EP1803872A1

EP1803872A1 - Concrete structure and method of construction

Info

Publication number: EP1803872A1
Application number: EP05028686A
Authority: EP
Inventors: Carsten Thrue
Original assignee: ABB Technology AG
Current assignee: ABB Technology AG
Priority date: 2005-12-29
Filing date: 2005-12-29
Publication date: 2007-07-04
Anticipated expiration: 2025-12-29
Also published as: EP1803872B1; ATE483869T1; CN1991111B; CN1991111A; DE602005024034D1

Abstract

A compact secondary substation (30) for an electrical apparatus, such as a transformer, comprising a foundation plate (31), two concrete panels (32,33) provided as walls on opposites sides of the foundation plate (31) and fastened to the foundation plate, a roof (34) covering the space (35) between the two concrete panels (32,33) and optionally fastened to the panels, a gable at each end of the substation wherein at least one of the gables is made of sheet metal parts and comprise a door (42) entrance.

Description

FIELD OF THE INVENTION

The present invention relates to a concrete structure, for example a transformer station.

BACKGROUND OF THE INVENTION

Compact Secondary Substations (CSS), for example electrical transformer stations, produced in concrete material is in general a well known concept. The material is preferred because of its weather ability, structural properties, design possibilities, fire properties and it's generally well known properties within the building industry.
Most often the Compact Secondary Substations are made in specially prepared moulds, allowing little or no deviation from initial design regarding wall openings or its like. The usage of moulds might be a proper production method when producing high numbers of products, but possibilities of customization of the moulded buildings is mainly time consuming and expensive.
The doors and the hinging of doors is often a problem within CSS Concrete buildings. Generally the doors are made as a concrete filled pre-welded steel frame, resulting in a heavy construction with substantial loads on hinges as consequence.
When installing a CSS Concrete, foundation plates in the lower parts of the building are demounted in order to allow cables to be mounted and others. The mounting of the foundation plates, which are most often produced in galvanised steel, requires inserts or similar in the concrete parts allowing mounting and demounting. Quite often this is resulting in tolerance problems, or quite complex designs that eliminate tolerance problems.
For architectural purposes a Concrete CSS often should imply the possibility to be customer adapted, either by means of specially prepared openings in the concrete walls for compartments or similar, or by means of special concrete surfaces.

DESCRIPTION / SUMMARY OF THE INVENTION

It is therefore the object of the invention to provide a Compact Secondary Substations (CSS) not having the disadvantages as summarised above. In particular, it is the purpose of the invention to provide a flexible solution for the built up of CSS, for example electrical transformer stations.
This purpose is achieved by a compact secondary substation for an electrical apparatus, such as a transformer, comprising a foundation plate, two concrete panels provided as walls on opposites sides of the foundation plate and fastened to the foundation plate, a roof covering the space between the two concrete panels and optionally fastened to the panels, a gable at each end of the substation, wherein at least one of the gables is made of sheet metal parts and comprises a door entrance.
A method according to the present invention for providing a Compact Secondary Substation comprises moulding two concrete panels as walls, providing a foundation plate and a roof, erecting the two panel on opposite sides of the foundation plate, fastening the panels to the foundation plate and connecting the roof to the top of the two panels, providing end gables at each end of the substation, wherein at least one of the gables is made of sheet metal parts and comprise a door entrance.
According to a specific embodiment the method the moulding of one of the two concrete panels comprises providing a flat bedplate as moulding surface, erect mould sides on the bedplate to define edges of the panel and openings in the panel, fill concrete into the mould and remove the mould sides and the bed plate after concrete hardening. The erect mould sides may for example be chipboard sides.
Pre-cast concrete panels according to the invention are easy to manufacture, for example as flat walls. They can be made without the necessity of a pre-manufactured mould, using only a flat bedplate as moulding surface. Chipboard sides may be erected on the bedplate, creating a one-off mould that eventually is torn apart when the concrete panel is de-moulded. Reinforcements, inserts and other parts to be moulded into the concrete panel are placed with coarse tolerances before the mould is filled with concrete.
Using this flexible manufacturing method, a Concrete CSS can be erected. Moulded into the different concrete panels creating the overall structure a number of welding plates allows the concrete panels to be welded together.
By adding a flexible door panel profile made of machined and bended sheet metal, lightweight doors can be attached in a precise way.
The substation in a preferred embodiment is a transformer house with at least a first and a second room, wherein the first room contains the high voltage part of the electricity, namely a high voltage equipment and the second room contains the low voltage part of the electricity, namely a low voltage equipment.
The substation may also contain a third room for the transformer. Consisting of a minimum of three different rooms - the low voltage room, the high voltage room and the transformer room - the overall layout of a CSS can be made simple. Each of the gable ends of the housing may be made entirely of sheet metal parts, allowing full access to the electrical equipment in the low voltage and the high voltage rooms. In the middle of the CSS the transformer may be placed, with access through ventilation doors integrated in the concrete panels. When installing the transformer, the roof can be lifted off the structure.
When a structure is made of pre-cast concrete panels, a normal procedure for attaching doors and other lightweight components is by using bolts or other threaded components.
Lightweight components are defined as components that do not load its supporting structure - the concrete panel - with substantial forces. The magnitude of these forces may vary from application to application and should be defined more specifically in each case.
In most designs the support of lightweight components includes threaded inserts to be placed correctly on the concrete panel mould, or similar steel part devices especially prepared for each application.
These steel parts are typically not following a standard, but are usually manufactured from application to application. Often, the steel parts are produced locally at the concrete panel manufacturer, who is normally handling the steel reinforcements used in concrete panels. The result is generally improvised solutions, costly and inappropriate steel parts. The most commonly seen device is a flat, massive steel plate with threads added to the side placed against the concrete panel mould.
The mechanical strength of designs like these is often way above needs, often meaning that parts are more expensive than required.
Using standardized thread inserts, which can be positioned against a concrete panel mould, tends to lower costs to what might be an acceptable level. However, there might be a high effort involved in the positioning of these standardized thread inserts, since these most commonly has tubular shape. Attaching the standardized thread inserts to the concrete panel mould could prove time consuming, with relatively high tolerances involved. Also, there is the possibility of the standardized thread insert to tilt when the liquid concrete is distributed in the concrete panel mould.
The compact secondary substation according to the invention may have an embodiment wherein the concrete panels of the substation comprise first profiles constituting first metallic welding plates partly integrated in the concrete panels and wherein the foundation plate comprises second profiles for welding connection between the panels and the foundation plate.
Furthermore the compact secondary substation according to the invention may have an embodiment wherein at least one of the concrete panels of the substation comprises a second profile constituting a door frame moulded into the concrete panel.
Furthermore the compact secondary substation according to the invention may have an embodiment wherein the first profile or the second profile or at least one are generally U shaped or C-shaped with a base and a first and a second part extending laterally from opposite edges of the base to form the legs of the U shaped or C-shaped cross section, wherein the first part has a row of segments resembling a teeth-like structure along the edge of the base and the second part extends into a third part that is bend at an angle relatively to the second part.
Often the lightweight components require more than one connection point to the supporting structure, meaning that position tolerances between two connection points becomes critical. In the example of attaching a sheet metal door to a concrete panel structure, the upper and lower hinge of the door should be attached in a way securing the door to open and close correctly. If the interrelated distances between the two hinges are not having narrow tolerances, the door would never work properly.
When producing pre-cast concrete panels, the entire handling of the concrete panel during the production speaks against narrow tolerances. Forces from the vibration of the concrete are significantly, spoiling any accurate positioning of any devices, as does the forces emerging from the distribution of the liquid concrete when being held into the mould.
The only way that narrow tolerances between more than one connection point in the concrete panel is possible is by using one insert with the tolerances build in. This could be steel part with pre-manufactured threaded holes or similar. This steel part should have sufficient tearing strength to withstand the pullout forces when mounting e.g. a sheet metal door, and should be manufactured in a way allowing narrow tolerances. Costs are certainly a concern as well.
In order to improve these techniques, in a further embodiment, the compact secondary substation may advantageously contain a profile for embedding in the concrete panel during moulding, the profile having a cross section which is generally U shaped or C-shaped with a base and a first and a second part extending laterally from opposite edges of the base to form the legs of the U shaped or C-shaped cross section, wherein the first part has a row of segments resembling a teeth-like structure along the edge of the base and the second part extends into a third part that is bend at an angle relatively to the second part.
The design of the part allows usage on edges of concrete panels as well as anywhere on the concrete panel sides. This universal usage is important, since it offers maximum flexibility to the concrete panel designer without compromising an industrialized solution with respect to production, using one pre-manufactured type of welding plate generally. The welding plate may be used on both sides of the concrete panels, along edges and on plane surfaces.
Experiments have revealed that the profile is easy to manufacture at low cost, implies a high degree of flexibility to the concrete panel designer, and can withstand a high tearing strength when embedded in the concrete structure. For example, it is suited as welding plates in order to fasten concrete panels to foundation plates of compact secondary substation, such as transformer houses. Other applications are as door frames moulded into concrete panels, for example as used in compact secondary substation, such as transformer houses.
In a further embodiment, the base is flat and the first and the second part extend laterally at a right angle from the base. In an even further embodiment, the end parts of the segments are bent at an angle. Each of the segments may have at least one hole.
In order for the profiles to be combined with reinforcement material in concrete structures, the gaps between the segments may be adapted in accordance with a net mask size of a metal net used for reinforcement of the concrete structure.
In order for the third part to have a high tearing strength when embedded in the concrete, the third part may have a row of holes along the base in order to accommodate concrete inside these holes.
In a further embodiment, the third part has other segments in a teeth-like structure. For example, the gaps between the other segments are adapted in accordance with a net mask size of a metal net used for reinforcement of the concrete structure. Each of the segments may, for instance, have one of the other segments as a counterpart with equal distances from one end of the profile. In addition, the third part may be bent at an angle of between 25 and 65 degrees, preferably between 25 and 55 degrees, for example bent at an angle of around 45 degrees.
In a preferred embodiment, the base is more than two times and less than 5 times, for example around 3 times, wider than the height of the legs of the U-shaped or C-shaped cross section. In addition, the length of the base may be at least 2 times larger than its width, for example around 3 times its width.
Such a profile may be made of a bent sheet of metal.
The profile illustrated as part of a combination may as well be used independently of a substation, as the profile is of a general nature and may be used for other types of concrete panels than the one described in the foregoing.

SHORT DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail with reference to the drawing, where

FIG. 1: illustrates an application in a compact secondary substation for an electrical apparatus transformer,
FIG. 2: illustrates the transformer station with gable doors and ventilation doors,
FIG. 3: shows the transformer station in perspective with transparent roof,
FIG. 4: shows the transformer station in perspective with transparent roof in a different perspective,
FIG. 5: shows the transformer station in perspective with transparent roof in a further different perspective.
FIG. 6: is a detailed image of a profile usable as a welding plate,
FIG. 7: shows the embodiment of FIG. 1 in an end view,
FIG. 8: shows the embodiment of FIG. 1 implemented in a concrete panel,
FIG. 9: illustrates the moulding of the embodiment of FIG. 1 in a concrete panel,
FIG. 10: shows the embodiment of FIG. 1 implemented together with reinforcement material between the segments,
FIG. 11: is a detailed image of profile usable as a door panel,
FIG. 12: shows the embodiment of FIG. 6 in a different perspective view,
FIG. 13: shows the embodiment of FIG. 6 in an end view,
FIG. 14: shows the embodiment of FIG. 6 in an end view with a polymer slab inserted,
FIG. 15: illustrates an application of the embodiment of FIG. 6 as an edge protector.

DETAILED DESCRIPTION / PREFERRED EMBODIMENT

FIG. 1 shows a compact secondary substation 30 for an electrical apparatus, such as a transformer, comprising a foundation plate 31, two concrete panels 32, 33 provided as walls on opposites sides of the foundation plate 31 and fastened to the foundation plate, a roof 34 covering the space 35 between the two concrete panels 32, 33 and connected to the panels 32, 33.
The concrete panels 32, 33 are provided with openings 36, 37 into which ventilation doors 38, 39 as shown in FIG.2 and FIG. 5 can be mounted. The transformer 43 is shown in greater detail in FIG. 4.
As best seen in FIG. 1 in combination with FIG. 2, a gable 40, 41 at each end of the substation 30 is made of sheet metal parts and comprises a door 42 entrance. As best seen in FIG. 3 in combination with FIG. 4 and FIG. 5 the substation 30 in form of a transformer house is provided with at least a first room 44 and a second room 45. The first room 44 contains the high voltage part of the electricity and the second room 45 contains the low voltage part of the electricity. In addition, the substation also contains a third room 46 for a transformer 43. Consisting of a minimum of three different rooms - the high voltage room 44, the low voltage room 45 and the transformer room 46 - the overall layout of a CSS can be made simple. The transformer 43 is shown in greater detail in FIG. 4 illustrating high voltage connections 47 and low voltage connections 48.
The concrete panels 32, 33 as shown in FIG. 1 are fastened to the foundation plate 31 and to the gables by welding plates 1. A welding plate is shown in greater detail in FIG. 6 through FIG. 10.
FIG. 6 is an image of a profile/welding plate 1 in a first embodiment suited as a welding plate in a substation according to the invention. The profile is generally U shaped with a straight base 2 and a first 3 and a second part 4 extending laterally from opposite edges 5, 6 of the base 2 to form the legs 7, 8 of the U shaped or cross section, which is illustrated by the end section in FIG. 7. The profile 1 has a length L, a width W and a height H.
The first part 3 has a row of segments 9 resembling a teeth-like structure along the edge 6 of the base 2 with gaps 13 between the segments. The second part 4 extends into a third part 10 that is bent at an angle 11 relatively to the second part 4. In the figure, the third part 10 is angled at 45 degrees relatively to the second part 4. The third part 10 comprises other segments 12 matching the row of segments 9 from the first part 3 of the U-shape. This row of other segments 12 is angled 45 degrees inwards in the cross section, in order to minimize the circumscribed circle. The length L of the profile is approximately three times the width W of the profile.
Taking an approach from a sheet steel manufacturing point of view, the design of a welding plate is done by machining and bending of a piece of sheet steel.
As illustrated in FIG. 6, all of the segments 9 have through-going holes 19 for tearing strength purposes. The base 2 of the U-shape has a width W which is approximately three times wider than the height of the U-shape side. However, accurate dimensions of the profile can vary from application to application, as well as the ratios mentioned.
By letting the second part 4 of the welding plate 1 be rigid and without holes, the steel part 4 is suited for use around a corner 14 of a concrete panel 15, as illustrated in FIG. 8, which can be useful in some applications.
The height H of this second part 4 of the welding plate 1 and the gaps 13 between the other segments 12 is chosen with respect to the environmental class of the overall concrete structure. As illustrated in FIG. 9, the height may be chosen to allow the normally used reinforcement net 16 to be placed on top of the welding plate with the net extending through the gaps 13. The gaps 13 between the teeth-like segments 9 in the welding plate are chosen in accordance with the net mask size.
A further application is illustrated in FIG 10. The tearing strength of the welding plate 1 according to the invention can be improved by through-going reinforcement steels 17 using the holes 19 placed in the segments 9 in the welding plate 1. Size and exact position of these holes can vary from application to application. If no through-going reinforcement steels are used, the holes 19 add to increased tearing strength allowing the liquid concrete to fill the void.
The thickness of the welding plate 1 is chosen in accordance with the chosen manufacturing method, which is foreseen to be sheet steel bending machine based. With this commonly used production method, a cheaper device can be manufactured, and a more accurate production is possible, compared to welding methods. This increases the quality of the assembly method, since some device uncertainties are removed.
FIG. 11 illustrates a second embodiment of a profile 1' according to the invention, namely a door frame profile. Taking an approach from a sheet metal manufacturing point of view, the design of a door frame profile is done by machining and bending of a piece of sheet metal.
A C-shaped cross section is used as basis for the device, best seen on FIG. 13. With reference to FIG. 11, a first part 3 of the C-shaped profile 1' comprises segments 9 as a row of teeth which have end parts 18 that are bent at an angle relative to the first part 3. The teeth-like segments 9 are included in the geometry for tearing strength purposes, allowing the liquid concrete to fill the void under the bent end part of the sheet metal flange 3. The base 2 of the C-shape is made several times wider than the height of the first 3 and second part 4 of the C-shape.
As illustrated in FIG. 12, in this base flange 2, a pattern of holes, threads or similar can be pre-manufactured in the base 2 for later mounting purposes. The second part of the C-shape is higher, topped by an inward bended third part 11 with large holes 21. This third part 11 is incorporated as a flange in the geometry for tearing strength purposes, allowing the liquid concrete to anchor the door frame profile 1' during the distribution in the concrete panel 15 mould.
Accurate dimensions of the door frame profile would vary from application to application.
By using a cellular foam 22, for example self-adhesive, of EPDM or similar as shown in the cross sectional view of FIG. 14, the pre-manufactured pattern on the inner side 23 is kept free of concrete. Only the teeth-like segment section 24 as well as the inward bended third part 10 is in contact with the concrete, serving as load bearing parts of the profile 1. By choosing a soft cellular profile 22, penetration is possible for screws, rivets or similar.
The design of the door frame profile 1' allows usage on edges of concrete panels 15 as illustrated in more detail in FIG. 15, as well as anywhere on the concrete panel sides. This universal usage is important, since it offers maximum flexibility to the concrete panel designer. Most commonly a door frame profile 1' would be used along one of the concrete panel 15 edges 14, hence making positioning easy since the base part 2 can be placed up against a mould side.
The combination of a sheet metal profile, pre-manufactured by computer numerical machinery, and an accurate positioning of the door frame profile 1' is resulting in very high quality assembly results. The usage in e.g. mounting of doors has proven very well, with low effort in manufacturing the concrete panel 15 and a cost-effective door frame profile 1'.
The profile illustrated as part of a combination may as well be used independently of a substation, as the profile is of a general nature and may be used for other types of concrete panels than the one described in the foregoing.
A method for providing a Compact Secondary Substation 30 comprises moulding two concrete panels 32,33 as walls, providing a foundation plate 31 and a roof 34, erecting the two panel 32,33 on opposite sides of the foundation plate 31, fastening the panels to the foundation plate and connecting the roof 34 to the top of the two panels, providing end gables 40,41 at each end of the substation 30 , wherein at least one of the gables is made of sheet metal parts and comprise a door 42 entrance.
According to a specific embodiment the method the moulding of one of the two concrete panels 32,33 comprises providing a flat bedplate as moulding surface, erect mould sides on the bedplate to define edges of the panel and openings in the panel, fill concrete into the mould and remove the mould sides and the bed plate after concrete hardening. The erect mould sides may for example be chipboard sides.
It should be noted that the above described substation 30 with concrete panels 32,33 as walls is of a general nature and may be constructed without the profile of the invention.

Claims

A compact secondary substation for an electrical apparatus, such as a transformer, comprising a foundation plate, two concrete panels provided as walls on opposites sides of the foundation plate and fastened to the foundation plate, a roof covering the space between the two concrete panels and optionally fastened to the panels, a gable at each end of the substation, wherein at least one of the gables is made of sheet metal parts and comprise a door entrance.
A compact secondary substation according to claim 1, wherein the substation is a transformer house with at least a first and a second room, wherein the first room contains the high voltage part of the electricity and the second room contains the low voltage part of the electricity,
A compact secondary substation according to claim 2, wherein the substation also contains a third room for the transformer.
A compact secondary substation according to claim 2 or 3, wherein the substation comprises ventilation doors integrated in the concrete panels.
A compact secondary substation according to claim 2, 3 or 4, wherein roof of the substation is mounted detachable for the roof to be lifted off when placing the transformer into the substation.
A compact secondary substation according to any preceding claim, wherein the concrete panels of the substation comprise first profiles constituting first metallic welding plates partly integrated in the concrete panels and wherein the foundation plate comprises second profiles for welding connection between the panels and the foundation plate.
A compact secondary substation according to anyone of the claims 1-5, wherein at least one of the concrete panels of the substation comprises a second profile constituting a door frame moulded into the concrete panel.
A compact secondary substation according to claim 6 or 7, where the first profile or the second profile or at least one are generally U shaped or C-shaped with a base and a first and a second part extending laterally from opposite edges of the base to form the legs of the U shaped or C-shaped cross section, wherein the first part has a row of segments resembling a teeth-like structure along the edge of the base and the second part extends into a third part that is bend at an angle relatively to the second part.
A compact secondary substation according to claim 8, wherein the base is flat and the first and the second part extend laterally at a right angle from the base.
A compact secondary substation according to claim 8 or 9, wherein an end part of the segments are bend at an angle.
A compact secondary substation according to anyone of the claims 8-10, wherein each of the segments have at least one hole.
A compact secondary substation according to anyone of the claims 8-11, wherein the gaps between the segments are adapted in accordance with a net mask size of a metal net used for reinforcement of the concrete structure.
A compact secondary substation according to anyone of the claims 8-12, wherein the third part has a row of holes along the base.
A compact secondary substation according to anyone of the claims 8-13, wherein the third part has other segments in a teeth-like structure.
A compact secondary substation according to claim 14, wherein the gaps between the other segments are adapted in accordance with a net mask size of a metal net used for reinforcement of the concrete structure.
A compact secondary substation according to claim 14 or 15, wherein each of the segments has one of the other segments as a counterpart with equal distances from one end of the profile.
A compact secondary substation according to anyone of the claims 8-16, wherein the third part is bent at an angle of between 25 and 65 degrees.
A compact secondary substation according to anyone of the claims 8-18, wherein the base is more than two times wider and less than 5 times wider than the height of the legs of the U-shaped or C-shaped cross section.
A compact secondary substation according to anyone of the claims 8-20, wherein length of the base is at least 2 times larger than its width.
A method for providing a Compact Secondary Substation according to any preceding claim, wherein the method comprises moulding two concrete panels as walls, providing a foundation plate and a roof, erecting the two panel on opposite sides of the foundation plate, fastening the panels to the foundation plate and connecting the roof to the top of the two panels, providing end gables at each end of the substation, wherein at least one of the gables is made of sheet metal parts and comprise a door entrance.
A method according to claim 20, wherein the moulding of one of the two concrete panels comprises providing a flat bedplate as moulding surface, erect mould sides on the bedplate to define edges of the panel and openings in the panel, fill concrete into the mould and remove the mould sides and the bed plate after concrete hardening.