Driscoll Bridge Rehabilitation Project

Owner : NJTA

Customer : Conti Construction Cornell and Company

Location : Perth Amboy, NJ

Services : Construction survey, Structural design

Awards : ACEC Distinguished Award

Project Summary :

This project, completed in spring of 2009, is valued at 105 million dollars. Nearly 80 million vehicles use the Driscoll Bridge, spanning the Raritan River in Middlesex County, each year. The project involved replacement of the existing concrete deck in stages, and repair of existing stringers, floor beams and girders. There are 26 spans on the bridge, ranging from 80 to 250 feet long.

Garden State received distinguished award from ACEC and was responsible for:


  • Demolition of the existing structural deck while placing cranes, loaders and trucks on the existing bridge
  • Investigation of existing steel structure for all loadings throughout all phases of construction. We also recommended where to place crane outriggers, design the system, and how to distribute the loads over more structure members in order to support all construction loads
  • Design of a new innovative shield system—suspended off the existing bridge structure and that is capable of supporting 150 psf live load, small equipment, man lifts, etc
  • Detailed analysis and design of the jacking system for maximum jacking load of 700 kips. Since the old tie beams between the piers were not capable of supporting such a jacking load, we designed collar frames capable of supporting all loads.
  • Design of new pedestals to be subjected to temporary and permanent loads.
  • Preparation of erection plans and calculations.
  • Complete surveying services throughout all phases of the project such as horizontal and vertical control, as-built surveys of existing structures, and construction layout.