There are 600,000 bridges in the United States. In total, one in nine of the nation’s bridges is rated as structurally deficient, meaning that over two hundred million daily trips are taken across the nation’s structurally deficient bridges in the nation’s 102 largest metropolitan centers.
The problem lies also in the money allocated to repair structurally deficient bridges. The Federal Highway Administration estimates that in order to repair the structurally deficient bridges $20.5 billion would need to be invested annually, while a little more than half that is currently being spent.
Many companies offer a solution for this problem, specializing in bridge repair. Their techniques range from shoring, to a trench box (complete with trench box dimensions), and even temporary pedestrian bridge rentals. Here are some common types of repair from these companies.
Shoring is classified into three classes. These are dependent on their supporting positions or their positions in space. They are raking or inclined shores, flying or horizontal shores, and dead or vertical shores.
In general, shoring is the process of temporarily supporting a building or structure, wherein props (called shores) are used when the structure is being repaired or altered. These supporting structures can then be placed vertically, angled, or horizontally.
One common technique is placing the debris at least two feet away from the trenches. If they were to fall in, it would damage the general excavation.
Trench shoring provides a critical value whenever a trench is being used to the process of supporting a building or structure. Trench shoring involves the use of hydraulic pistons, heavy plywood, or steel I-beams, depending on the trench box dimensions and the material the trench is dug in.
Some hazards when digging a trench and within the trench box dimensions are:
- Atmospheric hazards, such as low oxygen levels or toxic fumes when digging a trench more than four feet deep.
- Tension cracks which are often 50% to 75% of the depth of the trench, forming horizontally.
- Soils. Some soils may be too untenable for a trench and must be approached with caution.
Shoring boxes, shoring equipment, and shoring systems can vary depending on the tool used or the project that is being worked. Trench boxes, for instance, are usually dug in open areas, and may be used with a combination of sloping and benching. The trench box dimensions should extend at least 18 inches above the surrounding area if there is sloping toward the excavation.
It is important to know that the average age of bridges in America is 42 years and that in the future many more of these bridges will be rated as structurally deficient. In that case, it is important to invest more in the repair and alteration of these bridges, by calling on different techniques that these companies use to support the bridge during repair and construction.
Whether through shoring or trench box or trench box dimensions, this critical industry will be needed in the future.