Proj Overview

Project Overview

The Garden State Parkway Bridge over the Mullica River features 1,230 feet (375 m) precast concrete girders, which are among the longest continuously posttensioned girders used anywhere in the United States. The design choice minimized the number of piers in the water, which reduced the impact on the river ecosystem and enabled all in-river work to be completed within a tight six-month construction window. The pier caps with abutments constructed on prestressed concrete piles protected with articulated concrete block mattresses. This also provided inspection access.

The engineers estimate that the precast concrete design cost $5.1 million less than a comparable steel option. More importantly, it resulted in a high-performance structure. This was proved when Hurricane Sandy devastated the region just one year after the bridge project was complete. The storm destroyed many structures, but all of the precast concrete elements in the Garden State Parkway Bridge survived unharmed, demonstrating the durability and superior performance of precast concrete for bridge construction.

Precast Solution

The use of precast concrete sections and posttensioning allowed the engineers to maximize the span lengths to a full 220 feet (67 m) while reducing the footprint within the waterway. The six-span bridge has seven prestressed concrete spliced girders sitting on pier caps. Each pier cap is supported by three 8 feet (2.4 m) diameter drill shafts that extend over 150 feet (46 m) below the mud line.

 

Awards
2013 Design AwardsDesign Award Honorable Mention: Bridges with Main Span More Than 150 Feet (46 m) Award
Project Team

Engineer

PB, Lawrenceville, N.J.

Contractor

Agate Construction Co., Ocean View, N.J.

Owner

New Jersey Turnpike Authority, Woodbridge, N.J.

Precaster

Precast Systems, Allentown, N.J.

Precast Specialty Engineer

Freyssinet, Sterling, Va.

Key Project Attributes

  • Precast concrete design cost $5.1 million less than a comparable steel option.
  • Resulted in high performance structure
  • Reduced footprint within the waterway
  • Resiliency of precast was important for this structure due to its location

Project/Precast Scope

  • Features 1,230 feet (375 m) of precast concrete
  • Span lengths were maximized to 220 feet (67 m)
  • Three 8 feet (2.4 m) diameter drill shafts that extend over 150 feet (46 m)
  • Seven prestressed concrete spliced girders sitting on pier caps
  • Took six months to be completed