Engineer. Engineering. Engineering. (in-ja-neer ) A person trained and skilled in any of the various branches of engineering: a civil engineer

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1 Engineer (in-ja-neer ) A person trained and skilled in any of the various branches of engineering: a civil engineer (Random House Webster s College Dictionary, 1991) CE100 Introduction to Civil Geotechnical Lecture 5 Geotechnical is: That branch of civil engineering that deals with soil, rock, and under-ground water i.e. the use of soil and rock as a construction material. the practical application of science and mathematics, as in the design and construction of machines, vehicles, structures, roads, and systems (Random House Webster s College Dictionary, 1991)

2 Statics Foundations Soil Mechanics Strength of materials Geology Issues addressed by geotechnical engineers: Can the soils support the structure? What will the groundwater due in the future and how will that affect the structure? What is the impact of grading, excavation or filling? Are the earth and rock slopes stable? What type of foundations are best suited for the structure? What type of retaining walls if used are required? How will the site respond to an earthquake? Is the site contaminated? How can a contaminated site be remediated? For every project the geotechnical engineer must: Study the geology of the site and how it affects the planned construction Investigate the surface and subsurface geotechnical materials Conduct field and laboratory tests to ascertain the necessary engineering properties of the soil Determine the most economical foundation system compatible with the geotechnical properties of the site and the needs of the structure. Develop appropriate construction procedures. Monitor the progress of construction To complete a geotechnical engineering project one must: Understand the nature of the structural and geotechnical loading Understand the geological setting of the construction site Understand the engineering behavior of the soils that will carry the structural loads Understand the interaction between the soil and rock and the foundation elements.

3 Geotechnical Core & Electives Electives Core CE 353 Geotechnical CE 453 Geotechnical II CE 454 Soil Stabilization & Site Improvement CE 455 Foundation Design CE 456 Seepage Analysis CE Curriculum at KFUPM Required Courses CE 353 Geotechnical Elective Courses CE 453 Geotechnical II CE 454 Soil Stabilization & Site Improvement CE 455 Foundation Design CE 456 Seepage Analysis CE 353 Soil Mechanics will: Focus on understanding the engineering behavior of soils: Strength Deformation This requires an understanding of: The origin of soil The nature of the individual particles that make up a soil The effect of particle grouping (packing) on the engineering properties of soil. The very important effect of water on the engineering properties of soil. An understanding of how stresses are transmitted to and through soil material The effect of the transmitted stresses on the deformation of soil elements, and An understanding of how soil fails under load. Geotechnical Topics Soil Mechanics (some Rock Mechanics) Deep & Shallow Foundations Landslides & Earthquakes Groundwater Soil & Rock as eng. Materials Exploration & Testing Allied w/ Geological

4 Why do you want to be a Civil Engineer? Proficiency in math and science Suggested by a high school counselor Has relative that is an engineer xx xx xx

5 Geotechnical Main Topics in Geotechnical Origin of soil minerals (Geology) Behavior of soil material (Physics, Chemistry, Materials science) Classification of soil Soil Exploration, Investigation Soil/rock mechanics (Mechanics & Hydraulics) Soil treatment / stabilization / improvement Foundation analysis & design Earth Excavations & tunnels. structures, retaining walls, earth dams Soil Classification Geotechnical Enginggring Subjects Sub-surface Exploration Soil Stratification / Characterization Void Detection Ground water table Sallow Foundation Building Parking Lots Highway / Airfields Deep Foundation On Shore / Offshore Piles Piers Stone Columns Earth Structures Dam Abutments Retaining Structures Retaining Walls Sheet Piles Braced Excavations Geotechnical Properties of Difficult Soils Sabkha Sand Soft Clays Expansive Soils Marl Geo-environmental Soil Contamination Landfills and Waste Disposal Soil Dynamics Earth Dynamic Loading on Foundations and Earth Structures Machine Foundation Soil Structure Interaction Dynamic Static Soil Modification and Ground Improvement Geo-synthetic Material

6 Silt Sand Does Geotechnical Engineer works alone? Clay Earthquake Mechanical Construction Maintenance Improvement Stabilization Structural Geotechnical Water & Environmental Basic Sciences Geology Material Sciences Chemistry Mechanics

7 Perfect coring gives perfect information about discrete locations Excavate a slope at this CE site 100 Dr. what Talat are Bader ground conditions? Then we draw - Simplified Geology Surficial deposits Interbedded sandstone and shale Shale Faults Correctly predict actual conditions from the borehole information??

8 Very Large Concentrated Weight Types of Soils & Types of Loading Drilling Rigs: Old and New Large Distributed Weight Low Weight Weak Compressible Strong Example of Design Requirements Some of the design issues: Structure must be supported safely and without excessive settlement. Basement walls must resist lateral earth and water pressures. Construction must not unduly influence adjacent structures (adjacent building should not fall into your excavation!) Types of Foundations Shallow Deep Spread Mat Pile Some of the requirements: Choose and design appropriate systems. Assess relative performance and cost. QV1 Building, St George s Terrace, Perth Shaft Pile

9 Foundation Types Isolated footing Pile group Water Table Retaining Structures Atmospheric pressure = 0 Free water table

10 This is a $13 million tunnel boring? machine (TBM) used for tunneling at a Nevada Test Site. Niigata Earthquake, Japan

11 Why it leaning Damage to Building, Loma Prieta Earthquake (US) Dams Subsurface Conditions A gravity dam is made from concrete or masonry, or sometimes both. It is called a gravity dam because gravity holds it down to the ground CE 100 stopping Dr. Talat Bader the water in the reservoir pushing it over.

12 Thank you Dr. Bader Embankment dams are made mainly from natural materials. The two main types are earthfill dams and rockfill dams. Earthfill dams are made up mostly from compacted earth, while rockfill dams are made up mainly from dumped and compacted rockfill.