Technical Article

摘要

The topographical data are-fundamental to the block design development and verification processes and need to be as accurate as possible before the design calculations begin. For existing track, this information can be obtained prior to the development of the initial block design using data from a previous or new instrument survey. For new lines or for existing lines where the track geometry is expected to change, the locations and extents of grades, curves, switch points, and station platforms, as provided to the block designer, must be maintained during the construction phase. Failure to keep the topography consistent throughout the life of the project may well result in significant changes to the block design, which cascade to project schedule delays and cost overruns due to rework - impacts that escalate as project work progresses.