JPS59433A - Steel manhole assembly and its construction - Google Patents

Abstract

PURPOSE:To shorten the period of construction of a steel manhole by a method in which a top manhole unit having an adjustable length is set on plural body manhole units placed on a bottom manhol unit for the lowermost portion. CONSTITUTION:A manhole is made up of a top manhole unit A, a bottom manhole unit C, and plural body manhole units B, and the units B and C have a fixed length but the unit A has a adjustable length. All accesaries are attached to these units and a paint is coated on these units in a factory, and only welding work is made for these units on site. A simple crane 8 and an H-shaped steel base seat 9 are set on the surface of a pit having a larger inside diameter than the outside diameter of the manhole, the unit C is set in the specified place, the unit B is stacked on the unit C in given numbers, the unit A is set on the unit C, and then a mortar grout 2 is placed into the spaces between these units and the pit wall.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a steel manhole assembly and a method of constructing the same.

Conventionally, when constructing a sewage manhole, if it was relatively shallow, the manhole was dug and assembled with ready-made concrete blocks. In the case of deep manholes where ready-made concrete blocks were not sufficient, the manhole was excavated to a specified depth using segments, etc., and the manhole was constructed from the bottom with cast-in-place concrete.

The present invention relates to the latter of the above construction methods, but conventional methods have had the following problems.

()) Due to the large depth, it is necessary to deal with the inflow of groundwater during excavation or pouring concrete IJ-in-place.

(2) When carrying out work in urban areas, etc., a large amount of space is required for the work area.

Additionally, if on-site work is prolonged, there will be a significant impact on surrounding traffic and residents' lives.

(3) Excavation work requires a great deal of labor and requires a long construction period due to limited work space.

(4) Cast-in-place concrete (side walls), etc., limits the area that can be constructed at one time, and furthermore, the construction period becomes longer because the next process cannot proceed until the required minimum strength is achieved. Also, construction management is difficult because it is a cast-in-place concrete IJ.

(5) Because the manhole walls are made of concrete, aging of the walls and deterioration of internal structures such as ramps are likely to occur.
It has a short lifespan.

(6) After constructing the manhole, it is not possible to completely backfill the surrounding excavated area.

The present invention has been made to solve the above-mentioned drawbacks, and aims to shorten the construction period, save work space, and prevent noise pollution to surrounding residents. Still another object of the present invention is to obtain a manhole of arbitrary length depending on the depth of the hole.

In order to achieve the above object, the present invention provides a steel manhole assembly with a manhole of arbitrary length and a method for constructing the same. The present invention will be explained below using the drawings.

FIG. 1 shows an assembled state in which a manhole is constructed to a predetermined length by three combinations of a single head manhole unit (A), a plurality of abdominal manholes (after construction) B, and a single bottom manhole unit C. FIG. 3 is an example cross-sectional view. The length of the head manhole unit A shall be adjusted on site, and the length of the abdomen manhole unit B and bottom manhole unit C shall be fixed, for example, 3 m, 4.5 m.
, 6m. Depending on the depth of the hole into which the manhole assembly is inserted, the number of members (after construction of the abdominal manhole) H or the length of the head manhole unit A may be changed. A
-C, each manhole unit is relatively light in weight so that it can be transported and suspended by a crane.

In addition, in field work, K, so that only welding work is required,
All accessories are installed at the factory and it is in a pre-painted condition (.

FIG. 2 is a plan view and a partial cross-sectional view of each manhole unit embodiment that constitutes the main part of the present invention, (,) is the head manhole unit A, (b) is the head manhole unit A, (b) is the ki ill part (after construction of the manhole) B, (e) shows the bottom manhole unit C. In the figure, reference numeral 5 indicates a manhole unit body made of steel, and the inner surface is coated with anticorrosive paint or made of corrosion-resistant steel material for corrosion resistance.

The manhole unit main body 5 is provided with the following accessories. That is, each manhole unit is provided with a grout socket 6 on its inner peripheral surface, and after the manhole is sunk, the surrounding area is filled with mortar.

Furthermore, a hanging fitting 7 made of SS material, for example, is provided on the outer peripheral surface, and when the manhole unit is hung by a simple crane 8 as shown in FIG. . 10 is a ramp for lifting people up and down, and it is made of stainless steel because it is corrosion resistant.

To fix the gangway 10, support columns 11 made of SS material with anti-corrosion coating are provided and fixed with stainless steel bolts. Reference numeral 12 is a grating made of stainless steel, and based on safety standards, it is installed approximately once every 6 meters. The grating 12 is attached to the manhole unit body 5 by attaching it to a receiving metal fitting 15 welded to the manhole unit body 5 using stainless steel bolts. In addition, grating 12 is equipped with an iC for people to enter and exit.
The opening is about 600a x 400 fins, and is covered with a stainless steel lid when access is required. A groove 14 is provided at the end of the manhole unit body 5 for on-site welding. In addition, the appendix of C) after construction of the bottom manhole shown in Fig. 2 (c) K is shown in Fig. 2 (cL) or (
This is almost the same as b), but in order to make it easier to fix the required number of manhole units in place after joining,
A fixing ring 15 with a serrated cut at the tip is attached, and is embedded in the slime in the hole by the weight of the manhole unit and fixed with high precision. Furthermore, a blind plate 16 is provided, which contributes to reducing the load on the simple crane 8 shown in FIG. 6(c) by utilizing the difference in specific gravity between bentonite and fresh water. In this case, by appropriately balancing the amount of fresh water filled in the manhole with the specific gravity of bentonite, the load on the lifting crane 8 can be freely changed. 17 is a side hole for connecting to the main sewage pipe, and when the building is installed, the lid with a gasket is secured with bolts.

This cover will be removed after grouting and stainless steel bolts will be set in the bolt holes.

An embodiment of the construction method of the present invention is shown in FIG.

First, as shown in Figure 3 (α),
A hole is drilled in the soil 1 with a larger inner diameter of about 00 m to 400 fl, and a simple crane 8 is placed on the surface of the hole as shown in (b).
and a pedestal 9 made of H-beam steel. The bottom manhole unit C is placed in a predetermined position on the pedestal 9 using a simple crane 8 as shown in (C), and then the abdominal manhole unit B is moved to a position where its main bodies overlap on the bottom m manhole unit C. 18 is an on-site joint. The above operation is repeated for a predetermined number of manholes to form a manhole assembly as shown in FIG.

After the work is completed, bottom concrete 6 is placed at the bottom of the manhole, and then mortar grout 2 is applied to the gap between the manhole assembly and the hole wall. After applying anticorrosive coating to the inside of the manhole assembly, a prefabricated inclined shaft block 4 is installed. Figure 4 shows
The details of the on-site joint according to the present invention are shown in (C), (,) shows the case of a joint of equal thickness, and (b) shows the case of a joint of unequal thickness.

That is, the manhole bodies 5a and 5b (5c) are fixed in position by the protective metal fitting 19, the backing ring 20°20α, the stopper 21, and the root spacing bead 22.

As is clear from the above description, according to the present invention, the following remarkable effects can be achieved.

()) Manholes are formed by simply connecting and sinking manhole units manufactured with high precision in a factory on-site, so the construction period is short and only small-scale construction equipment is required.

(2) Since it is basically a combination of manhole units, it is easy to change the depth of the manhole and to connect it with the horizontal pipe.

(3) The work space is small.

(4) Since the accessories are made of stainless steel, there is little deterioration (no maintenance required.

(5) Labor costs for on-site work can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, and FIG. 2 (α). (b) and (e) are a plan view and a partial sectional view of an embodiment of the main part of the present invention, and FIG. 3 ((1), (b), (c) and FIG. 4 (tx)! (b) are sectional views showing an example of the construction method of the present invention. A-i part manhole assembly), B-[IS manhole unit), C-1jI part manhole unit, 8
- Crane, 9-pedestal. Agent Patent Attorney Sanro Kimura Figure 1, Figure 3, Quotient (0) Figure 4 (0) (b)

Claims (2)

[Claims] (1) A steel manhole assembly in which corrosion-resistant manhole units of a certain length are welded and stacked, and the steel manhole assembly has one bottom manhole unit provided at the lowest part. A steel manhole assembly comprising: a plurality of abdominal manhole units placed on the top of the manhole; and one head manhole unit with adjustable length provided on the top. (2) After setting the bottom manhole unit in a predetermined position on the pedestal placed on the surface of the suspension hole using a crane or the like, place the suspended abdominal manhole unit on top of the bottom manhole unit. and join these together.
It is characterized by hanging again and setting it at a predetermined position on the pedestal, repeating the above operation for a predetermined number of abdominal manhole units, and finally placing and joining the head manhole unit whose length has been adjusted in the same way. Construction method of manhole assembly.