Paved Track Rail Boot Design and Construction in Portland, Oregon

摘要

Tri-Met is nearing completion of the 18-mile Westside LRT Project, which includes a 6-mile segment serving the City of Hillsboro. For the in street section of the trackway in downtown Hillsboro, the contractor submitted an alternative proposal for the track structure. A rubber boot proposal was submitted and accepted by the owner for the in street design portion of the trackway (Figure 1). The design is the only existing rail boot system which is now partly installed and tested with full isolation properties.The track structure houses the rail in an extruded rubber boot which provides full isolation, in accordance with current established electrical isolation criteria, and noise and vibration attenuation. The rail and boot is fastened into a concrete track slab by an elastic spring clip and isolator assembly for holding the rail to elevation and gauge. An infill slab between the rails and on the outside is being constructed with colored concrete and surface profiled. The boot system for a standard LRT system has been developed for this project using materials engineered for full isolation protection, cost efficiency and simplicity of installation. This will have a significant benefit to the project in terms of cost and time schedule, and is considered to be a serious contender for other transit-related rail works.This paper will address the following aspects of the design and implementation of this system:1. Boot extrusion.2. Drainage issues and isolation problems.3. Vibration and noise attenuation.4. Isolation requirements and test results.5. Boot and trackway costs and cost comparisons with other designs.6. Construction installation and presentation.