CN114262203A - Special grouting material for tunnel grouting construction with mold and application thereof - Google Patents
Special grouting material for tunnel grouting construction with mold and application thereof Download PDFInfo
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- CN114262203A CN114262203A CN202111479800.2A CN202111479800A CN114262203A CN 114262203 A CN114262203 A CN 114262203A CN 202111479800 A CN202111479800 A CN 202111479800A CN 114262203 A CN114262203 A CN 114262203A
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- 239000000463 material Substances 0.000 title claims abstract description 62
- 238000010276 construction Methods 0.000 title claims abstract description 33
- 239000004568 cement Substances 0.000 claims abstract description 31
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000002156 mixing Methods 0.000 claims abstract description 24
- 239000002994 raw material Substances 0.000 claims abstract description 22
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 15
- 239000011575 calcium Substances 0.000 claims abstract description 15
- 239000010881 fly ash Substances 0.000 claims abstract description 15
- PASHVRUKOFIRIK-UHFFFAOYSA-L calcium sulfate dihydrate Chemical compound O.O.[Ca+2].[O-]S([O-])(=O)=O PASHVRUKOFIRIK-UHFFFAOYSA-L 0.000 claims abstract description 11
- 239000011398 Portland cement Substances 0.000 claims abstract description 7
- 239000000654 additive Substances 0.000 claims abstract description 5
- 230000000996 additive effect Effects 0.000 claims abstract description 5
- 239000003795 chemical substances by application Substances 0.000 claims description 38
- 238000007569 slipcasting Methods 0.000 claims description 16
- 239000004034 viscosity adjusting agent Substances 0.000 claims description 9
- 229920001479 Hydroxyethyl methyl cellulose Polymers 0.000 claims description 8
- 239000003638 chemical reducing agent Substances 0.000 claims description 8
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 8
- 229920002401 polyacrylamide Polymers 0.000 claims description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 2
- 229910001586 aluminite Inorganic materials 0.000 claims description 2
- 239000000395 magnesium oxide Substances 0.000 claims description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 2
- 239000011347 resin Substances 0.000 claims description 2
- 229920005989 resin Polymers 0.000 claims description 2
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- 239000010703 silicon Substances 0.000 claims description 2
- 238000003780 insertion Methods 0.000 description 20
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- 150000001875 compounds Chemical class 0.000 description 4
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- 238000010998 test method Methods 0.000 description 4
- 239000002390 adhesive tape Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 3
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- 238000002360 preparation method Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 230000000740 bleeding effect Effects 0.000 description 2
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- 239000000203 mixture Substances 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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Abstract
The invention relates to the technical field of tunnel strip mold grouting construction, in particular to a special grouting material for tunnel strip mold grouting construction and application thereof, wherein the grouting material is formed by mixing raw materials with water; the raw materials comprise: 90-150 parts of cement, 20-30 parts of fine aggregate, 26-44 parts of additive, 20-30 parts of high-calcium fly ash, 5-15 parts of calcined shale and 30-35 parts of phosphogypsum; the cement is formed by mixing 40-70 parts of ordinary Portland cement and 50-80 parts of quick-hardening sulphoaluminate cement; the high-calcium fly ash, the calcined shale and the phosphogypsum are added in a certain proportion, so that the later strength of the grouting material is favorably improved, and the stability of the grouting material is improved; the high-calcium fly ash is used as an expansion source of one of grouting materials, and can obviously improve the later strength, the impermeability and the durability of the grouting material through the characteristics of the high-calcium fly ash.
Description
Technical Field
The invention relates to the technical field of tunnel strip mold grouting construction, in particular to special grouting material for tunnel strip mold grouting construction and application thereof.
Background
In the tunnel construction process, the excavation working face needs to be quickly subjected to primary lining to construct a foundation structure so as to provide an original supporting structure; after the tunnel is excavated to a certain degree, secondary lining construction is carried out to form a standard supporting structure in the tunnel so as to provide a reliable and firm supporting structure for the tunnel after being formed; the lining can bear larger loose pressure of surrounding rocks, and can play an active limiting role in deformation of the surrounding rocks and primary support.
The expansion rate of the existing lining grouting material is low, and the phenomenon of void exists behind the lining of the tunnel after the lining grouting material is condensed, so that the safety performance of the tunnel is directly influenced, and huge potential safety hazards are caused.
Disclosure of Invention
Aiming at the defects that the expansion rate of a grouting material is low and the tunnel lining has a void phenomenon in the prior art, the invention provides a special grouting material for tunnel strip mold grouting construction and application thereof. The expansion rate of the grouting material can be improved, so that the phenomenon of void is avoided.
In order to solve the above technical problems, the present invention is solved by the following technical solutions.
A special grouting material for tunnel grouting construction with a mold is prepared by mixing raw materials with water; the raw materials comprise the following components:
90-150 parts of cement, 20-30 parts of fine aggregate, 26-44 parts of additive, 20-30 parts of high-calcium fly ash, 5-15 parts of calcined shale and 30-35 parts of phosphogypsum; the cement is prepared by mixing 40-70 parts of ordinary Portland cement and 50-80 parts of quick-hardening sulphoaluminate cement.
Preferably, the additive comprises 10-12 parts of viscosity modifier, 2-8 parts of expanding agent, 5-10 parts of early strength agent, 4-6 parts of water reducing agent and 5-8 parts of water retaining agent.
Preferably, the water retention agent is formed by mixing hydroxyethyl methyl cellulose ether and polyacrylamide.
Preferably, the mass ratio of hydroxyethyl methyl cellulose ether to polyacrylamide is 4: 6.
Preferably, the fineness modulus of the fine aggregate is 3.5 to 2.5 and the average particle diameter is 0.65 to 0.4 mm.
Preferably, the raw material and the water are mixed according to the water-material ratio of 0.18, and the outflow fluidity is 230-310 mm.
Preferably, the expanding agent is prepared by mixing aluminite, absolute ethyl alcohol, magnesium oxide and silicon resin in a ratio of 4:2:3:1 in a stirrer, and the average particle size of the expanding agent is 5-12 microns.
The application of the special grouting material for the grouting construction of the tunnel strip mold is to apply the special grouting material for the grouting construction of the tunnel strip mold in the grouting construction of the tunnel strip mold.
The invention has the following beneficial effects:
1. according to the invention, the fine aggregate and the viscosity modifier are added into the grouting material according to a certain proportion, so that the prepared grouting material has better homogeneity and shrinkage rate, and meanwhile, the strength of the grouting material can be further improved, and the use effect of the grouting material after solidification is improved.
2. By adding the expanding agent in a certain proportion, the prepared grouting material has a certain expansion rate, so that the phenomenon of void at the back of the tunnel lining can be better avoided, the construction quality is further ensured, and accidents are avoided.
3. By adding the water-retaining agent, the grouting material formed by combining the water-retaining agent, cement and fine aggregate has better stability, and harmful holes are prevented from being formed in the grouting material in the process of preparing the grouting material, so that the prepared grouting material is more compact, and the using effect is better.
4. The early strength of the grouting material can be improved better by adding the early strength agent.
5. The high-calcium fly ash, the calcined shale and the phosphogypsum are added in a certain proportion, so that the later strength of the grouting material is favorably improved, and the stability of the grouting material is improved; the high-calcium fly ash is used as an expansion source of one of grouting materials, and can obviously improve the later strength, the impermeability and the durability of the grouting material through the characteristics of the high-calcium fly ash.
Drawings
FIG. 1 is a schematic view of a tool body in example 2;
FIG. 2 is a schematic view of the plate A in example 2;
FIG. 3 is a schematic view of the B plate in example 2;
FIG. 4 is a schematic view of a nut cut in embodiment 2;
FIG. 5 is a schematic view of a connecting tube in embodiment 2;
FIG. 6 is a schematic view of a female head in embodiment 2;
FIG. 7 is a schematic view of the male connector according to embodiment 2;
FIG. 8 is a schematic view of a rotating rod in embodiment 2;
FIG. 9 is a schematic view of a rubber ring in example 2;
FIG. 10 is a sectional view of the female head in embodiment 2;
FIG. 11 is a partial sectional view of the tool body in example 2;
FIG. 12 is a schematic view of a quick coupling according to embodiment 3;
FIG. 13 is a schematic view of a female head in embodiment 3;
FIG. 14 is a schematic view of a male connector according to embodiment 3;
FIG. 15 is a schematic view of a first extrusion block of example 3;
FIG. 16 is a schematic view of a second extrusion block of example 3;
FIG. 17 is a schematic view of a third elastic member in embodiment 3;
FIG. 18 is a sectional view of the female head in embodiment 3;
FIG. 19 is a sectional view of a quick coupling of embodiment 3;
FIG. 20 is an enlarged view of a portion of FIG. 19 at A;
fig. 21 is a flowchart of a construction method in example 1.
The names of the parts indicated by the numerical references in the drawings are as follows:
110. RPC tube; 120. a flange plate; 121. a, a plate; 122. b, plate; 123. a fixing ring; 130. a variable-section nut; 131. a hand-held portion; 140. a quick coupling; 141. a connecting pipe; 142. a female head; 143. a male head; 144. a first connecting ring; 145. a second connection ring; 146. a fixing plate; 147. rotating the rod; 210. a communicating hole; 220. a gasket; 410. a first stationary tube; 420. a second stationary tube; 610. a first positioning ring; 710. a second positioning ring; 711. an arc-shaped slot; 810. pressing a plate; 820. a grip; 910. a rubber ring; 1010. a movable groove; 1110. a through hole; 1210. a first fixed block; 1220. a first fixed column; 1230. a second fixed block; 1231. a second connection hole; 1240. a first bar; 1250. a second bar-shaped rod; 1310. a first connection hole; 1320. a first lane; 1410. a second fixed column; 1411. a second bump; 1412. a second groove; 1510. a first extrusion block; 1511. a first bump; 1512. a first reset block; 1513. a first inclined plane; 1610. a second extrusion block; 1611. a first groove; 1612. a second reset block; 1613. a second inclined plane; 1710. a third elastic member; 1810. a jack; 1820. a second lane; 1830. a first reset groove; 1840. a second reset groove; 1850. mounting grooves; 1910. a first elastic member; 1920. a second elastic member.
Detailed Description
For a further understanding of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings and examples. It is to be understood that the examples are illustrative of the invention and not limiting. Example 1
The special grouting material for tunnel strip mold grouting construction is formed by mixing raw materials with water according to a water-material ratio of 0.18; the raw materials comprise the following components:
100 parts of cement, 25 parts of fine aggregate, 10 parts of viscosity modifier, 5 parts of expanding agent, 7 parts of early strength agent, 5 parts of water reducing agent, 6 parts of water retaining agent, 25 parts of high-calcium fly ash, 10 parts of calcined shale and 33 parts of phosphogypsum.
The cement is formed by mixing 45 parts of ordinary portland cement and 55 parts of quick-hardening sulphoaluminate cement; the water-retaining agent is formed by mixing hydroxyethyl methyl cellulose ether and polyacrylamide according to a mass ratio of 4: 6; the fineness modulus of the fine aggregate is 3.5-2.5, and the average particle size is 0.65-0.4 mm.
The stirring is carried out by adopting a stirrer, and the mixture is injected into a void area between the tunnel lining and the waterproof board through a pressurizing grouting pump, so that the problem of vault crown void can be effectively solved.
The performance of the slip casting compound in each example was tested by reference to the following standard: GB/T50448 technical Specification for application of cement-based grouting materials; GB/T50080 Standard test methods for concrete mixture Properties; GB/T17671: "cement mortar Strength test method (ISO method)"; technical requirements for grouting of arch crown with mold of tunnel lining.
Example 2
The special grouting material for tunnel strip mold grouting construction is formed by mixing raw materials with water according to a water-material ratio of 0.18; the raw materials comprise the following components:
120 parts of cement, 30 parts of fine aggregate, 12 parts of viscosity modifier, 7 parts of expanding agent, 8 parts of early strength agent, 5 parts of water reducing agent, 7 parts of water retaining agent, 28 parts of high-calcium fly ash, 12 parts of calcined shale and 32 parts of phosphogypsum.
The cement is formed by mixing 50 parts of ordinary Portland cement and 70 parts of quick-hardening sulphoaluminate cement; the water-retaining agent is formed by mixing hydroxyethyl methyl cellulose ether and polyacrylamide according to a mass ratio of 4: 6; the fineness modulus of the fine aggregate is 3.5-2.5, and the average particle size is 0.65-0.4 mm.
The preparation method and test method of the slip casting compound in this example are the same as those in example 1.
Example 3
The special grouting material for tunnel strip mold grouting construction is formed by mixing raw materials with water according to a water-material ratio of 0.18; the raw materials comprise the following components:
90 parts of cement, 20 parts of fine aggregate, 10 parts of viscosity modifier, 2 parts of expanding agent, 5 parts of early strength agent, 4 parts of water reducing agent, 5 parts of water retaining agent, 20 parts of high-calcium fly ash, 5 parts of calcined shale and 30 parts of phosphogypsum.
The cement is formed by mixing 40 parts of ordinary Portland cement and 50 parts of quick-hardening sulphoaluminate cement; the water-retaining agent is formed by mixing hydroxyethyl methyl cellulose ether and polyacrylamide according to a mass ratio of 4: 6; the fineness modulus of the fine aggregate is 3.5-2.5, and the average particle size is 0.65-0.4 mm.
The preparation method and test method of the slip casting compound in this example are the same as those in example 1.
Example 4
The special grouting material for tunnel strip mold grouting construction is formed by mixing raw materials with water according to a water-material ratio of 0.18; the raw materials comprise the following components:
150 parts of cement, 30 parts of fine aggregate, 12 parts of viscosity modifier, 8 parts of expanding agent, 10 parts of early strength agent, 6 parts of water reducing agent, 8 parts of water retaining agent, 30 parts of high-calcium fly ash, 15 parts of calcined shale and 35 parts of phosphogypsum.
The cement is formed by mixing 70 parts of ordinary Portland cement and 80 parts of quick-hardening sulphoaluminate cement; the water-retaining agent is formed by mixing hydroxyethyl methyl cellulose ether and polyacrylamide according to a mass ratio of 4: 6; the fineness modulus of the fine aggregate is 3.5-2.5, and the average particle size is 0.65-0.4 mm.
The preparation method and test method of the slip casting compound in this example are the same as those in example 1.
Comparative example 1
Compared with the example 1, the grouting material of the comparative example is formed by adding water into raw materials and mixing the raw materials according to the water-material ratio of 0.18; the raw materials comprise the following components: 150 parts of cement, 15 parts of fine aggregate, 12 parts of viscosity modifier, 8 parts of expanding agent, 10 parts of early strength agent, 6 parts of water reducing agent, 8 parts of water retaining agent, 15 parts of high-calcium fly ash, 15 parts of calcined shale and 25 parts of phosphogypsum.
The rest is the same as in example 1.
Comparative example 2
Compared with the example 1, the grouting material of the comparative example is formed by adding water into raw materials and mixing the raw materials according to the water-material ratio of 0.18; the raw materials comprise the following components: 150 parts of cement, 35 parts of fine aggregate, 12 parts of viscosity modifier, 8 parts of expanding agent, 10 parts of early strength agent, 6 parts of water reducing agent, 8 parts of water retaining agent, 35 parts of high-calcium fly ash, 15 parts of calcined shale and 40 parts of phosphogypsum.
The rest is the same as in example 1.
Examples 1 to 4 and comparative examples 1 to 2 were tested, respectively, and the test results are shown in tables 1 and 2 below.
Table 1: fluidity, separation, bleeding rate, swelling rate, impermeability and binding to RPC test results.
Table 2: and testing results of the compressive strength, the breaking strength, the bonding strength with concrete and the mass loss and the strength loss rate after aging for 250 times of freeze-thaw cycles.
As can be seen from the results of table 1 and table 2 above, the grouting materials of examples 1 to 4 of the present invention can significantly improve the bonding strength between the grouting material and lining concrete, especially the rupture strength ratio of 7d, and also significantly improve the bonding property and freeze-thaw resistance with the RPC grouting pipe, and have high strength for 12h without separation and bleeding, compared to the comparative examples 1 to 2. In comparison with comparative example 2, there is a certain degree of performance degradation when the component distribution ratio does not fall within the range of claim 1. In addition, the grouting material of the invention also has good fluidity, good fluidity maintaining effect in 90min and micro-expansibility. In addition, the expansion rate difference values of 24h and 3h of the embodiment 1 and the embodiment 4 are tested, and the result shows that the stability is controllable, so that the volume stability of the grouting material in the later period can be ensured, and further, the generation of cracks in the later period can be better avoided.
Example 5
The embodiment provides application of the special grouting material for tunnel strip mold grouting construction, and the special grouting material for tunnel strip mold grouting construction in the embodiments 1 to 4 is applied to tunnel strip mold grouting construction.
In the embodiment, a special tool is adopted to complete the grouting construction of the tunnel strip mold in the specific application process, as shown in fig. 1-11, the tool comprises a tool body, the tool body comprises an RPC pipe 110 which can extend into a grouting hole and is used for grouting, a flange plate 120 which is sleeved outside the RPC pipe 110 and is connected with the grouting hole, a variable-section nut 130 which is sleeved outside the RPC pipe 110 and is connected with the flange plate 120 at one end, a quick connector 140 which is connected with the other end of the variable-section nut 130, and a grouting machine which is connected with the quick connector 140 through the grouting pipe; the flange plate 120 comprises an A plate 121 with a threaded column on the bottom surface, the A plate 121 is connected with the grouting hole, a B plate 122 is arranged on the bottom surface of the A plate 121, a fixing hole for the threaded column to extend into is formed in the B plate 122, and the threaded column is used for being matched with a nut to fix the B plate 122 on the A plate 121; the A plate 121 and the B plate 122 are provided with communicating holes 210 which are communicated and are used for the RPC pipe 110 to extend into; a gasket 220 for sealing is provided between the a plate 121 and the B plate 122 along the circumferential direction of the communication hole 210; the variable cross nut 130 and the quick coupling 140 are provided therein with passages for communicating the grout pipe with the communication hole 210.
In this embodiment, first, the a plates 121 with the same number as the grouting holes on the trolley are prepared, the existing plurality of grouting holes on the trolley are reamed to match the size of each grouting hole with the size of the a plate 121, and then the a plates 121 and the grouting holes are welded; fixing the B plate 122 on the A plate 121 through a nut, extending the RPC pipe 110 to the waterproof plate through the flange plate 120, marking the position with a marker pen, and then taking down the RPC pipe 110 and the B plate 122; cutting the RPC pipe 110 at the position marked by the marker pen and the length of the RPC pipe 110 in the variable-section nut 130; cutting a U-shaped opening at one end of the RPC pipe 110 by using an angle grinder, penetrating an anti-falling-off detection electric wire into the RPC pipe 110 and fixing the anti-falling-off detection electric wire at the U-shaped opening, so that the end of the anti-falling-off detection electric wire is flush with the corresponding end of the RPC pipe 110; winding the other end of the RPC pipe 110 by using a sealing adhesive tape to form a sealing layer, and sealing the orifice by using a double-sided adhesive tape; then installing a variable-section nut 130 on the other end of the RPC pipe 110; installing a variable-section nut 130 on the flange plate 120, sealing the joint of the variable-section nut 130 and the flange plate 120 by a sealing adhesive tape, and finally fixing the B plate 122 on the A plate 121 by the nut; finally, connecting the grouting pipe with a grout outlet of a grouting machine, and connecting the quick connector 140 with the grouting pipe;
before grouting, the double faced adhesive tape on the RPC pipe 110 is poked open, so that the problem of slurry stringing in the grouting process can be effectively prevented, the grouting operation can be favorably ensured to be smoothly carried out, and the grouting efficiency is improved;
during grouting, the rapid joint 140 is used to quickly connect the grouting pipe with the RPC pipe 110, so that grouting operation can be preferably performed and installation is facilitated; after grouting is finished, the grouting pipe can be preferably separated from the variable-section nut 130 by using the quick connector 140, so that grouting operation is stopped, disassembly is convenient, next grouting operation can be rapidly performed, and grouting operation efficiency can be preferably improved;
after disassembly, the variable-section nut 130 and the quick connector 140 are disassembled for cleaning and recycling;
through the setting of gasket 220 in this embodiment for when fixing B board 122 and A board 121, A board 121 and B board 122 can extrude gasket 220, thereby make and realize the sealed between A board 121 and B board 122 under the effect of gasket 220, thereby make at the slip casting in-process, cement thick liquid can not follow the space between A board 121 and the B board 122 and flow out, guarantee the quality of slip casting operation, thereby further improve the efficiency of slip casting.
In this embodiment, the bottom surface of the B plate 122 is provided with a fixing ring 123 communicating with the communication hole 1110; the variable-section nut 130 comprises a block-shaped handheld part 131, and a first fixing pipe 410 and a second fixing pipe 420 which are annular are respectively arranged at two ends of the handheld part 131; the first fixing tube 410 may be inserted into the fixing ring 123 for fixing the nut 130 to the B plate 122; the second fixing tube 420 is used to cooperate with the quick coupling 140 to achieve the fixation of the quick coupling 140 on the truncated nut 130; a through hole 1110 communicating the first fixing tube 410 and the second fixing tube 420 is provided in the hand-held portion 131.
In this embodiment, after the sealing tapes are wound around the first fixing tube 410 and the second fixing tube 420, the first fixing tube 410 is inserted into the fixing ring 123, so as to connect the variable cross nut 130 to the flange plate 120; through the setting with the fixed pipe 420 of second for quick-operation joint 140 can be preferably connected on becoming nut 130, thereby under the effect that becomes nut 130, make the slip casting pipe of being connected with quick-operation joint 140 can communicate with RPC pipe 110 better, thereby can carry out the slip casting operation better.
In this embodiment, the quick connector 140 includes a connecting tube 141 having one end connected to the variable cross nut 130, a female head 142 connected to the other end of the connecting tube 141, and a male head 143 having one end connected to the female head 142 and the other end connected to the grouting tube; the inner side wall of one end of the connecting pipe 141 is connected with the outer side wall of the second fixing pipe 420 through threads; the female head 142 comprises a first annular connecting ring 144, and a first annular positioning ring 610 which can extend into the connecting pipe 141 is arranged at the end part of the first connecting ring 144 close to the connecting pipe 141; the outer side wall of the first positioning ring 610 is in threaded connection with the inner side wall of the connecting pipe 141; the male head 143 comprises a second connection ring 145 in a circular ring shape, and the end of the second connection ring 145 close to the first connection ring 144 is provided with a second positioning ring 710 capable of extending into the first connection ring 144; the first connecting ring 144 and the second positioning ring 710 are connected by a fastening mechanism, and the fastening mechanism is used for realizing the dismounting of the male head 143 on the female head 142; the snap mechanism includes a first retaining ring 610 having an inner diameter less than the inner diameter of the first connecting ring 144; at least two fixing plates 146 are arranged on the outer side wall of the first connecting ring 144, and a rotating rod 147 is rotatably arranged between the two fixing plates 146; the outer side wall of the first connecting ring 144 is provided with a movable groove 1010 along the axial direction of the first connecting ring 144, into which the rotating rod 147 extends, and the movable groove 1010 is communicated with the inner side wall of the first connecting ring 144; an annular arc-shaped groove 711 into which the rotating rod 147 extends is formed in the outer side wall of the second positioning ring 710 along the circumferential direction of the second positioning ring 710; the rotating rod 147 is adapted to compress against the arcuate slot 711 to effect securement of the second retaining ring 710 within the first attachment ring 144.
In this embodiment, the second fixing tube 420 is inserted into the connection tube 141 to fix the connection tube 141 to the nut 130, and the first positioning ring 610 is wound with a sealing tape and inserted into the connection tube 141 to fix the female head 142 to the connection tube 141; the second connection ring 145 is wound with a sealing tape and connected with the grouting pipe;
when grouting starts, firstly, the second positioning ring 710 extends into the first connecting ring 144, the rotating rod 147 is rotated to extrude the arc-shaped groove 711, so that the second positioning ring 710 and the first positioning ring 610 are extruded, the male head 143 is fixed in the female head 142, installation is facilitated, and the first positioning ring 610 and the second positioning ring 710 are extruded to play a role in sealing simultaneously, so that accidents cannot occur in the grouting process, and the grouting operation efficiency is improved;
after the grouting is finished, the rotating rod 147 is rotated reversely, so that the extrusion of the arc-shaped groove 711 by the rotating rod 147 is released, the male head 143 is released from being fixed on the female head 142, and the male head 143 can be taken out conveniently and detached conveniently.
In this embodiment, a rubber ring 910 which is annular and used for sealing is disposed between the first positioning ring 610 and the second positioning ring 710; the rotating rod 147 comprises a pressure plate 810 and a grip 820 which are in a long strip shape, and the pressure plate 810 is connected with the end part of the grip 820; the pressing plate 810 is rotatably connected with the fixing plate 146, and the end of the pressing plate 810 far away from the handle 820 penetrates through the movable groove 1010 and extends into the arc-shaped groove 711 for being pressed with the arc-shaped groove 711.
Through the arrangement of the rubber ring 910 in this embodiment, the rotating rod 147 drives the second positioning ring 710 to extrude the rubber ring 910 while extruding the arc-shaped groove 711, so that the connection of the male head 143 on the female head 142 can be further reinforced under the action of the rubber ring 910, and meanwhile, the rubber ring 910 further plays a role in sealing, thereby further ensuring the smooth operation of grouting operation and improving the working efficiency of grouting operation;
in this embodiment, the pressing plate 810 and the grip 820 are disposed obliquely, and an included angle between the pressing plate 810 and the grip 820 is an obtuse angle; the rotation of the pressing plate 810 is driven by the rotation of the grip 820, so that the operation of a worker can be facilitated; by the arrangement of the pressing plate 810, the arc-shaped groove 711 can be preferably pressed, so that the male head 143 can be preferably fixed on the female head 142.
When the tool for grouting construction of a tunnel strip mold in the embodiment is used specifically, firstly, the A plate 121 and the grouting hole are welded; fixing the B plate 122 on the A plate 121 through a nut, extending the RPC pipe 110 to the waterproof plate through the flange plate 120, marking the position with a marker pen, and then taking down the RPC pipe 110 and the B plate 122; cutting the RPC pipe 110 at the position marked by the marker pen and the length of the RPC pipe 110 in the variable-section nut 130; cutting a U-shaped opening at one end of the RPC pipe 110 by using an angle grinder, penetrating an anti-falling-off detection electric wire into the RPC pipe 110 and fixing the anti-falling-off detection electric wire at the U-shaped opening, so that the end of the anti-falling-off detection electric wire is flush with the corresponding end of the RPC pipe 110; winding the other end of the RPC pipe 110 by using a sealing adhesive tape to form a sealing layer, and sealing the orifice by using a double-sided adhesive tape; then installing a variable-section nut 130 on the other end of the RPC pipe 110; installing a variable-section nut 130 on the flange plate 120, sealing the joint of the variable-section nut 130 and the flange plate 120 by a sealing adhesive tape, and finally fixing the B plate 122 on the A plate 121 by the nut; and finally, connecting the grouting pipe with a grout outlet of the grouting machine, and connecting the quick connector 140 with the grouting pipe.
Example 6
As shown in fig. 12 to 20, the present embodiment provides a quick coupling 140 used in embodiment 5, the quick coupling 140 including a female head 142 and a male head 143; the female head 142 comprises a first fixing block 1210, a square insertion hole 1810 is formed in the first fixing block 1210 in the axial direction of the first fixing block 1210, and the insertion hole 1810 penetrates through the first fixing block 1210; a first fixing column 1220 is arranged at one end of the first fixing block 1210, a first connecting hole 1310 communicated with the insertion hole 1810 is arranged in the first fixing column 1220, the first connecting hole 1310 is arranged along the axial direction of the first fixing column 1220, and the first connecting hole 1310 penetrates through the first fixing column 1220; the first fixing column 1220 is used for cooperating with the variable cross-section nut 130 to fix the female head 142 on the variable cross-section nut 130; the male head 143 comprises a second fixing block 1230 connected with the grouting pipe, and a second fixing column 1410 which can extend into the insertion hole 1810 is arranged at one end of the second fixing block 1230; second connection holes 1231 communicated with the first connection holes 1310 are formed in the second fixing block 1230 and the second fixing column 1410; a limiting mechanism is arranged between the first fixing block 1210 and the second fixing column 1410, and the limiting mechanism is used for fixing and sealing the male head 143 on the female head 142.
In this embodiment, the first fixing column 1220 on the female head 142 is connected with the variable cross nut 130 through a thread, and then the second fixing block 1230 on the male head 143 is connected with the grouting pipe;
during grouting, the male head 143 can be fixed on the female head 142 under the action of the limiting mechanism only by extending the male head 143 into the jack 1810, so that grouting operation is performed, and installation is facilitated;
after grouting, the male head 143 can be preferably taken out of the jack 1810 by operating the limiting mechanism, so that the disassembly is convenient;
through stop gear's setting, can realize the dismouting between public head 143 and the female head 142 better, can carry out the slip casting operation next time fast to can improve the efficiency of slip casting operation better.
In this embodiment, the limiting mechanism includes a first squeezing block 1510 and a second squeezing block 1610 disposed in the receptacle 1810, the first squeezing block 1510 and the second squeezing block 1610 are disposed opposite to each other along a direction perpendicular to an axial direction of the first fixing post 1220, the first squeezing block 1510 and the second squeezing block 1610 are movable along the direction perpendicular to the axial direction of the first fixing post 1220 in the receptacle 1810, and the first squeezing block 1510 is used for squeezing the second squeezing block 1610 to close the first connection hole 1310; a first runner 1320 and a second runner 1820 which are communicated with the insertion hole 1810 are arranged in the first fixing block 1210; a first bar-shaped rod 1240 is movably arranged in the first runner 1320, one end of the first bar-shaped rod 1240 extends into the insertion hole 1810 and is connected with the first extrusion block 1510, and the other end of the first bar-shaped rod 1240 extends out of the first runner 1320; a second bar-shaped rod 1250 is movably arranged in the second street 1820, one end of the second bar-shaped rod 1250 extends into the insertion hole 1810 and is connected with the second extrusion block 1610, and the other end of the second bar-shaped rod 1250 extends out of the second street 1820; the first and second bar-shaped bars 1240, 1250 are used to effect movement of the first and second crush blocks 1510, 1610 within the socket 1810; a first reset groove 1830 is formed by inward recessing on the inner side wall of the first runner 1320, a first reset block 1512 extending into the first reset groove 1830 is disposed on the first bar-shaped bar 1240, the first reset block 1512 and the first reset groove 1830 are connected by a first elastic element 1910, and the first elastic element 1910 is used for maintaining the tendency of the first reset block 1512 moving toward the insertion hole 1810; the inner side wall of the second street 1820 is recessed inwards to form a second reset groove 1840, the second bar-shaped bar 1250 is provided with a second reset block 1612 extending into the second reset groove 1840, the second reset block 1612 and the second reset groove 1840 are connected through a second elastic member 1920, and the second elastic member 1920 is used for keeping the tendency that the second reset block 1612 moves towards the direction of the insertion hole 1810; the first elastic member 1910 is a spring; the second elastic member 1920 is a spring.
In this embodiment, when not in use, the spring is in an extended state, so that the first and second reset blocks 1512 and 1612 respectively drive the first and second bar-shaped rods 1240 and 1250 to extrude the first and second extrusion blocks 1510 and 1610, so that the first and second extrusion blocks 1510 and 1610 are extruded, thereby plugging the first connection hole 1310;
when grouting, firstly, a worker pulls the first strip-shaped rod 1240 and the second strip-shaped rod 1250 to enable the first resetting block 1512 and the second resetting block 1612 to squeeze the spring, and simultaneously enables the first squeezing block 1510 and the second squeezing block 1610 to move in the insertion hole 1810, so that the second fixing column 1410 can extend into a position between the first squeezing block 1510 and the second squeezing block 1610, and finally, the worker loosens the first strip-shaped rod 1240 and the second strip-shaped rod 1250 to enable the first squeezing block 1510 and the second squeezing block 1610 to tightly press the second fixing column 1410 under the action of the spring, so that the second fixing column 1410 is fixed in the insertion hole, and a sealing effect is achieved while the first squeezing block 1510 and the second squeezing block 1610 squeeze the second fixing column 1410, so that the operation and installation of the worker are facilitated;
after grouting is finished, the male head 143 can be detached from the female head 142 only by pulling the male head 143.
In this embodiment, an end surface of the first extrusion block 1510 contacting with the second extrusion block 1610 is provided with a first protrusion 1511 in an elongated shape; a first groove 1611 for the first protrusion 1511 to be clamped in is arranged at a position of the second pressing block 1610 corresponding to the first protrusion 1511; the first protrusion 1511 is used to cooperate with the first recess 1611 to further block the first connection hole 1310; the outer side wall of the second fixing column 1410 is provided with a second projection 1411 and a second groove 1412, and the second projection 1411 and the second groove 1412 are respectively used for being matched with the first groove 1611 and the first projection 1511 to fix the second fixing column 1410 in the insertion hole 1810.
In this embodiment, through the arrangement of the first protrusion 1511, the first groove 1611, the second protrusion 1411 and the second groove 1412, when grouting is performed, after a worker pulls the first pressing block 1510 and the second pressing block 1610 open and extends the second fixing column 1410 into the first pressing block 1510 and the second pressing block 1610 are released by the worker, the first protrusion 1511 is clamped into the second groove 1412, and the second protrusion 1411 is clamped into the first groove 1611, so that the second fixing column 1410 is fixed, and under the reverse thrust of cement slurry, the second fixing column 1410 cannot fall off from the insertion hole 1810, thereby ensuring smooth performance of grouting;
after grouting is finished, the worker pulls the first extrusion block 1510 and the second extrusion block 1610 open to move the first protrusion 1511 out of the second groove 1412 and move the second protrusion 1411 out of the first groove 1611, so that the fixation of the second fixing column 1410 is released, and the male head 143 is detached, and after the worker loosens the first bar 1240 and the second bar 1250, the first protrusion 1511 extends into the first groove 1611 again under the action of the spring, at this time, the first connection hole 1310 is sealed by mutual extrusion of the first extrusion block 1510 and the second extrusion block 1610, and meanwhile, a second seal is formed under the action of the first protrusion 1511 and the first groove 1611, so that the sealing effect is better, thereby preventing cement slurry from leaking out, and further improving the efficiency of grouting operation.
In this embodiment, the first pressing block 1510 is provided with a first inclined surface 1513, the second pressing block 1610 is provided with a second inclined surface 1613, and the first inclined surface 1513 and the second inclined surface 1613 are used for pressing the second fixing column 1410 to realize the quick assembly and disassembly of the second fixing column 1410 in the insertion hole 1810; an installation groove 1850 for the second fixing column 1410 to extend into is arranged on the inner side wall of the first connection hole 1310 close to the first fixing block 1210, the installation groove 1850 is arranged along the circumferential direction of the first connection hole 1310, a third elastic piece 1710 is arranged in the installation groove 1850, and the third elastic piece 1710 is used for keeping the tendency that the second fixing column 1410 moves towards the outside of the installation groove 1850; third resilient member 1710 is a rubber pad.
Through the arrangement of the first inclined surface 1513 and the second inclined surface 1613 in this embodiment, when grouting is performed, the second fixing column 1410 is firstly extended into the insertion hole 1810, and at this time, a worker does not need to pull the first bar-shaped rod 1240 and the second bar-shaped rod 1250, under the action of the first inclined surface 1513 and the second inclined surface 1613, the second fixing column 1410 is firstly contacted with the first inclined surface 1513 and the second inclined surface 1613 when extending into the insertion hole 1810, and then the first inclined surface 1513 and the second inclined surface 1613 are squeezed, so that the first squeezing block 1510 and the second squeezing block 1610 are separated during the squeezing process of the first inclined surface 1513 and the second inclined surface 1613, and then the second fixing column 1410 is conveniently extended into the insertion hole 1810, which is convenient for the worker to operate and install;
after grouting is finished, firstly, a worker pulls the first pressing block 1510 and the second pressing block 1610 apart to enable the second fixing column 1410 to move, in the process that the second fixing column 1410 moves out of the insertion hole 1810, under the action of a spring, the first inclined surface 1513 and the second inclined surface 1613 continue to press the edge of the second fixing column 1410 while the second fixing column 1410 moves, so that cement slurry does not leak out in the process that the second fixing column 1410 moves out, after the second fixing column 1410 moves to a certain distance, the first pressing block 1510 and the second pressing block 1610 squeeze again to seal the first connection hole 1310, and then when the second fixing column 1410 continues to move out of the insertion hole 1810, the first inclined surface 1513 and the second inclined surface 1613 do not squeeze with the second fixing column 1410 any more until the second fixing column 1410 completely moves out of the insertion hole 1810;
under the action of the first inclined surface 1513 and the second inclined surface 1613, the installation of the male head 143 on the female head 142 by a worker is facilitated, and cement grout cannot leak out when the male head 143 is removed, so that the grouting efficiency is further improved;
through the arrangement of the rubber pad, when the second fixing column 1410 extends into the mounting groove 1850, the rubber pad is extruded, so that the rubber pad has reverse thrust on the second fixing column 1410, the first protrusion 1511 and the second groove 1412 are respectively fixed more tightly with the second groove 1412 and the first protrusion 1511, the fixing quality of the second fixing column 1410 is further improved, and smooth grouting operation is guaranteed; after slip casting is finished, after staff pull first bar 1240 and second bar 1250, under the effect of the reverse thrust of rubber pad, can make second fixed column 1410 remove from jack 1810 fast, thereby make second fixed column 1410 take out in the short time, thereby make first extrusion piece 1510 and second extrusion piece 1610 can cooperate the realization in the short time again and realize the shutoff to first connecting hole 1310, thereby the outer leakage of cement thick liquid has been avoided, and second fixed column 1410 can take out in shorter time, further improve the efficiency of slip casting operation, thereby can carry out next slip casting operation fast.
In summary, the above-mentioned embodiments are only preferred embodiments of the present invention, and all equivalent changes and modifications made in the claims of the present invention should be covered by the claims of the present invention.
Claims (8)
1. The utility model provides a special slip casting material that is arranged in tunnel area mould slip casting construction which characterized in that: the grouting material is prepared by mixing raw materials with water; the raw materials comprise the following components:
90-150 parts of cement, 20-30 parts of fine aggregate, 26-44 parts of additive, 20-30 parts of high-calcium fly ash, 5-15 parts of calcined shale and 30-35 parts of phosphogypsum; the cement is prepared by mixing 40-70 parts of ordinary Portland cement and 50-80 parts of quick-hardening sulphoaluminate cement.
2. The special grouting material for the grouting construction of the tunnel with the mold as claimed in claim 1, wherein: the additive comprises 10-12 parts of viscosity modifier, 2-8 parts of expanding agent, 5-10 parts of early strength agent, 4-6 parts of water reducing agent and 5-8 parts of water retention agent.
3. The special grouting material for the grouting construction of the tunnel with the mold as claimed in claim 2, wherein: the water retention agent is formed by mixing hydroxyethyl methyl cellulose ether and polyacrylamide.
4. The special grouting material for the grouting construction of the tunnel with the mold as claimed in claim 3, wherein: the mass ratio of the hydroxyethyl methyl cellulose ether to the polyacrylamide is 4: 6.
5. The special grouting material for the grouting construction of the tunnel with the mold as claimed in claim 1, wherein: the fineness modulus of the fine aggregate is 3.5-2.5, and the average particle diameter is 0.65-0.4 mm.
6. The special grouting material for the grouting construction of the tunnel with the mold as claimed in claim 1, wherein: the raw material and water are mixed according to the water-material ratio of 0.18, and the output fluidity is 230-310 mm.
7. The special grouting material for the grouting construction of the tunnel with the mold as claimed in claim 2, wherein: the expanding agent is prepared by adding aluminite, absolute ethyl alcohol, magnesium oxide and silicon resin into a stirrer according to the proportion of 4:2:3:1, and mixing, wherein the average particle size of the expanding agent is 5-12 microns.
8. The application of the special grouting material for the grouting construction of the tunnel strip mold is realized by the special grouting material for the grouting construction of the tunnel strip mold according to any one of claims 1 to 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111479800.2A CN114262203A (en) | 2021-12-06 | 2021-12-06 | Special grouting material for tunnel grouting construction with mold and application thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111479800.2A CN114262203A (en) | 2021-12-06 | 2021-12-06 | Special grouting material for tunnel grouting construction with mold and application thereof |
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| CN114262203A true CN114262203A (en) | 2022-04-01 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113149562A (en) * | 2021-04-22 | 2021-07-23 | 中铁二局第三工程有限公司 | Polymer cement-based high-performance grouting material and preparation method thereof |
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| CN108203281A (en) * | 2018-03-07 | 2018-06-26 | 重庆建工第七建筑工程有限责任公司 | A kind of microdilatancy injecting paste material and preparation method thereof |
| CN108558330A (en) * | 2018-05-22 | 2018-09-21 | 武汉源锦建材科技有限公司 | A kind of tunnel-liner vault band mould grouting microdilatancy grout material |
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2021
- 2021-12-06 CN CN202111479800.2A patent/CN114262203A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108203281A (en) * | 2018-03-07 | 2018-06-26 | 重庆建工第七建筑工程有限责任公司 | A kind of microdilatancy injecting paste material and preparation method thereof |
| CN108558330A (en) * | 2018-05-22 | 2018-09-21 | 武汉源锦建材科技有限公司 | A kind of tunnel-liner vault band mould grouting microdilatancy grout material |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113149562A (en) * | 2021-04-22 | 2021-07-23 | 中铁二局第三工程有限公司 | Polymer cement-based high-performance grouting material and preparation method thereof |
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Application publication date: 20220401 |