bedrock and groundwater conditions and assessment of relevant engineering properties (geotechnical baseline reports) are necessary for performance prediction and assessment of the construction impact on adjacent structures. Thurber has extensive experience in tunnels and trenchless projects.

Maintaining stability and limiting displacement to acceptable levels is an important part of the geotechnical design. Services offered by Thurber include installation, monitoring and interpretation of data for instruments such as inclinometers, tiltmeters, settlement gauges, vibrating wire piezometers, electro-level settlement profilers, geophones, load and pressure cells, real-time or data-logged acquisition systems and web-based remote monitoring systems.

Areas of development are often exposed to geological hazard events that must be assessed using risk-based engineering tools. Examples of such hazards are earthquakes, landslides, snow avalanches, rockfall, floods, erosion and debris flows. Our work in this field typically includes terrain assessment, investigation, laboratory testing, instrumentation, stability analyses, risk assessment, and design and inspection of remedial measures and stabilization works.

The design of structures which are built on bedrock requires an in-depth knowledge of geology and rock mechanics. Rock mass classification systems along with numerical modelling techniques are often used for design. Thurber has experience with bedrock mapping, core logging, discontinuity mapping, rock slope analyses, rock mass classification systems, rock anchor design, blast vibration monitoring and acid rock drainage assessment.

A laboratory testing program is an integral part of all significant geotechnical investigations. While standard index tests such as Atterberg limits and grain size distributions are performed for routine projects, the design of major structures requires more advanced testing to determine strength and drainage properties. Thurber can provide advanced laboratory testing such as triaxial testing, direct shear testing, permeability testing, consolidation testing and durability testing.