Abstract:
A support system for an equipment item on a concrete slab includes at least one raised block relative to the slab and of a single piece with the slab. The block includes a metal belt delimiting the vertical walls of the block and a metal support fastened to the belt and capping the block to receive a foot of the equipment item.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to PCT/EP2013/058216 filed Apr. 19,2013, which claims priority to French application 1253591 filed Apr. 19, 2012, both of which are hereby incorporated in their entireties. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a support system for an equipment item on a concrete slab in a machine room of a power station. It also relates to a method for producing such a system. 
       BACKGROUND 
       [0003]    In the electrical engineering production installations, equipment items are installed in a machine room of a power station. Such equipment items comprise, for example, heat exchangers, reheaters or pumps. Some equipment items take the form of a large cylinder that extends horizontally. Two feet are provided close to each of the ends to place the equipment item on a slab of the installation. The slab can be produced directly on the ground or be a floor between two rooms. These equipment items are very heavy, their weight being of the order of tens or even hundreds of tons. 
         [0004]    It is generally planned to install these equipment items at the time of the construction of the building which shelters them. The concrete slab is first of all poured, the equipment item is put in place then a further floor on top of the equipment item is produced. 
         [0005]    It is planned to place the equipment item on plinths made of a single piece with the slab, each plinth supporting a foot of the equipment item. The top surface of this plinth has to be of good geometrical quality. Furthermore, it must include anchoring elements in order to establish a mechanical link between the foot and the plinth. These elements must be positioned accurately in order to correspond to the geometry of the equipment item. 
         [0006]    For this, provision is made to produce the plinth with formwork so that the plinth can be poured at the same time as the slab. A reservation is also provided in the top part of the plinth. Then, the anchoring elements are placed accurately in the reservation and in a second phase, concrete is poured to fix the anchoring elements. The equipment item is then put in place when concrete has hardened sufficiently. 
         [0007]    This method therefore entails two concrete pouring phases, each time with waiting times for the hardening which are measured in weeks. Now, it is important not to delay the construction work site, in particular the construction of the upper floor which can be done only when the equipment items are in place. 
         [0008]    The invention aims to provide a support system for an equipment item on a concrete slab which is quick to implement, while retaining the equipment item positioning accuracy. 
       SUMMARY 
       [0009]    With these objectives in view, the subject of the invention is a support system for an equipment item on a concrete slab comprising at least one raised block relative to the slab and of a single piece with the slab, wherein the block includes a metal belt delimiting the vertical walls of the block and a metal support fastened to the belt and capping the block to receive a foot of the equipment item. 
         [0010]    By producing the block with a metal belt, a means is available to fasten the support thereto in the desired position, in particular altitude-wise, and without it being necessary to carry out a second concrete pouring phase. The equipment items can therefore be placed at the right altitude with no second concrete pouring phase, which makes it possible to accelerate the completion of the work site. 
         [0011]    According to an additional feature, the belt includes connection means protruding inward to link the belt to the concrete. The mechanical link between the belt and the concrete of the block is thus perfectly assured. 
         [0012]    According to one embodiment, the connection means are studs welded onto the belt. This technique is more than adequately proven and makes it possible to obtain the desired result. The studs generally have a cylindrical body and a head that is wider than the body. The body is welded at the end, at right angles to the internal surface of the belt. The block is optionally complemented with conventional concrete reinforcement, but in most case, the reinforcement of the block is not necessary. 
         [0013]    According to a particular arrangement, the support comprises drop edges at its periphery, the drop edges surrounding the belt and being fastened thereto by welding. The support can be adjusted in position by sliding vertically over the belt. Once the position is adjusted, the drop edges are welded onto the belt, which ensures an excellent mechanical link between the belt and the support, with the desired position accuracy. 
         [0014]    To support equipment items comprising two feet, the support system comprises, for example, two blocks distributed over the slab in a main direction, one of the blocks comprising sliding means for the foot that it supports to slide on the block in the main direction. The system is thus able to accept a longitudinal expansion of the equipment item. 
         [0015]    According to a particular constructive arrangement, the sliding means comprise two rules extending in the longitudinal direction along two parallel guiding faces of the foot. In addition to bearing the foot on the support, the two rules limit the possibilities of the foot slipping sideways, while leaving the foot free to slide on the support in the main direction. 
         [0016]    According to a refinement, at least one of the rules also comprises a tab overhanging a corner face of the foot forming an angle with the correspond guiding face to prevent any lifting of the foot. In addition to the lateral guiding, the rule thus provided with a tab prevents lifting of the foot, so as to ensure the link even in the event of an earthquake. 
         [0017]    Another subject of the invention is a method for producing a support system for an equipment item whereby the following steps are carried out:
       installation of a formwork to delimit a block on top of a slab, and reinforcement for the slab and the block, and   pouring of concrete for the slab and into the block formwork,   the method wherein the formwork is a metal belt, and, after the pouring and the hardening of the concrete, a metal support capping the block to receive a foot of the equipment item is then fastened to the belt.       
 
         [0021]    According to this method, there is only one concrete pouring step. The support system is thus available more rapidly than in the prior art, according to which two concrete pouring steps were needed. This production method is therefore more rapid. 
         [0022]    According to other features of the method:
       the belt is equipped first with connection means between the belt and the concrete;   the support is fastened to the belt by welding after its position has been set;   the foot is fastened onto the support by welding; this operation does not require any particular preparation of the support or of the foot and it produces a total link between the foot and the support.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The invention will be better understood and other particular features and advantages will become apparent on reading the following description, the description referring to the appended drawings in which: 
           [0027]      FIG. 1  is a side view of an equipment item and of the support system of the invention, 
           [0028]      FIG. 2  is a partial cross-sectional view along the line II-II of  FIG. 1 ; 
           [0029]      FIG. 3  is a perspective view of a belt used for the support system of  FIG. 1 ; 
           [0030]      FIG. 4  is a cross-sectional view along the line IV-IV of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    The support system  3  of the invention is implemented for an equipment item  1  as shown schematically in  FIG. 1 . Such an equipment item  1  is of cylindrical form and comprises two feet  11 ,  12  close to its two ends. Such an equipment item  1  is generally made of steel by boiler making operations. 
         [0032]    The feet  11 ,  12  comprise vertical webs and baseplates  33 ,  33 ′ having a planar surface  330 ,  330 ′ oriented downward. 
         [0033]    The support system  3  comprises two blocks  31 ,  32  intended to receive, respectively, the two feet  11 ,  12 . The blocks  31 ,  32  are of a single piece with a concrete slab  2  which forms a separating floor between a room below  4 , under the floor, and a room above  5  in which the equipment item  1  is placed. The blocks  31 ,  32  have a rectangular parallelepipedal form protruding from the slab  2 . 
         [0034]    Referring to  FIG. 2 , the block  31  is surrounded by a metal belt  310 , for example made of steel. As  FIG. 3  shows, the belt comprises rows of welded studs  311  protruding inward from the belt  310 . The welded studs technique is widely known and used, in particular for the construction of hybrid bridges comprising steel girders and concrete aprons. It will not be detailed more here. The metal belt  310  also comprises anchor bars  3101  extending downward and intended to produce the anchorage for the block  31 ,  32  in the concrete of the slab  2 . 
         [0035]    The space delimited by the belt is filled with concrete  312  in continuity with the concrete of the slab  2 . 
         [0036]    The block  31  also comprises a support  35  comprising a metal plate  350 , for example made of steel, and drop edges  351 , of the same nature. The drop edges  351  extend vertically along the metal belt  310  and are fastened thereto by welding. A space is retained between the top part of the concrete of the block  31  and the plate  350 . The block  32  is produced in the same way as the block  31  and comprises a support  35 ′ comprising a plate  350 ′. 
         [0037]    The baseplate  33  rests on the support  35  and is fastened thereto by welding for a first of the two feet  11 , either continuously, as shown in  FIG. 2 , or discontinuously. For the case of the second foot  12 , shown in  FIG. 4 , the baseplate  33 ′ rests on the support  35 ′, but without being fastened thereto. Instead, the support system  3  comprises two rules  36  extending in the main direction along the edges of the baseplate  33 ′, facing guiding faces  332 . Furthermore, each rule  36  comprises a tab  360  overhanging the baseplate  33 ′ facing a corner face  331  of the foot forming an angle with the guiding face  332 . The tabs  360  thus form an obstacle to any lifting of the second foot  12 . 
         [0038]    For the production of the support system  3 , during the preparation of the slab  2 , the belts  310  are placed in the appropriate positions and reinforcement  20  is put in place. Then, the concrete of the slab  2  and that of the blocks  31 ,  32  is poured inside the belts  310 . As soon as the blocks  31 ,  32  are accessible, the supports  35 ,  35 ′ are put in place by adjusting their position, in particular their level. While maintaining this position, it is fastened by producing weld beads  37  between the drop edges  351  and the belt  310 . It goes without saying that the length and the size of the beads  37  is sufficient to transmit the forces to be supported by the support  35 ,  35 ′. The weld beads  37  may be continuous, as represented, or discontinuous. 
         [0039]    Then, the equipment item  1  is put in place such that the feet  11 ,  12  bear on the supports  35 ,  35 ′. The position of the equipment item  1  is adjusted, then weld beads  34  are produced on the periphery of the baseplate  33  to fasten the baseplate  33  onto the support  35  of the first foot  11 . With regard to the second foot  12 , the rules  36  are put in place along the guiding faces  332  of the baseplate  33 ′ and they are also fastened by weld beads  38  onto the support  35 ′. 
         [0040]    In operation, the equipment item  1  is likely to expand, in particular if it is passed through by fluids at medium and high temperature. This expansion is translated into a variable distance between the two feet  11 ,  12 . When this distance varies, the baseplate  33 ′ of the second foot  12  slides on the support  35 ′ by being guided by the rules  36 . 
         [0041]    In case of earthquake, the first block  11  takes up the stresses in any direction. On the second block  12 , the rules  36  prevent the lateral displacement, the tabs  360  prevent the lifting, whereas the longitudinal stresses are taken up by the first block  11 . 
         [0042]    The invention is not limited to the embodiment which has just been described by way of example. The form of the equipment item may be different. It may have only one foot, or, on the contrary, more than two feet. In the latter case, only one will be fixed, the others being designed to slide.