GB2270647A - Apparatus and method for moulding of reinforced concrete ring segments - Google Patents
Apparatus and method for moulding of reinforced concrete ring segments Download PDFInfo
- Publication number
- GB2270647A GB2270647A GB9220041A GB9220041A GB2270647A GB 2270647 A GB2270647 A GB 2270647A GB 9220041 A GB9220041 A GB 9220041A GB 9220041 A GB9220041 A GB 9220041A GB 2270647 A GB2270647 A GB 2270647A
- Authority
- GB
- United Kingdom
- Prior art keywords
- molding plate
- concrete
- lower mold
- upper molding
- steel form
- 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- Withdrawn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
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
- B28B1/24—Producing shaped prefabricated articles from the material by injection moulding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/245—Curing concrete articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/245—Curing concrete articles
- B28B11/246—Underwater curing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B7/00—Moulds; Cores; Mandrels
- B28B7/40—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material
- B28B7/44—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material for treating with gases or degassing, e.g. for de-aerating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B7/00—Moulds; Cores; Mandrels
- B28B7/40—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material
- B28B7/46—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material for humidifying or dehumidifying
Landscapes
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Structural Engineering (AREA)
- Moulds, Cores, Or Mandrels (AREA)
- Lining And Supports For Tunnels (AREA)
Abstract
Apparatus for forming a reinforced ring concrete segment includes a steel form device (20) comprising lower mold (21), porous upper molding plate (22) screwed to the lower mold, and filtering cloth (26) interposed between the upper molding plate (22) and the lower mold. A process for the manufacture of such segments consists in positioning steel frame (46') in lower mold (21), clamping filtering cloth (26) and rubber strip seal (27) on the lower mold by screwing porous upper molding plate (22) to the lower mold, the upper molding plate (22) and the lower mold constituting a steel form device (20); filling said device (20) with concrete poured through inlet tube (25) under a high pressure; moving device (20) into a steam curing chamber for curing of the concrete; thereafter, removing upper molding plate (22), filtering cloth (26), and a semi-manufactured segment from the lower mold; smoothing the surfaces of the semi-manufactured segment; and immersing it into water for concrete curing. <IMAGE>
Description
Title: MANUFACTURING APPARATUS AND PROCESS FOR A
REINFORCED RING CONCRETE SEGMENT
This invention relates to a manufacturing apparatus and process for a reinforced ring concrete segment, more particularly to a highly efficient manufacturing apparatus and process which can reduce greatly the manufacturing costs and the manual operations involved.
When adopting the so-called "SHIELD METHOD" to form an underground passage, such as subways and underground channels, a shield machine is driven to dig the underground passage. Subsequently, ring concrete segments are assembled together to constitute a ring shield behind the shield machine so as to isolate the space within the ring shield from the surrounding soil.
The ring shield consists of many ring shield units, each of which is normally formed from three to eight steel reinforced ring concrete segments. For example, a ring shield with a length of 1000 m comprises about 3300-8800 pieces of ring concrete segments. The ring concrete segments must have a strength which is sufficient to resist the pressure from the surrounding soil. When one of the segments is too weak to resist the pressure from the surrounding soil, an opening is formed at the same position. Underground water carries soil to flow into the ring shield through the opening, causing probable road collapse. Accordingly, the ring concrete segments have a very high quality requirement.
Referring to Figs. 1A and 1B, a conventional manufacturing apparatus for a reinforced ring concrete segment includes a lower mold (11), a curved upper molding plate (12), a form support (13) and a high frequency oscillator (14). The lower mold (11) and the upper molding plate (12) constitute together a steel form device. The lower mold (11) is fixed on the form support (13). The form support (13) is fixed on the oscillator (14). The lower mold (11) includes a lower molding plate (111), two side molding plates (112), and curved front and rear molding plates (113). The front and rear molding plates (113) are interlocked by means of a locking bolt (15) and are equipped with rollers (1131). The upper molding plate (12) includes a funnel-like concrete inlet device (121).A ring concrete segment is manufactured in the following sequence: 1. positioning a steel frame (46) in the lower mold (11); 2. covering the lower mold (11) with the upper molding plate (12); 3. pouring concrete into the steel form device through the funnel-like concrete inlet device (121); 4. driving the oscillator (14) to oscillate strongly the steel form device so as to distribute uniformly concrete in the steel form device, thereby removing bubbles from the concrete within the lower mold (11); 5. after half an hour, removing the upper molding plate (12) from the lower mold (11); 6. smoothing the semi-manufactured ring concrete segment; 7. putting the semi-manufactured ring concrete segment in a steam curing chamber for about four hours; 8. removing the front and rear molding plates (113) from the semi-manufactured ring concrete segment; and 9. immersing the semi-manufactured segment in water to cure concrete.
To fill uniformly the curved steel form device with concrete, the concrete poured into the steel form device in step 3 has a small water-cement ratio of about 1/0.35 to 1/1.28 and a slump of about 0 to 2 cm in a slump test.
In consideration of safety problems, a rather high precision of the ring concrete segment is demanded.
However, because the upper molding plate (12) is not fastened to the lower mold (11), the steel form device is too weak and is only able to resist a limited pressure from concrete which is poured into the steel form device. Therefore, in order to remove effectively redundant water from the ring concrete segment, the semi-manufactured ring concrete segment needs to be oscillated for an extended time. Lower pressure resisting strength of the steel form device and the long-term oscillation reduce the life time of the steel form device. Accordingly, after manufacturing 100 to 150 pieces of ring concrete segments, it is necessary to replace the steel form device in order to obtain sufficient precision of the segments, thereby resulting in increased manufacturing costs.Furthermore, one must take much time to smooth the surfaces of the ring concrete segment, thus resulting in increased labor costs.
An object of this invention is to provide a highly efficient manufacturing apparatus and process for a reinforced ring concrete segment, which manufacturing apparatus and process can reduce greatly the manufacturing costs and the manual operations involved.
Another object of this invention is to provide a manufacturing apparatus and process for a reinforced ring concrete segment, whereby good-quality products can be obtained.
According to one aspect of this invention, a manufacturing apparatus for a reinforced ring concrete segment includes a steel form device which consists of a lower mold, a porous upper molding plate screwed to the lower mold, and a filtering cloth interposed between the upper molding plate and the lower mold.
According to another aspect of this invention, a manufacturing process for a reinforced ring concrete segment includes the following steps: positioning a steel frame in a lower mold; placing a filtering cloth and an endless sealing rubber strip on the lower mold; screwing a porous upper molding plate to the lower mold so as to clamp the filtering cloth and the sealing rubber strip between the upper molding plate and the lower mold, the upper molding plate and the lower mold constituting a steel form device; pouring concrete into the steel form device through a concrete inlet tube under a high pressure so as to fill the steel form with concrete; moving the steel form device into a steam curing chamber for steam curing of concrete; removing the upper molding plate, the filtering cloth, and a semi-manufactured segment from the lower mold; smoothing the surfaces of the semi-manufactured segment; and immersing the semi-manufactured segment in water for concrete curing.
Other features and advantages of this invention will become apparent in the following detailed description of a preferred embodiment of this invention, with reference to the accompanying drawings, in which:
Figs. 1A and 1B illustrate a conventional manufacturing apparatus for a reinforced ring concrete segment;
Fig. 2 is a front view of a manufacturing apparatus for a reinforced ring concrete segment according to this invention;
Fig. 3 is a side view showing the manufacturing apparatus of this invention;
Fig. 4 is a top view showing the manufacturing apparatus of this invention;
Fig. 5 is a top view showing the lower mold of the manufacturing apparatus of this invention; and
Fig. 6 is a schematic sectional view illustrating how the upper molding plate and the lower mold are interconnected in accordance with this invention.
Referring to Figs. 2 and 3, an apparatus of this invention is used to manufacture a reinforced ring concrete segment and includes a steel form device (20), a high frequency oscillator (30) and a form support (60). The steel form device (20) is supported on the form support (60). The form support (60) is fixed on the oscillator (30).
The steel form device (20) includes a lower molding plate (21), a curved porous upper molding plate (22), two side molding plates (23), and front and rear molding plates (24). The front, rear and side molding plates (24, 23) are fixed on the lower molding plate (21) so as to constitute a lower mold. The front and rear molding plates (24) are interlocked by means of a locking bolt (201) and are equipped with rollers (242) in a known manner.
Referring to Figs. 4, 5 and 6, fastening plates (231, 241) project outward from the upper ends of the side, front and rear molding plates (23, 24) so as to fasten the upper molding plate (22) to the lower mold by means of locking bolts (41). A concrete inlet tube (25) extends through and is retained on the upper molding pate (22) in such a manner that a liquid-tight seal is established therebetween. The upper molding plate (22) has a plurality of drain holes (221). As best shown in Fig. 6, a filtering cloth (26) is clamped between the upper molding plate (22) and the fastening plates (231, 241) of the lower mold. An endless sealing rubber strip (27) is interposed between the upper molding plate (22) and the lower mold so as to establish a liquid-tight seal therebetween.
As best shown in Figs. 2 and 3, the upper molding plate (22) has a curved front side with a front stop plate (28) projecting upward therefrom, a curved rear side with a rear stop plate (28) projecting upward therefrom, a straight left side with a left water collecting member (29) attached thereto, and a straight right side with a right water collecting member (29) attached thereto. The left water collecting member (29) has a left water collecting slot formed therein which extends from the front stop plate (28) to the rear stop plate (28). Similarly, the right water collecting member (29) has a right water collecting slot.
Referring once more to Fig. 2, a ring concrete segment is manufactured in the following sequence: 1. positioning a steel frame (46') in the lower mold of the steel form device (20); 2. placing the filtering cloth (26) and the sealing rubber strip (27) in position on the lower mold of the steel form device (20); 3. screwing the upper molding plate (22) to the lower mold by means of the locking bolts (41); 4. coupling the concrete inlet tube (25) with a concrete feeding tube (50) by means of a high-speed joint (42) so as to pour concrete into the steel form device (20) under a high pressure, redundant water and bubbles moving out of the steel form device (20) through the drain holes (221) of the upper molding plate (22) in such a manner that the filtering cloth (26) prevents cement, sand and gravel from moving into the drain holes (221), in this way, concrete being able to fill uniformly the curved cavity of the steel form device (20), the front and rear stop plates (28) enabling water flowing from the drain- holes (221) to flow into the water collecting slots of the water collecting members (29);; 5. oscillating strongly the steel form device (20) by means of the oscillator (30) so as to reduce the watercement ratio of the concrete within the steel form device (20) and so as to eliminate bubbles in the device (20); 6. moving the steel form device (20) into a steam curing chamber for steam curing of concrete, the steam being able to flow from the concrete within the device (20) through the drain holes (221) so as to solidify the concrete; 7. removing the upper molding plate (22) and the filtering cloth (26) from the lower mold of the steel form device (20); 8. holding the concrete inlet tube (25) and forcing the semi-manufactured ring concrete segment to separate from the same by tipping or striking the segment; 9. smoothing the surfaces of the semi-manufactured segment; and 10. immersing the semi-manufactured segment into water in a pool to cure concrete.
Because the upper molding plate (22) is secured to the lower mold so as to enable concrete to be poured into the steel form device (20) under a very high pressure, the concrete can be distributed uniformly within the device (20) in a less time, as compared to that necessary in the conventional apparatus shown in
Figs. 1A and 1B. Accordingly, the time spent to oscillate and smooth the semi-manufactured segment can be greatly reduced. As a consequence, the quality of the product manufactured by the apparatus of this invention is superior to that manufactured by the prior art apparatus. Furthermore, the steel form device of this invention can resist a higher pressure from concrete than can the prior art. It is tested that one steel form device of this invention can make about 300 pieces of qualified ring concrete segments, which is far more than that made by the prior art apparatus.
Claims (7)
1. A manufacturing apparatus for a reinforced ring concrete segment, including a steel form device and a form support for supporting the steel form device thereon, the steel form device including a lower molding plate, a curved front molding plate fixed on the front portion of the lower molding plate, a curved rear molding plate fixed on the rear portion of the lower molding plate, two side molding plates fixed on two opposite sides of the lower molding plate and interconnecting said front and rear molding plates, and a curved upper molding plate attached to the upper ends of the front, rear and side molding plates so as to define a mold cavity thereamong, characterized in that the upper molding plate has a plurality of drain holes formed therethrough and is screwed to the front, rear and side molding plates, the steel form device further including a concrete inlet tube extending through the upper molding plate in such a manner that a liquidtight seal is established between the concrete inlet tube and the upper molding plate, and a filtering cloth covering the entire inner surface of the upper molding plate, whereby, when concrete is poured into the mold cavity through the concrete inlet tube, water flows out of the steel mold device through the filtering cloth and the drain holes of the upper molding plate.
2. A manufacturing apparatus as claimed in Claim 1, further comprising a high frequency oscillator on which the form support is fixed.
3. A manufacturing apparatus as claimed in Claim 1, wherein the upper molding plate has a front side with a front stop plate projecting upward therefrom, a rear side with a rear stop plate projecting upward therefrom, a left side with a left water collecting slot formed therein, and a right side with a right water collecting slot formed therein, the left and right water collecting slots extending from the front stop plate to the rear stop plate.
4. A manufacturing apparatus as claimed in Claim 1, wherein the filtering cloth is clamped between the upper molding plate and all of the front, rear and side molding plates at the periphery thereof, the steel form device including an endless sealing rubber strip interposed between the upper molding plate and all of the front, rear side molding plates so as to establish a liquid-tight seal therebetween.
5. A manufacturing apparatus substantially as described hereinbefore with reference to figures 2 to 6 of the accompanying drawings.
6. A manufacturing process for a reinforced ring concrete segment, comprising the steps of: (1) providing a lower mold which has a lower molding plate, a front molding plate fixed on the front portion of the lower molding plate, a rear molding plate fixed on the rear portion of the lower molding plate, and two side molding plates fixed on two opposite sides of the lower molding plate and interconnecting said front and rear molding plates; (2) positioning a steel frame in the lower mold; (3) placing a filtering cloth and an endless sealing rubber strip on the upper end portion of the lower mold;; (4) screwing a porous upper molding plate to the upper end portion of the lower mold so as to clamp the filtering cloth and the sealing rubber strip between the upper molding plate and the lower mold, thereby establishing a liquid-tight seal between a periphery of the upper molding plate and the lower mold, the upper molding plate having a plurality of drain holes formed therethrough and being provided with a concrete inlet tube extending therethrough, the concrete inlet tube being retained on the upper molding plate in such a manner that a liquid-tight seal is established therebetween, the upper molding plate and the lower mold together constituting a steel form device; ; (5) pouring concrete into the steel form device through the concrete inlet tube under a high pressure so as to fill the steel form device with concrete, thereby removing bubbles and redundant water from the steel form device through the drai-n holes of the upper molding plate; (6) moving the steel form device into a steam curing chamber for steam curing of concrete; (7) removing the upper molding plate, the filtering cloth, and a semi-manufactured ring concrete segment from the lower mold; (8) smoothing surfaces of the semi-manufactured ring concrete segment; and (9) immersing the semi-manufactured ring concrete segment into water for concrete curing.
7. A manufacturing process as claimed in Claim 6, further comprising after step (6) the step of oscillating the steel form device in such a manner that the steel form device is placed on a high frequency oscillator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9220041A GB2270647A (en) | 1992-09-22 | 1992-09-22 | Apparatus and method for moulding of reinforced concrete ring segments |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9220041A GB2270647A (en) | 1992-09-22 | 1992-09-22 | Apparatus and method for moulding of reinforced concrete ring segments |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9220041D0 GB9220041D0 (en) | 1992-11-04 |
| GB2270647A true GB2270647A (en) | 1994-03-23 |
Family
ID=10722327
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9220041A Withdrawn GB2270647A (en) | 1992-09-22 | 1992-09-22 | Apparatus and method for moulding of reinforced concrete ring segments |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2270647A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0683714A1 (en) * | 1992-11-17 | 1995-11-29 | Ribbon Technology Corporation | Method for manufacturing a reinforced cementitious structural member |
| EP0921107A1 (en) * | 1997-11-24 | 1999-06-09 | Materiaux De Construction International (M.C.I. S.A.) | Mixture for producing glass fibre-reinforced concrete mouldings and process and equipment for producing such mouldings |
| ES2322421A1 (en) * | 2007-04-09 | 2009-06-19 | Carlos Fradera Pellicer | Method for the manufacture of prefabricated panels and plates of armed mortar (Machine-translation by Google Translate, not legally binding) |
| WO2010049544A1 (en) * | 2008-10-28 | 2010-05-06 | Pellicer Carlos F | Method for manufacturing prefabricated reinforced-mortar panels and slabs |
| CN108356966A (en) * | 2018-02-08 | 2018-08-03 | 中铁隧道集团四处有限公司 | The steam-cured construction method of prefabricated case beam integral high-temperature |
| ES2683909R1 (en) * | 2017-03-28 | 2018-10-16 | Corporacion Omegazeta S.L. | Procedure to manufacture a curved panel of prestressed cement mortar, and corresponding curved panel. |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1179405A (en) * | 1966-02-16 | 1970-01-28 | Nat Res Dev | Process for Producing a Concrete Article |
| GB1434734A (en) * | 1972-05-30 | 1976-05-05 | Safeticurb Ltd | Manufacture of concrete products |
| GB2158767A (en) * | 1984-05-17 | 1985-11-20 | Paterson Precast Limited Rober | Production of pressed concrete product |
| GB2229132A (en) * | 1989-02-21 | 1990-09-19 | P G Lawton | Pressing concrete bodies and expressing water therefrom |
-
1992
- 1992-09-22 GB GB9220041A patent/GB2270647A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1179405A (en) * | 1966-02-16 | 1970-01-28 | Nat Res Dev | Process for Producing a Concrete Article |
| GB1434734A (en) * | 1972-05-30 | 1976-05-05 | Safeticurb Ltd | Manufacture of concrete products |
| GB2158767A (en) * | 1984-05-17 | 1985-11-20 | Paterson Precast Limited Rober | Production of pressed concrete product |
| GB2229132A (en) * | 1989-02-21 | 1990-09-19 | P G Lawton | Pressing concrete bodies and expressing water therefrom |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0683714A1 (en) * | 1992-11-17 | 1995-11-29 | Ribbon Technology Corporation | Method for manufacturing a reinforced cementitious structural member |
| EP0683714A4 (en) * | 1992-11-17 | 1997-06-04 | Ribbon Technology Corp | Method for manufacturing a reinforced cementitious structural member. |
| EP0921107A1 (en) * | 1997-11-24 | 1999-06-09 | Materiaux De Construction International (M.C.I. S.A.) | Mixture for producing glass fibre-reinforced concrete mouldings and process and equipment for producing such mouldings |
| ES2322421A1 (en) * | 2007-04-09 | 2009-06-19 | Carlos Fradera Pellicer | Method for the manufacture of prefabricated panels and plates of armed mortar (Machine-translation by Google Translate, not legally binding) |
| WO2010049544A1 (en) * | 2008-10-28 | 2010-05-06 | Pellicer Carlos F | Method for manufacturing prefabricated reinforced-mortar panels and slabs |
| ES2683909R1 (en) * | 2017-03-28 | 2018-10-16 | Corporacion Omegazeta S.L. | Procedure to manufacture a curved panel of prestressed cement mortar, and corresponding curved panel. |
| CN108356966A (en) * | 2018-02-08 | 2018-08-03 | 中铁隧道集团四处有限公司 | The steam-cured construction method of prefabricated case beam integral high-temperature |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9220041D0 (en) | 1992-11-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |