System and Method of displacement volumes in composite members
Background of the Invention
[Field of the Invention]
The invention relates to the design and implementation of series of displacement volumes in three-dimensional construction members of composite materials placed in an exact uniform geometrical grid determined and fixed by a spacing system integrated in a three-dimensional steel structure, flexible forming in arbitrary direction with regards to curvature and angles
As prior art lacks flexibility, both concerning the markets increased demands for flexibility and precise assembly as well as range of applicability, the present invention solves these issues in a simple and economical manner. The enhanced range of applicability will lead to environmental benefits through substantial material reduction. In addition, a part of the increased range of applications relates to improvement of infrastructure and buildings in non-industrialized countries.
[Description of the Prior Art] In the 1990'ies, the biaxial hollow slab [EP0552201] was invented. This invention incorporated hollow bodies in concrete slabs in order to save material and weight. Different methods of incorporating the hollow bodies as well as designing these were described.
This patent describes the optimal structural size and placement of voids in structural biaxial concrete members. It also describes a simple and economical way of locking these voids using the already necessary top and bottom reinforcement which always will be present in structural concrete slabs. The invention covers the situations where top and bottom reinforcement is present, like a concrete slab. The setback from this invention is both the presence of top and bottom reinforcement as well as the lack of flexibility in three-dimensional structures like curved walls or slab on ground following contour lines. Patent [EP0552201] also describes ways of creating complete voids from partials of spheres / ellipsoids, but does not come with a solution to the strength related problem for voids assembled by partials of spheres.
Several applications, [JP2003171994]; [JP2004092166]; [J P2004176309]; [JP2004244938]; [JP2005146721]; [J P2005163340]; [JP2005188265]; [JP2005282010]; [JP2005105596]; [JP2005315065]; [JP2006089994]; [JP2006009363], [JP2006138166]; [JP2007032055]; [JP2007113337], addresses patent [EP0552201] trying to implement additional connection features in order to make creative ways of fixing the individual
i
voids between the top and bottom reinforcement without direct contact with one or both reinforcement meshes, apparently in order to find a way around patent [EP0552201] not violating this patent's claims referring to the optimal solution by using only the already present reinforcement meshes.
All these applications are highly impracticable and as a consequence expensive both in material consumption, fabrication and carrying out.
[WO02092935] describes methods which mainly are covered in patent [EP0552201] and in full the final system after patent [EP0552201]. Additional described methods are obviously less practicable and more expensive.
[WO2005080704] describes a method of fixing a row of balls in a specially fabricated mesh, which is bended to fix the individual balls.
The drawbacks from this method are several: a) Superfluous use of non-functional steel b) Need for special fabrication of meshes and bending of these c) Lack of control of distances between rows of balls. (All existing theory and tests demands control of the voids in three directions). d) Time consuming placing of individual balls in bended mesh e) Time consuming placing of each row of balls between reinforcement meshes f) Lack of control of exact placement of reinforcement meshes g) Special prefabricated reinforcement meshes with modularity corresponding to modularity of voids in order to allow voids to penetrate meshes h) The final structure is identical with [EP0552201]
[JP2006152657] describes a lightweight embedding material, a lightweight embedding material structure and a formation device of the lightweight embedding material capable of being economically manufactured by one moulding type. The major setback from this design is the lack of ability for stacking due to the stabilizing interlocker. Hence this expensive design will be even more costly due to expensive transport costs (of air).
[J P2004176309] This application is almost a direct copy of [EP0552201], and thus already covered.
Description
Compared to prior art, the present invention creates enhanced flexibility, thereby enabling incorporation of the system in a far broader range of applications in the fields of composite materials for use in all building members and civil constructions like walls, slab on ground, floating foundations, coastal protection and roads, flexible forming in arbitrary direction with regards to curvature and angles, thus meeting the markets increased demands for flexibility and precise assembly as well as increased range of applicability and possibilities.
Compared to prior art, the present invention solves several existing problems concerning displacement volumes in structural members relating to strength, transport and assembly, thereby obtaining a cost effective quality product with regards to material reduction, reduced transport and precise assembly.
The present invention describes a displacement system, consisting of series of displacement volumes placed in an exact uniform geometrical grid determined by a spacing system integrated in composite members through a geometrical locking system in form of special designed three-dimensional steel structures, securing fast and precise implementation, and designed to ensure integrity and to increase shear strength of the present composite member.
The present invention also describes a method for practical execution of said displacement system.
Detailed Description of the Invention
The present invention comprises a displacement system, which solves several existing problems concerning displacement volumes in composite members concerning flexibility, thereby enabling incorporation of the system in a far broader range of applications
The present invention further solves several existing problems relating to strength, transport and assembly, thereby obtaining a cost effective quality product with regards to material reduction, reduced transport and precise assembly.
All present tests and studies are based on an exact uniform geometrical placement of the displacement volumes as well as the location of the structural steel relative to the displacement volumes and overall geometry of the structural member. For being able to
use these test and studies for validation in a practical execution, it is evident that a displacement system must enable an exact placement of displacement volumes. An effective displacement system is obtained if volumes are positioned in an exact uniform geometrical grid, where the ratio between diameter of volumes and distance between centres of volumes, measured as the shortest distance in same plane, is between 0.5 and 1.
This invention enables the exact geometrical placement of said volumes and steel, through the implementation of a spacing system integrating displacement volumes in a three-dimensional steel structure.
The exact position of the displacement volumes can either be controlled by a spacing system integrated in the volumes, or by an external spacing system controlling the volumes.
Compared to complete displacement volumes, where the transport is very expensive and a substantial part of the total costs, the transport of partial, stackable bodies, which is to be assembled at the arrival point, costs up to 75 % less.
At the same time a described design/method secures fast and accurate assembly, which further minimizes the costs. The specific design/method using series of displacement volumes solves the strength related problems for displacement volumes assembled by partial bodies. The contact line between two shells of partial bodies is a very week point, and prone to break open when load is imposed parallel to the contact line. In reality, this force will always be vertical due to gravitation, coming from stacking, workers, equipment and related items. This is solved by the present method, where the contact line is controlled / fixed in a horizontal position, hence never exposed to forces parallel to the contact line. Another positive side effect of the controlling of position is material reduction compared to singular displacement volumes made of partial bodies why the system reduces the amount of steel needed to fix the displacement volumes in their preferred position.
The displacement volumes can be made of preferably recycled / waste products such as plastic, or fibre-material, and can be of any specific form, from partial shells to complete and final displacement volumes of any form.
A cost effective quality displacement system with regards to material reduction, transport and assembly is obtained.
Displacement volumes integrated in special designed three-dimensional steel structure gives enhanced flexibility concerning handling, forming and strength. The material in the steel structures is fully valid for giving strength when incorporated in members of hardening material and for securing integrity within the construction member, Hence, no superfluous material is used.
The steel structures are made by standard material and by standard methods, and can be calculated by standard methods with regards to bending strength. The special spacing system gives enhanced flexibility in forming the desired building member. It can be executed vertically, horizontally or slanted allowing for curved walls and roofs, as well as slab on ground following the contour lines of the terrain.
The integration of displacement volumes and lattice structures in building members can be executed with supplementary reinforcement meshes on one or more sides of the displacement-lattice.
The displacement system can be integrated in composite building members where one or more of the sides are furnished with a plate of either a non-hardening or a hardening material. The full and final building member is obtained by adding one or several other layers of non-hardening and/or hardening material. A plate of non-hardening material can be directly connected to the three-dimensional steel structure by welding or standard anchoring methods. The three-dimensional steel structure can be partly or fully integrated in a plate of hardening material by means of bonding.
The placing of non-hardening material and/or casting of hardening material can be done either on factory or on the building site.
The displacement volumes can have a small gap larger than zero mm in relation to the rods in the three-dimensional steel structure thus allowing the bodies to act as imposed vibrators upon normal vibrating of the hardening material if said three-dimensional steel structure is to be integrated in a building member of any hardening material, in order to achieve a faster and better vibrating of the hardening material.
The placement of the hardening material must be done skilfully in sequences as the geometry and weight of the displacement system combined with the adhesion between the hardening material and the specially designed three-dimensional steel structure allows for a first layer of hardening material being cast to a distance covering up to 10 %
of the displacement volumes height without the floating ability of the displacement volumes exceeds the adhesion effect and frictional resistance of the steel structure.
A very important aspect is that the special three-dimensional steel structure can be designed and skilfully placed in a first layer of hardening material to provide essential resistance for bonding between a first and a second layer of hardening material, hence ensuring integrity in the composite member. Furthermore, the special three-dimensional steel structure can be designed to provide adequate resistance towards shear forces, whether the construction member is used as a vertical or horizontal structure.
The flexibility in the system allows for incorporating a range of different materials in composite members, thereby obtaining advantageous characteristics.
In addition to the material reduction caused by the displacement volumes, the volumes contain air, which behaves as insulation. This effect can be increased by adding a layer of material with insulation effect between the displacement volumes in the middle of a composite member. Adding such a layer of material with high insulation, either a soft density material or a hardening material, can be executed either by pouring or spraying or pressing said material into between the displacement volumes, or by pressing the displacement system into the insulation layer, depending on manufacturing preferences.
The flexibility of the displacement system is ideal for slab on ground and earth protection. The system allows for incorporation of materials in layers optimal for acting as membrane towards moisture and temperature insulation. A slab on ground will generally consist of layers with three main characteristics. The lowest layer should act as sealing layer to prevent capillary action, next an insulation layer either hardening or non- hardening, followed by an upper hard surface acting as basement layer for the construction. The displacement system can be integrated with the displacement volumes forming part of the insulation layer. The insulation layer could be made by, but not limited to, either hardening foam directly sprayed into the displacement system or plates of a softer insulation material pressed skilfully into the displacement system from both sides. The displacement system can be executed with varying degrees of prefabrication. The most simple consist of the displacement system without layers of described materials, while the most advanced consist of a displacement system integrated with a layer of insulation and a hard outer layer facing upwards when implemented, acting as basement layer for a possible construction. The semi prefabricated part will then be pressed into the sealing layer on site. The three-dimensional steel structure secures integrity between the layers.
The displacement system can be integrated in a hardening material, especially useful with low cost solidification/stabilisation systems, for use in all types of slab on ground, including but not limited to, roads and coastal protection. For roads, a layer of bitumen can be added, as the hardening material with the integrated three-dimensional steel structure provides for a sufficiently stiff and stable base. This type of road is especially relevant in areas prone to severe rain/flooding, which can erode the road if base carried out of loose sand/gravel/stone. For coastal protection, the flexibility of the system allows for a stable covering following the contour lines of the terrain constituting the coastal protection. Following contour lines involves casting of a hardening material on slanted surfaces. This is made less complicated with the present invention since the displacement volumes enable the hardening material to set to a far higher degree than without displacement volumes instead of being dragged by gravity towards lower vertical levels. The enhanced range of applicability will lead to environmental benefits through substantial material reduction, especially with applications relating to improvement of infrastructure and buildings in non-industrialized countries where access to resources like aggregates and cement is limited and expensive, and often involves non- environmental friendly, heavy transport over very long distances.
An alternative example of the inventions diversity is incorporation of an outer layer of thermo tropic crystals fixed by the steel structure. Thermo tropic crystals transform into liquid phase in case of heating and can be used both in relation to temperature regulation and for design reasons.
The practical execution of the displacement system in a hardening material must be done skilful in order to avoid problems with floating of the displacement system due to up drift caused by the hardening material upon the displacement system, especially the displacement volumes.
Controlling the position of the displacement system can be done en several ways, but one method is more practical than others.
First, the displacement system is placed, with or without spacers, on a given surface, or partially pressed into a relatively soft material, and with or without fixing means between the displacement system and the layer of a material.
Second, a flowing form of a hardening material is gently and skilfully distributed above said displacement system, so as this flowing material is carefully positioned in a specific height ranging from the given surface, covering a predefined part of the displacement system, so a combination of vertical force and frictional resistance between the displacement system and the hardening material prevents the displacement system from floating due to up drift on the displacement system from the hardening material.
Third, if necessary, the layer of hardening material can be vibrated by normal means. As the displacement volumes are placed with a minor gap to the three-dimensional steel structure, the displacement volumes will react upon any vibrating of the hardening material as they are in direct contact with said hardening material, hence acting as imposed vibrators.
Forth, above this layer of hardening material additional layers can be placed of either non-hardening or hardening materials.
The three-dimensional steel structure is designed to be fixed in all present rigid layers enabling full coherence in the final building member comprising the layers and the three- dimensional steel structure.
Detailed description of the drawings
Fig 1 is showing two series (105) of shells (100), each in the shape of partials of full displacement volumes (108) (normally partials of spheres / ellipsoids), designed to assemble one and one to create relevant series (110) of full displacement volumes. The partial displacement volumes are dislocated by a spacing system (120). The brim (130) of the partial displacement volumes is designed as to enable the two partial shells to assemble tight to each other to make a stable joint. Male portions or latches (135) extrudes from the brim, designed to connect and fasten into female portions or openings (136) in brim (130) of corresponding shell (100) together creating a full and final displacement volume (108).
Fig 2 is showing one series (105) of shells (100), designed to assembly by bending one half of the series (105) in the hinges (137) to create series (1 10) of full displacement volumes (108).
Fig 3 is showing the incorporation of a rim (140) designed so as to be assembled between two partial shells (100), all three parts interlocking to a full displacement volume
- individual or as series. The rim (140) can either be individual or part of series (150) of rims.
The rim (140) can be designed to act as a reinforcing rim strengthening the completed full displacement volume (108).
Fig 4 is showing the incorporation of series (150) of rims interlocking two or more series (105) of shells, together coupling multiple displacement volumes (108).
Fig 5 is showing the series (1 10) integrated as part of a fixed, geometrical structure together with lattice structures (220), normally made of steel, but not limited to steel, composed by longitudinal steel (200) and angular steel (205). The lattice structures are designed so the displacement volumes (108) fit in the openings in the angular steel (205), thereby fixing the displacement volumes (108) in the lattice structures (220). Longitudinal steel (210) can be connected to the angular steel (205) to control the movement between the displacement volumes (108) and the lattice structures (220). Depending on the actual use, the series (110) of displacement volumes (108) and the lattice structures (220) can be linked for practical reasons through two or more connectors (230) made of steel or other material. These connectors (230) can placed anywhere on the lattice structures (220), and can be coupling two or more lattice structures (220) in transverse direction. The connectors are normally made of steel, but not limited to steel.
Fig 6 is showing the series (1 10) integrated as part of a fixed, geometrical structure together with special lattice structures (240), normally made of steel, but not limited to steel, enabling a change in angle between series of bodies (110).
Fig 7 is showing the series (1 10) integrated as part of a special welded, three- dimensional structure (250) consisting of two or more lattice structures (220) connected with curved connectors (230) enabling a curvature in the plan through the series of bodies (110).
Fig 8 is showing the series (1 10) integrated as part of a fixed, three-dimensional structure (250) together with lattice structures (220), normally made of steel, but not limited to steel, where one or several sides of the structure is furnished with a plate of, normally but not limited to, non-hardening material like metal (fixed directly to the structure (250) by welding or standard anchoring methods) or a hardening material (300) (fixed to the three-dimensional structure (250) by hardening/adhesion)
Fig 9 is showing the three-dimensional displacement system (250) integrated in a slab on ground system. The lowest layer (330) in vertical direction should act as sealing layer to prevent capillary action, next an insulation layer (320) of either hardening or non- hardening material, followed by an upper hard surface (310) acting as basement layer for the construction. The displacement system (250) can be integrated with the displacement volumes (110) forming part of the insulation layer (320).
Reference list for Drawings
100 Shell
105 Series of shells
108 Full displacement volume
110 Series of displacement volumes
120 Spacing system
130 Brim
135 Male portion / latch
136 Female portion / opening
137 Hinge
140 Rim
150 Series of rims
200 Longitudinal steel
205 Angular steel
210 Longitudinal steel
220 Lattice structure
230 Connector
240 Lattice structure
250 three dimensional unit
300 Plate
310 Hard layer
320 Insulation layer
330 Sealing layer against capillary action