Two weeks ago, we finished our third large-scale test. This particular test was designed to replicate a section of the demonstration tower which we are installing later this Spring. The critical section failed at 1.5 times the design strength of the demonstration tower.
Our group just published two new papers — one in Structural Safety on multivariate analysis of wind and wave in the design of offshore wind turbines and another in Renewable Energy on the magnitude and influence of foundation (i.e. soil) damping on the dynamics of offshore wind turbines. You can check them out on my publications page.
Spencer, Sanjay and I have just published a new paper on the variability of breaking wave characteristics and impact loads on offshore wind turbines supported by monopiles. The paper’s conclusions are based on a comprehensive multi-year measurement campaign at the Blyth offshore wind farm off the coast of England.
Ground was broken at MIT’s middleton campus, where Keystone Tower Systems and Northeastern University are installing a 10 kW turbine on a spirally welded tapered tower to demonstrate the viability of this new tower manufacturing process. The anchor cage, which will be embedded in the turbine’s foundation, was just assembled at the STReSS lab (see below) and will ship to site this week.
Last month, we completed our first large-scale test at the STReSS lab — see picture below taken from the overhead crane. The specimen was a spirally welded tube manufactured by Keystone Tower Systems and loaded in pure bending. The hydraulic loading and data acquisition systems both worked perfectly. Next test will be in late October. We are currently adding two laser scanning systems to more accurately characterize imperfections and local buckling. You can read an overview of this project here.
The Department of Energy just announced a $1M grant to Keystone Tower Systems with a subaward to Northeastern. The project will provide a detailed design and certification for a spirally-welded tower supporting a utility-scale wind turbine.
Sanjay, Kai and I have just published a new paper on a method to evaluate the lateral capacity of offshore wind turbines under extreme wind-wave loading.
Vahid’s and my paper on the influence of aerodynamic damping on the seismic response of wind turbines was just published online in the ASCE Journal of Structural Engineering.
Rob Rosa, a 2014 B.S. graduate from UCONN, will be joining the Sustainable Structures Group in early July. Rob will be helping to design and execute our large-scale tests on spirally-welded tubes.