CN111361003A - High-performance steam-curing-free maintenance shield segment - Google Patents
High-performance steam-curing-free maintenance shield segment Download PDFInfo
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- CN111361003A CN111361003A CN202010228246.XA CN202010228246A CN111361003A CN 111361003 A CN111361003 A CN 111361003A CN 202010228246 A CN202010228246 A CN 202010228246A CN 111361003 A CN111361003 A CN 111361003A
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- 238000012423 maintenance Methods 0.000 title claims abstract description 15
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 42
- 239000010959 steel Substances 0.000 claims abstract description 42
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 31
- 238000000034 method Methods 0.000 claims abstract description 27
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 16
- 230000008569 process Effects 0.000 claims abstract description 15
- 230000002787 reinforcement Effects 0.000 claims abstract description 13
- 238000010276 construction Methods 0.000 claims abstract description 12
- 238000005507 spraying Methods 0.000 claims abstract description 10
- 238000003466 welding Methods 0.000 claims description 12
- 238000004519 manufacturing process Methods 0.000 claims description 9
- 239000011241 protective layer Substances 0.000 claims description 9
- 238000001514 detection method Methods 0.000 claims description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- 238000007689 inspection Methods 0.000 claims description 5
- 230000009471 action Effects 0.000 claims description 3
- 235000014121 butter Nutrition 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 238000012790 confirmation Methods 0.000 claims description 3
- 238000013461 design Methods 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 238000005461 lubrication Methods 0.000 claims description 3
- 235000013372 meat Nutrition 0.000 claims description 3
- 230000007246 mechanism Effects 0.000 claims description 3
- 239000003595 mist Substances 0.000 claims description 3
- 239000004570 mortar (masonry) Substances 0.000 claims description 3
- 230000035515 penetration Effects 0.000 claims description 3
- 238000005498 polishing Methods 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 238000007790 scraping Methods 0.000 claims description 3
- 239000002893 slag Substances 0.000 claims description 3
- 238000012360 testing method Methods 0.000 claims description 3
- 230000003245 working effect Effects 0.000 claims description 3
- 238000007599 discharging Methods 0.000 claims description 2
- 239000004568 cement Substances 0.000 abstract description 11
- 239000002253 acid Substances 0.000 abstract description 8
- 239000010881 fly ash Substances 0.000 abstract description 7
- 230000036571 hydration Effects 0.000 abstract description 6
- 238000006703 hydration reaction Methods 0.000 abstract description 6
- 239000003638 chemical reducing agent Substances 0.000 abstract description 4
- 229910052500 inorganic mineral Inorganic materials 0.000 abstract description 3
- 239000011707 mineral Substances 0.000 abstract description 3
- 239000000843 powder Substances 0.000 abstract description 3
- 238000003756 stirring Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000010410 layer Substances 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 238000009415 formwork Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000007306 turnover Effects 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
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- 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
- B28B23/00—Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objects
- B28B23/02—Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objects wherein the elements are reinforcing members
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- 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
- B28B13/00—Feeding the unshaped material to moulds or apparatus for producing shaped articles; Discharging shaped articles from such moulds or apparatus
- B28B13/02—Feeding the unshaped material to moulds or apparatus for producing shaped 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
- B28B13/00—Feeding the unshaped material to moulds or apparatus for producing shaped articles; Discharging shaped articles from such moulds or apparatus
- B28B13/04—Discharging the shaped articles
- B28B13/06—Removing the shaped articles from moulds
-
- 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
- B28B7/0002—Auxiliary parts or elements of the mould
-
- 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
- B28B7/0002—Auxiliary parts or elements of the mould
- B28B7/0014—Fastening means for mould parts, e.g. for attaching mould walls on mould tables; Mould clamps
-
- 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
- B28B7/38—Treating surfaces of moulds, cores, or mandrels to prevent sticking
- B28B7/384—Treating agents
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
- E21D11/04—Lining with building materials
- E21D11/08—Lining with building materials with preformed concrete slabs
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
- E21D11/04—Lining with building materials
- E21D11/08—Lining with building materials with preformed concrete slabs
- E21D11/086—Methods of making concrete lining segments
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- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
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Abstract
The invention discloses a high-performance steam-curing-free maintenance shield segment, which is characterized in that the construction process comprises the steps of forming a mold → spraying a release agent → installing a steel reinforcement cage → pouring concrete → collecting water on an outer cambered surface → demoulding the segment → inspecting a finished product, and is characterized in that: comprises the following six steps. The steam curing-free shield segment concrete can be prepared by adopting the polycarboxylic acid Shanghai Sanrui VIVIID-500A early strength polycarboxylic acid water reducing agent, the initial slump of the concrete is 40mm, the concrete finishing and plastering time is 75min, the 12h strength meets the requirement of stripping, the surface bubbles are less, the cement consumption is reduced to the maximum extent under the condition of meeting the requirements of specification and strength, a large amount of admixture (mainly fly ash and mineral powder) is used, the hydration heat of cement in the early stage is reduced, the crack resistance and the volume stability of the concrete are improved, and the cost of the concrete is effectively reduced.
Description
Technical Field
The invention relates to the technical field of duct piece production and processing, in particular to a high-performance steam-curing-free maintenance shield duct piece.
Background
In order to relieve the urgent need of urban development, China's river-crossing sea-crossing tunnels and urban rail transit are under large-scale construction, at present, shield methods are mostly adopted for underground tunnel construction to replace the original backward labor-intensive construction methods such as open grooving or shallow underground excavation, and the segment performance of the segment, which is the most important and key structural member in the shield tunnel, has decisive influence on the quality and service life of the second project of the shield tunnel.
At present, most of concrete pipe pieces in China are subjected to steam curing to heat concrete by utilizing the heat and humidity effect of steam, the early strength of the concrete is improved by accelerating the hardening process of the concrete, the concrete of the pipe pieces rapidly reaches the lifting and demolding strength to accelerate the turnover of a mold and improve the production efficiency of the pipe pieces, but the steam curing can also generate certain negative effects on the concrete on the premise of improving the early hardening speed of the concrete.
Disclosure of Invention
The invention aims to provide a high-performance steam curing-free shield segment to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
the high-performance steam-curing-free maintenance shield segment has the construction flow of assembling a mould → spraying a release agent → installing a steel reinforcement cage → pouring concrete → collecting water from an outer arc surface → demoulding the segment → inspecting finished products, and is characterized in that: the method comprises the following six steps:
the method comprises the following steps: the module assembling: before the die is assembled, checking all positions of the die, unfolding and pulling out all bolts according to the sequence of closing an end template firstly and closing a side die secondly when the side die is closed, installing fixing bolts of a bottom die and the side die, screwing the fixing bolts by hands firstly, then screwing the fixing bolts from the middle to the two ends in sequence by using a special tool, and adding a release agent into the die after the assembly is finished;
step two: and (3) installing the reinforcement cage: the steel reinforcement framework is welded and molded, the phenomena of meat biting, false welding and slag inclusion cannot occur to welding seams, the length and the height of the welding seams must meet the design requirements, the number of the brackets of the concrete protective layer of the steel reinforcement framework, the height of the protective layer, the number of the installed embedded parts and the attaching degree of the embedded parts and the mold are checked, and the concrete protective layer is installed into the mold after the error is confirmed;
step three: pouring the concrete: the method comprises the following steps of pouring newly-prepared concrete into a duct piece mould by adopting pneumatic integral vibration, reducing the content of gas in the concrete to the maximum extent, wherein when the temperature is lower than 25 ℃, the interval time of discharging the concrete from a stirrer and pouring the concrete into the mould after transportation is not longer than 3 hours, and when the temperature is higher than 25 ℃, the interval time is not longer than 2.5 hours;
step four: the outer arc surface receives water: after concrete pouring, a pressing plate can be removed at intervals according to the air temperature, the water collecting process of the outer arc surface of the duct piece is carried out, the outer arc surface collects water, redundant concrete is scraped by a scraping plate, the arc surface of the duct piece and the outer arc of a steel mould are kept smooth and flat, a pull ruler is used for leveling and compacting, iron plates are used for oil polishing, and then secondary water collection of the outer arc surface of the duct piece is carried out at intervals according to the air temperature;
step five: demolding of the duct piece: a horizontal lifting appliance is adopted for demoulding the shield segment, after the strength of the segment is more than 20MPa, a side plate needs to be firstly disassembled in the demoulding process (namely, a vacuum sucker is 15 MPa), and then an end mould needs to be disassembled, so that the damage phenomenon during the mould disassembling of the segment can be avoided, and the whole mould disassembling process cannot be forcibly disassembled;
step six: and (3) inspecting the finished product: the single-piece duct piece needs to use a vernier caliper to measure the precision, three points are respectively measured on the width of the inner cambered surface and the width of the outer cambered surface, the allowable error is 0.5mm, three points are measured on the thickness, the allowable error is plus 3 to minus 1mm, the chord arc length is plus or minus 1.5mm, the duct piece leakage detection test is qualified under the action of the water pressure of 0.8MPa of leakage detection pressure and the constant pressure for 6 hours, and the penetration depth is less than 5 cm.
Further, the steel mould is cleaned thoroughly during assembly, concrete residues are completely removed, the surface of the steel mould contacting with concrete is cleaned by compressed air, the steel mould is not required to be knocked by a hammer and chiseled by a chisel, the steel mould is removed along the surface of the steel mould, the surface of the steel mould is strictly prevented from being damaged, and the width of the steel mould is measured by an inside micrometer.
Furthermore, before the release agent is sprayed, whether residual concrete exists on the inner surface of the mold needs to be checked, after the confirmation, a water-soluble release agent is selected for spraying, and when the release agent is sprayed, a mist sprayer is used for spraying, and then the mop is used for uniformly coating.
Furthermore, the single steel bar sheet and the framework in the second step are formed by adopting a low-temperature welding process, and when the bent core rod is assembled, fastening of a tightening device of the bent core rod is ensured if necessary, so that the risk that the bent core rod falls off when pouring vibration is carried out, and mortar is poured into the bolt hole to cause silting and the like is avoided.
Further, after the maintenance of the duct piece is completed, the type, the mark, the model, the production serial number, the production date and the inspection state of the duct piece are marked on the side surface of the duct piece and the upper right corner of the inner arc surface, and the duct piece is placed on 3 hard square timbers of 0.1m × 0.1.1 m after the marking is completed and transported to a construction site for assembly.
Furthermore, the lubrication of each clamping position, each bolt connecting point and each running position of the steel die are detected at regular time, and the bolts, the positioning mechanisms and the bent bolts are fastened by injecting butter periodically, otherwise, the opening and closing of the die are easily caused, so that the working effect is reduced, and the application life of the die is shortened.
Compared with the prior art, the invention has the beneficial effects that: according to the preparation method of the high-performance steam curing-free shield segment, the concrete of the steam curing-free segment can be prepared by adopting the polycarboxylic acid Shanghai Sanrui VIVIID-500A early-strength polycarboxylic acid water reducing agent, the initial slump of the concrete is 40mm, the concrete finishing time is 75min, the 12h strength meets the requirement of formwork removal, fewer surface bubbles are generated, the use of a large amount of admixture (mainly fly ash and mineral powder) for cement is reduced to the maximum extent under the condition that the requirements of specification and strength are met, the hydration heat of the cement in the early stage of hydration is reduced, the crack resistance and the volume stability of the concrete are improved, and the cost of the concrete is effectively reduced.
Drawings
FIG. 1 is a schematic flow diagram of a high performance steam curing-free shield segment of the present invention;
FIG. 2 is a segment accuracy requirement diagram of a high performance steam curing-free shield segment of the present invention;
FIG. 3 is a concrete main component proportion diagram of the high-performance steam-curing-free shield segment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "both ends", "one end", "the other end", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1
Referring to fig. 1, an embodiment of the present invention: the high-performance steam-curing-free maintenance shield segment has the construction flow of assembling a mould → spraying a release agent → installing a steel reinforcement cage → pouring concrete → collecting water from an outer arc surface → demoulding the segment → inspecting finished products, and is characterized in that: the method comprises the following six steps:
the method comprises the following steps: the module assembling: before the die is assembled, checking all positions of the die, unfolding and pulling out all bolts according to the sequence of closing an end template firstly and closing a side die secondly when the side die is closed, installing fixing bolts of a bottom die and the side die, screwing the fixing bolts by hands firstly, then screwing the fixing bolts from the middle to the two ends in sequence by using a special tool, and adding a release agent into the die after the assembly is finished;
step two: and (3) installing the reinforcement cage: the steel reinforcement framework is welded and molded, the phenomena of meat biting, false welding and slag inclusion cannot occur to welding seams, the length and the height of the welding seams must meet the design requirements, the number of the brackets of the concrete protective layer of the steel reinforcement framework, the height of the protective layer, the number of the installed embedded parts and the attaching degree of the embedded parts and the mold are checked, and the concrete protective layer is installed into the mold after the error is confirmed;
step three: pouring the concrete: the new concrete is poured into the segment mould by pneumatic integral vibration, the content of gas in the concrete is reduced to the maximum extent, when the temperature is lower than 25 ℃, the interval time of the concrete discharged from a mixer and transported and poured into the mould is not longer than 3 hours, and when the temperature is higher than 25 ℃, the interval time is not longer than 2.5 hours, the pneumatic integral vibration is adopted for concrete forming, the content of gas in the concrete is reduced to the maximum extent, but the concrete is easy to separate into layers and float on the surface when the vibration is too long, so the concrete is fed in three layers when in use, the high-frequency vibration is adopted when the concrete is poured into the mould, then the low-frequency vibration is adopted after the feeding, the vibration time and the vibration frequency of each time are adjusted according to the working performance of the concrete, the total vibration time is controlled within ten minutes, the layered feeding vibration mode can stop the over-vibration and separate into layers of the concrete, and simultaneously the void ratio and the gas content of the concrete can be reduced as much as possible, the quality problems of honeycomb pitted surface and the like on the surface of the duct piece are avoided;
step four: the outer arc surface receives water: after concrete pouring, a pressing plate can be removed at intervals according to the air temperature, the water collecting process of the outer arc surface of the duct piece is carried out, the outer arc surface collects water, redundant concrete is scraped by a scraping plate, the arc surface of the duct piece and the outer arc of a steel mould are kept smooth and flat, a pull ruler is used for leveling and compacting, iron plates are used for oil polishing, and then secondary water collection of the outer arc surface of the duct piece is carried out at intervals according to the air temperature;
step five: demolding of the duct piece: a horizontal lifting appliance is adopted for demoulding the shield segment, after the strength of the segment is more than 20MPa, a side plate needs to be firstly disassembled in the demoulding process (namely, a vacuum sucker is 15 MPa), and then an end mould needs to be disassembled, so that the damage phenomenon during the mould disassembling of the segment can be avoided, and the whole mould disassembling process cannot be forcibly disassembled;
step six: and (3) inspecting the finished product: the single-piece duct piece needs to use a vernier caliper to measure the precision, three points are respectively measured on the width of the inner cambered surface and the width of the outer cambered surface, the allowable error is 0.5mm, three points are measured on the thickness, the allowable error is plus 3 to minus 1mm, the chord arc length is plus or minus 1.5mm, the duct piece leakage detection test is qualified under the action of the water pressure of 0.8MPa of leakage detection pressure and the constant pressure for 6 hours, and the penetration depth is less than 5 cm.
Further, the steel mould is cleared up thoroughly when being assembled, concrete residues are completely removed, the surface of the steel mould contacted with the concrete is flushed by compressed air, the steel mould is not required to be knocked by a hammer and chiseled by a chisel, the steel mould is removed along the surface of the steel mould, the surface damage of the steel mould is strictly prevented, the width of the steel mould is measured by an inside micrometer, and quality detection personnel are required to detect and record the size of the clean width in the steel mould after the folding work of each steel plate of the mould is completed, so that the accuracy of the device is improved.
Furthermore, before the release agent is sprayed, whether residual concrete exists on the inner surface of the mold needs to be checked, after the confirmation, a water-soluble release agent is selected for spraying, and when the release agent is sprayed, a mist sprayer is used for spraying, and then the mop is used for uniformly coating.
Furthermore, the single steel bar sheet and the framework in the second step are formed by adopting a low-temperature welding process, and when the bent core rod is assembled, fastening of a tightening device of the bent core rod is ensured if necessary, so that the risk that the bent core rod falls off when pouring vibration is carried out, and mortar is poured into the bolt hole to cause silting and the like is avoided.
Further, after the maintenance of the duct piece is completed, the type, the mark, the model, the production serial number, the production date and the inspection state of the duct piece are marked on the side surface of the duct piece and the upper right corner of the inner arc surface, and the duct piece is placed on 3 hard square timbers of 0.1m × 0.1.1 m after the marking is completed and transported to a construction site for assembly.
Furthermore, the lubrication of each clamping position, each bolt connecting point and each running position of the steel die are detected at regular time, and the bolts, the positioning mechanisms and the bent bolts are fastened by injecting butter periodically, otherwise, the opening and closing of the die are easily caused, so that the working effect is reduced, and the application life of the die is shortened.
Example 2
Firstly, a duct piece concrete preparation process:
the shield segment is a main assembly component for shield construction, is an innermost barrier of a tunnel and plays roles of resisting soil layer pressure, underground water pressure and some special loads, the shield segment is a permanent lining structure of a shield method tunnel, at present, most of domestic concrete segments are steam cured to heat concrete by utilizing the heat-moisture effect of steam and accelerate the hardening process of concrete, so that the early strength of the segment concrete rapidly reaches the lifting and demoulding strength to accelerate the turnover of a mould and improve the production efficiency of the segment, but the steam curing can also generate certain negative effects on the concrete on the premise of improving the early hardening speed of the concrete.
1. The concrete mainly comprises the following components: the method comprises the following steps:
the method comprises the following steps: preparing raw materials: cement, fly ash: the grade I fly ash with the fineness of 10.1 percent, the water demand ratio of 94 percent, the ignition loss of 1.93 percent, the coarse aggregate, the fine aggregate and the admixture are selected: the polycarboxylic acid Shanghai Sanrui VIVIID-500A early strength polycarboxylic acid water reducing agent has the gas content of 2 percent and the water reducing rate of 28 to 30 percent, and the water content is as follows: the underground water meets the standard requirements on the water for the concrete mixture in JGJ 63-2006;
step two: raw material proportion: cement: fine aggregate: coarse aggregate: water: additive: the fly ash is 370:690:1170:130:7.79:65(kg), and in order to ensure the strength and durability of the segment concrete, the raw materials are selected to meet the requirements except for the indexes such as strength, gradation and the like;
step three: mixing and stirring: adding raw materials of cement, coarse aggregate, fine aggregate and fly ash in a specified proportion into a concrete stirrer, fully stirring, adding water in a specified amount after uniformly stirring, fully stirring for 10-30 min, and adding an additive after completion, fully stirring and mixing until uniform;
step four: detection and filling: the concrete which is mixed and stirred uniformly is transported to the position of the mould by utilizing a transport vehicle for sampling and inspection, and the slump forming can be carried out after the inspection is qualified, and the slump is controlled within 35-40 mm.
Furthermore, in a low-temperature season, a plurality of early strength components can be properly added into the admixture, the time for filling steam is reduced, and in a high-temperature season construction, the early strength components can be properly reduced, so that on the premise of ensuring the demolding strength, the early high strength is not excessively pursued, and the early hydration heat of the concrete is not too high, the temperature tensile stress occurs, and the outer arc surface of the pipe piece is cracked.
Furthermore, the cement is low-alkali cement P.O 42.5, the compressive strength reaches 27.9MPa and 49.6MPa respectively in 3 days and 28 days, and the flexural strength reaches 6.2MPa and 8.9MPa respectively.
Furthermore, the coarse aggregate is continuously prepared with crushed stone of 5-25 mm, the crushing index is 10.3%, the needle sheet content is 7%, the mud content is 0.4%, the mud block content is 0.1%, the fine aggregate is Dongguan river sand, zone II, the fineness modulus is 2.5, the mud content is 0.4%, the mud block content is 0.1%, and the chloride ion content is 0.002%.
To summarize: according to the shield segment, the polycarboxylic acid Shanghai Sanrui VIVIID-500A early-strength polycarboxylic acid water reducing agent is adopted to prepare the non-autoclaved segment concrete, the initial slump of the concrete is 40mm, the concrete finishing and plastering time is 75min, the 12h strength meets the requirement of formwork removal, the surface bubbles are less, and under the condition of meeting the requirements of specification and strength, the cement consumption is reduced to the maximum extent, a large amount of admixture (mainly fly ash and mineral powder) is used, the hydration heat of the cement in the early stage of hydration is reduced, the crack resistance and the volume stability of the concrete are improved, and the cost of the concrete is effectively reduced.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Claims (6)
1. The high-performance steam-curing-free maintenance shield segment has the construction flow of assembling a mould → spraying a release agent → installing a steel reinforcement cage → pouring concrete → collecting water from an outer arc surface → demoulding the segment → inspecting finished products, and is characterized in that: the method comprises the following six steps:
the method comprises the following steps: the module assembling: before the die is assembled, checking all positions of the die, unfolding and pulling out all bolts according to the sequence of closing an end template firstly and closing a side die secondly when the side die is closed, installing fixing bolts of a bottom die and the side die, screwing the fixing bolts by hands firstly, then screwing the fixing bolts from the middle to the two ends in sequence by using a special tool, and adding a release agent into the die after the assembly is finished;
step two: and (3) installing the reinforcement cage: the steel reinforcement framework is welded and molded, the phenomena of meat biting, false welding and slag inclusion cannot occur to welding seams, the length and the height of the welding seams must meet the design requirements, the number of the brackets of the concrete protective layer of the steel reinforcement framework, the height of the protective layer, the number of the installed embedded parts and the attaching degree of the embedded parts and the mold are checked, and the concrete protective layer is installed into the mold after the error is confirmed;
step three: pouring the concrete: the method comprises the following steps of pouring newly-prepared concrete into a duct piece mould by adopting pneumatic integral vibration, reducing the content of gas in the concrete to the maximum extent, wherein when the temperature is lower than 25 ℃, the interval time of discharging the concrete from a stirrer and pouring the concrete into the mould after transportation is not longer than 3 hours, and when the temperature is higher than 25 ℃, the interval time is not longer than 2.5 hours;
step four: the outer arc surface receives water: after concrete pouring, a pressing plate can be removed at intervals according to the air temperature, the water collecting process of the outer arc surface of the duct piece is carried out, the outer arc surface collects water, redundant concrete is scraped by a scraping plate, the arc surface of the duct piece and the outer arc of a steel mould are kept smooth and flat, a pull ruler is used for leveling and compacting, iron plates are used for oil polishing, and then secondary water collection of the outer arc surface of the duct piece is carried out at intervals according to the air temperature;
step five: demolding of the duct piece: a horizontal lifting appliance is adopted for demoulding the shield segment, after the strength of the segment is more than 20MPa, a side plate needs to be firstly disassembled in the demoulding process (namely, a vacuum sucker is 15 MPa), and then an end mould needs to be disassembled, so that the damage phenomenon during the mould disassembling of the segment can be avoided, and the whole mould disassembling process cannot be forcibly disassembled;
step six: and (3) inspecting the finished product: the single-piece duct piece needs to use a vernier caliper to measure the precision, three points are respectively measured on the width of the inner cambered surface and the width of the outer cambered surface, the allowable error is 0.5mm, three points are measured on the thickness, the allowable error is plus 3 to minus 1mm, the chord arc length is plus or minus 1.5mm, the duct piece leakage detection test is qualified under the action of the water pressure of 0.8MPa of leakage detection pressure and the constant pressure for 6 hours, and the penetration depth is less than 5 cm.
2. The high-performance steam-curing-free maintenance shield segment according to claim 1, characterized in that: the steel mould is cleaned thoroughly when being assembled, concrete residues are removed completely, the surface of the steel mould contacted with concrete is cleaned by compressed air, the steel mould is not required to be knocked by a hammer and chiseled by a chisel, the steel mould is removed along the surface of the steel mould, the surface of the steel mould is prevented from being damaged strictly, and the width of the steel mould is measured by an inside micrometer.
3. The high-performance steam-curing-free maintenance shield segment according to claim 1, characterized in that: before the release agent is sprayed, whether residual concrete exists on the inner surface of the mold needs to be checked, after the confirmation, the water-soluble release agent is selected for spraying, and when the release agent is sprayed, a mist sprayer is used for spraying, and then the mop is used for uniformly coating.
4. The high-performance steam-curing-free maintenance shield segment according to claim 1, characterized in that: and in the second step, the single steel bar sheets and the framework are formed by adopting a low-temperature welding process, and when the bent core rod is assembled, fastening of a tightening device of the bent core rod is ensured if necessary so as to avoid the risk that the bent core rod falls off when pouring vibration occurs, and mortar is poured into the bolt hole to cause silting and the like.
5. The high-performance steam-curing-free maintenance shield segment as claimed in claim 1, wherein after maintenance of the segment is completed, segment types, marks, models, production serial numbers, production dates and inspection states are marked on the side faces of the segment and the upper right corner of the intrados, and after the marks are completed, the segment is placed on 3 hard square timbers of 0.1m × 0.1.1 m and transported to a construction site for assembly.
6. The high-performance steam-curing-free maintenance shield segment according to claim 1, characterized in that: the lubrication of each clamping position, each bolt connecting point and each running position of the steel die are detected at regular time, and the bolts, the positioning mechanisms and the bent bolts are fastened by injecting butter periodically, otherwise, the opening and closing of the die are easily caused, so that the working effect is reduced, and the application period of the die is shortened.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112873000A (en) * | 2021-01-12 | 2021-06-01 | 南通铁建建设构件有限公司 | High-performance steam-free maintenance shield segment and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011152694A (en) * | 2010-01-27 | 2011-08-11 | Pnc:Kk | Method for manufacturing bent pipe |
| CN105565720A (en) * | 2015-12-16 | 2016-05-11 | 广东红墙新材料股份有限公司 | Application of super early strength polycarboxylate superplasticizer to segment |
| CN105565719A (en) * | 2015-12-16 | 2016-05-11 | 广东红墙新材料股份有限公司 | Application of super early strength polycarboxylate superplasticizer to segment |
| CN108793805A (en) * | 2018-08-30 | 2018-11-13 | 江苏金木土科技有限公司 | Concrete admixture formula of steam-curing-free high-impermeability shield segment and curing process thereof |
| CN109732772A (en) * | 2018-12-30 | 2019-05-10 | 中铁十四局集团有限公司 | The method for prefabricating of section of jurisdiction and section of jurisdiction |
-
2020
- 2020-03-27 CN CN202010228246.XA patent/CN111361003A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011152694A (en) * | 2010-01-27 | 2011-08-11 | Pnc:Kk | Method for manufacturing bent pipe |
| CN105565720A (en) * | 2015-12-16 | 2016-05-11 | 广东红墙新材料股份有限公司 | Application of super early strength polycarboxylate superplasticizer to segment |
| CN105565719A (en) * | 2015-12-16 | 2016-05-11 | 广东红墙新材料股份有限公司 | Application of super early strength polycarboxylate superplasticizer to segment |
| CN108793805A (en) * | 2018-08-30 | 2018-11-13 | 江苏金木土科技有限公司 | Concrete admixture formula of steam-curing-free high-impermeability shield segment and curing process thereof |
| CN109732772A (en) * | 2018-12-30 | 2019-05-10 | 中铁十四局集团有限公司 | The method for prefabricating of section of jurisdiction and section of jurisdiction |
Non-Patent Citations (2)
| Title |
|---|
| 董铁良: "关于盾构管片生产工艺流程的研究 ", 《工程质量》 * |
| 董铁良: "关于盾构管片生产工艺流程的研究", 《工程质量》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112873000A (en) * | 2021-01-12 | 2021-06-01 | 南通铁建建设构件有限公司 | High-performance steam-free maintenance shield segment and preparation method thereof |
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