Friday, March 29, 2019

Bridge Launching and Other Methods of Construction of Concrete Bridges

Construction of Concrete Bridges
The companies hired to construct large bridges and other large infrastructure usually need
specialized construction systems set in place as well as experienced professionals to ensure a
safe and efficient construction process. The bridge building needs to be done with utmost care
and precision because these projects are often handed to companies in crowded urban areas
or topographically sensitive regions.


There are various bridge building techniques that can be incorporated in the construction of concrete bridges, but a construction company
should offer its services right from the preliminary stage. The techniques used will depend on
the planning and preliminary design of the bridge till the execution of the construction process.


So what are a few of the important techniques that are used in concrete bridge construction?

Concrete Bridge Construction Techniques:


There are several options available when it comes to finalizing the method of construction of a
concrete bridge. Some of them include:

  • Balanced cantilever (cast-in-situ and precast) technique
  • Incremental bridge launching technique
  • Advanced shoring (Movable Scaffold System or MSS) technique
  • Precast span-by-span technique
  • Heavy lifting technique

There are key differences in each construction method, and they all depend on certain
characteristics. These characteristics include environmental factors, the location of the
construction of the bridge, the length of the bridge, and many more. Some major pointers
to cover in each method of concrete bridge construction are as follows:

Technique Cast-in-Situ Technique


This is one of the most widely used bridge building techniques today. It is proven and safe as well as cost effective, making it an ideal choice for construction of
long span concrete bridges.

Incremental Bridge Launching Technique


The incremental bridge launching technique is a highly beneficial method of construction. When done efficiently, this method can
save time, money, space as well as prevent the disruption of surrounding areas. All of this is done while
maintaining easy accessibility and delivering a high quality constructed bridge.


Some of the other advantages of the bridge launching technique are that it requires a smaller assembly zone, improved safety standards for the workers
and the reduction in the cost of transportation. This is a very attractive option to choose as a method
of construction for concrete bridges.

Movable Scaffold System Technique


This method of construction is mainly used in terrain that is difficult to maneuver. It has been
developed for multi span bridges where scaffolding would be very difficult or unfeasible.
This bridge building technique is most suited for spans of 30 to 60m.

Precast Span-by-Span Technique


This is one of the fastest methods of concrete bridge construction. It is mainly used to build
viaducts that have spans of similar length. The precast method has been used mainly for spans
that range anywhere between 25m to 45m.

Heavy Lifting Technique


The heavy lifting technique is a specialized hydraulic cable lifting technique. It has been developed
for exceptionally heavy loads. This method of construction gives a timely and economical solution for
all projects that are based on modular construction methods that involve large, heavy and pre-
fabricated elements. The main uses of the heavy lifting technique are:

1) Lifting and lowering of heavy loads
2) Lifting of bridges
3) Rotating and sliding of bridges