Transcript Off-shore wind energy - Texas A&M University

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
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.
https://ceprofs.civil.tamu.edu/gbiscontin/
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.
https://ceprofs.civil.tamu.edu/caubeny/
THE RESEARCH TEAM
Madahuri Murali
Marissa Blakley
Silvia Vital
Francisco Grajales
Ryan Beemer
GEOTECHNICAL ENGINEERING
A 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_engineering
GEOTECHNICAL ENGINEERING
 Investigate subsurface
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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.
IMPORTANCE OF GEOTECHNICAL ENGINEERING
Leaning Tower of Pisa
Italy
Railway Track
Failure due to
Earthquake
Loading
Natural Disasters
such as Vaoint
Dam in Italy
http://whatiscivilengineering.csce.ca/geotechnical.htm
WHY OFFSHORE GEOTECHNICAL ENGINEERING?
POPULATION DENSITY IN 2007
Esteban, 2011
WHY OFFSHORE GEOTECHNICAL ENGINEERING?
POPULATION DENSITY IN 2030
Esteban, 2011
COMMON OFFSHORE OIL-GAS SYSTEMS
Texas A&M University, Department of Civil Engineering
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.
http://www.treehugger.com/corporate-responsibility/offshore-windfarms-to-power-15th-of-europe-by-2030.html
Sun, 2012
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
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.
CONSTRUCTION OF AN OFFSHORE
WIND TURBINE
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?
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
THE RESEARCH GOAL
Characterize 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
Channel 1
0.00E+00
15
5.00E-05
1.00E-04
Voltage (V)
1.50E-04
2.00E-04
2.50E-04
3.00E-04
17
19
21
Time(s)
Volts
0
-1.49E-08
0.05
4.02E-07
0.1
-7.82E-07
27
0.15
-1.27E-06
29
0.2
-1.12E-06
0.25
-2.26E-06
0.3
-1.06E06
33
0.35
-2.98E07
35
0.4
-1.33E06
Time (s)
23
25
31
MINI-SHEAR VANE TEST
Voltage * Calibration Factor = Torque
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 costeffective and sustainable
decisions when installing wind
farms in the near future.
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
ACKNOWLEDGEMENTS
SPECIAL THANKS
Dr. Giovanna Biscontin
Dr. Charles Aubeny
Ryan Beemer
Madahuri Murali
Francisco Grajales
Silvia Vital
E3 Team
QUESTIONS?