PROJECT EXPERIENCE:
Route 27 Bridge at Route 110
Photogrammetric Bridge Situation Survey
Location: ARLINGTON, VA

Project Background: Subsequent to earlier surveys performed by Rice Associates of the Route 27 Bridge, Route 110 was relocated and realigned near the Pentagon in Arlington. In 2007 the Virginia Department of Transportation (VDOT) initiated a feasibility study focused on upgrading the Route 27 bridge crossing over the realigned Route 110. Recognizing that the existing survey information was more than five years old, VDOT enlisted Rice Associates to conduct a comprehensive Class 1 Bridge Situation Survey of the Route 27 crossing.

Work Performed: Rice Associates established, horizontally, and vertically controlled a total of 45 targeted and / or photo-identifiable points for use in helicopter mapping. Photography was obtained at a nominal negative scale of 1"=60' and all photogrammetric mapping was developed in compliance with National Map Accuracy Standards as outlined in the "Reference Guide Outline," Specifications for Aerial Surveys and Mapping; as published by the U. S. Department of Transportation.

The aerial mapping was supplemented by means of conventional ground surveys including:

• Identifying the existing right-of-way limits.
• Locating and identifying underground utilities including all utilities attached to the bridge.
• Locating deck drainage and assemblies on the bridge.
• Updating the minimum vertical clearance under the Route 27 Bridge, the ramp to and from Pentagon parking and the ramp from Pentagon South parking.
• Locating and identifying all existing features e.g. edges of pavement, edges of paved shoulders, guardrails, curbs and gutters, barriers, medians and their types, etc.
• Providing bearings, stations and elevations along the baseline at centerline of the piers and the face of the back wall at abutments.
• Providing existing bridge top of deck elevations and ties to the Route 27 survey centerline.
• Providing deck slab spot elevations along the bridge centerline, and the face of curbs at the centerline of piers and the face of abutments.

Deliverables included a plan base and bridge site plan in VDOT / MicroStation / GEOPAK format. All survey activities were conducted in accordance with the Virginia Department of Transportation Survey Manual 2002.