CN114427470A - Repairing process for crack between shield segment and ballast bed - Google Patents
Repairing process for crack between shield segment and ballast bed Download PDFInfo
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- CN114427470A CN114427470A CN202011175912.4A CN202011175912A CN114427470A CN 114427470 A CN114427470 A CN 114427470A CN 202011175912 A CN202011175912 A CN 202011175912A CN 114427470 A CN114427470 A CN 114427470A
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- grouting
- crack
- gap
- shield segment
- ballast bed
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- 238000000034 method Methods 0.000 title claims abstract description 10
- 230000008439 repair process Effects 0.000 claims abstract description 17
- 238000005553 drilling Methods 0.000 claims abstract description 13
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 8
- 239000010959 steel Substances 0.000 claims abstract description 8
- 239000000463 material Substances 0.000 claims description 23
- 239000011248 coating agent Substances 0.000 claims description 19
- 238000000576 coating method Methods 0.000 claims description 19
- 238000012544 monitoring process Methods 0.000 claims description 12
- 238000004140 cleaning Methods 0.000 claims description 11
- 230000037452 priming Effects 0.000 claims description 11
- 239000003973 paint Substances 0.000 claims description 9
- 238000007789 sealing Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 5
- 239000002131 composite material Substances 0.000 claims description 5
- 239000011440 grout Substances 0.000 claims description 5
- 229920000642 polymer Polymers 0.000 claims description 5
- 239000002002 slurry Substances 0.000 claims description 5
- 201000010099 disease Diseases 0.000 claims description 4
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 claims description 4
- 239000000428 dust Substances 0.000 claims description 4
- 239000002893 slag Substances 0.000 claims description 4
- 239000000853 adhesive Substances 0.000 claims description 3
- 230000001070 adhesive effect Effects 0.000 claims description 3
- 230000032683 aging Effects 0.000 claims description 3
- 238000005498 polishing Methods 0.000 claims description 3
- 238000010422 painting Methods 0.000 claims description 2
- 238000007599 discharging Methods 0.000 claims 1
- 238000005516 engineering process Methods 0.000 claims 1
- 238000000926 separation method Methods 0.000 description 4
- 239000007788 liquid Substances 0.000 description 3
- 238000007664 blowing Methods 0.000 description 2
- 230000001680 brushing effect Effects 0.000 description 2
- 239000013049 sediment Substances 0.000 description 2
- 241000282414 Homo sapiens Species 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
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Classifications
-
- 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
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
-
- 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
- E21D11/38—Waterproofing; Heat insulating; Soundproofing; Electric insulating
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- Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Lining And Supports For Tunnels (AREA)
Abstract
The invention belongs to the technical field of crack repair, and particularly relates to a repair process of a crack between a shield segment and a ballast bed, which comprises the following steps: the method comprises the steps of determining a longitudinal area of a gap, inserting a steel ruler into the gap area on site, detecting the size of the gap area, recording the position and the size of the gap area, drilling a hole in the middle of a ditch, and drilling a hole in the middle of a side ditch of a ballast bed at an angle of 60 degrees to the ballast bed.
Description
Technical Field
The invention belongs to the technical field of crack repair, and particularly relates to a repair process for a crack between a shield segment and a ballast bed.
Background
The tunnel is an engineering building buried in the ground and is a form of utilizing underground space by human beings, and the tunnel can be divided into a traffic tunnel, a hydraulic tunnel, a municipal tunnel and the like, and the structure of the tunnel comprises a main building and an accessory device. The main building comprises a tunnel body and a tunnel door, the auxiliary equipment comprises a car-avoiding tunnel, fire-fighting equipment, emergency communication and water-proof and drainage equipment, the long tunnel is also provided with special ventilation and lighting equipment, the tunnel segment is laid on the inner wall of the tunnel in the current subway tunnel, and then a track bed for bearing the track is arranged at the bottom of the tunnel.
There is not any connected mode in the design between shield segment track concrete ballast bed and the shield section of jurisdiction, the expansion joint position that sets up between two adjacent ballast beds is more weak, this position is at first peeled off the phenomenon to appear, if there is water between the separation seam layer, when the train passes through, become to be close vacuum environment in the twinkling of an eye between ballast bed and the shield pipe wall, and simultaneously, the inside high pressure flowing water that produces in space between the layer is washed away repeatedly the weak department and is patted, make two concrete layer contact surface intensity decay, the wearing and tearing aggravation, if untimely improvement, it forms the thick liquid to develop to grout outflow, vertical separation appears in tunnel section of jurisdiction and near the joint part of ballast bed expansion joint, the length of separation is concentrated in the vertical 1 ~ 2m scope in ballast bed expansion joint both sides.
Disclosure of Invention
To solve the problems set forth in the background art described above. The invention provides a repair process of a crack between a shield segment and a ballast bed, and aims to solve the problems.
In order to achieve the purpose, the invention provides the following technical scheme: a repair process for a crack between a shield segment and a ballast bed comprises the following steps:
step S1, determining a longitudinal region of the gap, inserting a straight steel ruler into the gap region on site, detecting the size of the gap region, and then recording the position and the size of the gap region;
step S2, drilling a middle part of the ditch, namely drilling a hole in the middle part of the side ditch of the ballast bed at an angle of 60 degrees inclined to the ballast bed, wherein the hole penetrates through the bottom of the side ditch of the ballast bed and the surface of the side wall of the tunnel but does not extend into the ballast bed;
step S3, cleaning holes, wherein the grouting holes are blown dry and discharged with high-pressure air, and the arrangement of the grouting holes is carried out according to the field condition and the air intake and discharge, and the grouting and discharge are carried out to distribute the holes;
s4, arranging elevation monitoring points of the track bed, arranging level points on the edge of the track bed, and recording initial readings; monitoring observation points and corresponding files for shield segment settlement and ballast bed deformation in the quality guarantee period are established;
step S5, grouting, namely grouting the grouting holes by using a grouting machine, controlling the pressure within 2MPa, and stopping grouting until grout is discharged from the side ditch edge of the ballast bed and the parting joint of the shield pipe wall;
step S6, cleaning a grouting part, removing redundant gap materials after the repair materials are solidified, and polishing the surface of the gap to be flat;
and S6, plugging the grouting holes, coating a layer of priming paint along the surface of the crack, after the surface of the priming paint is dried, coating the surface sealing coating material for more than 3 times, wherein the two coating directions are mutually vertical.
Preferably, in the step S6, the width of the priming material is 10cm, the thickness of the priming material is 0.2mm, and the surface sealing coating material is coated for more than 3 times, so that the thickness of the coating reaches 0.5 mm.
Preferably, in step S6, before brushing, the surface of the crack needs to be dedusted and brushed, and both sides of the surface of the crack are brushed by a steel wire brush and dedusted by air blowing.
Preferably, the diameter of the drilled hole in the step S2 is 16mm, and the distance between two adjacent 4 is 50 cm.
Preferably, the elevation of the leveling point is monitored every 5min during the step S5, and when the elevation difference is increased by 2mm, the grouting is stopped immediately.
Preferably, before the step S5, a flexible waterproof material is additionally used for the inner edge of the drainage side ditch formed between the track bed 2 and the shield segment, so as to prevent the track bed side ditch 3 from seeping water and entering the bottom of the track bed 2 to form a new disease.
Preferably, the grouting material adopted in step S5 is a guoxing-brand concrete polymer inorganic composite repairing agent: the fluidity is good, the setting time is fast, the early strength is high and can reach more than 20Mpa for 2 hours, and the strength can reach more than 60Mpa for 28 days; strong adhesive force, weather resistance, strong aging resistance and micro-expansion function.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, aiming at the gap between the track bed and the side wall of the tunnel, the process sequence of drilling a longitudinal region of the gap, drilling a middle part of a side ditch of the track bed, cleaning holes, arranging track bed elevation monitoring points, grouting, cleaning a grouting part and plugging the grouting holes is determined, the gap is filled and repaired, a proper repairing material is used, the repairing work is completed in the skylight period of vehicle operation, the whole repairing process is simple and quick, the time limit of the skylight period can be adapted, the problem of the gap between the track bed and the side wall of the tunnel is solved, and the safe and stable operation of the vehicle is ensured.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic cross-sectional view of the present invention;
fig. 3 is an enlarged schematic view of a portion a in fig. 2.
In the figure: 1. a tunnel sidewall; 2. a ballast bed; 3. side ditches of the ballast bed; 4. grouting holes; 5. and (7) seam separation.
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.
Referring to fig. 1-3, the present invention provides the following technical solutions: a repair process for a crack between a shield segment and a ballast bed comprises the following steps:
step S1, determining a longitudinal area of the gap 5, inserting a straight steel ruler into the gap 5 area on site, detecting the size of the gap 5 area, and then recording the position and the size of the gap 5 area;
step S2, drilling a middle part of the ditch, namely drilling a hole in the middle part of the track bed side ditch 3 at an angle of 260 degrees to the track bed, wherein the hole penetrates through the bottom of the track bed side ditch 3 and the surface of the side wall 1 of the tunnel but does not extend into the track bed 2;
step S3, cleaning holes, wherein the grouting holes 4 are dried by high-pressure air to remove slag, and the arrangement of the grouting holes 4 is to arrange the holes according to the field condition and the air intake to remove slag, and the slurry is fed into the grouting holes to discharge slurry;
s4, arranging elevation monitoring points of the track bed, arranging level points on the edge of the track bed 2, and recording initial readings; monitoring observation points and corresponding files for shield segment settlement and ballast bed 2 deformation in the quality guarantee period are established;
step S5, grouting, namely grouting the grouting holes 4 by using a grouting machine, controlling the pressure within 2MPa, and stopping grouting until grout is discharged from the edge of the side ditch 3 of the ballast bed and the parting position of the wall of the shield pipe;
step S6, cleaning a grouting part, removing redundant gap materials after the repair materials are solidified, and polishing the surface of the gap to be flat;
and S6, plugging the grouting holes, coating a layer of priming paint along the surface of the crack, after the surface of the priming paint is dried, coating the surface sealing coating material for more than 3 times, wherein the two coating directions are mutually vertical.
In the embodiment, the invention aims at the gap between the ballast bed 2 and the tunnel side wall 1, the process sequence of the longitudinal area of the gap 5, the middle drilling of the ballast bed side ditch 3, hole cleaning, arrangement of the height monitoring points of the ballast bed 2, grouting part cleaning and grouting hole 4 plugging is determined, the gap is filled and repaired, a proper repairing material is used, the repairing work is completed in the skylight period of vehicle operation, the whole repairing process is simple and quick, the time limit of the skylight period can be adapted, the problem of the gap between the ballast bed 2 and the tunnel side wall 1 is solved, the operation safety and stability of the vehicle are ensured, and when the crack between the ballast bed 2 and the shield segment is repaired, the condition that the crack exists in the ballast bed 2 is repaired in time: cleaning the groove, grouting, and painting and repairing with the Guoxing brand concrete polymer inorganic composite repairing agent.
Specifically, in the step S6, the width of the priming paint is 10cm, the thickness of the priming paint is 0.2mm, and the surface sealing coating material is coated for more than 3 times, so that the thickness of the coating reaches 0.5mm, and the coating has a good protection effect.
Specifically, in step S6, before brushing, dust and bristle are removed from the crack surface, and a steel wire brush is used to brush bristles on both sides of the crack surface, and air is used to remove dust, so as to enhance the adhesion degree with the slurry.
Specifically, the diameter of the drilled hole in step S2 is 16mm, and the distance between two adjacent holes 4 is 50 cm.
Specifically, in the step S5, elevation monitoring is performed on the leveling point every 5min, and when the elevation difference increases by 2mm, grouting is immediately stopped.
Specifically, before step S5, a flexible waterproof material is additionally used for the inner edge of the gutter formed between the track bed 2 and the shield segment, so as to prevent the water seeping from the track bed side ditch 3 from entering the bottom of the track bed 2 to form new diseases.
Specifically, the grouting material adopted in step S5 is a guoxing-brand concrete polymer inorganic composite repairing agent: the fluidity is good, the setting time is fast, the early strength is high and can reach more than 20Mpa for 2 hours, and the strength can reach more than 60Mpa for 28 days; the adhesive force is strong, the weather resistance and the aging resistance are strong, the micro-expansion function is realized, and the detection results of the national prosperous concrete polymer inorganic composite repairing agent are as follows:
the working principle and the using process of the invention are as follows: on-spot steel ruler that adopts inserts 5 regions of separating joint, adopt diameter 16mm drilling, 3 bottom shield tunnel segment surfaces of oblique track bed side ditch 2 slope 60 cross track bed side ditch are bored at 3 middle parts of track bed side ditch, do not stretch into track bed 2, the sediment is arranged to using highly-compressed air blowing dry in the drilling of grout, arranging of grouting hole 4 should arrange the sediment according to the site conditions and admitting air, advance thick liquid and arrange the thick liquid etc. and arrange the hole, 2 border arrangement levelling points at track bed, and record initial reading: and establishing an observation point and corresponding files for monitoring the shield segment settlement and the track bed 2 deformation in the quality guarantee period, wherein the observation point and the corresponding files are used for grouting a grouting hole 4 by a grouting machine, the pressure is controlled within 2MPa, the grouting is stopped until slurry is discharged from the edge of a track bed side ditch 3 and a shield tube wall gap, the elevation monitoring is carried out on a leveling point every 5min in the grouting process, the grouting is stopped immediately when the elevation difference is increased by 2mm, and technical measures of adopting flexible waterproof materials are added to the inner edge of the track bed side ditch 3 formed between the track bed 2 and the shield segment so as to prevent the water seepage of the ditch from entering the bottom of the track bed 2 which is not found to form a new disease.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. The utility model provides a repair technology of crack between shield constructs section of jurisdiction and ballast bed which characterized in that: the method comprises the following steps:
step S1, determining a longitudinal area of the gap (5), inserting a straight steel ruler into the gap (5) area on site, detecting the size of the gap (5) area, and then recording the position and the size of the gap (5) area;
step S2, drilling a middle part of the ditch, namely drilling a hole in the middle part of the track bed side ditch (3) at an angle of 60 degrees inclined to the track bed (2), wherein the hole penetrates through the bottom of the track bed side ditch (3) and the surface of the side wall (1) of the tunnel but does not extend into the track bed (2);
step S3, cleaning holes, wherein the grouting holes (4) are blown dry by high-pressure air to remove slag, the arrangement of the grouting holes (4) is to arrange the holes according to the field condition and the air intake to remove slag, and the grouting and the slurry discharging are carried out to distribute the holes;
s4, arranging elevation monitoring points of the track bed, arranging level points on the edge of the track bed (2), and recording initial readings; and establishing monitoring observation points and corresponding files for shield segment settlement and ballast bed (2) deformation in the quality guarantee period;
step S5, grouting, namely grouting the grouting holes (4) by using a grouting machine, controlling the pressure within 2MPa, and stopping grouting until grout is discharged from the edge of the ballast side ditch (3) and the parting position of the shield pipe wall;
step S6, cleaning a grouting part, removing redundant gap materials after the repair materials are solidified, and polishing the surface of the gap to be flat;
and S6, plugging the grouting holes, coating a layer of priming paint along the surface of the crack, after the surface of the priming paint is dried, coating the surface sealing coating material for more than 3 times, wherein the two coating directions are mutually vertical.
2. The repair process of the crack between the shield segment and the ballast bed according to claim 1, characterized in that: in the step S6, the width of the priming paint is 10cm, the thickness is 0.2mm, and the surface sealing coating material is coated more than 3 times to make the thickness of the coating reach 0.5 mm.
3. The repair process of the crack between the shield segment and the ballast bed according to claim 1, characterized in that: in the step S6, before painting, dust and bristle are removed from the crack surface, and a steel wire brush is used to brush bristles on two sides of the crack surface, and air is used to remove dust.
4. The repair process of the crack between the shield segment and the ballast bed according to claim 1, characterized in that: the diameter of the drilled hole in the step S2 is 16mm, and the distance between two adjacent holes (4) is 50 cm.
5. The repair process of the crack between the shield segment and the ballast bed according to claim 1, characterized in that: and in the step S5, monitoring the elevation of the leveling point every 5min, and stopping grouting immediately when the elevation difference is increased by 2 mm.
6. The repair process of the crack between the shield segment and the ballast bed according to claim 1, characterized in that: before step S5, flexible waterproof materials are additionally adopted for the inner edge of a drainage side ditch formed between the track bed (2) and the shield segment together, so that the phenomenon that the side ditch (3) of the track bed seeps water and enters the bottom of the track bed (2) to form a new disease is avoided.
7. The repair process of the crack between the shield segment and the ballast bed according to claim 1, characterized in that: the grouting material adopted in the step S5 is a Guoxing brand concrete polymer inorganic composite repairing agent: the fluidity is good, the setting time is fast, the early strength is high and can reach more than 20Mpa for 2 hours, and the strength can reach more than 60Mpa for 28 days; strong adhesive force, weather resistance, strong aging resistance and micro-expansion function.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011175912.4A CN114427470A (en) | 2020-10-29 | 2020-10-29 | Repairing process for crack between shield segment and ballast bed |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011175912.4A CN114427470A (en) | 2020-10-29 | 2020-10-29 | Repairing process for crack between shield segment and ballast bed |
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| Publication Number | Publication Date |
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| CN114427470A true CN114427470A (en) | 2022-05-03 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011175912.4A Pending CN114427470A (en) | 2020-10-29 | 2020-10-29 | Repairing process for crack between shield segment and ballast bed |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114593989A (en) * | 2022-05-10 | 2022-06-07 | 西南交通大学 | Ballastless track cohesion parameter assembly type measuring device and measuring method thereof |
-
2020
- 2020-10-29 CN CN202011175912.4A patent/CN114427470A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114593989A (en) * | 2022-05-10 | 2022-06-07 | 西南交通大学 | Ballastless track cohesion parameter assembly type measuring device and measuring method thereof |
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