Method for the construction and anchorage of a building structure to a foundation

Abstract

 Method for the construction and anchorage of a building structure or the like, preferably a launched and floating building (11 or several building sections, to a foundation. On the construction site there is prepared a foundation whose crown or head portion is located below the draught of the floating building structure (1). The structure (1) is supported against the foundation by means of pillars or legs such that at least the substantial portion of the loads is transmitted by the pillars to the foundation. The foundation is surrounded with a sheet pile wall with an opening through which the building structure is floated in over the foundation, and the opening is closed once the structure has been moved in over the foundation. The building structure is supported against the foundation and the water inside the pile sheet wall is thereafter evacuated.

Description

[0001] The present invention relates to a method for the construction and anchorage of a building structure to a foundation,which structure is a launched and floating structure or consists of several building sections.

[0002] It is known in the art to construct floating buildings or like structures and float them to their destinations where they are anchored. Examples of such buildings are parking buildings, restaurants, marinas and the like, arranged at a quay or a gangway installation, or similar structures anchored at their places of destination.

[0003] The construction of buildings and other structures in shipyards confers a great many advantages. Thus, working efficiency may be kept on a relatively higher level in shipyards where building structures can be erected in an industrially efficient way, as are for instance ships. Further, work in a shipyard is normally better organized and is performed more rationally than on a conventional building site. Another major advantage is that the time for preparatory installation work on the contemplated building site will be reduced and, besides, this work may be performed concurrently with the construction of the building structure proper in the shipyard. It is advantageous, of course, that the installation work progresses rapidly and also that the environment will suffer from a considerably reduced installation work period. This means less transport of heavy material, less noise and less environmental disorder.

[0004] Another important factor in this context is that in areas where heavy-duty buildings are to be erected, there is often a shortage of builders. In rapidly de- volping areas for instance, the constructional work on the building sites is carried out by a commuting labour force to a great extent, which is a most unfortunate solution.

[0005] On the other hand, there is at the moment in most shipyards a large excess labout capacity which may readily be engaged in the construction of floating structures. Furthermore, the tasks of the constructional work may be distributed such that the main body of the building structure which in principle will be in the form of a ship's hull, can be produced in one shipyard and the interior fittings and installations in another.

[0006] A drawback in floating structures, whether they are provided with a stationary land communication or not, is that they will be raised and lowered with varying water level. Moreover, all floating structures are submitted to special regulations of classification and subject to relatively far less favourable terms of insurance.

[0007] It is further known in the art to use buildings or building structures which can be floated to the erection site where axially movable legs are placed against the sea bed, whereupon the building is elevated by a relative movement between the building and the legs. Constructions of this type are utilized to a great extent as drilling platforms or the like in off-shore oil exploitation. Being of a special design, these structures are of course not suitable for dwellings, offices, factories and the like, especially since they are very expensive to produce, difficult and costly to transport and also because the space underneath the building structure proper is not used.

[0008] One major object of the present invention is to profit from the advantages gained in the construction of building structures in shipyards whence they can be floated to their destinations, while at the same time the above- discussed drawbacks are eliminated.

[0009] According to the invention, this object is achieved by a method for the construction and anchorage of a building structure and the like, preferably a launched and floating building structure or several building sections, to a foundation, in which method there is provided on the erection site a foundation whose crown or head portion is loacted below the draught of the floating building structure which is supported against the foundation by means of pillars or legs in such a manner that at least the substantial portion of the loads is transmitted by the pillars to the foundation, characterized by surrounding the foundation with a sheet pile wall provided with an opening through which the building structure is floated in, claosing said opening after the building structure has been floated in over the foundation, supporting the building structure against the foundation and thereafter evacuating the water inside said sheet pile wall.

[0010] In a further development of the invention, the building structure is elevated in that the water level inside the sheet pile wall is raised before the structure is supported against the foundation.

[0011] According to an alternative embodiment of the invention, the method is characterized by elevating the building structure by means of jacks provided with vertical rods which are supported against the foundation, for in= stance pile heads, providing in the bottom of the building structure outwardly open vertical channels (wells) extending up to a level above the water level in the floating state of the building structure, passing the rods of the jacks up through the channels and engaging the jacks in the upper portion of the channels which are solidly anchored in the lower portion of the building structure so that the total supporting load is transmitted to the foundation.

[0012] The invention will be more fully described hereinbelow with reference to the accompanying drawings, in which:

Fig. 1 schematically shows a finally anchored building structure according to the invention;

Fig. 2 shows in sectional view a pile head and the lower portion of the structure;

Fig. 3 is a section taken along the line III-III in Fig. 2, and

Fig. 4 schematically shows, in conformity with Fig. 1, a finally anchored building structure according to the invention.

[0013] Fig. 1 is a schematic section of a building structure constructed and anchored to a foundation according to the method of the present invention. The building structure consists of a sealed and floatable lower part 1. This part is calculated on and constructed as a ship's hull. In the embodiment according to Fig. 1, this part has two storeys which, in the finally anchored state of the building structure, will be at least partially below the water level. The water surface is designated 2. The two storeys must be used for instance as parking areas. Below the lower storey, there are provided trimming tanks 3. The lower floating structure carries a more or less conventional building 4. This building is however of a design which may suitably be produced in a shipyard, i.e. the bearing structure consists of steel on which prefabricated wall sections, window panels, decks etc, are mounted in a per se known fashion.

[0014] Before the building structure is floated in over the erection site, arrangements have already been taken for the provision of a foundation. In a preferred embodiment of the invention, this foundation consists of piles 5. In the embodiment of Fig. 2, the piles are steel pipes. It is of course possible to use other types of piles, for instance concrete piles. The foundation may also of course be given any other suitable design. Thus, where the sea bed is such that piles cannot be driven into it, it is possible to cast a concrete bed. The upper edge portion of the foundation, for instance the pile heads 6, is situated below the draught of the building structure. Fig. 2 shows the position of a building structure which has just been floated in over the foundation. As will be appreciated, the bottom 7 of the bottom section of the building structure is located a small distance above the upper edge of the pile head 6. The head 6 carries a centering ring 7 for a steel rod 8, a so-called jack rod, for a jack 9. Such jacks are generally available on the market and are used for instance in connection with slipforms. The jack rod 8 extends through a channel or guide tube 10 which is open both outwardly and inwardly and extends up to a level above the water level 2 in the floating state of the building structure. The rod 8 thus extends through the bottom of the bottom section of the building structure into the guide tube 10. The tube 10 is solidly connected to the structure so that all prevailing loads are transmitted by this tube to the foundation. In the embodiment shown in Figs. 2 and 3, the tube 10 is connected to robust vertical beams 11 and 12 by connecting plates 13. The vertical beams 11 and 12 together form a solid column which is connected to the bottom 7 of the building structure. The bottom 7 consists of supporting beams 14 and an outer shell 15.

[0015] From the position shown in the sectional view of Fig. 2, the building structure is raised by means of the jacks 9 to an elevated position in which at least the substantial portion of the loads is transmitted by the jack rods 8 to the piles 5. This means that the building structure is elevated with its bottom section to a level about the water surface. The building structure may also, of course, be raised a considerable distance above the water level if this should prove suitable, or the raising of the building structure may be interrupted when the bottom of the bottom section of the structure is at a distance below the water level, i.e. so that a portion of the load is taken up by the buoyancy. The latter alternative may be chosen when the sea bed is unsuitable.

[0016] In Fig. 1, there is not shown any land or shore communication. Normally, however, the building structure is so disposed that there is such a communcation permitting vehicle driving.

[0017] Fig. 4 shows an advantageous embodiment of a building structure according to the invention. Here, the space 16 inwardly of the sheet pile wall 17 is fully exploited. After the structure 1 has been floated into the space 16 inside the wall 17 through an opening (not shown), the water inside the wall 17 is evacuated once the opening or gate has been closed. The building structure may either be anchored to the foundation at the height level which it assumes when floated in over the foundation, or it may be jacked in the above-defined fashion, or water may be pumped into the space inside the sheet pile wall such that the building structure is elevated by the raised water level. Under all circumstances, though, the water is evacuated once the building structure has been supported against the foundation. The space below the bottom 7 of the structure 1 may be used for instance as a cellar, as store rooms or, preferably, parking lots, as is shown in the drawing. The decks 18 may then readily be suspended in the pillars.

Claims

1. Method for the construction and anchorage of a building structure and the like, preferably a launched and floating building structure or several building sections,to a foundation, in which method there is provided on the erection site a foundation whose crown or head portion is located below the draught of the floating building structure which is supported against the foundation by means of pillars (8) or legs in such a manner that at least the substantial portion of the loads is . transmitted by the pillars to the foundation, characterized by surrounding the foundation with a sheet pile wall (17) provided with an opening through which the building structure is floated in, closing said opening after the building structure (1) has been floated in over the foundation, supporting the building structure against the foundation and thereafter evacuating the water located inside said sheet pile.

2. Method as claimed in claim 1, characterized by elevating the building structure (1) in that the water level inside the sheet pile wall is raised before the building structure is supported against the foundation.

3. Method as claimed in claim 1, characterized by elevating the building structure by means of jacks (9) provided with vertical rods (8) which are supported against the foundation, for instance the heads (6) of piles (5) driven into the ground, providing in the bottom (7) of the building structure outwardly open vertical channels (10) (wells) extending up to a level above the water level in the floating state of the building structure, passing the rods (8) of the jacks (9) up through the channels (10), and engaging said jacks in the upper portion of said channels which are solidly anchored in the lower portion of the building structure so that the total supporting load is transmitted to the foundation.

4. Method as claimed in claim 3, characterized by supporting the vertical rods (8) inside the channels to prevent buckling of the rods.

5. Method as claimed in claim 3, characterized by fixing the vertical rods (8) at the top portions of the channels (10), for instance by welding, and thereafter relieving and removing the jacks (9).

6. Method as claimed in claim 5, characterized by disposing a spacer between the bottom (7) of the building structure and the pile heads (6) and thereafter relieving and removing the jacks.

7. Method as claimed in one or more of the preceding claims, characterized by disposing trimming tanks (3) in the bottom section of the building structure, and trimming said structure as it is lowered onto the foundation.

Drawing