Abstract:
The present invention broadly comprises a method and apparatus for constructing a concrete structure, where one embodiment of apparatus includes a pre-cast concrete component and a poured in place concrete surface supported by the pre-cast concrete component.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119(e) to U.S. Application No. 62/114,219, filed Feb. 10, 2015, the entire content of which is incorporated into the present application by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a method and apparatus for constructing a concrete structure. In particular, the invention relates to constructing a concrete structure using pre-cast concrete components. 
       BACKGROUND OF THE INVENTION 
       [0003]    Natural gas is becoming a greater and greater share of the U.S. energy supply due to advances in hydraulic fracking. Natural gas is generally sent through a pipeline to a terminal, where it is compressed to liquefied natural gas (LNG) before loading it into tanks for transport. This terminal generally includes a platform to support 4-7 compressors, each of which weighs several tons. Due to the increased supply of natural gas, additional terminals are needed to process the supply. However, the terminals are presently constructed by pouring concrete in place for all of the structure, which can take on the order of six months. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention broadly comprises a method and apparats for constructing a concrete structure. One embodiment of the invention may be implemented as an apparatus including a pre-cast concrete component and a poured in place concrete surface supported by the pre-cast concrete component. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    A full and enabling disclosure of the present subject matter, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
           [0006]      FIGS. 1-8  illustrate a process for making a concrete structure according to an exemplary embodiment of the present invention; 
           [0007]      FIG. 9  illustrates several views of one embodiment of a column and a column cap; 
           [0008]      FIGS. 10 and 11  illustrate perspective views of embodiments of the column cap with floor portions stacked thereon; 
           [0009]      FIG. 12  illustrates an top view of the floor sections supported by the column cap; 
           [0010]      FIGS. 13 and 14  show side views of the floor sections supported by the column cap; and 
           [0011]      FIG. 15  shows a perspective cutaway view of the floor sections supported by the column cap; and 
           [0012]      FIG. 16  shows close up side section views of the floor sections supported by the column cap. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0013]    Reference is presently made in detail to exemplary embodiments of the present subject matter, one or more examples of which are illustrated in or represented by the drawings. Each example is provided by way of explanation of the present subject matter, not limitation of the present subject matter. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present subject matter without departing from the scope or spirit of the present subject matter. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present subject matter covers such modifications and variations as come within the scope of the disclosure and equivalents thereof. 
         [0014]      FIGS. 1-8  show exemplary process steps for constructing a structure  10  in accordance with the present invention.  FIG. 8  shows the final structure  10  in one embodiment of the invention. Structure  10  includes columns  20  to support the main surface  50 . Main surface  50  supports the compressors used to compress the LNG. Main surface  50  includes apertures  52 A,  52 B, and  52 C. These apertures allow pipes (not shown) to access the compressors from below main surface  50 . These pipes may link the compressors to each other, as the compression is done in stages. The pipes may also connect to storage tanks to pull off components of the natural gas that liquefy during a particular compression stage. 
         [0015]    In the embodiment shown in  FIG. 8 , there are 6 stages to the compression process. Thus, there are 6 sets of apertures  52 A,  52 B, and  52 C. The compression process compresses the natural gas from approximately 5-20 psi to approximately 1,700 psi. Natural gas is mostly methane, but does include other hydrocarbons. Thus, there are other components of the natural gas that liquefy before the methane does. Accordingly, some of the compressors are designed to pull off these other components as the natural gas is compressed. In this regard, the two left-most compressors on main surface  50  need three apertures to provide the piping necessary for their compression stage, while the other four compressors only need two apertures. However, any number of stages and access apertures are within the scope of the invention. 
         [0016]      FIG. 1  shows that the first step includes placing columns  20 . Column caps  30  are then placed on the columns in  FIG. 2 .  FIG. 9  shows column  20  and column cap  30  in greater detail.  FIG. 3  shows that side portions  40  and floor portions  42  are then placed on the column caps  20 . All of these components are pre-cast concrete components, so this process can be done relatively quickly. 
         [0017]      FIG. 4  shows that the side portions  40  and floor portions  42  are assembled for the first third of the structure. Floor portions  42  are designed to include the apertures  52 A,  52 B, and  52 C. As shown in  FIG. 5 , concrete may now be poured to create the main surface  50  for the first third of the structure  10 . These pours may be done incrementally, for example breaking each third into 5 pours as shown in  FIG. 1-8 . This allows workers to begin constructing the middle third of the structure, as shown in  FIG. 5 . 
         [0018]      FIGS. 6 and 7  show the middle and final third of structure  10  being constructed in a similar manner as the first third. Finally,  FIG. 8  shows the completed structure. 
         [0019]    Again, as most of the components are pre-cast components, construction can be completed much faster than a structure made of poured in place concrete. The present invention minimizes the used of poured in place concrete, allowing dramatic time savings over the present construction techniques. 
         [0020]      FIG. 9-16  provide greater detail of the pre-cast components  20 ,  30 ,  40  and  42 . Columns  20  may have steel reinforcement members  22 , as shown in  FIG. 13 . Column caps  30  may also have steel reinforcement members  36 , also shown in  FIG. 13 . Column caps also include support member  32  and alignment projection  34 . Support member  32  supports the floor portions  40  that are stacked on the column caps  30 . Alignment projections  34  allow the floor portions  40  to be locked into place on the column cap  30 .  FIG. 15  shows a perspective view of the floor portions  40  supported by support member  32  and aligned by alignment projections  34 . 
         [0021]    Floor portions  40  may also include steel reinforcement member  44 , as shown in  FIG. 15 . Floor portions  40  are locked in place on the column caps by the alignment projections, and may also be linked to each other. Once main surface  50  is cast over the floor portions  44 , all of the components are locked together by main surface  50 . 
         [0022]    The compressors used to compress the natural gas cause a reciprocating load on the supporting structure, which requires a support with isotropic load-bearing properties. As pre-cast components typically are not isotropic, pre-cast components have not been used to support these types of compressors before. In this regard, typical pre-cast components can support 4-5 times the load in a primary direction as opposed to the load that can be borne in secondary directions. For example, pre-cast bridge components typically can support 4-5 times as much load in the traffic direction as compared to the transverse direction. In contrast, the disclosed composite structure can support approximately the same load in all directions. Thus, the present inventors have combined reinforced pre-cast components with a partial poured in place surface to create a composite structure that has the isotropic properties to support the compressors, while being capable of being constructed using much less time and labor than conventional poured in place structures. 
         [0023]    The present written description uses examples to disclose the present subject matter, including the best mode, and also to enable any person skilled in the art to practice the present subject matter, including making and using any devices or systems and performing any incorporated and/or associated methods. While the present subject matter has been described in detail with respect to specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art.