Geotechnical Engineering is a section of the MnDOT Office of Materials that deals with the analysis, design and construction of foundations, slopes, retaining structures and other systems that are made of or are supported by soil or rock. Within the Geotechnical Engineering section, there are three units:
- Subsurface investigations, sampling and testing of soil, rock, and groundwater and measurement of in-situ engineering properties for foundations for bridges, retaining walls, high embankments and other structures.
- Design and review recommendations for bearing capacity, settlement, slope stability, and other foundation related problems.
- Design and review for engineered embankments and excavations of soil and rock, retaining walls and reinforced earth systems of all kinds on stable and unstable ground.
- Construction assistance and monitoring of geotechnical related functions such as pile driving (using the Pile Driving Analyzer), slope stability (using slope indicators), and pore water pressure (using piezometers).
- Expertise and training in geosynthetics, lightweight materials, alternate retaining walls/systems, geotechnical instrumentation, steepened slopes, swamp crossings, and failure investigations.
- Technical research liaison for geotechnical issues at local, regional, and national levels.
- Foundations Scoping
- Foundations Baselining
- Lithological identification, rock mass classification and analysis of rock competence for recommendations including: rock slope and excavation design, foundation bearing capacities, blasting, vibrations, and rock fall management.
- Complete subsurface geophysical investigations using electrical resistivity for a variety of transportation infrastructure facilities.
- Evaluation of groundwater problems and design of groundwater control systems; mitigation of dewatering impacts and prevention of moisture damage to pavement structures.
- Guidance in the search for sound, durable aggregates for construction by identification of deleterious properties and recommendations for screening test procedures, and assessment of properties of native materials produced by the aggregate industry.
- Technical recommendations and guidance in the areas of engineering geology, vibrations, water wells, and aggregate quality by: providing training for technical certification; preparing manuals, standards, specifications and special provisions.
Grading and Base
- Technical assistance and training to project personnel in matters related to excavation, embankment, and aggregate base construction items.
- Develop new and/or modify existing specifications. Audit construction projects to ensure compliance with testing rates and specification requirements.
- Conduct and/or aid in research and implementation of research results relative to pavement design and subgrade soils properties/characteristics.
- Aggregate source information and recommendations to district soils, materials, design engineers, and Office of Technical Support personnel.
- Maintain the Aggregate Source Information System (ASIS) computer database for aggregate sources and provide updates for district users, and others as requested.
- Provide technical expertise regarding aggregate durability, availability, and specifications.