Solutions for problematics in case study and choice of materials

The following, are the problematics presented in the case study and also the choice of materials taking into account the facts presented before and the solutions given.

3.3.1. Stability of slopes and foundations of bridge

The main reason the pedestrian bridge was destructed was because of a landslide due to a big flood in the place where one of the two foundations or columns where placed. This is shown in the next picture, where it can be seen that on the left part of the river, a piece of the river embankment is missing.

Figure 23. Instability of slopes

Then is completely obvious that the foundations and columns of the bridge must be on a place where it will be safer in terms of stability, that’s why, the length of the bridge must be projected on a distance of 15 meters and its foundations will be placed around the following marked points.

Figure 24. Position Piles and Foundations for new pedestrian bridge

3.3.2. Protection of bridge foundation against flood

Also, in the left part of the river, there is a path that implies a possible run water on this direction, then it’s necessary to create a proper protection for this foundation. This will imply that not only the foundation will need to be moved where it was lately but also protected with a structure. In the following picture, is shown how the path marked by rocks, tells that historically, the river reached this section of the zone.

Figure 25. Possible run water path

3.3.3. Manage of working site

First, it’s necessary to define the exact point that will be given to the helicopter to land and unload materials. This activity, will be done on an area very close to one of the possible foundation’s points (around 10 meters). Also, this space mentioned will be the space where it will be storing all materials, this because it needs to be as closer as it can be to the construction site taking into account that it won’t be many constructions machinery or the zone to move the materials is not as proper as it should be to the machinery. In the following pictures, it will be shown the zone for helicopter and also the proper zone for storing the materials of construction site.

Figure 26. Working site and helicopter landing positions

3.3.4. Architectural point of view and choice of materials

Once knowing the properties of Corten Steel and also the fact that the pedestrian bridge will be constructed in this material, it has been decided to start the project for case study in this material. As it was mentioned previously, one of the aims of the case study it’s also to manage the project on an architectural point of view, then it will be proposed to use another material for barriers of pedestrian bridge and occasionally to beautify the structure.

Taking into account the several particularities and challenges of the case study as the weight of materials, facility and assemble of parts, and also the duration of the material, it’s considered that wood properly used fix perfectly for the project.

Wood is one of the most used materials in Italian construction sector for new buildings and refurbishment activities, especially for pavers and coverings. Wood fiber material, which is obtained from woodworking scraps and sawdust, is being used as synthetic material on insulating purposes. Additionally, his material can be considered as more sustainable due to their natural primary raw materials, referring to sustainable constructive solutions, wood has been considered as a natural material with lower environmental impact. Wood was employed

as a structural material in Italy up to the 1920s. Later, with the development of reinforced concrete, its use has fallen. Only after 2008, wood was considered again as a structural material, although its use in Italy is still very limited and concentrated in the north of Italy (OERCO2 -Erasmus+ European Union, s.f.).

As it was explained, wood fiber materials present good properties for sustainability and also resistance from environment. Now, is necessary to choose the specific type of wood that can be used for pedestrian bridge barriers and also many architecture decisions that will be held during the design process.

Glued laminated timber or Glulam material, is a type of wood with load-bearing capacity and low density which means that is easily managed, then, it can be assembled with simple tools, two properties that are perfect for barriers and also for floor, because of the necessity of resistance of loads and also for the fact that lower weights are needed taking into account the conditions of the construction site. Additionally, Glulam wood have advantages in terms of durability, stability, fire resistance and chemical resistance, very important properties in order to avoid many maintenance works. Finally, as wood will be used mainly for architectural design purposes, Glulam is a perfect chose due to the large variety of shapes and small component dimensions with high strength levels that gives architectural and constructional versatility. It’s known that this material is wide used for structural purposes, however, looking into its many advantages of durability, low density and also loadbearing capacity, it is decided to use it for the architectural design parts where it can be needed.

In the following figure, is shown an example of a pedestrian bridge, where the complete structure (structural system, barriers and floor) was constructed with Glulam wood material.

Figure 27. Glulam Beam Pedestrian Bridges (Taken from Custom Park & Leisure Ltd.)