Spring is here, and the short break from road work is officially over. Along with the warmer weather comes the need for road repair and, more specifically, repair to bridges that have taken a beating over the potentially harsh winter weather. In honor of that, we’re taking this blog to cover some of the unsung pieces of equipment we’ve seen go out on bridge repair projects and the unique ways they can be applied to accomplish the tasks at hand.
Jack and Slide
Modern bridge projects have begun trending toward the rapid bridge construction model, making sliding a bridge into place a more common sight. Once a new bridge construction is complete, there needs to be a system to move it safely, quickly, and efficiently onto the supports.
A jack-and-slide system has become a popular option to accomplish that task, replacing several of the more traditional methods, because the objects, or a bridge in this case, are being slid into place versus being hoisted using cranes. Whenever crane use is not possible or cost effective sliding the bridge is an excellent option.
The HydraPak synchronous hydraulic pump allows for the controlled movement of objects, featuring a split flow valve system. Letting each cylinder lift at the same pace despite varying weights experienced at different cylinders.
With 10’, 15’, and 19’ 2” track length sections for the object to slide, the only limit to the distance covered by this system is the number of tracks you order. For longer distances or wider bridges, leap-frogging track lengths allow users to cover a nearly infinite distance with the same system.
Since these systems can safely operate without requiring lever hoists, winch lines, or holdbacks, it often makes for a safer and more efficient option.
To see this application in action, check out 536T Railroad Bridge Install with Hydra-Slide Skid System.
Synchronous Lifting System
LGH has two varieties of sync lift systems to make moving an object that needs to stay completely level with multiple lifting points, such as a bridge, a breeze.
For this type of project, however, there is a more robust system that allows anywhere from 8-24 (cylinder) lifting points to be raised or lowered synchronously to within 0.040″. It does this through an onboard computer that monitors and stores data for all connected cylinders, to make adjustments as needed.
This tool is a great option for tilting, leveling, and final positioning a bridge once in place.
When using this system, we highly recommend you utilize an engineer and someone willing to read through and understand the manufacturer’s use and care manual on-site. Ideally, you will also want to employ someone that has used the system on a previous job. Alternatively, the manufacturer may be able to send a professional out to run the system for a fee, significantly cutting down on issues along the way.
You might be wondering why hydraulic rams are on this list. Turns out these powerful cylinders play a critical role not only in lifting defunct bridges off their supports and lowering new bridges into place during rapid construction but also in a range of other applications.
Although hydraulic rams have a long-standing history in bridge installation, their use in bridge repair is not as widely considered. Nonetheless, they are equally valuable in providing a safe and efficient means of performing various tasks. For instance, some of our customers have used hydraulic rams to release pressure on counterweights before swapping them or other mechanical components during bridge repair.
Air tuggers may be a rare sight on bridge jobs, but they can play a pivotal role in lowering a draw bridge at a controlled rate of speed.
While the job may call for an uncommon low-speed winch, you may employ other methods to increase the lifting capacity of a winch while simultaneously lowering the rate of pulling speed.
LGH handled such a situation on a previous job, working on the Congress Parkway Bascule Bridge in Chicago, IL. The customer had been directed to bring in a specific tugger with a low rate of speed and high capacity. Nevertheless, we identified a more efficient and cost-effective solution by leveraging our rental representative’s extensive knowledge and collaborating with our customer and their engineer. As a result, they completed the job on time, safely, and under budget.
Learn more about this project at the following link: Rehabilitating the Congress Parkway.
While there are certainly numerous other functions each of the above-mentioned tools can perform, we invite you to keep some of these ideas in mind for future bridgework.