PRELIMINARY AND FINAL DESIGN PROPOSAL-PHASE 2, 3 & 4
Scope of Services, Tasks, and Fee
Structural Engineering Services
Rehabilitation of the Pedestrian Walkway on the Pan Am Railroad Bridge, Nashua, NH
July 31, 2020
scope of Services
Summary of Services:
Following is a summary of the professional engineering services required for Preliminary Design
(Phase 2), 99% Design (Phase 3), and Final Design (Phase 4). Note that conceptual design
(Phase 1} has been submitted to the City: -
1) Preliminary and Final Structural Engineering Design and Detailing of rehabilitation
alternatives jor the pedestrian walkway cantilevered off the side of the Pan Am Railroad
bridge in Nashua, NH.
The anticipated schedule is as follows:
August 2020: Contract Executed/Notice-to-Proceed
December 2020: Preliminary Plans and Estimate for review
March 2021: 90% Plans, Specifications and Estimate for review
May 2021: Final Design Documents
April 2021: Project Advertisement
es ¢# 8 8 &
Phase 2 — Preliminary Pedestrian Walkway Design and Estimate
1. Address comments on Conceptual (Phase 1} recommendations.
2. Coordination with the Pan Am Railroad regarding railroad right of way, service life of the railroad
ties supporting the pedesirian walkway, etc.
3. Perform a hands-on evaluation of the pedestrian walkway (this includes the full length of the
cantilevered timber ties) using a rail-mounied under-bridge inspection vehicle and obtain
measurements necessary to complete an analysis and evaluation of the walkway members to
remain. VHB will coordinate with the Railroad to obtain permission to access the tracks and
bridge for inspection purposes.
4. VHB will periorm preliminary design and detailing for the pedestrian walkway components
including the cantilevered timber ties supporting the walkway, the walkway timber stringers,
walkway deck, and walkway railing. The walkway will be designed in accordance with the 2018
American Railway Engineering and Maintenance-of-Way Association (AREMA) Manual.
5. VHB will evaluate and provide up to four railing alternatives for the railing on the west side of the
pedestrian walkway. The chain link fence (CLF) on the east side of the walkway will remain
unchanged.
VHB will evaluate decking alternatives for the pedestrian walkway.
VHB will develop preliminary rehabilitation plans for the pedestrian walkway showing all the major
elements of the walkway but will not include fully developed details of all work elements. This
phase will also identify the proposed railing and decking alternate including material type.
8. VHB will develop a construction cost estimate based on major item quantities and NHDOT
average unit bid prices.
9. The VHB Project Manager / Program Lead will perform a quality assurance review of the
preliminary plans and estimate.
10. VHB will prepare and submit preliminary plans and estimate for review.
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Phase 3 - 90% Pedestrian Walkway Design and Estimate
1. Address comments on Preliminary (Phase 2) recommendations.
2. Final Coordination with the Pan Am Railroad.
3. VHB will perform final design and detailing jor all pedestrian walkway components.
