IES60337B2

IES60337B2 - Improvements in manholes

Info

Publication number: IES60337B2
Authority: IE
Inventors: John Condron
Original assignee: John Condron
Priority date: 1993-03-08
Filing date: 1994-02-23
Publication date: 1994-06-29
Also published as: IES940170A2

Description

IMPROVEMENTS IN MANHOLES This invention relates to improvements in manholes. In particular, it relates to manhole components and manhole housings formed from such components.

Manholes provide access to underground pipes such as, for example, water pipes. Manholes are currently constructed in situ from bricks and mortar when the pipes are being laid. However, this method, of constructing manholes is time-consuming and therefore expensive.

It is therefore an object of the invention to provide manhole components which facilitate the construction of manhole housings.

Accordingly, the present invention provides a base component for a manhole housing, the component comprising a floor with a side wall extending therefwsa to an open end, the floor having channel means, and the side wall having a port in communication with the channel means, the port being capable of receiving an «e inlet or outlet pipe; and the open end of the base component having mating means for coaxial engagement with a manhole housing construction unit having co-operating mating means.

The invention also provides a construction unit ’ for a manhole housing for use with a base component according to the invention, the unit comprising an J open-ended chamber having means for descending and ascending within the chamber and mating means at each end for coaxial engagement with the base component or another construction unit.

The invention further provides a manhole housing comprising a base component according to the invention and a plurality of construction units according to the invention, the base component forming the base of the housing and the construction units being arranged on top of the base component so that each adjacent construction unit is in coaxial and sealing engagement with one another and the construction unit adjacent the base component is in coaxial and sealing engagement therewith.

Preferably, the base component and construction unit are each made of concrete. The side wall of the base component has an outer surface which is preferably octagonal in cross-section and an inner surface which is preferably circular in cross-section. The construction unit preferably has a circular cross-sectional configuration.

The means for descending and ascending movement within the chamber of the construction unit are preferably precast rungs.

The mating means on the base component and construction unit preferably comprise a mutually co-operating projection and recess.

In a further aspect, the invention provides a method for constructing a manhole housing, which method comprises providing a base component and a plurality of construction units according to the invention; placing the base component in the desired location; placing one of the construction units on top of the base component so that it is in coaxial and sealing engagement therewith; and placing further construction units one at a time on top of the construction unit adjacent the base component, so that each adjacent construction unit is in coaxial and sealing engagement with one another.

The invention will be further described by way of example with reference to the accompanying drawings, in which: Figure 1 is a perspective view of one embodiment of a base component according to the invention; Figure 2 is a perspective view of the base component of Figure 1 with one construction unit according to the invention; and Figure 3 is a front elevational view of a manhole housing according to the invention.

Referring now to the drawings, and in particular to Figure 1, there is shown a base component 10 for a manhole housing according to the invention. The base component 1 © has a floor 11 and a side wall 12 extending therefrom to an open end 13. The floor 11 has a 3© channel 14 which may be branched as shown in the present embodiment. It will be appreciated that the channel 14 may have a variety of shapes. For example, it may be linear or 0, X or Y-shaped in plan. The diameter of the channel 14 is preferably in the range of frcraa 150 s® to 60© The side wall 12 has an inner surface 15, an outer surface 16 and ports 17 in the side wall 12 in fluid communication with the channel 14. Each port 17 is formed with a socket (not shown) so that it may receive an inlet or outlet pipe 20 which has a corresponding spigot.

The open end 13 of the base component 10 has a projection in the form of a spigot 18 which engages with 10 a corresponding recess in the form of a socket (not shown) of a construction unit 30 (see Figure 2). A rubber gasket 50 is provided around the spigot 18 so that the spigot/socket joint is fluid-tight.

To avoid cracks being present in the spigot following manufacture, it is preferable to use a rotating former which would provide better compaction and a smooth finish. In addition, it has been found that during removal of the spigot former from the spigot during manufacture, rotation of the former helps to eliminate the vacuum between the concrete and the former thus avoiding any cracks in the spigot.

The inner surface 15 of the base component 10 is preferably circular in cross-section and the outer surface 16 is preferably octagonal in cross-section as in the embodiment shown.

The base component 10 is preferably made of concrete and has an overall height which is preferably in the range of from 750 mm to 1,250 mm, this being equivalent to an effective height of from 600 «a to 1,100 ma. The internal diameter of the base component 10 is preferably in the range of from 900 » to 1,500 ®sa.

Figure 2 is a perspective view of the base component 10 shown in Figure 1 with a construction unit 30 connected thereto. The construction unit 30 is ΊΟ preferably made of concrete and comprises an open-ended chamber 31 having a first end 33 and a second, end 34. The chamber 31 is preferably circular in cross-section as in the embodiment shown. The chamber 31 is provided with precast rungs 32 which are preferably formed from aluminium and coated with a plastics material, such as polyethylene. The rungs 32 are advantageously approximately 355 mm wide and are spaced approximately 250 mm apart, providing a uniform step interval in each construction unit 30. The plastics coating on the rungs 32 is resistant to virtually all media and also prevents sparking when contacted with iron-mounted footwear. The first end 33 of the construction unit 30 is provided with a socket (not shown) for releasable engagement with the spigot 18 of the base component 10 or a spigot of a further construction unit 30. The second end 34 is provided with a spigot 35 for releasable engagement with the socket of an adjacent construction unit 30. A gasket 50 is also provided in each joint to ensure a fluid-tight seal.

The construction unit 30 has a height which is preferably in the range of from 250 mm to 1,000 rasa with a wall thickness which is preferably in the range of from 95 a® to 155 mm and an internal diameter which is preferably in the range of from 900 mm to 1,500 sa.

Figure 3 is a front elevational view of a manhole housing 40 according to the invention canprising the base component 10 and three construction units 30 as described above. The construction unit 30 connected to the base component 10 has a height of approximately In, the adjacent unit 30 has a height of approximately 0.5m and the upper unit 30 has a height of approximate^ ' 0.25m.

The base component 10 and each construction unit are designed for spigot/socket jointing with a gasket in each joint to ensure a fluid-tight seal. Once the base component 10 is positioned in the manhole, the housing 40 can be constructed by adding on the required number of construction units 30. The construction of the manhole housing 40 from the base component 10 and the construction units 30 is facilitated by the design of the joints and the fact that each gasket 50, which is coated with a lubricant, functions as a sliding ring so that the alignment of the base component 10 and the construction units 30 is fast and efficient. Of course, the units 30 are aligned in such a way that the rungs 32 are in alignment, thereby forming a ladder in the manhole housing 40.

The construction units 30 may be reinforced if necessary. To complete the manhole housing 40, a reinforced concrete cover (not shown) is placed on the top construction unit 30. The cover has a socketed base which allows a rubber gasket joint to the top construction unit 30.

The invention thus provides manhole components which allow easy and efficient construction of manhole housings.

The invention is not limited to the embodiments described herein which may be modified or varied without departing from the scope of the invention.

Claims

CLAIMS:

1. A base component for a manhole housing, the component comprising a floor with a side wall extending 5 therefrom to an open end, the floor having channel Means, and the side wall having a port in communication with the channel means, the port being capable of receiving an inlet or outlet pipe; and the open end of the base component having mating means for coaxial 10 engagement with a manhole housing construction unit having co-operating mating means.

2. A base component according to claim 1, in which the mating means comprise a projection and recess in the 15 form of a spigot and socket, respectively, the spigot preferably having a gasket disposed thereon to provide a fluid-tight seal and the base component preferably having an effective height in the range of from 600 mm to 1,100 mm and an internal diameter in the range of 20 from 900 mm to 1,500 mm.

3. A construction unit for a manhole housing for use with a base coraiponent according to claim 1 or 2, the unit comprising an open-ended chamber having means for 25 descending and ascending within the chamber and mating means at each end for coaxial engagement with the base component or another construction unit, and the construction unit preferably having an effective height in the range of from 250 mm to 1,000 mm and an internal 3Ό diameter in the range of from 900 mm to 1,500 ».

4. A manhole housing comprising a base component according to claim 1 or 2 and a plurality of construction units according to claim 3, the base component forming the base of the housing and the construction units being arranged on top of the base component so that each adjacent construction unit is in coaxial and sealing engagement with one another and the

5. Construction unit adjacent the base component is in coaxial and sealing engagement therewith, the base component and construction units preferably being made of concrete. Ί0 5. A method for constructing a manhole housing, which method comprises providing a base component according to claim 1 or 2 and a plurality of construction units according to claim 3; placing the base component in the desired location; placing one of 15 the construction units on top of the base component so that it is in coaxial and sealing engagement therewith; and placing further construction units one at a time on top of the construction unit adjacent the base component, so that each adjacent construction unit is in 20 coaxial and sealing engagement with one another. F. R. KELLY & CO.