Off-shore wind energy

Foundations for offshore wind towersMarissa BlakleyYES Prep Public Schools East End CampusHouston, TexasDr. Giovanna Biscontin & Dr. Charles AubenyDepartment of Civil Engineering

Dr. giovanna biscontinAssociate Professor, Department of Civil EngineeringBachelors Degree from the University of Padova, ItalyMasters Degree from the University of California, BerkeleyPhD from the University of California, Berkeley

Research Interests:Dynamic response of soils, earthquake engineering, seismic slope stability, experimental methods for characterization of soil behavior, numerical methods and modeling in geomechanics, soft soils, offshore geotechnics, and deep soil mixing.

https://ceprofs.civil.tamu.edu/gbiscontin/Dr. charles aubenyAssociate Professor, Geotechnical EngineeringBachelors Degree from the University of ArizonaMasters Degree from the University of Colorado at DenverPhD from the Massachusetts Institute of Technology

Research Interests:Foundations and anchors for offshore structures, offshore risers and pipelines, slopes and retaining walls, dams and levees, expansive soils, and numerical methods in geotechnical engineering.

https://ceprofs.civil.tamu.edu/caubeny/The research teamMadahuri MuraliMarissa BlakleySilvia VitalFrancisco GrajalesRyan Beemer

Geotechnical engineeringA branch of civil engineering concerned with the engineering behavior of earth materials that uses principles of soil and rock mechanics

http://en.wikipedia.org/wiki/Geotechnical_engineeringGeotechnical engineeringInvestigate subsurface conditions and materials.Determine the relevant physical, mechanical and chemical properties of these materials.Evaluate stability of natural slopes and man-made soil deposits.Assess risks posed by site conditions.Design earthworks and structure foundations.

http://whatiscivilengineering.csce.ca/geotechnical.htmImportance of Geotechnical engineering

Leaning Tower of Pisa ItalyRailway Track Failure due toEarthquake LoadingNatural Disasters such as Vaoint Dam in ItalyWhy offshore geotechnical engineering?

Population density in 2007Esteban, 2011Why offshore geotechnical engineering?Population density in 2030

Esteban, 2011Common offshore oil-gas systems

Texas A&M University, Department of Civil EngineeringWhy offshore wind energy?With more and more interest in renewable energy sources, countries have begun to look offshore to fulfill energy needs.Currently, wind energy makes up 2% of the global energy supply and is expected to grow by 160% in the next five years.By 2050, 80% of the worlds energy supply in developing countries could come from renewable sources with wind playing a major role in electricity generation.

http://www.treehugger.com/corporate-responsibility/offshore-wind-farms-to-power-15th-of-europe-by-2030.htmlSun, 2012Offshore benefits

Wind turbinesOne 1.8 megawatt wind turbine can produce up to 4.7 million units of electricity per year.

This amount could meet the annual needs of up to 1,000 households.

Construction of an offshore wind turbine

The research questionHow does the monopiles interaction with the soft clay at the bottom of the ocean affect the stabilization of the wind turbine?

Our problemThe strong lateral forces present at sea cause wind turbines to vibrate, or rock back and forth.These vibrations cause the soil at the bottom of the ocean to weaken, creating a vertical angle between the pile and ocean floor.If this angle exceeds 5o, the wind turbine stops producing energy.

Texas A&M University, Department of Civil EngineeringThe research goalCharacterize the behavior of soil so that engineers can make smart, sustainable choices when constructing offshore wind farms.

http://inhabitat.com/T-bar test

Voltage * Calibration Factor = Force

T-bar data collection

Time(s)Volts0-1.49E-080.054.02E-070.1-7.82E-070.15-1.27E-060.2-1.12E-060.25-2.26E-060.3-1.06E060.35-2.98E070.4-1.33E06Mini-shear vane testVoltage * Calibration Factor = Torque

Project summaryBased on the new market of offshore wind energy, we must study the interaction between the wind turbines monopile and the soft clays at the ocean floor. Studying these interactions will allow engineers to make cost-effective and sustainable decisions when installing wind farms in the near future.

Classroom connectionsStudent-Constructed Wind TurbinesSoil Strength Simulation20-gallon aquarium filled with multi-colored sandVertical force applied to sandStudents able to see when soil failsStudent-Led Data Collection Using Custom-Built Pressure GaugePreCalculus Data and Functional Analysis

acknowledgements

Special thanksDr. Giovanna BiscontinDr. Charles AubenyRyan BeemerMadahuri MuraliFrancisco GrajalesSilvia VitalE3 Team

Questions?