Who doesn’t love road trips, right?
Long journeys, country music, finger food, and great company. All of this becomes even more special when we have long and smooth roadways to go on. Usually, these roads are known as highway bridges.
Let us learn a bit more about these.
What is a highway bridge?
A highway bridge represents a significant road structure designed to go either over or underneath an obstacle such as a road, waterbody, or any form.
A highway bridge is a seamless road structure that is designed a bit differently than the roads. So, a highway bridge is built differently, as they are designed to go OVER or UNDER a given road, waterbody, or structure. Jargon-wise, these structures are known as Obstacles. We come across these highway bridges in our day-to-day life. For instance, we use bridges to travel across the local water bodies, lakes, rivers, or massive drainages.
In this article, we will learn all about highway bridges. It is no hidden fact that highway bridges are made for the accessibility factor of the population. Also, in most cases, these highway bridges do not allow pedestrians but only vehicles. For the same reason, highway bridges are usually not even built with pedestrian walking space. The reason being that these structures are merely constructed to create accessibility for vehicles, like commuter cars, trucks, and vans, to move freely across the obstacle.
The highway bridges are an architectural epitome that civil engineers build. It is an elaborative process that is initiated by planning the design of this highway bridge. But here’s the fact! Not all highway bridges are the same. There can be massive differences in the respective structures based on several factors such as distance to be covered, the width of the bridge, weight load to be handled, and location of the highway bridge, to name a few.
Longest highway bridge in the world?
The longest highway bridge is The Bang Na to Bangpakong Expressway, which runs through Bangkok. The box girder bridge measures 55km long. The highway bridge was opened in February 2000 at the cost of $1bn.
What are highway bridges called? Highway bridges are called overpass, overbridge, flyover in the United Kingdom and some other Commonwealth countries.
Also, designing these highway bridges determines one essential aspect: whether the structure is to be made above the roads or whether it will be built underneath the establishment. Another critical element that we talk about in highway bridge designing is considering budget constraints and material availability. Such an elaborative process this is!
Once the designing and contextual planning are done, we next talk about materials used for such constructions. Highway bridges can be built using several materials. The selection of material could depend on requirements, structure dimensions, suitability, and even budget.
Various materials can build these structures, such as steel, concretes, stones, metal alloys. More so, one can also use Timber in some amounts to create their giant forms. Sounds crazy, right? Furthermore, once the material is picked from the pile, the engineer moves to the structure’s style. This means that these highway bridges are in suspension structures or cable-stayed structures, to name a few. Thus, designing and selection are crucial, and every relevant factor should be considered for the same.
Next, in the context of our topic, we bring forth the information about the type of highway bridges so built. So, majorly it is made in either of two formations. One is the overheads while the other stands being known as tunnels. So, let us discuss these in a quick brief.
So, an overhead highway bridge is built across or on the top of another structure. Whereas, if we talk about the tunnel style of designing, it is usually built underneath an existing structure. An example of this could be tunnel structures that permit a highway to run through natural occurrences like mountains or other roads. If a tunnel is less than about 0.1 miles, it could be an underpass or chutes.
Composite highway bridge design
In the form of a reinforced concrete deck slab on top of several steel girders, composite construction is an efficient and widely-used construction for highway bridges. There are two common forms of the deck-type bridge – multi-girder bridges and ladder deck bridges.
Moving further, let’s talk about another term that is being associated with the highway bridges that are called interchange. When we talk about the construction mechanism, we have a complex system consisting of ramps and roads, known as an interchange. So, what does an interchange do?
An interchange is an instrumental construction piece. The reason is that the interchange helps the vehicles switch different highways, intersecting themselves on the path. The constructive structures that support the car’s change from one highway to another are connector ramps.
Roadways, Bridge Highways, and all of these mechanisms, all of these Constructions are exquisite art and are very well thought of! These are designed with so much planning, budget, and strategy and show their impact in the longer term.
Highway bridge inspection
Now that we have talked about highway bridges and their associated terms let us discuss how to ensure public safety. Highway bridges are made to provide convenience, accessibility, and fast travel to the public. But, if the general public is not entirely safe while using this mode of transit, what is its use, right?
The Highway Bridge inspection committee is responsible for pinpointing and identifying minor issues associated with this construction and ensuring that these issues are taken care of. Suitable repairs are made from time to time.
If good and preventive bridge maintenance measures are being taken since the beginning of the construction, till the time it’s put to use, and from there on, huge costs and replacements could be avoided. But if the potential risks are higher, then the bridge inspectors must consider the situation and document the situation, the data, and the reports comprehensively to recommend whatsoever remedial measures would be required.
Some measures could include reducing the traffic at the bridge or standardizing the vehicle weight, or even temporarily closing the bridge until it is completely repaired and restored to maximum functionality.