CN118257604A - Large-scale pile group construction method for shield cutting and grinding - Google Patents
Large-scale pile group construction method for shield cutting and grinding Download PDFInfo
- Publication number
- CN118257604A CN118257604A CN202410691192.9A CN202410691192A CN118257604A CN 118257604 A CN118257604 A CN 118257604A CN 202410691192 A CN202410691192 A CN 202410691192A CN 118257604 A CN118257604 A CN 118257604A
- Authority
- CN
- China
- Prior art keywords
- shield
- pile
- pressure
- grouting
- grinding
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000010276 construction Methods 0.000 title claims abstract description 54
- 238000005520 cutting process Methods 0.000 title claims abstract description 33
- 230000005641 tunneling Effects 0.000 claims abstract description 25
- 239000002893 slag Substances 0.000 claims abstract description 13
- 238000001514 detection method Methods 0.000 claims abstract description 12
- 239000002002 slurry Substances 0.000 claims abstract description 9
- 238000004140 cleaning Methods 0.000 claims abstract description 7
- 238000012544 monitoring process Methods 0.000 claims abstract description 7
- 229910001294 Reinforcing steel Inorganic materials 0.000 claims abstract description 5
- 238000011835 investigation Methods 0.000 claims abstract description 4
- 238000012545 processing Methods 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 36
- 239000002689 soil Substances 0.000 claims description 22
- 230000008569 process Effects 0.000 claims description 14
- 230000001360 synchronised effect Effects 0.000 claims description 11
- 229910000831 Steel Inorganic materials 0.000 claims description 8
- 239000010959 steel Substances 0.000 claims description 8
- 238000009412 basement excavation Methods 0.000 claims description 6
- 238000002347 injection Methods 0.000 claims description 6
- 239000007924 injection Substances 0.000 claims description 6
- 238000007689 inspection Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 230000008859 change Effects 0.000 claims description 4
- 230000000694 effects Effects 0.000 claims description 4
- 230000000903 blocking effect Effects 0.000 claims description 3
- 238000012937 correction Methods 0.000 claims description 3
- 238000013461 design Methods 0.000 claims description 3
- 238000007599 discharging Methods 0.000 claims description 3
- 238000007667 floating Methods 0.000 claims description 3
- 239000003673 groundwater Substances 0.000 claims description 3
- 210000001624 hip Anatomy 0.000 claims description 3
- 238000005259 measurement Methods 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 238000010008 shearing Methods 0.000 claims description 3
- 230000000087 stabilizing effect Effects 0.000 claims description 3
- 238000012795 verification Methods 0.000 claims description 3
- 239000002023 wood Substances 0.000 claims description 3
- 239000004567 concrete Substances 0.000 description 8
- 230000008901 benefit Effects 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000004568 cement Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000003475 lamination Methods 0.000 description 2
- 239000011150 reinforced concrete Substances 0.000 description 2
- 230000002787 reinforcement Effects 0.000 description 2
- 230000003014 reinforcing effect Effects 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Excavating Of Shafts Or Tunnels (AREA)
Abstract
The application relates to a large-scale pile group construction method for shield cutting and grinding, which comprises the following steps: s1, pile foundation investigation and treatment; s2, evaluating the adaptability of the shield machine to the pile grinding; s3, pile grinding and tunneling of a shield machine; s4, selecting a shutdown position of the shield machine, and selecting a region shutdown without pipelines or buildings when slag is difficult to remove or slag is impossible to remove by the screw machine, wherein the region shutdown is convenient for ground region observation and settlement monitoring, and the stratum has good self-stability and air tightness; s5, stopping, checking and processing, performing waterproof and tunnel face stability construction, and cleaning dregs and reinforcing steel bars to a cutter head panel; s6, restoring tunneling, and starting the shield machine to continue tunneling after the cutterhead is cleaned. The application actively cuts piles by the shield machine, does not need to coordinate the ground surrounding and pile pulling equipment entering pile foundation treatment, and sequentially carries out measures such as slag discharge replacement, slurry gas replacement, airtight detection and the like after shutdown, thereby effectively ensuring long-distance and large-area pile cutting and grinding group pile operation with high quality and high safety in a muddy stratum.
Description
Technical Field
The application relates to the technical field of foundation construction, in particular to a large-scale pile group construction method for shield cutting and grinding.
Background
The shield method has the advantages of safety, rapidness, small stratum settlement, high mechanization degree and the like, and is widely applied to construction of urban subway tunnels, railway tunnels, highway tunnels, common ditches and the like.
When constructing a shield tunnel in a central area of a city, the situation of existing building pile foundations is encountered. When the line is limited and the pile foundation can not be avoided, the barrier pile is generally removed in advance by adopting the traditional modes of removing the original structure, pulling the pile on the ground, excavating the pile after excavating the vertical shaft, and the like, and the modes are relatively safe and mature, but have the defects of large influence on the surrounding environment, high cost, long construction period, and the like.
Therefore, the research of a feasible method for cutting and grinding large-scale reinforced concrete pile groups in long distance and large area by a silt stratum shield is significant.
Disclosure of Invention
The application provides a large-scale pile group construction method for shield cutting and grinding, which is used for directly cutting and grinding large-scale reinforced concrete pile groups in long distance and large area in a silt stratum by a shield machine.
The application provides a large-scale pile group construction method for shield cutting and grinding, which adopts the following technical scheme:
A shield cutting and grinding large-scale pile group construction method comprises the following steps:
s1, pile foundation investigation and treatment, wherein the number of pile foundations, the hardness of the pile foundations and the size of steel bars are determined according to geophysical prospecting data and on-site excavation conditions, and the configuration of a cutter head, a screw conveyer and a hydraulic motor of a shield machine is designed in a targeted manner.
S2, evaluating the adaptability of the shield machine to the pile grinding, arranging a cutter disc according to the conventional shield tunneling construction configuration, and configuring the cutter disc of the shield machine in a targeted manner after pile group is found;
S3, performing pile grinding and tunneling by the shield machine, wherein the pile grinding and tunneling thrust of the shield machine is controlled to be 9000 KN-12000 KN, and the tunneling speed is controlled to be 5-10 mm/min;
s4, selecting a shutdown position of the shield machine, and selecting a region shutdown without pipelines or buildings when slag is difficult to remove or slag is impossible to remove by the screw machine, wherein the region shutdown is convenient for ground region observation and settlement monitoring, and the stratum has good self-stability and air tightness;
s5, stopping, checking and processing, performing waterproof and tunnel face stability construction, and cleaning dregs and reinforcing steel bars to a cutter head panel;
s6, restoring tunneling, and starting the shield machine to continue tunneling after the cutterhead is cleaned.
Still further, the step S5 includes:
S51, performing construction by a water stop ring at the rear of the shield tail, wherein the water stop ring is selected as a3 rd-5 th ring at the rear of the shield tail according to the site situation, and injecting double-liquid slurry into a third full ring at the rear of the shield tail, wherein the grouting pressure is controlled to be 3.5bar, and each hole is injected with 0.8-1.5 cubic meters;
s52, injecting balance shield mud and deslagging replacement, wherein a synchronous grouting system is adopted, the balance ball valve of the soil bin wall is used for multipoint injection, the pressure of the soil bin is controlled to be 1.5bar, a screw machine is used for deslagging, the pressure fluctuation range is controlled to be 0.2bar, and a cutter head is slowly rotated in the injection process;
S53, grading pressurization and three-stage pressurization are carried out on the shield mud, wherein the front two stages are dynamically stabilized for 2 hours, and the last stage is stabilized for 6 hours to ensure that the position of the tunnel face of the shield mud material forms a mud wall;
S54, slurry gas replacement, step-down is carried out in a 1.6-1.8bar interval, 0.2bar is used as a first stage, natural depressurization is adopted, and pressure release time is closely observed and recorded.
Further, the three-stage pressurizing pressure in the step S53 is 1.2-1.4bar, 1.4-1.6bar and 1.6-1.8bar, during the second stage pressurizing process, the shield body retreats by 80-100mm, the cutterhead is slowly rotated for 2-3 times, the rotating speed is 0.1-0.5rpm, and the cutterhead is not rotated as much as possible during the last stage pressurizing.
Further, in the step S54, if the pressure stabilizing time of the depressurization exceeds 6 hours, the step depressurization is performed by gas pressure maintaining, the air release amount of the air compressor is ensured to be not more than 10% within the pressure maintaining time range of each step, and the pressure is reduced by a soil discharging mode of the screw machine until the pressure is reduced to the set working pressure.
Still further, the step S5 further includes:
S55, airtight detection, namely, boosting the pressure from 0 to a design value for no more than 10 minutes, then keeping the air pressure to 1.6-1.8 bar, checking the air leakage phenomenon at the tail of a ground shield and the like if the air pressure is stable for more than 2 hours and no obvious change exists, simultaneously focusing on the air supply condition of an air compressor, keeping the working pressure of a soil bin at 1.7-1.8 bar, keeping the fluctuation value of the air pressure in the bin at no more than 0.05bar, and keeping the air supply amount for 2 hours less than 10% of the air supply capacity, so that the mud film is manufactured to meet the requirements;
if the airtight detection is not qualified, repeating steps S52 to S55.
Still further, the step S5 further includes:
S56, first bin opening inspection, first soil bin entering inspection, tunnel face geology and cutter head opening condition, mud film effect verification, tunnel face dew-out condition and stratum sampling, and template blocking of the cutter head opening position, wherein a back square wood is supported on the inner wall of the soil bin, and the tunnel face stability is judged by combining the factors;
If it is determined that the tunnel face is unstable, the steps S52 to S56 are repeated.
Furthermore, in the tunneling process of the shield machine, the attitude deviation correction amount of each ring of shield machine is controlled within 4 mm; the synchronous grouting quantity and the propelling stroke are in a direct proportion relation, and the grouting pressure is not more than 0.4MPa.
Further, in the step S5, if the opening of the cutterhead is blocked by dregs, cleaning is performed by using a pick and a spade until reaching the cutterhead panel; if the cutter head opening or the cutter is wound with the steel bar, the hydraulic steel bar shear is used for shearing.
Further, in the step S52, wall hole grouting starts from two waists of the tunnel, the top is injected, the bottom is injected again, and the grouting hole is closed after grouting; when in synchronous grouting, each grouting pipe is simultaneously performed, and the grouting pressure of the two grouting pipes at the lower side is properly increased.
Further, in the step S52, the grouting process should be selected to perform synchronous grouting and secondary grouting after the wall according to the control requirements of the engineering to the tunnel deformation and the stratum settlement, and the secondary grouting after the wall should be performed in time in cooperation with ground monitoring and in-hole rechecking measurement after the lining segment is separated from the shield tail in order to cope with the floating of the segment in the region where the groundwater is abundant, so as to fill the gap between the segment and the ground.
In summary, the beneficial technical effects of the application are as follows:
1. The active pile cutting of the shield machine solves the construction difficulty of the existing building pile encountered by the shield, especially the construction condition of on-site pile foundation-free pulling out; the method does not need to coordinate the ground surrounding and pile pulling equipment entering pile foundation treatment, effectively saves high pile pulling construction cost, reduces the construction cost of the engineering, and has little influence on surrounding construction environment; the complex procedures of ground coordination, pile head detection, pile pulling and the like are avoided, the construction period is shortened to a great extent, and the investment of engineering manpower, materials and machinery is reduced;
2. The method solves the problems of the existing building piles in shield construction, directly reduces the emission of CO 2 without pile pulling equipment operation, and tramples the green low-carbon construction concept; the disposal of pile pulling slag soil is reduced, the positive influence on the whole ecological environment, which cannot be estimated, is brought, and the environmental protection benefit is obvious;
3. After stopping, slag discharge replacement, slurry gas replacement, airtight detection and other measures are sequentially carried out, so that long-distance and large-area pile cutting and grinding operation with high quality and high safety in a silt stratum can be effectively ensured.
Drawings
FIG. 1 is a flow chart of a construction method according to an embodiment of the present application;
Fig. 2 is a schematic flow chart of step S5 in the embodiment of the present application.
Detailed Description
The following description of the embodiments of the present application will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the application are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
The embodiment of the application discloses a large-scale pile group construction method for shield cutting and grinding. Referring to fig. 1 and 2, a method for constructing a large-scale pile group by shield cutting and grinding includes the following steps:
S1, pile foundation investigation and treatment, wherein the number of pile foundations, the hardness of the pile foundations and the size of reinforcing steel bars are determined according to geophysical prospecting data and on-site excavation conditions, the outer diameters of main reinforcements, reinforcing stirrups and spiral stirrups on the pile foundations and the rebound strength of core samples of the pile foundations are required to be specific, the range of the pile foundations which invade a tunnel is required to be known, and the cutter head, the spiral conveyor and the hydraulic motor of the shield machine are designed in a targeted mode according to interval stratum and pile grinding construction requirements.
S2, evaluating the adaptability of the shield machine to the pile grinding, selecting a soil pressure balance shield machine, firstly setting a cutter head according to the conventional shield tunneling construction configuration, and configuring the cutter head of the shield machine in a targeted manner after pile group is found.
For example, in one construction example, the main reinforcement and the reinforcing stirrup of the pile foundation are detected to be 12mm, the spiral stirrup is 6mm, the rebound strength of the core sample of the pile foundation is 28MPa, and the range of the pile foundation group invaded a left-line tunnel is about 185, and the range of the right-line tunnel is about 127.
When the shield tunneling machine cutterhead is configured, an iron construction reworking ZTE6410 cutterhead is adopted, the cutterhead excavation diameter is 6410mm, the cutterhead opening ratio is about 50%, a fishtail center cutter 1 handle, an arc concrete cutting tearing cutter 16 handle, a flat bottom concrete cutting tearing cutter 12 handle, a flat bottom concrete cutting tearing cutter 6 handle, a cutter 56 handle, a side cutter (left) 6 handle, a side cutter (right) 6 handle, a transverse gauge cutter 6 handle and an overexcavation cutter 1 handle are arranged.
After pile group is found, the cutter head of the shield machine is configured in a targeted manner, the cutter head of the left line shield machine is provided with a cutter head with the excavation diameter of 6480mm and the cutter head opening rate of about 40%, and the cutter head is provided with a center concrete cutting cutter 4 handle, an installation concrete cutting cutter 32 handle, a welding concrete cutting cutter 38 handle, a scraper 60 handle and an overexcavation cutter 1 handle. The right line shield machine is provided with a cutter head with the excavation diameter of 6470mm, the cutter head opening ratio of about 40 percent, a center cutter 4 handle, a front-mounted concrete cutting tearing cutter 32 handle, a welding concrete cutting tearing cutter (H160) 23 handle, a front cutter 36 handle, a side cutter (left) 4 handle, a side cutter (right) 4 handle, a gage cutter 12 handle and an overexcavation cutter 1 handle.
S3, performing pile grinding and tunneling by the shield machine, wherein the pile grinding and tunneling thrust of the shield machine is controlled to 9000 KN-12000 KN, the tunneling speed is controlled to 5-10 mm/min, and the posture deviation correction amount of each ring of shield machine is controlled to be within 4 mm; the synchronous grouting quantity and the propelling stroke are in a direct proportion relation, and the grouting pressure is not more than 0.4MPa.
S4, selecting a shutdown position of the shield machine, and selecting a pipeline-free building, which has good stratum self-stability and air tightness when the screw machine is found to be difficult to slag or incapable of slag in the tunneling process, and shutting down the shield machine in a region which is convenient for ground surface region observation and settlement monitoring.
S5, stopping, checking and processing, performing waterproof and tunnel face stability construction, and cleaning dregs and reinforcing steel bars to the cutter head panel.
S6, restoring tunneling, and starting the shield machine to continue tunneling after the cutterhead is cleaned.
Referring to fig. 2, step S5 includes:
S51, performing water stop ring construction at the rear of the shield tail, wherein the water stop ring is selected as a3 rd-5 th ring at the rear of the shield tail according to the site condition, and double-liquid slurry is injected into a third full ring at the rear of the shield tail, wherein the water-cement ratio of A liquid to water-cement ratio is 1:1, liquid water glass 38 Baume degree B, A: b=6:1, the grouting pressure is controlled to be 3.5bar, and each hole is injected with 0.8-1.5 cubic meters.
S52, injecting the balance shield mud and carrying out deslagging replacement, wherein a synchronous grouting system is adopted, the soil bin wall balance ball valve is used for multipoint injection, the soil bin pressure is controlled to be 1.5bar, a screw machine is used for deslagging, the pressure fluctuation range is controlled to be 0.2bar, and a cutter head is slowly rotated in the injection process.
S53, grading pressurization and three-stage pressurization are carried out on the shield mud, wherein the front two stages are dynamically stabilized for 2 hours, and the last stage is stabilized for 6 hours to ensure that the position of the tunnel face of the shield mud material forms a mud wall; and the three-stage pressurizing pressure is 1.2-1.4bar, 1.4-1.6bar and 1.6-1.8bar, in the second stage pressurizing process, the shield body retreats by 80-100mm, the cutterhead is slowly rotated for 2-3 times, the rotating speed is 0.1-0.5rpm, and the cutterhead is not rotated as much as possible in the final stage pressurizing process.
S54, slurry gas replacement, step-down is carried out in a 1.6-1.8bar interval, 0.2bar is used as a first stage, natural depressurization is adopted, and pressure release time is closely observed and recorded; if the pressure stabilizing time of the depressurization exceeds 6 hours, the staged depressurization adopts gas pressure maintaining, the air leakage amount of the air compressor is ensured not to be more than 10% in the pressure maintaining time range of each stage, and the depressurization is carried out in a soil discharging mode of the spiral machine until the pressure is reduced to the set working pressure.
And, step S5 further includes:
S55, airtight detection, namely, raising the pressure from 0 to a design value and not exceeding 10min, then keeping the air pressure to 1.6-1.8 bar, checking the air leakage phenomenon at the tail of a ground shield and the like if the air pressure is stable for more than 2h and has no obvious change, simultaneously focusing on the air supply condition of an air compressor, keeping the working pressure of a soil bin to 1.7bar-1.8bar, keeping the air pressure fluctuation value in the bin to not more than 0.05bar, keeping the air supply amount to be less than 10% of the air supply capacity for 2h, and making a mud film to meet the requirement, so that the air tightness can be judged to be qualified;
if the airtight detection is not qualified, repeating steps S52 to S55.
S56, first bin opening inspection, first soil bin entering inspection, tunnel face geology and cutter head opening condition, mud film effect verification, tunnel face dew-out condition and stratum sampling, and template blocking of the cutter head opening position, wherein a back square wood is supported on the inner wall of the soil bin, and the tunnel face stability is judged by combining the factors;
If it is determined that the tunnel face is unstable, the steps S52 to S56 are repeated.
In addition, in step S5, if the opening of the cutterhead is blocked by dregs, cleaning is carried out by using a pick and a spade until reaching the cutterhead panel; if the cutter head opening or the cutter is winded with the steel bar, the manual hydraulic steel bar scissors DXsc-25 are used for shearing. In step S52, according to the soil layer traversed by the shield, taking into account filling coefficients of grouting amount, grouting wall holes from two waists of the tunnel, and grouting the top and the bottom after grouting, and sealing grouting holes after grouting; when grouting is performed synchronously, grouting pipes are simultaneously performed, grouting pressure of two grouting pipes at the lower side is properly increased, the purposes of waterproof tunnel structures and ground settlement are achieved, and the grouting machine pressure is based on the principle of controlling ground surface deformation, so that the pressure is uniform so as not to damage the pipe pieces.
In addition, in step S52, the grouting process is performed outside the segment, and synchronous grouting and secondary grouting after the wall should be selected according to the control requirements of the constructed engineering on tunnel deformation and stratum settlement, and in order to cope with the floating of the segment in the region with abundant groundwater, secondary grouting after the wall should be performed in time in cooperation with ground monitoring and in-hole rechecking measurement after the lining segment is separated from the tail of the shield, and the gap between the segment and the ground is filled.
In an engineering example, for example, a 04-segment shield section is constructed by a track traffic No. 4 line worker Cheng Tujian in a certain city, and a stratum traversed by a section tunnel is sequentially formed by an artificial earth filling layer, a fourth system new system flood lamination layer and a fourth system update system flood lamination layer from top to bottom. Compared with the traditional method, the technology of directly cutting and grinding large-scale pile foundation groups in a long-distance and large-area manner by adopting the shield, avoids a series of complicated procedures such as ground coordination, pile head detection, pile pulling and the like, completely overturns the traditional method for solving the problem that the shield passes through pile groups, does not need pile pulling, and shortens the construction period. Meanwhile, because the ground surrounding and pile pulling equipment approach pile foundation treatment is not required to be coordinated, the influence on the surrounding construction environment is small, the pile pulling period, the high pile pulling construction cost and the like are effectively saved, and the social and economic benefits are remarkable.
Therefore, the method is adopted to actively cut the pile of the shield machine, solves the construction difficulty of the existing building pile of the shield, and particularly solves the construction condition of on-site pile foundation-free pulling-out. The method does not need to coordinate the ground surrounding and pile pulling equipment entering pile foundation treatment, effectively saves high pile pulling construction cost, reduces the construction cost of the engineering, and has little influence on surrounding construction environment; and a series of complicated procedures such as ground coordination, pile head detection and digging, pile pulling and the like are avoided, the construction period is shortened to a great extent, and the investment of engineering manpower, materials and machinery is reduced.
By adopting the construction method, the problems of the existing building piles in shield construction are solved, the reduction of the emission of CO 2 is directly realized without pile pulling equipment operation, and the green low-carbon construction concept is practiced; and the disposal of pile pulling slag soil is reduced, the positive influence which cannot be estimated is brought to the whole ecological environment, and the environmental protection benefit is obvious.
The method directly carries out the active pile cutting operation of the shield machine without pile pulling, is particularly suitable for the conditions of large traffic flow in main urban areas and no surrounding pile pulling on the ground, and hardly has any influence on the life of citizens. The construction method can safely and effectively solve the problem that the shield encounters the existing building pile, and provides a construction reference basis for the subsequent engineering.
And the measures such as slag discharge replacement, slurry gas replacement, airtight detection and the like are sequentially carried out after the machine is stopped, so that the long-distance and large-area pile cutting and grinding operation with high quality and high safety in a silt stratum can be effectively ensured.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs. The terms "first," "second," "third," and the like in the description and in the claims, are not used for any order, quantity, or importance, but are used for distinguishing between different elements. The terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, is intended to mean that elements or items that are present in front of "comprising" or "comprising" are included in the word "comprising" or "comprising", and equivalents thereof, without excluding other elements or items. "upper", "lower", "left", "right", etc. are used merely to denote relative positional relationships, which may also change accordingly when the absolute position of the object to be described changes.
The above embodiments are not intended to limit the scope of the present application, so: all equivalent changes in structure, shape and principle of the application should be covered in the scope of protection of the application.
Claims (10)
1. The large-scale pile group construction method for shield cutting and grinding is characterized by comprising the following steps of:
s1, pile foundation investigation and treatment, namely determining the number of pile foundations, the hardness of the pile foundations and the size of steel bars according to geophysical prospecting data and on-site excavation conditions, and designing the configuration of a cutter head, a screw conveyor and a hydraulic motor of a shield machine in a targeted manner;
S2, evaluating the adaptability of the shield machine to the pile grinding, arranging a cutter disc according to the conventional shield tunneling construction configuration, and configuring the cutter disc of the shield machine in a targeted manner after pile group is found;
S3, performing pile grinding and tunneling by the shield machine, wherein the pile grinding and tunneling thrust of the shield machine is controlled to be 9000 KN-12000 KN, and the tunneling speed is controlled to be 5-10 mm/min;
s4, selecting a shutdown position of the shield machine, and selecting a region shutdown without pipelines or buildings when slag is difficult to remove or slag is impossible to remove by the screw machine, wherein the region shutdown is convenient for ground region observation and settlement monitoring, and the stratum has good self-stability and air tightness;
s5, stopping, checking and processing, performing waterproof and tunnel face stability construction, and cleaning dregs and reinforcing steel bars to a cutter head panel;
s6, restoring tunneling, and starting the shield machine to continue tunneling after the cutterhead is cleaned.
2. The method for large-scale pile group construction by shield cutting and grinding according to claim 1, wherein the step S5 comprises:
S51, performing construction by a water stop ring at the rear of the shield tail, wherein the water stop ring is selected as a3 rd-5 th ring at the rear of the shield tail according to the site situation, and injecting double-liquid slurry into a third full ring at the rear of the shield tail, wherein the grouting pressure is controlled to be 3.5bar, and each hole is injected with 0.8-1.5 cubic meters;
s52, injecting balance shield mud and deslagging replacement, wherein a synchronous grouting system is adopted, the balance ball valve of the soil bin wall is used for multipoint injection, the pressure of the soil bin is controlled to be 1.5bar, a screw machine is used for deslagging, the pressure fluctuation range is controlled to be 0.2bar, and a cutter head is slowly rotated in the injection process;
S53, grading pressurization and three-stage pressurization are carried out on the shield mud, wherein the front two stages are dynamically stabilized for 2 hours, and the last stage is stabilized for 6 hours to ensure that the position of the tunnel face of the shield mud material forms a mud wall;
S54, slurry gas replacement, step-down is carried out in a 1.6-1.8bar interval, 0.2bar is used as a first stage, natural depressurization is adopted, and pressure release time is closely observed and recorded.
3. The method for large-scale pile group construction by shield cutting and grinding according to claim 2, wherein the three-stage pressurizing pressure in the step S53 is 1.2-1.4bar, 1.4-1.6bar, 1.6-1.8bar, the shield body is retreated by 80-100mm during the second stage pressurizing process, the cutterhead is slowly rotated for 2-3 times, the rotating speed is 0.1-0.5rpm, and the cutterhead is not rotated as much as possible during the last stage pressurizing process.
4. The method of claim 3, wherein if the pressure stabilizing time of the depressurization in step S54 exceeds 6 hours, the step depressurization is performed by gas pressure maintaining, the air discharge amount of the air compressor is ensured to be not more than 10% within each pressure maintaining time range, and the pressure is reduced by a screw machine in a soil discharging manner until the pressure is reduced to the set working pressure.
5. The method for large-scale pile group construction by shield cutting and grinding according to claim 4, wherein said step S5 further comprises:
S55, airtight detection, namely, boosting the pressure from 0 to a design value for no more than 10 minutes, then keeping the air pressure to 1.6-1.8 bar, checking the air leakage phenomenon at the tail of a ground shield and the like if the air pressure is stable for more than 2 hours and no obvious change exists, simultaneously focusing on the air supply condition of an air compressor, keeping the working pressure of a soil bin at 1.7-1.8 bar, keeping the fluctuation value of the air pressure in the bin at no more than 0.05bar, and keeping the air supply amount for 2 hours less than 10% of the air supply capacity, so that the mud film is manufactured to meet the requirements;
if the airtight detection is not qualified, repeating steps S52 to S55.
6. The method for large-scale pile group construction by shield cutting and grinding according to claim 5, wherein said step S5 further comprises:
S56, first bin opening inspection, first soil bin entering inspection, tunnel face geology and cutter head opening condition, mud film effect verification, tunnel face dew-out condition and stratum sampling, and template blocking of the cutter head opening position, wherein a back square wood is supported on the inner wall of the soil bin, and the tunnel face stability is judged by combining the factors;
If it is determined that the tunnel face is unstable, the steps S52 to S56 are repeated.
7. The method for constructing the large-scale pile group by cutting and grinding of the shield machine according to claim 1, wherein in the tunneling process of the shield machine, the posture deviation correction amount of each ring of the shield machine is controlled within 4 mm; the synchronous grouting quantity and the propelling stroke are in a direct proportion relation, and the grouting pressure is not more than 0.4MPa.
8. The method for large-scale pile group construction by shield cutting and grinding according to claim 1, wherein in the step S5, if the opening of the cutterhead is blocked by dregs, a pick and a spade are used for cleaning until reaching the cutterhead panel; if the cutter head opening or the cutter is wound with the steel bar, the hydraulic steel bar shear is used for shearing.
9. The method for large-scale pile group construction by shield cutting and grinding according to claim 2, wherein in the step S52, wall hole grouting is started from two waists of the tunnel, top part is injected, bottom part is injected, and the grouting hole is closed after grouting; when in synchronous grouting, each grouting pipe is simultaneously performed, and the grouting pressure of the two grouting pipes at the lower side is properly increased.
10. The method according to claim 2, wherein in the step S52, the grouting process is performed outside the segment, synchronous grouting and secondary grouting after the wall are selected according to the control requirements of the constructed engineering on tunnel deformation and stratum settlement, and in order to cope with the floating of the formed segment in the region with abundant groundwater, the secondary grouting after the wall is performed in time in cooperation with ground monitoring and in-hole rechecking measurement after the lining segment is separated from the tail of the shield, so as to fill the gap between the segment and the ground.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410691192.9A CN118257604A (en) | 2024-05-30 | 2024-05-30 | Large-scale pile group construction method for shield cutting and grinding |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410691192.9A CN118257604A (en) | 2024-05-30 | 2024-05-30 | Large-scale pile group construction method for shield cutting and grinding |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118257604A true CN118257604A (en) | 2024-06-28 |
Family
ID=91613519
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410691192.9A Pending CN118257604A (en) | 2024-05-30 | 2024-05-30 | Large-scale pile group construction method for shield cutting and grinding |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118257604A (en) |
-
2024
- 2024-05-30 CN CN202410691192.9A patent/CN118257604A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105804758B (en) | Across constructing metro tunnel method on the rectangular top pipe of the shallow small spacing of earthing big cross section | |
| CN106050243B (en) | An ultra shallow buries the Multiple tunnel concurrent construction method of small spacing big cross section | |
| CN108442382B (en) | In-situ protection and enclosure soil-retaining structure for pressure pipeline crossing deep foundation pit and construction method | |
| CN110159284B (en) | Ultra-shallow soil covering and large longitudinal slope starting construction method for coastal hydraulic reclamation stratum shield machine | |
| CN105736004A (en) | Balanced shield mud air-pressure cabin opening pressure maintaining and wall protecting construction method for shield tunneling | |
| CN109322671B (en) | Method for getting rid of worn and trapped shield cutter | |
| CN114233385B (en) | Treatment method for mud-bursting water of inclined shaft | |
| CN111206937A (en) | Pile group construction method for removing intruding main body structure in shield interval | |
| CN113669073B (en) | Construction method for controlling adjacent building deformation of water-rich sandy stratum by tunneling before station | |
| CN110984221A (en) | Construction method for reinforcing end socket at initial end of air shaft and guide wall structure | |
| CN111519679A (en) | Rapid grooving construction method for micro-weathering rock of diaphragm wall | |
| CN111997639A (en) | Method for getting rid of trouble and reinforcing and improving geology of TBM construction tunnel bad geology section card machine | |
| CN107489433A (en) | A kind of tunnel CRD engineering methods anti-leakage structure and Antiseep method | |
| CN114045870B (en) | Ultra-deep foundation pit group asynchronous excavation forward and backward combination safety construction method | |
| AU2021101943A4 (en) | A construction control method for a subway shield to penetrate through existing buildings | |
| CN113309526B (en) | Construction method for excavation and supporting of buckling arch of subway station | |
| CN109356195A (en) | Open-cut box culvert jacking method and system for crossing operation subway interval | |
| CN211898541U (en) | Guide wall structure for reinforced structure of air shaft initial end head | |
| Chen et al. | Construction technology of large diameter underwater shield tunnel | |
| CN118257604A (en) | Large-scale pile group construction method for shield cutting and grinding | |
| CN112502719B (en) | Method for TBM construction of lens body altered through high-pressure water-rich | |
| CN105507322B (en) | The stake of foundation ditch steel pipe plug is dry in immersed tube tunnel cofferdam cuts off method | |
| CN114542092A (en) | Shield receiving construction method without bottom plate structure | |
| CN109707394B (en) | Construction method for subway tunnel shield receiving end tunnel portal | |
| CN113684838A (en) | Grooving construction method for rock-socketed ultra-deep underground diaphragm wall |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination |