Slip and Wear in Multi-Layer Azimuth Track Systems
Many antennas use wheel-on-track systems in which track segments consist of wear plates mounted on base plates. The hardened wear plates are typically connected to the base plates using bolts, and the base plates are supported on grout and anchored to the underlying concrete foundation. For some antennas, slip has been observed between the wear plate and base plate, and between the base plate and the grout, with migration in the wheel rolling direction. In addition, there has been wear at the wear plate/base plate interface. This paper describes the use of finite element models (FEM’s) of the wheel, track, and foundation to understand the behavior of the wheel-on-track system, and to evaluate possible retrofit concepts. The FEM’s are capable of representing friction and slip, and the opening and closing of gaps at the interfaces between the wheel, wear plate, base plate, and grout. The FEM’s can capture the behavior of the components as the wheel rolls forward. The paper also describes a method to estimate the amount of wear at the wear plate/base plate interface based on the relative slip and contact pressure between the wear plate and base plate.
SPIE Astronomical Telescopes + Instrumentation