ASPIRE 2013, 3 Part Series. Craig Finley, P.E. contributor
As owners look to save costs and erect bridges faster with less interference to the traveling public, the concepts of sliding and rolling bridges transversely into place after constructing them nearby are becoming more popular. These techniques offer benefits, but they require unique considerations that can make the difference between success and failure. Both design and construction teams must understand these movement considerations.
Sliding or rolling bridges into place has become accepted by contractors due to the tighter time restrictions owners are placing on projects and their awareness of user costs for tying up either roadway access or waterways. These approaches also can help minimize environmental impact during and after construction.
In some cases, owners require this delivery method in their contract documents, necessitating designers and contractors to become familiar with the techniques as soon as they can. In these cases, clients often want to avoid employing cranes on small sites, which create economic drawbacks. On the plus side, owners don’t typically provide detailed requirements for how the bridge should be moved into place. When they do, they often allow contractors to propose alternatives, ensuring the most efficient approach can be employed. Read more…