Structural EngineeringProfessor Patricio Lara Ditzel, Civil Engineer
Technical SupervisionProfessor Cristian Palma Valladares, Architect
The design process wasinitiated through the study of a series of highly known wooden structures, where the capacity of deformation of the materials, and the stiffness of its joints, allowedcreating complex shapes which did not need an external structure to support itself. In this case, we insisted on using the gridshell system.
The shape came out as we tried to meet a model that granted both volumetric beauty and great structural capacity.
After this search we found the hyperboloid, which as it is a conic section – geometric definition-, it works by evenly transferring its load through its whole volume. As we appliedatimbered type constructive system, it gives beauty, neatness and lightness to an object with an extraordinarystructural capacity.
As test mode, we placedthe object horizontally, creating a pavilion.Afterwe did this, we noticed that the structure would nothold out, as it would not be able to transmit the forces evenly, needing complementary structures. Subsequently, we decided to go back to the shape that would make up the structure, including the calculation of the vertical elements which give it its shape and height.
There are plenty oftall constructions that use this type of shape; water towers, cooling towers, buildings, columns, among others.
“Appreciating scenic beauty through natural geography is one of the benefits of looking from a tall construction. Formerly, it was common to find watchtowers in the cultivations. This way people guarded them and it made it easier for them to have visual control without having to walk around the entire fields.
The act of guarding the fields made them watch beyond itsborders, which was unnecessary. As one finds oneself in a high position, it allows one to create a 360º panoramic view.” Under this observation, a watchtower is created for Maule River, which at the same time will give an identity to the valley. In the case of this project, the vineyards guard will also be able to watch the Maule’s sunsets.
After defining the shape and use, we reached the moment to establish the dimensions of the tower, the way to carry out the constriction, the design of the joints, and so. The tower is built on2x2 impregnated pine strips attached to each other by a mass produced sheet metal system. This allows there tobe a slight interaction when the sticks collide, without having to drill them and weaken its structure.
The base of the tower consists of a rectangular platform which seeks to be useful as an element of order, through a multipurpose wooden bench. The idea is for this bench to work as a table, seat or gangway. If one follows the lines of the elevations in the land, one will find that there is a slope which separates the land into two levels, which seek to generate different situations. The higher level, seeks to support the tower and being part of the access to the project. On the other hand, the lower one seeks to shelter the user, taking him to a lower level, generating a meeting point next to the designed stove.
The process o construction consists of two stages.
As there was no electricity in the location where the tower is placed, we had to prefabricate all of the pieces. We had to cut, bend and drill 384 sheet metals. Cut square and drill 96 metal tubes for the junctions of the sticks.Fabrication of 12 mobile bases. Preparation of the wood. Fabrication of over one thousand bolts based on 1-meter wires.
After ending the prefabrication process, we take all the pieces to the land to start with the assembly. According to the planning, in plans and 3D models, the assembly should not present difficulties. The entire process should not take over 3 days. When we started the construction we found that the encounters did not fit as designed in the models, and the wood began to warp due to the high temperatures. After a long process, we managed to connect the first metal ring, and take the first step towards the structuring of the tower.
From this moment, none of the subsequent junctions matched perfectly, which made us come out with a solution that allowed us to keep moving forward and being able to structure the tower permanently.We had to loosen the junctions and move them individually so they would fit perfectly. The problem was that as we adjusted the ring, automatically, the inferior ring would loosen up too, so we had to go back one by one, trying to make them fit. We reached the point where we could not continue to install the rings, since the Wood had expanded too much, and it was too hard join all the sticks so we could install the joints. This is why we surrounded the middle of the tower with a strap commonly used to secure the loads of trucks.A belt was adjusted so the tower completely giving this one inches which gave us the possibility to install all the missing junctions and to stiffen the whole structure.
Later, the superior platform was installed, which gave the tower its final structure. Finally, the stove platform was installed and the floor that supports the Guard of Maule was finished.