Laser Scanning and Field Survey

A rail line owned by the Southeastern Pennsylvania Transportation Authority (SEPTA) and used for high-speed passenger trains travels through an area known as the Gwynedd Cut in Upper Gwynedd Township, Pennsylvania. SEPTA desired to have a reliable model for future maintenance, both proactive and for repairs, on this line.

Erdman Anthony provided 3D laser scanning (terrestrial-based LiDAR), with support field survey, to develop a digital-terrain model and cross-sectioning plan of the rail line. The survey was referenced to NAD 83, Pennsylvania State Plane Coordinates horizontal datum, and NAVD 88, vertical datum, in survey feet.

To allow for future conventional topographic surveying, a pair of intervisible control points were placed at the top of the cut.

The client received a MicroStation file containing 25-scale planimetric details, along with an InRoads DTM file. Cross sections at 25-foot intervals showed both rail and rock-face features. The final deliverable included a Leica Geosystems database (.imp) file, with all control data, multi-images, modeling information, and survey control points, on DVD.

As part of this project, Erdman Anthony field personnel attended a SEPTA training course on field safety and conducted field operations in accordance with SEPTA guidelines.

Awards

2011 Diamond Honor Award

American Council of Engineering Companies (ACEC) of Pennsylvania

2011 National Recognition Award

American Council of Engineering Companies (ACEC), National