Research Proposal for SOURCE Funding Application for Summer 2008
Project Title: Tensionless Wind Turbine Foundation Design and Environment Assessment
Student: Alex Potter-Weight, Department of Civil Engineering
Faculty Sponsor: Bill X. Yu, Assistant Professor, Department of Civil Engineering, Case
Western Reserve University
Goals and Objectives
Pursue preliminary technical study on tensionless pier for wind turbine foundation design.
Project Description
Background Information
Development of renewable energy such as wind energy has become a priority in the U.S. and
over the world. Wind energy helps reduce the green house gas emission; it contributes to a
secure energy supply by alleviate the dependency on the traditional fuel technology.
Uncover the power of wind energy presents tremendous opportunities in line with great
technical challenges. Cuyahoga county, for example, has initialized a feasibility study
program on the first offshore wind farm in Lake Erie. A number of technical and regulatory
issues need to be addressed to ensure a successful wind energy policy.
Foundation is an important component to ensure the safety of wind tower structure. Wind
turbine foundation needs to satisfy structural criteria and avoid adverse effects on the
environment. Patrick & Henderson (P&H) Tensionless Pier involves the application of posttension stress to prevent tensile stress in piers. It has many advantages in terms of
construction, structure and environment. This type of foundation has demonstrated excellent
performance as wind turbine foundation (Fig. 1). This study is initialized to identify the
technical challenges for applications of this type of foundation in Lake Erie.
Fig. 1 Example photo of tensionless wind turbine foundation construction
Problem to Study
1) To use empirical formulas and computer simulations to study the lateral bearing capacity
mechanism of P&H tensionless pier; 2) To estimate the characteristic foundation vibration
frequency; 3) compare analyses results with field measured data on the lateral foundation
movement and characteristic vibration frequency; develop guidance to prevent the resonant
conditions; 4) To study the interactions of piers with river currents, such as the induced soil
erosion and the release of contaminated sediments..
Urgency and Benefits
The sustainable development of human society relies on a sound strategy for developing
clean energy source. Wind power helps to achieve such a goal. Ensure the structural and
environmental soundness of the wind turbine foundation is crucial for successful exploration
of wind energy.
Methods to Use
1) To conduct a literature survey to identify the common types of wind turbine
foundations and their design criteria;
2) To perform preliminary numerical simulations to evaluate the performance of P&B
tensionless pier under static and dynamic loading conditions, which can include:
a. Analyze field data to determine the static displacement and dynamic
frequencies
b. Construct computational model to evaluate the responses of foundation under
typical design loads;
c. Compare the simulation results and field measurement data to optimize
foundation design and to prevent resonant conditions;
3) To analyze the interaction of lake current with pier structure. Identify the
environmental effects such as soil erosion.
Time Table
It is expected that majority of the work for this research can be accomplished during the
summer. The time table to accomplish the major research activities is listed below.
Depending on availability of funding sources, the faculty sponsor will try to support the
student to continue work part time on the project over the semester.
Time Table to Accomplish the Major Tasks for this Research (some tasks can be conducted
in conjunction with each other).
1) Literature review (2 weeks)
2) Empirical analyses and computer simulation of the static and dynamic responses of
wind turbine foundation; assess the fluid structure interactions (5-6 weeks)
3) Provide recommendations by summarizing the analyses results.
4) Report (1 week)
Educational Plan for the Student
The research topic is of significant importance for construction industry and government
agency. This research will generate seed data to successfully secure funding from these
external sponsors. With such supports, this study can be potentially expanded into a Master’s
thesis.
Budget Summary and Justification
A total amount of $3,500 is requested from the SOURCE program for this project. The
faculty sponsor will provide funding to supplement the cost of project supplies.
Itemized budget:
Student stipend:
Travel:
Project Supplies:
Other (copying and report printing):
$3,500
$1,500
$
Total Budget:
$5,000
Total Amount Requested from SOURCE:
$3,500
Total Amount Requested from other sources:
$1,500
(will be provided by the faculty sponsor and potential industry sources)