1. Foundations for offshore wind towers
Marissa Blakley
YES Prep Public Schools – East End Campus
Houston, Texas
Dr. Giovanna Biscontin & Dr. Charles Aubeny
Department of Civil Engineering

2. Dr. giovanna biscontin
Associate Professor, Department of Civil Engineering
Bachelors Degree from the University of Padova, Italy
Masters Degree from the University of California, Berkeley
PhD 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.

3. Dr. charles aubeny Associate Professor, Geotechnical Engineering
Bachelors Degree from the University of Arizona
Masters Degree from the University of Colorado at Denver
PhD 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.

4. The research team Madahuri Murali Marissa Blakley Silvia Vital
Francisco Grajales
Ryan Beemer

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

6. Geotechnical engineering
Investigate 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.

7. Importance of Geotechnical engineering
Railway Track Failure due to
Earthquake Loading
Leaning Tower of Pisa Italy
Natural Disasters such as Vaoint Dam in Italy

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

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

10. Common offshore oil-gas systems
Texas A&M University, Department of Civil Engineering

11. Why 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 world’s energy supply in developing countries could come from renewable sources with wind playing a major role in electricity generation.
Sun, 2012

12. Offshore benefits Usher in a new industry and economic development
Support our nation’s goal of energy security
Support the fight against climate change
Stabilize power prices
Eliminates more than 650,000 tons/year of carbon dioxide
Diversification of energy
Wind over water is stronger, more consistent & smoother than wind over land
Less concern regarding noise & visual appeal

13. Wind turbines
One 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.

14. Construction of an offshore wind turbine

15. The research question
How does the monopile’s interaction with the soft clay at the bottom of the ocean affect the stabilization of the wind turbine?

16. Our problem
The 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 Engineering

17. The research goal
Characterize the behavior of soil so that engineers can make smart, sustainable choices when constructing offshore wind farms.

18. T-bar test
Voltage * Calibration Factor = Force

19. T-bar data collection Time(s) Volts -1.49E-08 0.05 4.02E-07 0.1
-1.49E-08
0.05
4.02E-07
0.1
-7.82E-07
0.15
-1.27E-06
0.2
-1.12E-06
0.25
-2.26E-06
0.3
-1.06E06
0.35
-2.98E07
0.4
-1.33E06

20. Mini-shear vane test
Voltage * Calibration Factor = Torque

21. Project summary
Based on the new market of offshore wind energy, we must study the interaction between the wind turbine’s 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.

22. Classroom connections
Student-Constructed Wind Turbines
Soil Strength Simulation
20-gallon aquarium filled with multi-colored sand
Vertical force applied to sand
Students able to see when soil fails
Student-Led Data Collection Using Custom-Built Pressure Gauge
PreCalculus Data and Functional Analysis

23. acknowledgements

24. Special thanks Dr. Giovanna Biscontin Dr. Charles Aubeny Ryan Beemer
Madahuri Murali
Francisco Grajales
Silvia Vital
E3 Team

25. Questions?