A pedestrian bridge provides a safe mode of passage for pedestrians and enriches the surrounding. Pedestrian bridges can help link two spaces. They are also helpful to bridge areas separated by different water bodies or roads, or structures. They give easy access to such separated rooms. It becomes easy for the passengers on foot or maybe cycles without disturbing the flow of vehicular traffic on main streets and other spaces. Over the years, many architects and engineers have designed such bridges with beautiful aesthetic sense. While designing a pedestrian bridge, one should take a few considerations, such as :
1. Site Analysis
At the beginning of the design process, it is essential to do a detailed site analysis before beginning the process. The study of the site’s climate, Wind direction, sun path, and the site’s surroundings should be studied and analysed. The population density of and around the area should also be calculated to understand an average footfall that is there on the bridge. This helps in further processes, like in the selection of material, and helps in the core designing process.
The measurements of the bridge are generally given in requirements by the patent. But if this is not the case, then hydraulic analysis or geometric features are determined to calculate the bridge’s length. The bridge’s width is calculated depending on the flow of vehicles, their sizes, and the footfall of the passengers that will take place. Looking at the form and size of elements that will pass underneath the bridge, the height is determined.
The primary function of a pedestrian bridge is to allow people to pass over the obstacles safely. This kind of bridge enables the people to use them to touch, feel, and sense the bridge’s surroundings, as mainly the users are on foot. The routes with delightful views can enhance the experience of the user. Such bridges also help in connecting the two spaces with the shortest route.
While designing a pedestrian bridge, it is essential to study the user requirement on an individual basis. The bridge should not only offer easy connectivity, but it should also be user friendly. For example, the bridge design should be in such a fashion that even a person in a wheelchair can use it. Moreover, the bridge’s creation should be in such a way that it gets up with the neighbouring spaces and fits well in the urban planning factors.
The selection of material is a very crucial step in any design process. In the case of such a bridge, the materials which suffice the needs and load-bearing aspects should be chosen. The material should sustain and resist different loads such as wind load, live or dead loads, and thermal expansion. With this, it should also be aesthetically pleasing.
Generally, concrete and steel are used for arches, as the high strength concrete gives a slick and reduced cross-section surface area while also sufficing the load-bearing needs. Today there are many new materials such as high strength steel cables or glass or even stone and many more.
While designing pedestrian bridges, different kinds of loads should be considered. Along with dead and live loads acting on the bridge, many other loads should also be considered. Such as the load caused by the people walking on it, which is called the pedestrian load.
The load is caused by the vehicular movement of the vehicle, the wind load, and many others. The design of the structure should be done after considering these factors.
7. Thermal expansion
When there is a temperature change, the size and shape volume of the material changes. This should be properly studied before calculating the size and shape of the structure. This will reduce the risk of failure of the system due to this phenomenon.
The pedestrian bridges cross various designs and various other elements. Hence it is essential to check the clearance. The clearance gauge measurements tell us about any obstacles in the clearance spaces. This also defines the route and can affect the load on the pedestrian bridge that is being designed. So one should consider this.
Studying the proper loading system to avoid failure is the primary safety factor to be considered. Railings should be provided along the bridge to prevent any mishap.
Depending on the primary material used, the finishing of the structure is taken into consideration. It can fulfil the aesthetical purpose and can be used to protect the primary system from decaying, rusting, or any other damage. The more commonly used methods of finishing are polishing, galvanising, and painting.
Designing is a long, intimate process, which requires a good amount of study and hard work. One can construct a beautiful and functional pedestrian bridge, considering a few factors, as mentioned above.