The present invention relates to a building structure without foundation, with a cantilever and a counterweight.

Cantilever is a structural element, such as a building part, a beam or a surface that protrudes from the base or seat of the system. This element may be rigid or oscillating. The

cantilever is especially used in the bridge construction process. In a building, the cantilever serves either to extend the useful surface of the building outside its base, for example to create a veranda, or just to shade the area or floor below the cantilever.

In some constructions and in order to avoid the structure to tilt towards the cantilever, a counterweight is placed at the opposite part of the structure and keeps the system in stability .

A conventional building with cantilever is depicted in Figure 1. In this design, architects Lorena Franco and Jorge Cheng present a cantilever building that extends outside the base of the building by about a third of the surface of the base.

Static equilibrium of the cantilever is achieved thanks to the strong foundation of the building.

The document GB2547116, the basic figure of which is depicted in Figure 2, shows a building that belongs to the category of tree-buildingswith two or more cantilevers on either side of the support. The problem which is solved through this

invention is to minimize the support base so that the

remaining ground-floor space can be used as a car park. The structure of the building according to this document follows the rules of the tree-building, in which a pedestal with small surface supports several floors with larger surfaces. The loads of one floor which are outside the base are counter balanced by loads of the same floor which are opposite to the first. This means that the loads of the cantilever, for example on the right side of the building, are counterbalanced by loads on the opposite side, which is the left side of the building .

Figure 3 shows the front and two side views of a building which apparently has a large cantilever. However, as is obvious from the three views, the apparent cantilever is based on two columns which in this document form an angle with respect to the horizon. Therefore, only the part of the building protruding outside the two columns, or the "real base" is considered as a cantilever . In this document as well, the cantileveris small.

Document EP0507623 (Figure 4) presents a building based on a column on which is supported a conical element. The conical element supports cantileversin all directions, which are mutually balanced. This building follows as well, the

structural rules of the tree-building. The structure of this building is complex and necessitates a very precise static design and a technically complex execution of the

construction .

The problem which the present invention is called to solve is to support a large cantilever so as to create a pioneering and impressive building that is very simple in design, is

particularly easy to construct and especially does not necessitate foundations.

The object of the present invention is to overcome the above problem by providing a structural system, such as a stand alone building, which consists of a single element comprising a cantilever and a base, which system is characterized by a counterweight mounted on the base. The base, as well as the entire single element, simply nests on the support surface without foundation. The single element is generally rigid, or it can be allowed to make oscillations.

Since the counterweight has the role of counterbalancing large forces on the opposite side of the building, according to the basic embodiment of the present invention, the cantilever surface may be large, for example much larger than the surface of the base. This means that contrary to the buildings of the Figures 2 and 4, a second cantilever is not required opposite to the first and this allows much more freedom to the

architect .

Therefore, an important advantage of the present invention is that the cantilever can be large in size with respect to the surface of the base, i.e. it may be equal to or larger than the base.

The counterweight may be, for example, a tank, water stored in a tank or swimming pool, sand stored in special containers or in bags, soil, which can also be cultivated and create a garden, one or more rocks or other materials with relatively high density.

The structural study of the building is made by a specialized structural engineer based on the dimensions of the building, the weight of the materials used, the future use and the related loads of the building, external factors such as the wind and the seismicity of the area, the ratio between the cantilever and the base, etc. This study follows the rules of structural engineering and is not part of the present

invention.

According to the basic embodiment of the present invention, the building system is a building comprising a single floor. Alternatively, it may have more than one floors.

According to another embodiment of the present invention, the counterweight may be another structural element, such as a similar structural element which is placed on the base but whosecentre of gravity is within the base. Also, the

counterweight may be another part of a building, such as one or more floors in addition to the base floor whose centre of gravity lies within the base.

Preferably and due to the large size and the fact that most buildings are constructed in one place and never displaced, the structure is constructed at the desired point. However, since the static equilibrium of the building is achieved by balancing the cantilever with a counterweight, another important advantage of the present invention is that the building does not require foundation. The absence of

foundations reduces both the cost and the construction time of the building. Also, the whole system can change orientation, can move or even be displaced to another point or another area. Finally, the absence of foundations reduces the nuisance to the environment, because excavations, which are made by heavy earthmoving machinery are not required.

It is understood that the designer and the constructor may add foundations or support the base to the ground in accordance with existing techniques to further enhance the stability of the building or simply to meet the building requirements of building or other regulations in the area or country in which it will be built, but such a foundation or support is not technically necessary. In addition, a further advantage of the present invention is that the structure can be pre-fabricated in a plant and then transported to the desired location.

Also, after initial placement, the structural element can be moved and positioned elsewhere.

If the single structural member is prefabricated, then its placement at the desired point is done in three phases:

In the first phase, the single structural member is

transported and positioned at the desired point by known techniques and machinery, such as one or more cranes, and the cantilever rests on one or more temporary supportingelements . The temporary supporting elements may be metal columns or any other components or materials suitable for carrying large loads .

Also, the crane (s) may temporarily support the single

structural member at the desired point.

Then, in the second phase, the counterweight is placed. In the basic embodiment of the invention the counter-weight is a rock. In this embodiment the rock is transferred and placed at the end of the single structural element opposite the

cantilever .According to another embodiment, the counter-weight is a swimming pool filled with water. In this case, first is constructed the pool and then it is filled with water.

In the third phase the temporary supporting elements, or other means that may have been used are removed and the stability of the building is achieved thanks to the combination of

cantilever and counterbalance.

Also, after its first installation at one specific point, this structure can be easily changed, re-oriented, or even moved to other locations or landscapes. Thus, it enables its users to experience different landscapes, different view-points, different exposures to the wind and various orientations in relation to natural light.

If the single structural element is prefabricated, then high quality construction can be achieved, quality control becomes easier, whilst also economies of scale are feasible. In addition, the nuisance to the natural environment and

surroundings is minimised, as there is no more noisy building activity, which normally involves opening additional roads, excavating, transporting and storing raw materials, creating dust, etc.

This building system can be used, for example, as a home, office space, exhibition space, museum, commercial space or a combination of the above.

In the drawings

Figure 1 is a sectional view of a cantilever building

according to the prior art.

Figure 2 is a perspective view of a building with two

cantilevers, according to the prior art.

Figure 3 illustrates another cantilever building according to the prior art.

Figure 4 illustrates still another cantilever building according to the prior art.

Figure 5 is a sectional view of the structural system

according to the present invention

Figure 6 is a perspective view of the structural system according to the present invention

Figure 7 illustrates the top view of the building system according to the present invention

Figure 8 illustrates a section of the building system

according to another embodiment of the present invention

Figure 9 illustrates a section of the building system

according to another embodiment of the present invention

Figure 10 illustrates a section of the building system according to another embodiment of the present invention

Referring to the drawings and in particular to Figures 5, 6 and 7, the structural system (1) of the present invention is a stand-alone building consisting of a single element with a base (3) and a cantilever (2) in which a counterweight (6) is placed on the base (3) . As base (3) we consider the part of the single structural element which is supported by-, or standing on a fixed surface (15). In the example represented in Figure 7, the surface (2a) of the floor C-D-E-F of the cantilever (2) is larger than the surface (3a) of the base C-D-H-G of the base (3).

In the same exampleof Figure 5, the naturallandscape which has a slope (4) has remained unchanged and at the desired point a structure (5) has been erected, the upper surface of which (15) is a horizontal surface on which the base (3) of the building (1) is sitting. The structure (5) may be made of stones, of reinforced concrete or of other material or combination of materials known in the art.

Alternatively, a part of the natural landscape which is in slope can be flattened according to known techniques and create a horizontal surface . Then, the base (3) of the building will sit on a part of this horizontal surface (15) .

In the above example of construction, it is obvious that the centre of gravity of the single structural element is located approximately in the centre of the building or on the line A- A' . This means that the centre of gravity is outside the base (3) of the building, the end of which is represented by the line B-B' . Consequently, the building in this form is

statically inadequate or unstable. In order to move the centre of gravity (10) of the building into the base (3), a

counterweight (6) is placed at the end of the building which is diametrically opposite to the cantilever (2). This

technique allows the centre of gravity (10) to be displaced into the base (3) above the fixed surface (15) . The

counterweight of the construction example represented in Figures 5 and 6 is a reservoir, for example a swimming pool which may be filled with water.

The exact dimensioning of the building, the calculation of loads and therefore the size, exact location and size of the counterweight are the subject of a structural study made by a specialized structural engineer following known rules and are not part of the present invention.

The construction of this building is done according to the following phases:

In the first phase, the building system (1) is made in situ, or, if it is prefabricated, transported and placed at the desired location. During this phase, the base (3) is mounted on the support surface (15) and the cantilever (2) rests on temporary supporting elements, such as one or more temporary pillars, not shown in the drawings. These pillars may be metallic, reinforced concrete or any other material designed to carry large loads. Alternatively, the cantilever is supported by cables from the crane (or cranes) which, for example, has moved the building to the desired location.

The counterweight (6, 16, 26) is then placed so that the system becomes stable. In the example of Figures 5 and 6 where the water of a swimming pool is used as a counterweight, the tank itself can be the counterweight, but it is considered more advantageous and the building becomes more stable when the tank is filled with water.

In the third phase in which the tank has been filled and consequently the centre of gravity has been moved into the base (3), the temporary support is removed, and the stability of the building is achieved thanks to the combination of cantilever (2) and counterweight (6). Alternatively, the ropes that support the cantilever are removed.

It is obvious that instead of water the designer and/or the constructor can use other material or combination of materials to minimize the possibility of leakage or evaporation of the water, which in combination with other factors such as wind, excessive loading of the cantilever, etc would result in a change in the building's balance. As such material can be used sand, gravel, stones or soil. In the latter case the soil can be cultivated with plants and/or trees.

Figure 8 illustrates another example of construction in which a rock (16) is used as counterweight. The rock (16) is positioned on the base end (3) and transfers the centre of gravity (10) of the building (1) within the base (3), which is above the fixed surface (15). In this way the stability of the building is achieved.

Figure 9 illustrates another embodiment in which the structure (5) on which the base (3) of the system (1) is mounted, is an existing building. A rock (16) is used as a counterweight. The rock (16) is mounted by a crane at the end of the base (3) and transfers the centre of gravity (10) into the base (3) thereby over the fixed surface (15) .

Figure 10 illustrates yet another embodiment in which a second floor (26), which is built on the base (3) of the building (1) , is used as counterweight. The additional floor (26) can be built at the same time as the rest of the building according to known techniquesor can be transported and added later. In this case the construction of the building is carried out following the three manufacturing phases which have been presented elsewhere in the present description.