EP0578445A1 - Drainage systems - Google Patents
Drainage systems Download PDFInfo
- Publication number
- EP0578445A1 EP0578445A1 EP93305193A EP93305193A EP0578445A1 EP 0578445 A1 EP0578445 A1 EP 0578445A1 EP 93305193 A EP93305193 A EP 93305193A EP 93305193 A EP93305193 A EP 93305193A EP 0578445 A1 EP0578445 A1 EP 0578445A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- membrane
- drainage
- module
- drainage channel
- side wall
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C11/00—Details of pavings
- E01C11/22—Gutters; Kerbs ; Surface drainage of streets, roads or like traffic areas
- E01C11/224—Surface drainage of streets
- E01C11/227—Gutters; Channels ; Roof drainage discharge ducts set in sidewalks
- E01C11/228—Gutters for porous pavings
Definitions
- the present invention relates to a surface drainage system and, more particularly, to a modular system for creating a network of drainage channels under an area which is surfaced with a porous medium such as tarmacadam.
- surface drainage is often provided by the use of a network of interconnecting U shaped channels which are laid with an appropriate fall so that the water collected flows away.
- the water is collected through a cover, for example a cast iron or galvanised grating which is located over the open tops of the drainage channels flush with the surface.
- a waterproof membrane may be laid.
- a flexible membrane of plastics or rubber as used for damp proof courses in construction is typically employed.
- This membrane must be interrupted at the drainage channels in order to allow water collected on the membrane to flow into the channels.
- a system suffers from the technical problem that the edges of the waterproof membrane are liable to move when the slab of surfacing material is cast on top of it or when paving slabs or the like are laid on top of it. This allows water to escape beneath the membrane into the pre-cast slab below significantly reducing the efficiency of drainage.
- a modular drainage system in accordance with the invention is characterised in that a membrane drain module is interposed, in use, between the drainage channel module and the cover, the membrane drain module comprising two spaced side walls defining openings therein, a bottom of each side wall adapted to engage with the top of a corresponding side wall of the drainage channel module in order to clamp an edge of a waterproof membrane therebetween.
- Such a system is advantageous in that the standard locking system with rotatable locking bar can still be used as a locking means to connect the entire assembly together.
- the locking bolt provided must be lengthened only by the depth of the membrane drain module and therefore this system can readily be implemented using standard parts for the channel module and cover.
- the membrane drain module is preferably formed of polymer concrete in which the openings through which water can flow into the drainage channel can, in a preferred embodiment, be formed therein by means of a crenellated bottom surface of each side wall. In this way the module is relatively simple to cast using a two part mould.
- the surface drainage system consists of a network of open-top drainage channels.
- these channels are formed of inter-locking modules cast from polymer concrete such as the channel module 2 shown in the drawings. Since the principle of the present drainage system can be adequately described by reference to one section of the overall system, the following description relates to only a single channel module. However, it will be appreciated that a system will require many modules to be laid to define a network of interconnecting channels, the configuration of which will depend on the lie of the land to be drained and the rate at which water must be removed in a manner with which architects and planners skilled in this area will be familiar.
- Each drainage channel module is U shaped with parallel side walls 8, 10 and a smoothly rounded internal base in order to assist fluid flow.
- Ledges 6 are formed along the inside faces of the side walls at the top.
- a cover in the form of sections of cast iron or galvanised grid or grating 4 is seated directly on the ledges 6.
- the cover is held in position by means of locking bolts 12.
- the shaft of each bolt passes through an opening 14 in the centre of each cover section and has a head 20 which rests against the surface of the cover 4.
- One end of the bolt is threaded so that a locking bar 16 can be secured to it.
- Inwardly facing spaced recesses 18 are provided in each side wall 8, 10 of the drainage channel module beneath the ledges 6.
- These recessess are arcuate in plan in order to receive the ends of the locking bar when it is rotated in position (by rotating the bolt 12 by means of a head 20 from the surface) in order to rotate the locking bar from a position in which it lies parallel to the channel into a position in which its ends are received in the recesses 18.
- the drainage system is essentially conventional.
- an upper membrane drain module 22 is interposed between the grid 4 and the channel 2.
- the only variation of the standard components necessary to accommodate the interposition of the module 22 is the need to use longer than normal bolts 12 to allow for the extra distance between the grid and the recesses 18.
- the membrane drain module 22 is also cast from polymer concrete in modular sections which may be of the same standard lengths as the channel modules.
- Each module consists of two parallel side walls 24, 26 which are held relative to each other by means of cross members 28, 30.
- the cross members 28 at each end of the module and in the centre are relatively narrow.
- the two cross members 30, which are intended to be positioned in alignment with the holes 14 in the grid sections 4, are wider in order to accommodate a through-bore 32 necessary to receive the bolt 12.
- the tops of the side walls 24, 26 are formed with ledges 34 similarly configured to the ledges 6 in the the top of drainage module 2 so that the cover 4 is able to be seated in the top of the membrane drain module.
- the bottoms of each side wall 24, 26 have an outwardly projecting flange 38 to provide a larger bottom surface area. This bottom surface is crenellated in order to define a series of U-shaped channels 36 along each side.
- the base of the module 22 cooperates in use, with the top of the side walls of the drainage module 2 in order to clamp therebetween edges of a waterproof membrane 40.
- FIG 3 an alternative embodiment of the base of the side walls 24, 26 of the membrane drain module is illustrated.
- an inwardly positioned, downwardly depending flange 42 is provided which is sized to seat on the corresponding ledge 6.
- this flange 42 is not continuous but is only provided on those portions of the side wall which engage with the top of the drainage channel module. This provides a zig-zag space between the base of the side walls of the membrane drain and the top of the drainage channel which more securely retains the membrane 40 in position and resists withdrawal of the membrane 40 when it is subject to lateral forces.
- the drainage channels are laid as normal in the required configuration. Concrete is then poured around the drainage channels in order to create a pre-cast slab.
- the waterproof membrane 40 is then laid over the pre-cast slab. Where the membrane 40 abuts a drainage channel it is cut so as to leave a small overlap (as shown in Figure 2) with the upper edge of the channel. The edges of the membrane 40 cannot be left too long or they would impede the flow of water in the channel.
- the grids 4 together with the associated bolts 12 and locking bar are assembled to the membrane drain modules prior to installation. The assembly of the drainage system is then completed by positioning the membrane modules 22 on top of each drainage channel module such that the edges of the waterproof membrane are sandwiched between the top surface of each side wall of the drainage channel and the corresponding bottom surface of each side wall of the membrane drain module 22.
- the drainage system is completed by rotating the bolts by their heads 20 in order to bring the locking bars 16 into engagement with the corresponding recesses 18 in the drainage channels.
- edges of the waterproof membrane 40 are thus securely clamped in position and cannot move away from the drainage channels when the upper slab of surfacing material is cast around the completed drainage system, or when paving blocks are laid.
Landscapes
- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Sewage (AREA)
Abstract
A drainage system is made up of drainage channel modules (2) which are substantially U-shaped. A waterproof membrane (40) is laid adjacent to the drainage channels. Cut edges of the membrane overlap the edges of the side walls of the channel. Membrane drain modules (22) are located above the drainage channel modules so that the bottom surface of each side wall of the membrane drain modules clampingly engages the waterproof membrane against the upper edge of the side wall of the drainage channel modules. The drainage system is completed by means of cast iron or galvanised grid covers (4) which are secured to the drainage channel modules (2), thereby also holding the membrane drain modules and membrane in place, by means of bolts (12) carrying rotatable locking bars (16). Water collecting on the waterproof membrane (40) passes into the drainage channel by means of openings (36) along the bottom of each side wall of the membrane drain module.
Description
- The present invention relates to a surface drainage system and, more particularly, to a modular system for creating a network of drainage channels under an area which is surfaced with a porous medium such as tarmacadam.
- For large areas where efficient drainage of surface water is required, such as roadways, car parks, shopping precincts, farm yards and airports, surface drainage is often provided by the use of a network of interconnecting U shaped channels which are laid with an appropriate fall so that the water collected flows away. The water is collected through a cover, for example a cast iron or galvanised grating which is located over the open tops of the drainage channels flush with the surface.
- However, if the surrounding surfacing material is itself porous, some of the water will not be collected on the surface to flow through the grating into the channels but will soak through the surface and therefore never enter the drainage system. To prevent water draining into the layers beneath the surface, a waterproof membrane may be laid. A flexible membrane of plastics or rubber as used for damp proof courses in construction is typically employed.
- This membrane must be interrupted at the drainage channels in order to allow water collected on the membrane to flow into the channels. However, such a system suffers from the technical problem that the edges of the waterproof membrane are liable to move when the slab of surfacing material is cast on top of it or when paving slabs or the like are laid on top of it. This allows water to escape beneath the membrane into the pre-cast slab below significantly reducing the efficiency of drainage.
- To allow water to pass into the channel from the membrane, apertures are needed in the sides of the channel. This prevents the use of conventional polymer concrete U-shaped channels such as those marketed by Aco Polymer Products Limited as part of their ACO DRAIN (Registered Trade Mark) system.
- In order to overcome these technical problems, a modular drainage system in accordance with the invention is characterised in that a membrane drain module is interposed, in use, between the drainage channel module and the cover, the membrane drain module comprising two spaced side walls defining openings therein, a bottom of each side wall adapted to engage with the top of a corresponding side wall of the drainage channel module in order to clamp an edge of a waterproof membrane therebetween.
- Such a system is advantageous in that the standard locking system with rotatable locking bar can still be used as a locking means to connect the entire assembly together. The locking bolt provided must be lengthened only by the depth of the membrane drain module and therefore this system can readily be implemented using standard parts for the channel module and cover.
- The membrane drain module is preferably formed of polymer concrete in which the openings through which water can flow into the drainage channel can, in a preferred embodiment, be formed therein by means of a crenellated bottom surface of each side wall. In this way the module is relatively simple to cast using a two part mould.
- Two embodiments of the present invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which:
- Figure 1 shows a diagrammatic exploded view of the parts of the drainage system;
- Figure 2 is a longitudinal cross sectional view through an assembled drainage system; and
- Figure 3 is a detail of the right hand side of the coupling between a modified embodiment of the membrane drain module and the drainage channel module.
- The surface drainage system consists of a network of open-top drainage channels. In current practice, these channels are formed of inter-locking modules cast from polymer concrete such as the
channel module 2 shown in the drawings. Since the principle of the present drainage system can be adequately described by reference to one section of the overall system, the following description relates to only a single channel module. However, it will be appreciated that a system will require many modules to be laid to define a network of interconnecting channels, the configuration of which will depend on the lie of the land to be drained and the rate at which water must be removed in a manner with which architects and planners skilled in this area will be familiar. - Each drainage channel module is U shaped with
parallel side walls Ledges 6 are formed along the inside faces of the side walls at the top. - Normally a cover in the form of sections of cast iron or galvanised grid or grating 4 is seated directly on the
ledges 6. The cover is held in position by means of lockingbolts 12. The shaft of each bolt passes through anopening 14 in the centre of each cover section and has ahead 20 which rests against the surface of thecover 4. One end of the bolt is threaded so that alocking bar 16 can be secured to it. Inwardly facingspaced recesses 18 are provided in eachside wall ledges 6. These recessess are arcuate in plan in order to receive the ends of the locking bar when it is rotated in position (by rotating thebolt 12 by means of ahead 20 from the surface) in order to rotate the locking bar from a position in which it lies parallel to the channel into a position in which its ends are received in therecesses 18. This system of using a toggle bar to lock a cover to a channel module is described in more detail in EP-B-81741. - As so far described the drainage system is essentially conventional. However, in the present system an upper
membrane drain module 22 is interposed between thegrid 4 and thechannel 2. The only variation of the standard components necessary to accommodate the interposition of themodule 22 is the need to use longer thannormal bolts 12 to allow for the extra distance between the grid and therecesses 18. - The
membrane drain module 22 is also cast from polymer concrete in modular sections which may be of the same standard lengths as the channel modules. Each module consists of twoparallel side walls cross members cross members 28 at each end of the module and in the centre are relatively narrow. The twocross members 30, which are intended to be positioned in alignment with theholes 14 in thegrid sections 4, are wider in order to accommodate a through-bore 32 necessary to receive thebolt 12. - The tops of the
side walls ledges 34 similarly configured to theledges 6 in the the top ofdrainage module 2 so that thecover 4 is able to be seated in the top of the membrane drain module. The bottoms of eachside wall flange 38 to provide a larger bottom surface area. This bottom surface is crenellated in order to define a series of U-shapedchannels 36 along each side. The base of themodule 22 cooperates in use, with the top of the side walls of thedrainage module 2 in order to clamp therebetween edges of awaterproof membrane 40. - In Figure 3 an alternative embodiment of the base of the
side walls flange 42 is provided which is sized to seat on thecorresponding ledge 6. Where the base is crenellated thisflange 42 is not continuous but is only provided on those portions of the side wall which engage with the top of the drainage channel module. This provides a zig-zag space between the base of the side walls of the membrane drain and the top of the drainage channel which more securely retains themembrane 40 in position and resists withdrawal of themembrane 40 when it is subject to lateral forces. - In use, the drainage channels are laid as normal in the required configuration. Concrete is then poured around the drainage channels in order to create a pre-cast slab. The
waterproof membrane 40 is then laid over the pre-cast slab. Where themembrane 40 abuts a drainage channel it is cut so as to leave a small overlap (as shown in Figure 2) with the upper edge of the channel. The edges of themembrane 40 cannot be left too long or they would impede the flow of water in the channel. Thegrids 4 together with the associatedbolts 12 and locking bar are assembled to the membrane drain modules prior to installation. The assembly of the drainage system is then completed by positioning themembrane modules 22 on top of each drainage channel module such that the edges of the waterproof membrane are sandwiched between the top surface of each side wall of the drainage channel and the corresponding bottom surface of each side wall of themembrane drain module 22. - Once the position of the
membrane 40 has been checked, the drainage system is completed by rotating the bolts by theirheads 20 in order to bring thelocking bars 16 into engagement with thecorresponding recesses 18 in the drainage channels. - The edges of the
waterproof membrane 40 are thus securely clamped in position and cannot move away from the drainage channels when the upper slab of surfacing material is cast around the completed drainage system, or when paving blocks are laid. - In use all the water that passes through the porous upper layer is collected at the surface of the
waterproof membrane 40 and flows through theopenings 36 into the drainage system.
Claims (8)
- A drainage system comprising a substantially U-shaped drainage channel module (2) a cover (4) for a top of the drainage channel module, and means (12, 14, 16, 18, 20) for locking the cover to the drainage channel module, characterised in that a membrane drain module (22) is interposed, in use, between the drainage channel module (2) and the cover, the membrane drain module (22) comprising two spaced side walls (24, 26) defining openings (36) therein, a bottom of each side wall (24, 26) adapted to engage with the top of a corresponding side wall (8, 10) of the drainage channel module (2) in order to clamp an edge of a waterproof membrane (40) therebetween.
- A drainage system is claimed in claim 1, wherein the openings (36) are formed by means of a crenellated bottom surface of at least one side wall (24, 26).
- A drainage system as claimed in any one of the preceding claims, wherein the membrane drain module (22) is cast from polymer concrete.
- A drainage system as claimed in any one of the preceding claims, wherein the side walls (24, 26) of the membrane drain module comprise a flange (42) which engages with a corresponding ledge (6) at the top of the corresponding side wall of the drainage channel module (2).
- A drainage system is claimed in any one of the preceding claims, wherein the side walls (24, 26) of the membrane drain module (22) are interconnected by means of spaced cross members (28, 30).
- A drainage system is claimed in claim 5, wherein at least some of the cross members (30) are formed with through bores defined therein in order to allow passage of a locking bolt (12) of the locking means (12, 13, 16, 20).
- A drainage system as claimed in any one of the preceding claims, wherein the locking means comprise bolts (12) which each pass from a cover (4) into a drainage module channel (2) below, each bolt carrying a rotatable locking bar (16) the ends of which are engageable with recesses (18) defined in the side walls of the drainage channel module.
- A membrane drain module for use in a drainage system in accordance with any one of the preceding claims.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9214309A GB2268528A (en) | 1992-07-06 | 1992-07-06 | Drainage system |
GB9214309 | 1992-07-06 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0578445A1 true EP0578445A1 (en) | 1994-01-12 |
Family
ID=10718267
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP93305193A Withdrawn EP0578445A1 (en) | 1992-07-06 | 1993-07-02 | Drainage systems |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0578445A1 (en) |
GB (1) | GB2268528A (en) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998011300A1 (en) * | 1996-09-12 | 1998-03-19 | Jagiecco Jacek | The dewatering flume |
EP0863258A2 (en) * | 1997-03-04 | 1998-09-09 | Karl Kortmann | Pavement construction with a plane-sealing |
FR2791715A1 (en) | 1999-03-31 | 2000-10-06 | Nicoll Raccords Plastiques | Thermoplastic duct component has twin extruded walls - smooth inner wall and outer corrugated one |
WO2001094704A1 (en) * | 2000-06-08 | 2001-12-13 | Aco Severin Ahlmann Gmbh & Co. Kg | Cover piece for a drainage channel |
US6945733B2 (en) * | 2001-05-04 | 2005-09-20 | Aco Severin Ahlmann Gmbh & Co. Kg | Cover for a drainage device |
WO2012031729A1 (en) * | 2010-09-06 | 2012-03-15 | Mea Bausysteme Gmbh | Slotted cover for a channel body |
US8474068B2 (en) | 2010-01-05 | 2013-07-02 | Noble Company | Trench shower drain |
CN105133721A (en) * | 2015-09-25 | 2015-12-09 | 芜湖弛科排水材料贸易有限公司 | Double-branch finished drainage ditch |
EP2508685B1 (en) * | 2011-04-06 | 2020-04-29 | Easy Sanitary Solutions B.V. | Clamping construction for drain |
WO2021099488A1 (en) | 2019-11-19 | 2021-05-27 | Technische Universiteit Delft | Urban artificial wetland and method for building such an urban artificial wetland |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2342374B (en) * | 1998-09-15 | 2002-07-24 | Allpipe Ltd | Drainage channel covers |
CN103572828B (en) * | 2013-11-11 | 2017-04-05 | 靳阳阳 | Automatic safe well lid |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0081741A1 (en) * | 1981-12-12 | 1983-06-22 | ACO Severin Ahlmann GmbH & Co. KG | Drainage channel with cover member |
DE8706254U1 (en) * | 1987-04-30 | 1987-07-23 | Passavant-Werke AG, 6209 Aarbergen | Drainage channel |
DE8707941U1 (en) * | 1987-06-04 | 1987-10-15 | Birco Baustoffwerk GmbH, 7570 Baden-Baden | Concrete component for the production of connected channels |
EP0371917A1 (en) * | 1988-11-30 | 1990-06-06 | Poly-Bauelemente AG | Capping frame for a drainage channel |
-
1992
- 1992-07-06 GB GB9214309A patent/GB2268528A/en not_active Withdrawn
-
1993
- 1993-07-02 EP EP93305193A patent/EP0578445A1/en not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0081741A1 (en) * | 1981-12-12 | 1983-06-22 | ACO Severin Ahlmann GmbH & Co. KG | Drainage channel with cover member |
DE8706254U1 (en) * | 1987-04-30 | 1987-07-23 | Passavant-Werke AG, 6209 Aarbergen | Drainage channel |
DE8707941U1 (en) * | 1987-06-04 | 1987-10-15 | Birco Baustoffwerk GmbH, 7570 Baden-Baden | Concrete component for the production of connected channels |
EP0371917A1 (en) * | 1988-11-30 | 1990-06-06 | Poly-Bauelemente AG | Capping frame for a drainage channel |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998011300A1 (en) * | 1996-09-12 | 1998-03-19 | Jagiecco Jacek | The dewatering flume |
EP0863258A2 (en) * | 1997-03-04 | 1998-09-09 | Karl Kortmann | Pavement construction with a plane-sealing |
EP0863258A3 (en) * | 1997-03-04 | 1999-01-20 | Karl Kortmann | Pavement construction with a plane-sealing |
FR2791715A1 (en) | 1999-03-31 | 2000-10-06 | Nicoll Raccords Plastiques | Thermoplastic duct component has twin extruded walls - smooth inner wall and outer corrugated one |
US7008137B2 (en) | 2000-06-08 | 2006-03-07 | Aco Severin Ahlmann Gmbh & Co., Kg | Cover for a drainage arrangement and a method of producing such an arrangement |
WO2001094704A1 (en) * | 2000-06-08 | 2001-12-13 | Aco Severin Ahlmann Gmbh & Co. Kg | Cover piece for a drainage channel |
US6945733B2 (en) * | 2001-05-04 | 2005-09-20 | Aco Severin Ahlmann Gmbh & Co. Kg | Cover for a drainage device |
US8474068B2 (en) | 2010-01-05 | 2013-07-02 | Noble Company | Trench shower drain |
WO2012031729A1 (en) * | 2010-09-06 | 2012-03-15 | Mea Bausysteme Gmbh | Slotted cover for a channel body |
EP2508685B1 (en) * | 2011-04-06 | 2020-04-29 | Easy Sanitary Solutions B.V. | Clamping construction for drain |
CN105133721A (en) * | 2015-09-25 | 2015-12-09 | 芜湖弛科排水材料贸易有限公司 | Double-branch finished drainage ditch |
WO2021099488A1 (en) | 2019-11-19 | 2021-05-27 | Technische Universiteit Delft | Urban artificial wetland and method for building such an urban artificial wetland |
NL2024264B1 (en) | 2019-11-19 | 2021-08-18 | Univ Delft Tech | Urban artificial wetland and method for building such an urban artificial wetland. |
Also Published As
Publication number | Publication date |
---|---|
GB2268528A (en) | 1994-01-12 |
GB9214309D0 (en) | 1992-08-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0578445A1 (en) | Drainage systems | |
US20060239773A1 (en) | Trench drain frame and grate assembly | |
DE4307260C2 (en) | Cable duct element | |
US4986693A (en) | Roadway water drainage installation | |
US4010896A (en) | Modular liquid collection system for railroad roadbeds | |
NZ208269A (en) | Insulating panel: edge channel open to surface channels | |
DE60317611T2 (en) | Wide drainage channel | |
DE9416319U1 (en) | Channel system | |
IES67878B2 (en) | A drainage installation for roads | |
JPH0712580U (en) | Gutter drain pipe | |
DE20206800U1 (en) | Infrastructure Channel | |
JPH01287324A (en) | Drainage structure of asphalt pavement concrete floor slab | |
GB2315792A (en) | Kerb drainage system | |
GB2301132A (en) | Drainage unit | |
US4655435A (en) | Cattle guard | |
JP2018197460A (en) | Drain port structure of permeable pavement | |
GB2305200A (en) | Drainage unit | |
JPH11128867A (en) | Waste disposal plant | |
JPH0739986Y2 (en) | Drainage | |
JPH02125041A (en) | Composite measure | |
RU2733135C1 (en) | Open channel with drainage system for liquid discharge | |
JPH057774U (en) | Adjustment tank for rainwater penetration | |
JP3047285U (en) | Precast concrete culvert and drainage structure using it | |
JPS627736Y2 (en) | ||
EP1520943A2 (en) | Surface drainage system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE DE GB IT NL |
|
17P | Request for examination filed |
Effective date: 19940610 |
|
17Q | First examination report despatched |
Effective date: 19950714 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 19951125 |