Engineering geology

Lecture one: Relation between geology and engineering science.

Introduction:

Every engineering structure, whether it's a building, bridge or road, is affected by the ground on which it is built. Geology is of fundamental importance when deciding on the location and design of all engineering works, and it is essential that engineers have a basic knowledge of the subject.
Engineering Geology introduces the fundamentals of the discipline and ensures that engineers have a clear understanding of the processes at work, and how they will impact on what is to be built.

Definition and applications:

Engineering Geology- The application of education and experience in geology and other geosciences to solve geological problems posed by civil engineering structures and works.

The terms engineering geology and environmental geology often seem to be used interchangeably. Specifically, environmental geology is the application of engineering geology in the solution of urban problems;

  • In the prediction and mitigation of natural hazards such as earthquakes, landslides, and subsidence; and
  • In solving problems inherent in disposal of dangerous wastes and in reclaiming mined lands.

Scientific discipline concerned with the application of geologic knowledge to engineering problems such as:

  1. Reservoir design and location,
  2. Determination of slope stability for construction purposes, and
  3. Determination of earthquake,
  4. Flood, or
  5. Subsidence danger in areas considered for roads, pipelines, bridges, dams, or other engineering works.

Engineering Geology is the application of the geologic sciences to engineering practice for the purpose of assuring that the geologic factors affecting the location, design, construction, operation and maintenance of engineering works are recognized and adequately provided for.

Engineering geologists investigate and provide geologic and geotechnical recommendations, analysis, and design.

Works completed by engineering geologists include:

  • Geologic hazards,
  • Geotechnical,
  • Material properties,
  • Landslide and slope stability,
  • Erosion,
  • Flooding,
  • Dewatering, and
  • Seismic investigations, etc.

Engineering geologic studies may be performed:

  • for residential, commercial and industrial developments;
  • for governmental and military installations;
  • for public works such as a power plant, wind turbine, transmission line, sewage treatment plant, water treatment plant, pipeline (aqueduct, sewer, outfall), tunnel, trenchless construction, canal, dam, reservoir, building, railroad, transit, highway, bridge, airport and park;
  • for mine and quarryمحجر excavations, mine tailing dam, mine reclamation and mine tunneling;
  • for wetland and habitat restoration programs;
  • for coastal engineering, sand replenishment, bluff or sea cliff stability, harbor, pier and waterfront development;
  • for offshore outfall, drilling platform and sub-sea pipeline, sub-sea cable; and
  • for other types of facilities.

Engineering geologic studies are performed by a geologist or engineering geologist educated, professionally trained and skilled at the recognition and analysis of geologic hazards and adverse geologic conditions. Their overall objective is the protection of life and property against damage and the solution of geologic problems.

Geohazards and adverse geo-conditions

Typical geohazards or other adverse conditions evaluated by an engineering geologist include:

  • fault rupture on seismically active faults;
  • seismic and earthquake hazards (ground shaking, liquefaction, lurching تمايل, lateral spreading, tsunami and seiche events);
  • landslide, mudflow, rockfall, debris flow, and avalanche hazards;
  • unstable slopes and slope stability;
  • erosion;
  • slaking and heave of geologic formations;
  • ground subsidence (such as due to ground water withdrawal, sinkhole collapse, cave collapse, decomposition of organic soils, and tectonic movement);
  • volcanic hazards (volcanic eruptions, hot springs, pyroclastic flows, debris flow, debris avalanche, gas emissions, volcanic earthquakes);
  • non-rippable or marginally rippable rock requiring heavy ripping or blasting;
  • weak and collapsible soils;
  • shallow ground water/seepage; and
  • Other types of geologic constraints.

fault rupture