CN111618974A - Reinforced concrete segment prefabrication molding construction method for shield tunneling construction - Google Patents

Abstract

The invention discloses a shield segment prefabricating method, which comprises the following steps: step 1, manufacturing, cleaning and assembling a segment mold; step 2, manufacturing a reinforcement cage; step 3, mounting the circular steel edge water stop ring and the two water stop caps on the embedded pipe; step 4, fixing the assembled embedded pipe on a reinforcement cage, and placing the reinforcement cage in a mold; step 5, mixing cement, water, sand, stones, a water reducing agent and fly ash to prepare concrete; step 6, spreading concrete in the mould, vibrating the concrete and plastering; step 7, performing steam curing on the concrete pipe sheet; step 8, demoulding the concrete segment; and 9, performing water curing on the concrete pipe. The shield segment prefabricating method provided by the invention can effectively reduce the water leakage rate in the secondary grouting process.

Description

Reinforced concrete segment prefabrication molding construction method for shield tunneling construction

Technical Field

The invention relates to the technical field of building construction, in particular to a reinforced concrete segment prefabrication molding construction method for shield tunneling construction.

Background

The urbanization speed of China is continuously accelerated, traffic jam is a difficult problem before the China is in the future, and subways are generated by increasing the traffic modes of people under the condition of not occupying land resources. At present, the urban underground tunnel is mainly tunneled by a shield machine, and the method is safe and reliable, low in cost and convenient in shield segment installation. The shield segment is a main assembly component for shield construction, is an innermost barrier of a tunnel and plays a role in resisting soil pressure, underground water pressure and some special loads, and the quality of the shield segment is related to the overall quality and safety of the tunnel.

For example, the invention with Chinese patent application number 201810668351.8 discloses a method for manufacturing a prefabricated reinforced concrete segment for a shield, which comprises the production steps of reinforcement cage processing, concrete pouring, vibration, steam curing, pool curing and segment detection, and the prefabricated reinforced concrete segment with good performance is produced by optimally designing the process parameters in the steps.

The prior art has at least the following problems:

1. the shield structure tunnelling takes place in rich water sand bed, and the moisture content is higher, runs through to the section of jurisdiction that needs secondary slip casting along with the electric drill, further disturbs this regional geology, very easily aggravates the seepage rate, and traditional slip casting hole shutoff measure construction finishes the back, and the slip casting hole is terminal still not effectively to reduce the seepage rate, and hidden danger is great, and follow-up needs carry out many times remedial measure to this position, extravagant a large amount of funds.

2. The shield segment concrete mixing proportion can not meet the characteristics of high strength, high impermeability, good durability and good steam curing adaptability.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide the reinforced concrete segment prefabrication and forming construction method for shield tunneling construction, which can effectively reduce the water leakage rate in the secondary grouting process, and the prepared concrete segment has high impermeability, good durability and good steam-curing adaptability.

The reinforced concrete segment prefabrication molding construction method for shield tunneling construction comprises the following steps:

step 1, manufacturing, assembling and cleaning a tube sheet die;

step 2, manufacturing a reinforcement cage;

step 3, mounting the circular steel edge water stop ring and the two water stop caps on the embedded pipe;

step 4, fixing the assembled embedded pipe on a reinforcement cage, and placing the reinforcement cage in a segment mould;

step 5, mixing cement, water, sand, stones, a water reducing agent and fly ash to prepare concrete;

step 6, spreading concrete in the segment mould, vibrating the concrete and plastering;

step 7, performing steam curing on the concrete pipe sheet;

step 8, demoulding the concrete segment;

and 9, performing water curing on the concrete pipe.

Further, the manufacturing, assembling and cleaning tube sheet die in the step 1 comprises:

step 1.1, manufacturing a bottom plate, a side plate and an upper cover of a segment mould;

step 1.2, fixing a bottom plate and a side plate of the segment mould by using fixing bolts;

step 1.3, cleaning attachments and rust on the surface of the pipe sheet die by using dry cleaning cloth according to the sequence of firstly cleaning the inside, secondly cleaning the outside, firstly cleaning the middle and secondly cleaning the periphery;

step 1.4, cleaning a hand hole seat of the tube sheet die by using a laser cleaning machine;

and step 1.5, blowing off attachments inside and outside the segment mould by using a compressed air blowing gun.

Further, the step 2 of manufacturing the reinforcement cage comprises:

step 2.1, manufacturing a steel reinforcement cage rack component according to the structural size of the shield segment;

step 2.2, welding a steel reinforcement cage rack component;

step 2.3, positioning and marking the main reinforcement positions of the segment reinforcement cage on a cross beam of the reinforcement cage rack;

step 2.4, cutting a groove with the width and the depth larger than the diameter of the main reinforcement of the reinforcement cage at the position of a beam measurement mark of the reinforcement cage rack by using a handheld cutter;

step 2.5, polishing the grooving part of the beam and the welding joint of the reinforcement cage rack by using a handheld cutter;

step 2.6, placing the prefabricated segment steel reinforcement cage main reinforcement into a groove on a rack beam, then installing a segment steel reinforcement cage stirrup, welding the steel reinforcement cage main reinforcement, wherein the gap between the steel reinforcement cage main reinforcement and the stirrup is smaller than 10mm, and installing a steel reinforcement cage hook reinforcement;

and 2.7, after the reinforcement cage is manufactured on the reinforcement cage rack, using a crane to lift the reinforcement cage out of the reinforcement cage rack and placing the reinforcement cage in a storage place.

Further, step 3 the installation of the circular steel-edged water stop ring and the two water stop caps on the embedded pipe comprises:

step 3.1, manufacturing a circular steel edge water stop ring, wherein the center of the circular steel edge water stop ring is made of rubber, the size of the rubber is equal to the inner diameter of an electric drill, and the rest parts of the circular steel edge water stop ring are galvanized steel plates;

step 3.2, mounting a circular steel edge water stop ring at the central position of the embedded pipe;

and 3.3, respectively sleeving the two water stopping caps at two ends of the embedded pipe, and sleeving the waterproof sealing washer on the water stopping cap corresponding to the end part of the embedded pipe after the two water stopping caps are installed.

Further, the step 4 of placing the reinforcement cage in the segment mold comprises aligning a pre-embedded pipe on the reinforcement cage with a gasket which is placed in advance at the hole position of the hand hole seat and fixing the pre-embedded pipe with a spring thimble.

Further, in the step 5, cement, water, sand, gravel, a water reducing agent and fly ash are mixed to prepare concrete, wherein the cement comprises 370 parts by weight, 139 parts by weight, 670 parts by weight, 1244 parts by weight, 10 parts by weight of the water reducing agent and 80 parts by weight of the fly ash; wherein the cement is P.O42.5 cement; the fineness modulus of the sand is 2.8, the mud content is 1%, the mud block content is 0.2%, and the chloride ion content is 0.003%; the mud content of the stones is less than or equal to 1 percent, the mud content is less than or equal to 0.5 percent, and 5-10mm continuous particle size fraction and 10-25mm single particle size fraction are selected for compounding according to the weight portion of 30: 70; the water reducing agent is SP401 type naphthalene water reducing agent.

Further, step 6, spreading concrete in the segment mold, and vibrating and plastering the concrete includes:

step 6.1, paving the concrete at two ends of the pipe piece mold, paving the middle part of the pipe piece mold, and layering the paving process;

step 6.2, when the inner surface of the pipe sheet mould is covered with concrete to be paved, adopting an attached vibrator to vibrate for 3-5 minutes;

and 6.3, after the vibration is finished, firstly performing rough plastering on the surface of the concrete to smooth the surface of the concrete, then performing intermediate plastering, finishing by using a lime spoon after the surface of the concrete receives water, and finally performing fine plastering by using a long spoon.

Further, the step 7 of steam curing the concrete segment includes:

step 7.1, before steam curing, covering a plastic film on the concrete pipe sheet, and standing for 1-2 hours;

step 7.2, heating and maintaining the concrete segment, wherein the heating time is controlled to be 2-3 hours, the heating speed is not more than 15 ℃/hour, and the highest temperature is not more than 60 ℃;

7.3, maintaining the concrete segment at constant temperature, wherein the constant temperature time is controlled to be 1.5 hours, and the highest temperature is not more than 65 ℃;

and 7.4, finally, cooling and maintaining the concrete segment, wherein the cooling speed is not more than 10 ℃/hour.

Further, the step 8 of demolding the concrete segment includes:

8.1, loosening the fixing bolts, opening the side die plate of the segment die, opening the end plate of the segment die, and connecting the lifting appliance with the concrete segment for vibration demoulding;

and 8.2, hoisting the concrete segment to a segment turnover machine for 90-degree turnover, and hoisting the side-erected concrete segment away.

Further, the step 9 of performing water curing on the concrete pipe piece comprises:

step 9.1, monitoring the surface temperature of the concrete pipe piece and the water temperature of the water curing pool to ensure that the difference between the surface temperature of the concrete pipe piece and the water temperature of the water curing pool is less than or equal to 20 ℃ before the concrete pipe piece is moved into the water curing pool;

step 9.2, moving the demolded concrete pipe piece to a water curing pool, and carrying out water curing for at least 7 days;

and 9.3, hanging the concrete pipe sheet out of the curing pool, and performing natural curing until the strength curing is finished for 28 days.

Compared with the prior art, the shield segment prefabricating method has the following advantages:

1. by adopting the shield segment prefabricating method, the water stop cap sleeved at the bottom end of the embedded pipe of the prepared segment is a first waterproof line after grouting is finished, the water stop cap is embedded in the segment in advance, a later plugging procedure is reduced, the circular steel edge rubber water stop ring arranged in the middle of the embedded pipe is a second waterproof line after grouting, a leakage water path is further prolonged, and therefore the penetration resistance is greatly increased, the central part of the circular steel edge rubber water stop ring is a rubber part, and an electric drill can penetrate through the embedded pipe and the concrete segment conveniently.

2. By adopting the shield segment prefabricating method, the prepared concrete segment is high in strength, high in impermeability, good in durability and good in steam curing adaptability.

Drawings

Fig. 1 is a schematic structural view of the assembled pre-buried pipe of the present invention.

Shown in the figure: 1-pre-burying a pipe; 2-water stopping cap; 3-waterproof sealing gasket; 4-round steel edge water stop ring.

Detailed Description

The concrete embodiment of the reinforced concrete segment prefabricating and forming construction method for shield tunneling construction according to the present application will now be described in detail with reference to the attached drawing 1 of the specification.

The reinforced concrete segment prefabrication molding construction method for shield tunneling construction comprises the following steps:

step 1, manufacturing, assembling and cleaning a tube sheet die;

step 2, manufacturing a reinforcement cage;

step 3, mounting the circular steel edge water stop ring 4 and the two water stop caps 2 on the embedded pipe 1;

step 4, fixing the assembled embedded pipe 1 on a reinforcement cage, and placing the reinforcement cage in a segment mould;

step 5, mixing cement, water, sand, stones, a water reducing agent and fly ash to prepare concrete;

step 6, spreading concrete in the segment mould, vibrating the concrete and plastering;

step 7, performing steam curing on the concrete pipe sheet;

step 8, demoulding the concrete segment;

and 9, performing water curing on the concrete pipe.

Further, the manufacturing, assembling and cleaning tube sheet die in the step 1 comprises:

step 1.1, manufacturing a bottom plate, a side plate and an upper cover of a segment mould;

step 1.2, fixing a bottom plate and a side plate of the segment mould by using fixing bolts;

step 1.3, cleaning attachments and rust on the surface of the pipe sheet die by using dry cleaning cloth according to the sequence of firstly cleaning the inside, secondly cleaning the outside, firstly cleaning the middle and secondly cleaning the periphery;

step 1.4, cleaning a hand hole seat of the tube sheet die by using a laser cleaning machine;

and step 1.5, blowing off attachments inside and outside the segment mould by using a compressed air blowing gun.

Further, the step 2 of manufacturing the reinforcement cage comprises:

step 2.1, manufacturing a steel reinforcement cage rack component according to the structural size of the shield segment;

step 2.2, welding a steel reinforcement cage rack component;

step 2.3, positioning and marking the main reinforcement positions of the segment reinforcement cage on a cross beam of the reinforcement cage rack;

step 2.4, cutting a groove with the width and the depth larger than the diameter of the main reinforcement of the reinforcement cage at the position of a beam measurement mark of the reinforcement cage rack by using a handheld cutter;

step 2.5, polishing the grooving part of the beam and the welding joint of the reinforcement cage rack by using a handheld cutter;

step 2.6, placing the prefabricated segment steel reinforcement cage main reinforcement into a groove on a rack beam, then installing a segment steel reinforcement cage stirrup, welding the steel reinforcement cage main reinforcement, wherein the gap between the steel reinforcement cage main reinforcement and the stirrup is smaller than 10mm, and installing a steel reinforcement cage hook reinforcement;

and 2.7, after the reinforcement cage is manufactured on the reinforcement cage rack, using a crane to lift the reinforcement cage out of the reinforcement cage rack and placing the reinforcement cage in a storage place.

Further, the step 3 of installing the circular steel-edged water stop ring 4 and the two water stop caps 2 on the embedded pipe 1 comprises:

step 3.1, manufacturing a circular steel edge water stop ring 4, wherein rubber is adopted in the center of the circular steel edge water stop ring 4, the size of the rubber is equal to the inner diameter of an electric drill, and the rest parts of the circular steel edge water stop ring 4 are galvanized steel plates;

step 3.2, installing a circular steel edge water stop ring 4 at the central position of the embedded pipe 1;

and 3.3, respectively sleeving the two water stopping caps 2 at two ends of the embedded pipe 1, and sleeving the waterproof sealing washer 3 on the water stopping cap 2 corresponding to the end part of the embedded pipe 1 after the two water stopping caps 2 are installed.

Further, the step 4 of placing the reinforcement cage in the segment mold comprises aligning a pre-embedded pipe on the reinforcement cage with a gasket which is placed in advance at the hole position of the hand hole seat and fixing the pre-embedded pipe with a spring thimble.

Further, in the step 5, cement, water, sand, gravel, a water reducing agent and fly ash are mixed to prepare concrete, wherein the cement comprises 370 parts by weight, 139 parts by weight, 670 parts by weight, 1244 parts by weight, 10 parts by weight of the water reducing agent and 80 parts by weight of the fly ash; wherein the cement is P.O42.5 cement; the fineness modulus of the sand is 2.8, the mud content is 1%, the mud block content is 0.2%, and the chloride ion content is 0.003%; the mud content of the stones is less than or equal to 1 percent, the mud content is less than or equal to 0.5 percent, and 5-10mm continuous particle size fraction and 10-25mm single particle size fraction are selected for compounding according to the weight portion of 30: 70; the water reducing agent is SP401 type naphthalene water reducing agent.

Further, step 6, spreading concrete in the segment mold, and vibrating and plastering the concrete includes:

step 6.1, paving the concrete at two ends of the pipe piece mold, paving the middle part of the pipe piece mold, and layering the paving process;

step 6.2, when the inner surface of the pipe sheet mould is covered with concrete to be paved, adopting an attached vibrator to vibrate for 3-5 minutes;

and 6.3, after the vibration is finished, firstly performing rough plastering on the surface of the concrete to smooth the surface of the concrete, then performing intermediate plastering, finishing by using a lime spoon after the surface of the concrete receives water, and finally performing fine plastering by using a long spoon.

Further, the step 7 of steam curing the concrete segment includes:

step 7.1, before steam curing, covering a plastic film on the concrete pipe sheet, and standing for 1-2 hours;

step 7.2, heating and maintaining the concrete segment, wherein the heating time is controlled to be 2-3 hours, the heating speed is not more than 15 ℃/hour, and the highest temperature is not more than 60 ℃;

7.3, maintaining the concrete segment at constant temperature, wherein the constant temperature time is controlled to be 1.5 hours, and the highest temperature is not more than 65 ℃;

and 7.4, finally, cooling and maintaining the concrete segment, wherein the cooling speed is not more than 10 ℃/hour.

Further, the step 8 of demolding the concrete segment includes:

8.1, loosening the fixing bolts, opening the side die plate of the segment die, opening the end plate of the segment die, and connecting the lifting appliance with the concrete segment for vibration demoulding;

and 8.2, hoisting the concrete segment to a segment turnover machine for 90-degree turnover, and hoisting the side-erected concrete segment away.

Further, the step 9 of performing water curing on the concrete pipe piece comprises:

step 9.1, monitoring the surface temperature of the concrete pipe piece and the water temperature of the water curing pool to ensure that the difference between the surface temperature of the concrete pipe piece and the water temperature of the water curing pool is less than or equal to 20 ℃ before the concrete pipe piece is moved into the water curing pool;

step 9.2, moving the demolded concrete pipe piece to a water curing pool, and carrying out water curing for at least 7 days;

and 9.3, hanging the concrete pipe sheet out of the curing pool, and performing natural curing until the strength curing is finished for 28 days.

The present invention is not limited to the above-described embodiments, and any variations, modifications, and alterations that may occur to one skilled in the art without departing from the spirit of the invention are intended to be within the scope of the invention.

Claims (10)

1. A reinforced concrete segment prefabrication molding construction method for shield tunneling construction comprises the following steps:

step 1, manufacturing, assembling and cleaning a tube sheet die;

step 2, manufacturing a reinforcement cage;

step 3, mounting the circular steel edge water stop ring and the two water stop caps on the embedded pipe;

step 4, fixing the assembled embedded pipe on a reinforcement cage, and placing the reinforcement cage in a segment mould;

step 5, mixing cement, water, sand, stones, a water reducing agent and fly ash to prepare concrete;

step 6, spreading concrete in the segment mould, vibrating the concrete and plastering;

step 7, performing steam curing on the concrete pipe sheet;

step 8, demoulding the concrete segment;

and 9, performing water curing on the concrete pipe.

2. The reinforced concrete segment prefabrication and molding construction method as claimed in claim 1, wherein the tube sheet manufacturing, assembling and cleaning mould in the step 1 comprises:

step 1.1, manufacturing a bottom plate, a side plate and an upper cover of a segment mould;

step 1.2, fixing a bottom plate and a side plate of the segment mould by using fixing bolts;

step 1.3, cleaning attachments and rust on the surface of the pipe sheet die by using dry cleaning cloth according to the sequence of firstly cleaning the inside, secondly cleaning the outside, firstly cleaning the middle and secondly cleaning the periphery;

step 1.4, cleaning a hand hole seat of the tube sheet die by using a laser cleaning machine;

and step 1.5, blowing off attachments inside and outside the segment mould by using a compressed air blowing gun.

3. The reinforced concrete segment prefabrication and forming construction method as claimed in claim 1, wherein the step 2 of manufacturing a reinforcement cage comprises the following steps:

step 2.1, manufacturing a steel reinforcement cage rack component according to the structural size of the shield segment;

step 2.2, welding a steel reinforcement cage rack component;

step 2.3, positioning and marking the main reinforcement positions of the segment reinforcement cage on a cross beam of the reinforcement cage rack;

step 2.4, cutting a groove with the width and the depth larger than the diameter of the main reinforcement of the reinforcement cage at the position of a beam measurement mark of the reinforcement cage rack by using a handheld cutter;

step 2.5, polishing the grooving part of the beam and the welding joint of the reinforcement cage rack by using a handheld cutter;

step 2.6, placing the prefabricated segment steel reinforcement cage main reinforcement into a groove on a rack beam, then installing a segment steel reinforcement cage stirrup, welding the steel reinforcement cage main reinforcement, wherein the gap between the steel reinforcement cage main reinforcement and the stirrup is smaller than 10mm, and installing a steel reinforcement cage hook reinforcement;

and 2.7, after the reinforcement cage is manufactured on the reinforcement cage rack, using a crane to lift the reinforcement cage out of the reinforcement cage rack and placing the reinforcement cage in a storage place.

4. The reinforced concrete segment prefabrication and forming construction method as claimed in claim 1, wherein the step 3 of installing the circular steel-edged water stop ring and the two water stop caps on the embedded pipe comprises the following steps:

step 3.1, manufacturing a circular steel edge water stop ring, wherein the center of the circular steel edge water stop ring is made of rubber, the size of the rubber is equal to the inner diameter of an electric drill, and the rest parts of the circular steel edge water stop ring are galvanized steel plates;

step 3.2, mounting a circular steel edge water stop ring at the central position of the embedded pipe;

and 3.3, respectively sleeving the two water stopping caps at two ends of the embedded pipe, and sleeving the waterproof sealing washer on the water stopping cap corresponding to the end part of the embedded pipe after the two water stopping caps are installed.

5. The reinforced concrete segment prefabrication forming construction method of claim 1, wherein the step 4 of placing the reinforcement cage in the segment mold comprises aligning an embedded pipe on the reinforcement cage with a gasket which is placed in advance at a hand hole seat hole position, and fixing the embedded pipe with a spring ejector pin.

6. The reinforced concrete segment prefabrication and molding construction method according to claim 1, wherein in the step 5, cement, water, sand, gravel, a water reducing agent and fly ash are mixed to prepare the concrete, and the cement, the water, the sand and the gravel are 370 parts by weight, the water and the fly ash are 139 parts by weight, 670 parts by weight, 1244 parts by weight, 10 parts by weight of the water reducing agent and 80 parts by weight; wherein the cement is P.O42.5 cement; the fineness modulus of the sand is 2.8, the mud content is 1%, the mud block content is 0.2%, and the chloride ion content is 0.003%; the mud content of the stones is less than or equal to 1 percent, the mud content is less than or equal to 0.5 percent, and 5-10mm continuous particle size fraction and 10-25mm single particle size fraction are selected for compounding according to the weight portion of 30: 70; the water reducing agent is SP401 type naphthalene water reducing agent.

7. The reinforced concrete segment prefabrication and forming construction method as claimed in claim 1, wherein the step 6 of spreading concrete into the segment mould, and vibrating and plastering the concrete comprises the following steps:

step 6.1, paving the concrete at two ends of the pipe piece mold, paving the middle part of the pipe piece mold, and layering the paving process;

step 6.2, when the inner surface of the pipe sheet mould is covered with concrete to be paved, adopting an attached vibrator to vibrate for 3-5 minutes;

and 6.3, after the vibration is finished, firstly performing rough plastering on the surface of the concrete to smooth the surface of the concrete, then performing intermediate plastering, finishing by using a lime spoon after the surface of the concrete receives water, and finally performing fine plastering by using a long spoon.

8. The reinforced concrete segment prefabrication and molding construction method as claimed in claim 1, wherein the step 7 of steam curing the concrete segment comprises the following steps:

step 7.1, before steam curing, covering a plastic film on the concrete pipe sheet, and standing for 1-2 hours;

step 7.2, heating and maintaining the concrete segment, wherein the heating time is controlled to be 2-3 hours, the heating speed is not more than 15 ℃/hour, and the highest temperature is not more than 60 ℃;

7.3, maintaining the concrete segment at constant temperature, wherein the constant temperature time is controlled to be 1.5 hours, and the highest temperature is not more than 65 ℃;

and 7.4, finally, cooling and maintaining the concrete segment, wherein the cooling speed is not more than 10 ℃/hour.

9. The reinforced concrete segment prefabrication and forming construction method as claimed in claim 1, wherein the step 8 of demoulding the concrete segment comprises the following steps:

8.1, loosening the fixing bolts, opening the side die plate of the segment die, opening the end plate of the segment die, and connecting the lifting appliance with the concrete segment for vibration demoulding;

and 8.2, hoisting the concrete segment to a segment turnover machine for 90-degree turnover, and hoisting the side-erected concrete segment away.

10. The reinforced concrete segment prefabrication and forming construction method as claimed in claim 1, wherein the step 9 of performing water curing on the concrete segment comprises the following steps:

step 9.1, monitoring the surface temperature of the concrete pipe piece and the water temperature of the water curing pool to ensure that the difference between the surface temperature of the concrete pipe piece and the water temperature of the water curing pool is less than or equal to 20 ℃ before the concrete pipe piece is moved into the water curing pool;

step 9.2, moving the demolded concrete pipe piece to a water curing pool, and carrying out water curing for at least 7 days;

and 9.3, hanging the concrete pipe sheet out of the curing pool, and performing natural curing until the strength curing is finished for 28 days.

Images