GB2080355A

GB2080355A - A Set of Parts for Producing the Floor of a Manhole Shaft in a Sewerage System

Info

Publication number: GB2080355A
Application number: GB8122720A
Authority: GB
Original assignee: GEKATON ABWASSER KORROSIONS SC
Current assignee: GEKATON ABWASSER KORROSIONS SC
Priority date: 1980-07-24
Filing date: 1981-07-23
Publication date: 1982-02-03
Also published as: DE3028093A1; BE889720A; FR2487398A1; DE3028093C2

Abstract

The floor of a circular manhole shaft 20 in a drainage system is formed from a set of prefabricated sector-shaped parts which cooperate to define a part-conical standing surface 16 sloping down to a central part-spherical disk portion 18, two of the parts 1, 2 comprising 90 degree sectors containing respective drainage channels 3, 4. The channels 3, 4 can thus, be arranged in line (as shown) or at an angle, the range of drainage angles being determined by the range of sector angles. In the set shown these are even sectors-three of 90 DEG , one of 45 DEG , one of 221 DIVIDED 2 DEG and two of 111 DIVIDED 4 degrees. Each sector may comprise an open-bottomed shell which is filled on site with light-weight concrete. <IMAGE>

Description

SPECIFICATION A Set of Parts for Producing the Floor of a Shaft in a Sewerage System This invention relates to a set of parts which, when assembled together, form the lower end of a shaft in a sewerage system, having a standing surface next to a sewage channel.

The lower end of an access shaft, for example a manhole, in a sewerage system having a standing surface next to the open sewage channel is at present produced by first forming a bed of concrete at the lower end of the shaft, then placing a ceramic gutter drain in the bed of concrete and then forming benching at each side of the gutter drain to provide standing surfaces with the necessary slope and at the desired level.

The standing surfaces are usually finished with a layer of tiling. Such an operation takes up much time and the labour costs are high. This is especially the case if the two sewers running into and out of the lower end of the shaft are not in line, because in this case the open channel and the tiled benching will have to be tailored to suit the desired angle between the two sewers, making the work harder to undertake and of higher cost.

The present invention aims to provide a set of parts for forming the lower end of a shaft in a sewerage system having a standing surface next to a sewage channel, the separate parts of which may be produced beforehand in a factory and then put together on site so that, as desired, the inlets and outlets for the sewers may be in line or at an angle to one another.

According to the invention, a set of parts which, when assembled together, forms the lower end of a shaft in a sewerage system, having a standing surface next to a sewage channel, is characterised in that the parts comprise readymade segments of a material which is resistant to corrosion, to changes in temperature, to abrasion and to physical loads, two such segments having open channels in them and having a segment angle of 900, while a further group of segments, when put together, has a segment angle of 900.

When employing sets of parts in accordance with the invention, only one such set has to be ordered for the lower end of each shaft of the sewerage system. In order to obtain the desired angle between the inlet and outlet sewers in a shaft, it is only necessary to choose the appropriate orientation of the segments of the set around the shaft without any segments having to be cut to given angles, or without the need for any other costly operation.

In one embodiment of the set of parts in accordance with the invention, the segments may have concave faces adjacent their inner ends, the concave faces preferably being part-spherical.

With such a design, no difficulties will arise in connection with the flow of sewage through the channel, such flow being at the same level and with nothing to obstruct it.

The standing surfaces, which will have an even slope, may be safely used by a sewerage worker during cleaning and inspection operations. The open channel and the part-spherical hollow in the middle of the floor of the shaft may be used with cleaning and inspection apparatus equally as well as in the case of shaft floors which have been grouted by hand.

All the parts of the set may be transported together on a single pallet.

The segments themselves may be of solid construction, and made, for example, of ceramic material, or they may be hollow, for example in the form of shells, thus greatly decreasing the weight which has to be transported and handled on the building site. On site, such parts may then be backed up with light-weight concrete or the like or the segment shells, after being placed in position on the floor of the shaft, may be backed up with cast concrete produced on site.

It will be appreciated that an assembled set of parts in accordance with the present invention has less joints than the hitherto known handproduced, tiled structures, this being especially the case when the two sewers are not in line.

When a set of parts in accordance with the invention has been placed on a bed of mortar at the lower end of the shaft, the small number of joints between the segments are pointed using cement mortar or synthetic resin pointing material, depending on the amount of wear likely to be experienced.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which Figure 1 is a plan of a set of parts in accordance with the invention, assembled together at the lower end of a shaft of a sewerage system, Figures 2 and 3 are sectional views taken on the lines Il-Il and Ill-I II, respectively, of Figure 1,and Figure 4 is a view similar to Figure 1, but showing a different orientation of the segments of the set of parts for the purpose of joining two sewers which are inclined at an angle to one another.

The set of parts shown in Figures 1 to 3 is employed for joining two aligned sewer pipes 5 and 6 at the lower end of a shaft 20 of a sewerage system. The set of parts comprises three 900 segments 1, 2 and 7, a 450 segment 8, a 22.50 segment 9 and two 11.250 segments 10 and 11. In the clockwise direction, as viewed in Figure 1, these segments are arranged in the sequence 1, 11, 10, 9, 8, 2 and 7, with the result that the segments 1 and 2 are disposed diametrically opposite one another with open, radially-disposed channels 3 and 4 in the segments 1 and 2, respectively, aligned with one another. The sewer pipes 5 and 6 are joined to the radially outer ends of the channels 3 and 4, respectively, employing shaft joints.

By changing the sequence of the segments, it is possible to join sewer pipes which, instead of being aligned with one another as in Figure 1, are inclined with respect to one another. Figure 4 shows one such arrangement in which, in the clockwise direction, the segments are arranged in the sequence 1, 7, 10, 1 2, 9 and 8, with the result that the open channels 3 and 4 are inclined to one another at an angle of 22.5" for the purpose of joining together two pipes 5a and 6a, which are also inclined to one another at an angle of 22.5 .

It will be appreciated that by using different sequences of the segments, the set of parts shown in Figure 1 may be employed to join together sewer pipes inclined to one another at a large number of different angles.

Figures 2 and 3 show that the segments are of hollow construction, the shells 12 of the segments being made of a material which is resistant to corrosion, to changes in temperature, to abrasion and to physical loads and which is slip-proof. Suitable materials are, for example, stonewear, synthetic resin concrete or a deep drawn synthetic resin plate. Bedding concrete 14 is laid on the floor 13 of the shaft 20. The segment shells 12 are filled with lighweight concrete 1 5 which may be produced on site or at a remote location.

At their radially inner side the segments have concave faces 18, preferably of part-spherical shape, and each segment has a standing surface 1 6 which slopes donwardly in the direction towards the radially inner end of the segment.

Of course, segments of different radii would be employed for assembly at the lower ends of shafts having a different diameter from the shaft 20 shown in the drawings.

Claims

1. A set of parts which, when assembled together, forms the lower end of a shaft in a sewerage system, having a standing surface next to a sewage channel, which parts comprise readymade segments of a material which is resistant to corrosion, to changes in temperature, to abrasion and to physical loads, two such segments having ç open channels in them and having a segment angle of 90 , while a further group of segments, when put together, has a segment angle of 900. 9

2. A set of parts as claimed in claim 1, in which the segments have part-spherical hollows towards their inner ends.

3. A set of parts as claimed in claim 1 or claim 2, in which the segments are in the form of hollow shells.

4. A set of parts as claimed in claim 1 substantially as herein described with reference to, and as illustrated in, the accompanying drawings.