Working platforms for wind turbines

The High Sheldon Wind Farm produces wind energy for the Town of Sheldon in Wyoming County, New York. The project has a maximum electric generating capacity of 129 Megawatts and produces enough clean, renewable energy to power 60,000 homes every year. The project consists of 75 wind turbines installed predominantly on active agricultural lands occupying two windswept plateaus. With elevations of up to 550 m, the two plateaus are exposed to consistent winds from Lake Erie, about 50 km to the west. Energy from the project is delivered to a 230 kilovolt (kV) electric transmission line that passes through the project area.

The major challenge facing the contractor was the potential rutting caused by the extremely high live loads on the turbine access roads. In order to support loading from equipment of up to 240 kPa, A Geogrid was installed to enhance the subgrade of the access roads on the site. Basetrac Grid PP 30 was the ideal reinforcement solution for this project because of its exceptional reinforcement and confinement properties. The contractor was pleased with the ease of installation of Basetrac Grid and the greater coverage achieved with the wide rolls.

An added benefit of Basetrac Grid is separation between aggregate materials and subgrade soils. The design of Basetrac geogrid’s apertures creates separation, keeping large base particles from penetrating the softer subgrade soils without losing confinement. In fact, pullout tests confirm that interaction with the aggregate is greater than or equal to products with larger apertures.

Aggregate base course thickness of the access roads was reduced as a result of using a Geogrid, leading to significant savings for the project owner, Invenergy. The 5,20 m width of the rolls added value because fewer overlaps were required than with narrower products, resulting in less waste. With no sharp edges or roll “memory”, installation of Basetrac Grid was smooth and easy. Basetrac geogrid’s high aperture stability resulted in less rutting because deformation of the base coarse was restricted.