Abstract:
The present invention provides a method of creating a building structure to be installed on a basin floor wherein the base for erecting the structure would be an element of such a block and this block would be placed on the basin floor in such a way, and would be fixed in position relative to it in such a manner, that this base could be used as a foundation for stationary, large-sized heavy structures and also to ensure the possibility of using the block elements as members of the structure being erected and thus to increase the economic efficiency of the method.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims priority of commonly assigned U.S. Provisional Patent Application Ser. No. 61/049,302, filed Apr. 30, 2008, which is incorporated herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to the field of construction, more specifically, to erection of individually located large building structures such as residential buildings, hotel complexes, industrial projects, airdromes, artificial islands etc., on the sea floor in shallow water or in another water basin. 
     BACKGROUND OF THE INVENTION 
     There is a widely known method of creating building structures in water wherein a preset area of a water basin is filled with some inert material to exceed the water level and then a building structure is erected on the surface of the formed island used as a base. 
     However, this method is highly labour-consuming and not economical enough since it requires great quantities of inert material and loading the material on floating facilities and delivering it to a building site. 
     In addition, this method requires the creation of special consolidation to impede landslide and wash-out of the material as well as its sliding down below the water level. 
     There is a known method of creating building structures in water (U.S. Pat. No. 4,511,288), wherein ballastable modules are floated to a preset area of a water basin, then they are submerged in turn, each module is placed on top of a preceding one. Then a structure is erected on a module projecting from water, this module used as a base. 
     The main drawback of such method is the impossibility of using it for erecting stationary, large-sized heavy structures. This is determined by the fact that hollow ballastable modules can neither be used as a foundation for such a structure, nor carry such a foundation. Therefore in practice this method is only used for creating temporary structures intended, for example, for locating drilling rigs, platforms, for receiving aircraft and for locating other structures of this sort. 
     In addition, this method is not economical enough since it requires the use of great quantities of excessive metal (material of ballastable modules) which is of no direct relation to the structure being created. 
     Another drawback is the necessity of connecting the modules with one another under water which complicates the method significantly. 
     And, finally, availability of several modules placed one on top the other affects significantly the reliability of the structure when erected at seismically dangerous areas, at water area subject to heavy sea-ways and also in cases when subsidence of the sea floor is possible. 
     There is a known method of creating building structures in water (EP No. 0199690) wherein a pontoon is floated to a preset area of the water basin, the pontoon height exceeding the water depth in this area. Then the pontoon is submerged and its upper (projecting from water) surface can be used as a base for erecting the structure. 
     Reliability of such a structure in contrast to the one created by the preceding method is considerably higher and, besides, is free of the drawbacks connected with the necessity of implementing under-water work on connecting the modules with each other. However all other drawbacks still exist. 
     There is a known method of creating building structures in water (EP No. 0800600) wherein a pan-shaped block is floated to a preset area of the water basin, this block consisting of a bottom, a deck located above the bottom, and walls hermetically embracing the bottom around its perimeter. Then the block is submerged onto the basin floor by way of filling it with water. The distance between the deck and block bottom is so selected that after the block is submerged onto the bottom, the deck remains above the water level. Then the structure is erected on the deck used as a base. 
     This method, as well as the two preceding ones, cannot be used for creating stationary, large-sized heavy structures since the deck itself can neither be used as a foundation for such structures, nor carry such a foundation. 
     In addition, this method is not economical enough since it requires the use of great quantities of excessive material (under-water portion of the pan-shaped block) which is of no direct relation to the structure being created. 
     There is a known method of creating a building structure wherein piles are first driven into the sea floor. Then a foundation is installed on the piles, and after that the structure is erected. 
     A drawback of this method is its high labour consumption and low economic efficiency determined by necessity of creating a foundation and erecting all the members of the structure in this case the work is implemented from floating facilities, often under water. 
     SUMMARY OF THE INVENTION 
     An object of the invention is the task of finding a method of creating a building structure to be installed on the basin floor wherein the base for erecting the structure would be an element of such a block and this block would be placed on the basin floor in such a way, and would be fixed in position relative to it in such a manner, that this base could be used as a foundation for stationary, large-sized heavy structures and also to ensure the possibility of using the block elements as members of the structure being erected and thus to increase the economic efficiency of the method. 
     The set task is solved in such a way that a prefabricated pan-shaped block is floated to a preset water site where the structure is to be created. The block consists of a base member-a bottom and walls embracing hermetically the base member around its perimeter and forming working area. The depth of water site is less than the height of the block. The block is submerged onto the basin floor by means of filling with water at least a part of the working area, and as a result has the parts located above water level. Then the submerged block is fixed relative the basin floor, the water is removed from the zone where the construction work should be perform and the building structure is erected on the base member. 
     The present invention will be understood more fully from the detailed description given herein below and from the accompanying drawings of the preferred embodiment of the invention which, however, should not be construed as exhaustive to the invention but are for explanation and understanding only. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The essence of the invention is illustrated by drawings which are as follows: 
         FIG. 1  shows the general view of the building structure in water, according to the present invention. 
       FIG.  2 —general view of the floating block, top view. 
       FIG.  3 —section III-III in  FIG. 2 . 
       FIG.  4 —unit A in  FIG. 3 , before dismantling the pipes and concrete placement around the pile head, enlarged. 
       FIG.  5 —unit A in  FIG. 3  after dismantling the pipes and concrete placement around the pile head, enlarged. 
       FIG.  6 - 9 —stages of erecting a building structure, according to the present invention. 
       FIG.  10 —section III-III in  FIG. 2 , another version of the block fixation relative to the basin bottom. 
       FIG.  11 —another version of embodiment of the invention. 
       FIG.  12 —general view of several blocks connected with each other, top view. 
       FIG.  13 —unit B in  FIG. 12 , enlarged. 
       FIG.  14 —section XIV-XIV in  FIG. 13 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The building structure is created in the following way. 
     Reinforced-concrete pan-shaped floating block  1  ( FIG. 1 ) is prefabricated at a factory. Block  1  comprises a base member-a bottom which is essentially one-piece bedplate  2  ( FIG. 2 ,  3 ), walls  3  that embrace hermetically bedplate  2  around its perimeter and internal upright water-tight partitions  4  dividing the working area between walls  3  into individual sections  5 . In one version of embodiment the invention (not shown) partitions  4  are absent. Made in bedplate  2  over its entire area there grooves  6  ( FIG. 4 ,  5 ) with reinforcing bars  7 . Made in grooves  6  are through holes (not shown). In each of these hole branch pipe  8  is concreted with flange  9  located in groove  6 . Upright process pipes  10  are connected with branch pipes  8  by means of flanges  9 . Height “H” of the block ( FIG. 6-9 ), in particular of walls  3 , partitions  4  and process pipes  10  exceeds the water depth “h” at water site  23  where building structure  15  ( FIG. 1 ) is to be erected. Dimensions and configuration of bedplate  2  and walls  3  as well as the dimensions, configuration and place of installation of the partitions are so selected that the maximum number of these elements could be used as the members of the structure erected. 
     Block  1  ( FIG. 3 ) is floated to preset site  23  ( FIG. 6 ) of the water basin where the structure is to be erected. Then block  1  is secured to basin floor  11  by means of anchors  12  through ropes  13  to provide a required orientation of the block. After that those of the sections  5  where the erection of the structure is not planned at the first stage are filled with water by any of known methods. In so doing the number of sections  5  to be filled with water should be such that under the weight of water, block  1  would submerge and rest on basin floor  11 , with bedplate  2  on the basin floor ( FIG. 7 ). Then free spaces  18  between basin floor  11  and bedplate  2  filled up with filler material, e.g. concrete or inert aggregates through openings  24 . 
     In one version of the realization of the method of the block submergence can be provided by filling one part of the sections  5  with water and another part—with inert material with a high specific weight, say, with sand. It is expedient that this inert material could be used as building material in erecting the structure. 
     In one more version submergence can be provided by filling every single section  5 . 
     To increase reliability of block  1  fixation against its possible displacement relative to basin floor  11  and also against its possible further submergence into the ground, piles  14  ( FIG. 8 ) through pipes  10  ( FIG. 4 ,  5 ) are installed into the ground by any of known methods. After that pipes  10  are dismantled and the grooves with the pile heads are concreted (made one-piece with the bottom). Then water is pumped from the block. 
     In one version the increase of reliability of block  1  fixation against its possible displacement relative to basin floor  11  is achieved not with the aid of process pipes  10  and piles  14 . In this version walls  3  ( FIG. 10 ) are prefabricated at a factory in such a way that they extend below the level of bedplate  2  location around its entire perimeter. When such a block is submerged onto the basin floor closed cavity  16  is formed between basin floor  11  and bedplate  2 . Creation of one or several closed cavities  16  is possible not around the entire perimeter of bedplate  2  but under its individual sections. This is achieved by making closed projections on the bedplate, say, circular-shaped ones (not shown) on its side facing the basin floor. Reliable fixation of block  1  against possible displacements is achieved in this case by pumping water from closed cavity to engender vacuum in it. 
     In one more version related to the use of piles  14  ( FIG. 11 ) block  1  may be submerged not to a full depth. In this case bedplate  2  is located on said piles with gap (           ) relative to basin floor  11 .
     Erection of structure  15  is started in sections not filled with water (in the case, when such sections exist).  FIG. 9  shows the parts of the said erected structure—columns of the skeleton  25  and the floors  26 . After the weight of the structure erected exceeds the value of the buoyancy force acting on the block, water is pumped from the sections and the structure erection is completed. Ropes  13  can be removed at any moment after a reliable fixation of the structure erected or being erected relative to the basin floor has been ensured. 
     In one version of embodiment of the invention the lower parts of piles  14  are fixed in addition in the ground so as they are restrained from the displacement upward caused, for example, by the buoyancy force of water, Such fixation can be performed by one of the known methods, for example, by means of anchoring parts of the pile having a thicker cross-section in the bottom part ( FIG. 8 ,  9 ). 
     In one more version of embodiment of the invention, erection of structure  15  after filling entire block  1  or part of its sections  5  with water is started only on the block portion projecting from water (not shown). In this version, similar to the one described above, after the weight of the structure erected has reached the value exceeding that of the buoyancy force acting on the block, water is pumped from the sections and the structure erection is completed. 
     In another version, through holes are made over the entire area of bedplate  2 , may be installed communication pipes  17  ( FIG. 2 ,  3 ). These pipes are similar to afore-described process pipes  10 . The use of communication pipes allows additionally to conduct, if necessary, various activities in the ground, e.g. drilling, geological survey and others. 
     If it is necessary to create building structures with the area larger to such a degree that one block does not allow to solve this problem, several similar blocks are used which are jointed with each other. In this case blocks  1  ( FIG. 12-14 ) are taken which have projections  19  with seals  20  on walls  3  of each of them. These projections located on the external sides of walls  3  and are of such shapes, that they can form together with projections  19  of adjacent blocks, cavities  21  with reinforcing bars  22 , these cavities closed below the water level. First of all the first block is submerged onto basin floor  11  and fixed in position. Then the next block is submerged, brought to the first block so that, when butt-jointed, the blocks form said cavities  21 . Temporary fixation of blocks  1  relative to one another is implemented by means of well-known appliances. After that water is pumped out from cavities  21  with a speed exceeding the speed of water entering through seals  20 . As a result of this pressure P 1  on the walls from the cavity side sharply decreases and blocks  1  become tightly pressed against each other due to the pressure P 2  of water. Then cavities  21  are concreted. 
     Various versions of realizing the proposed method within the claims are possible differing from those described above by the absence of partitions  4  in prefabricated block  1  or, on the contrary, by the availability in it of additional, differently oriented partitions which can be used as members of the structure erected, and also differing from the afore-described in elements and units and materials ensuring the implementation of this or that operation, method, in a technique of connecting the blocks with each other, etc. 
     The proposed method is highly economical since it allows to fabricate at factories, i.e. with minimum labour consumption, floatable blocks with the maximum number of elements (bedplates, upright and horizontal partitions, strengthening ribs, beams, tunnels for running communications, etc.) which are the members of the structures being erected. In this case the floating block is a means of transporting said pre-erected elements of the structures to a preset area of a water basin and at the same time is a zero cycle of construction of planned structures. 
     This method can be used for creating stationary, large-sized heavy structures practically of any dimensions and with no limitation to the weight, since a foundation of these structures are represented by monolythic concrete plates, resting on the basin floor and fixed reliably against displacement and submergence into the ground. 
     Although the invention has been described and illustrated with a certain degree of particularity, it is understood that the present disclosure has only been made by way of example, and that various modifications thereof may be resorted to by those skilled in the art without departing from the spirit and scope of the invention, as hereinafter claimed.