The completed bridge will include 12 precast concrete arches that rise more than 20 feet above the roadway surface at their highest point. Two of the arches were moved last weekend.
Over the weekend, Sundt moved the first two 300-ton concrete arches that will become part of the reconcstructed West 7th Street Bridge in Fort Worth, Texas. The remaining 10 arches will be moved and set into place, one at one time, between mid-May and mid-June. The $25.9 million bridge construction project involves the replacement of the approximately 100-year-old West 7th Street Bridge with a new signature structure – the world’s first pre-cast network arch bridge. Here’s a short-time lapse video showing one of the arches being moved into place:
Construction of the pre-cast bridge elements – performed by Sundt’s own concrete crews – began in January 2012 at an offsite casting yard. They are being hauled to the project with self-propelled mobile transports and set in place with twin Liebherr 1400 cranes with superlift.
The bridge’s innovative “pre-cast concrete network design” makes it the first of its kind anywhere in the world.
The West 7th Street Bridge boasts an innovative design consisting of 12 lighted, pre-cast, post-tensioned concrete bridge arches that rise more than 20 feet above the roadway surface at their highest point. Each arch measures 163 feet long and weighs 640,000 pounds.
When complete, the bridge will feature four travel lanes with a center raised median to separate traffic. Pedestrians and cyclists will have safer and improved mobility on the reconstructed bridge, which includes separated 10.5-foot pedestrian/bicycle travel ways on the outside of the bridge arches.
The reconstructed West 7th Street Bridge will serve as a landmark gateway connecting the city’s downtown to its Cultural District and the newly renovated Montgomery Plaza area. The project will be complete by Thanksgiving and open to traffic on October 1.
The 1,100-foot-long steel bridge truss was moved last Saturday during a 12-hour operation. It is approximately 25 feet high, weighs about 3,400 tons and had to be moved 33 feet on one end and 66 feet on the other.
If you were anywhere near the Sellwood Bridge in Portland, Ore., last Saturday, you would have seen an amazing sight. A 1,100-foot-section of the existing bridge deck and truss was lifted with hydraulic jacks, moved aside and set onto temporary support piers to make way for construction of a new bridge. The move created what is known as a “shoofly,” or detour bridge, which will keep traffic flowing over the Willamette River as crews build the new structure to take its place.
Reconstruction of the 87-year-old Sellwood Bridge is being performed by Sundt and joint venture partner Slayden Construction. The team’s innovative approach to the project is expected to save about $5 to $10 million in construction costs and cut about a year off the schedule.
Bridge construction is notoriously challenging, but even so, last Saturday’s “bridge slide” was considered a highly complex operation.
“This was one of the longest bridge sections ever to be moved,” said Sundt Area Manager Ted Aadland. “That, plus its age, made it very difficult. The site itself also presents a number of challenges. The project is tightly confined, being sandwiched between the Willamette River, a cemetery and difficult topography. The Slayden/Sundt Joint Venture Team has worked hard to come up with solutions that minimize traffic impacts, and so far I think we’ve been very successful.”
The new West 7th Street Bridge in Fort Worth, Texas will be the only one of its kind in the state.
Developing innovative ways to build complex projects is one of Sundt’s specialties. Case in point: the $24.1 million reconstruction of the West 7th Street Bridge in Fort Worth, Texas, a new landmark gateway between the city’s downtown and new cultural district that will feature two, 10-foot-wide pedestrian walkways and 12 precast concrete and stainless steel arches that run the length of the 980-foot-long structure.
When the first phase of construction begins in January 2012, Sundt will keep the current bridge open and operational while constructing the concrete arches offsite – with its own concrete crews. In the spring of 2013, the precast arches will be placed on both sides of the old bridge at night. Once they’re all in place, the old bridge will be closed and demolished and the new bridge will be built in its place – in just 150 calendar days. Area Manager Chris Cedar calls this phase of the project “tight, but do-able” with lots of manpower and planned overtime shifts. In fact, his aim is to open the new bridge earlier than its scheduled completion date of November 2013.
Using Building Information Modeling, or BIM, will help the team manage the project’s complexities, particularly the construction of the arches, because they contain many structural and lighting elements that have the potential to clash with one another if not planned precisely. BIM is a high-tech replacement for construction drawings on paper. Using multi-dimensional computer models, constructability issues can be identified and resolved before construction begins.
Approximately 300,000 pounds of polished stainless steel within the arches and bridge superstructure will be illuminated at night with embedded lighting, making the West 7th Street Bridge a one-of-a-kind in the state of Texas.
Designed as an open steel deck arch structure, the new Sellwood Bridge will complement its surroundings while providing ample space for all modes of travel.
When you combine Sundt’s size and proven ability to be innovative with the knowledge and experience of a local contractor, you get a project like the $160 million reconstruction of the Sellwood Bridge in Portland, Ore. Sundt and joint venture partner Slayden Construction used Building Information Modeling (BIM) and a sophisticated video presentation to develop and propose a faster, safer and less expensive method for reconstructing the aging bridge than was originally called for in the project’s Environmental Impact Statement. The approach will shorten the project schedule by approximately one year and reduce the cost to the owner, Multnomah County, by $5 to $10 million.
The 86-year-old Sellwood Bridge stretches 2,000 feet across the Willamette River. Rather than rebuilding it in sections and shifting traffic back and forth between the old structure and newly completed segments, the team will create a ”shoofly” (detour) bridge to keep traffic flowing throughout the project. The approach involves lifting the old bridge deck and truss with hydraulic jacks and moving it to one side, then placing it on a set of temporary piers and connecting it to temporary approach spans so that traffic can continue to use it while the new bridge is constructed.
What are the benefits? Creating a detour bridge is safer for construction crews and the public because it frees up the existing alignment for workers and keeps traffic out of the construction zone. By eliminating the need for complicated traffic phasing, it also shortens the project duration and therefore the overall cost. Another benefit is that it allows for a sleeker bridge design with fewer redundant features and fewer in-water impacts, which is better for the river’s ecosystem.
The new Sellwood Bridge will be complete and efficiently transporting motorists, bicyclists and pedestrians across the Willamette River in 2015.