CN115929316A - Construction method for entering warehouse under pressure - Google Patents

Abstract

The invention discloses a construction method for entering a warehouse under pressure, which comprises the following steps: determining the working air pressure of the muddy water bin; continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant; detecting whether the ground at the position of the muddy water bin has ground settlement or not; detecting whether gas leakage occurs on the ground at the position of a cutter head of the shield equipment; ventilating the muddy water bin, and detecting the toxicity of gas exhausted from the muddy water bin. According to the pressurized feeding construction method, the collapse risk, the air leakage risk and the toxic gas risk of the muddy water bin can be checked, so that the internal environment of the muddy water bin meets the feeding requirement of workers, and the safety of the construction environment is ensured.

Description

Construction method for entering warehouse under pressure

Technical Field

The invention relates to the field of constructional engineering construction, in particular to a construction method for entering a warehouse under pressure.

Background

The shield equipment is the key for success and failure of the project of the ultra-large diameter shield tunnel, and the ultra-large diameter shield tunnel inevitably encounters a plurality of soil layers in the tunneling process due to the cross section size and the structure top earthing requirement, so that the shield equipment needs higher reliability and technical advancement to meet the complex environments such as hydrology, geology and buildings along the line which may appear at the site of the tunnel.

In the building construction engineering, the problems of cutter damage, row stagnation in a warehouse and the like can be encountered during shield tunneling, workers are required to enter the warehouse for replacement at the moment, the warehouse entry operation is a link with large risk in the shield construction process, and the workers can enter the warehouse only after the stability of an excavation surface is ensured. However, the prior art lacks effective detection measures in the storehouse, cannot judge whether the inside of the muddy water storehouse is safe or not, and cannot ensure safe operation of workers after entering the storehouse.

Disclosure of Invention

The invention mainly aims to provide a construction method for entering a muddy water cabin under pressure, and aims to solve the technical problem that whether the interior of the muddy water cabin is safe or not cannot be judged due to the lack of effective detection measures in the cabin in the prior art.

In order to achieve the purpose, the invention provides a construction method for entering a warehouse under pressure, which comprises the following steps:

determining the working air pressure of the muddy water bin;

continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant;

detecting whether ground settlement occurs on the ground where the muddy water bin is located;

detecting whether gas leakage occurs on the ground at the position of a cutter head of the shield equipment;

ventilating the muddy water bin, and detecting the toxicity of gas exhausted from the muddy water bin.

Optionally, the working air pressure of the muddy water bin is determined; it is right the muddy water storehouse lasts the air feed, makes the invariable step of muddy water storehouse internal gas pressure still includes:

determining the working air pressure of the muddy water bin;

excavating a muddy water bin, and replacing mud in the muddy water bin;

continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant;

and judging whether the pressure of the slurry bin can be continuously maintained, and if not, injecting new slurry to replace the original slurry.

Optionally, the operating air pressure of the muddy water sump is P = kyH;

wherein k is a static soil pressure coefficient, k =1-sin phi, phi is an effective internal friction angle, y is the volume weight of the soil body of the excavated stratum, and H is the thickness of the covering soil layer which is jacked to the ground on the tunnel face.

Optionally, the method further comprises the steps of:

forming a permeable mud film on the tunnel face by using slurry for tunneling of shield equipment;

preparing thick slurry and replacing the slurry in the slurry bin to form a compact mud skin-shaped mud film on the tunnel face;

communicating the air cushion bin with the muddy water bin, and replacing the air in the air cushion bin with the air in the muddy water bin;

adjusting the revolution of a dredge pump to reduce the liquid level of the slurry in the slurry bin;

and adjusting the opening of the communicating valve to adjust the air pressure of the muddy water bin to be working air pressure.

Optionally, before the step of forming a permeable mud-bearing film on the tunnel face by using the slurry for shield tunneling equipment, the method further includes:

increasing the grouting amount of the shield equipment to ensure that the outside of the segment of the cutter head of the shield equipment is closely filled;

secondary grouting is carried out at the shield tail of the shield equipment;

and increasing the injection amount of shield tail sealing grease of the shield equipment, so that the seal brush of the shield tail of the shield equipment is sealed.

Optionally, the method further comprises the steps of:

improving the air pressure of the muddy water bin and keeping the air pressure in the muddy water bin constant;

when the thickness of the mud film of the mud water bin meets the condition, reducing the air pressure of the mud water bin;

and pressing the slurry in the slurry bin out of the bin through air pressure, so that the air pressure of the slurry bin is adjusted to be working air pressure.

Optionally, the method further comprises the steps of:

closing the cabin door of the main cabin;

increasing the air pressure of the main cabin, and detecting whether the main cabin can reach the working air pressure or not;

reducing the air pressure of the main cabin, adjusting an air inlet valve and an air outlet valve of the main cabin, keeping a constant pressure reduction speed, and enabling an air inlet flow value to be at least: 0.5m3/min until the air pressure in the main cabin is the same as the outside normal pressure;

the front cabin was tested for air tightness in the same way.

Optionally, the method further comprises the steps of:

the staff enters the front cabin;

closing a cabin door of the front cabin and closing a sealing door between the front cabin and the main cabin;

opening an air inlet valve of the front compartment;

raising the air pressure of the front cabin until the working air pressure of the muddy water bin is reached;

increasing the air pressure of the main cabin, and opening an airtight door between the main cabin and the front cabin when the air pressure in the main cabin reaches the working air pressure of the muddy water bin;

and opening a sealing door between the main cabin and the air cushion cabin, entering the air cushion cabin, and then entering the muddy water cabin from the air cushion cabin.

Optionally, the method further comprises the steps of:

staff arrive at the front cabin and close the airtight doors of the main cabin and the front cabin;

reducing the pressure of the front cabin, and observing a pressure meter of the front cabin and an air inlet flow meter of the front cabin;

opening an exhaust valve of the front cabin for exhausting;

adjusting an air inlet valve and an air outlet valve of the front cabin to ensure that the air inlet flow value is at least: 0.5m3/min;

observing a pressure gauge of the front cabin, and adjusting an air inlet valve and an air outlet valve to keep the pressure constant within a specified time when the air pressure in the front cabin is reduced to a first-stage pressure value;

repeatedly adjusting an air inlet valve and an air outlet valve of the front cabin in the pressure maintaining process of the front cabin until the internal pressure of the front cabin is the same as the external air pressure;

and opening a cabin door between the front cabin and the outside.

Optionally, the method further comprises the steps of:

the staff enters the muddy water storehouse;

erecting and fixing an assembly platform;

registering the number of a damaged cutter, and taking a picture of the damaged cutter;

hanging the two chain blocks on lifting lugs above the muddy water bin respectively;

loosening the hob pressing block screw by using a pneumatic wrench, and then taking out the hob pressing block by using a jackscrew;

fixing the hob, lifting the hob out of the hob holder by using a chain block, cleaning the hob holder, installing the hob according to the steps in the opposite sequence, and registering the installation position of the new hob with the number;

fastening a bolt of a fixing rod to a prescribed torque;

cleaning the muddy water bin and closing the muddy water bin door.

The under-pressure warehousing construction method of the technical scheme comprises the following steps: determining the working air pressure of the muddy water bin; continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant; detecting whether ground settlement occurs on the ground where the muddy water bin is located; detecting whether gas leakage occurs on the ground at the position of a cutter head of the shield equipment; ventilating the muddy water bin, and detecting the toxicity of gas exhausted from the muddy water bin. According to the pressurized feeding construction method, the collapse risk, the air leakage risk and the toxic gas risk of the muddy water bin can be checked, so that the internal environment of the muddy water bin meets the feeding requirement of workers, and the safety of the construction environment is ensured.

Drawings

FIG. 1 is a schematic flow chart of an embodiment of a pressurized warehousing construction method of the present invention;

FIG. 2 is a schematic flow chart of an embodiment of an open-bin tool-changing workflow of the present invention;

fig. 3 is a schematic flow chart of a pressure holding test for confirming the opening of the bin according to an embodiment of the present invention.

The objects, features, and advantages of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely 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.

It should be noted that, if the present invention relates to directional indications (such as up, down, left, right, front, back, 8230; \8230;), the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture, and if the specific posture is changed, the directional indications are correspondingly changed.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In addition, if the meaning of "and/or" and/or "appears throughout, the meaning includes three parallel schemes, for example," A and/or B "includes scheme A, or scheme B, or a scheme satisfying both schemes A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Referring to fig. 1, in an embodiment of the pressurized bunker entry method in the present technical solution, the pressurized bunker entry method includes:

s10: determining the working air pressure of the muddy water bin;

s20: continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant;

s30: detecting whether ground settlement occurs on the ground where the muddy water bin is located;

s40: detecting whether gas leakage occurs on the ground at the position of a cutter head of the shield equipment;

s50: ventilating the mud water bin, and detecting the toxicity of gas exhausted from the mud water bin.

According to the pressurized feeding construction method, the collapse risk, the air leakage risk and the toxic gas risk of the muddy water bin can be checked, so that the internal environment of the muddy water bin meets the feeding requirement of workers, and the safety of the construction environment is ensured.

According to the technical scheme of the application, in one embodiment, the under-pressure warehousing construction method specifically comprises the following steps:

determination of working pressure for pressure feeding

According to geological and hydrological conditions of a position to be subjected to warehousing operation, the theoretical working pressure of the muddy water warehouse is calculated, the actual working pressure is 0.1-0.3bar lower than the theoretical working pressure, the phenomenon that a passage in a stratum in the middle and later stages of warehousing operation is opened due to the fact that the pressure is too high and compressed air does not enter in a hole to cause stratum air leakage is prevented, and the slightly lower air pressure value is beneficial to the health of warehousing operation personnel.

The muddy water storehouse operating pressure of this embodiment: p = kyH;

wherein k is a static soil pressure coefficient, k =1-sin phi, phi is an effective internal friction angle, y is the soil bulk density of the excavated stratum, and H is the thickness of a covering soil layer which is jacked to the ground on the tunnel face.

And performing field test according to the calculated theoretical working pressure, and determining the working pressure if the tunnel face is stable. Before the cabin is opened in the pneumatic operation, the formation condition is required to be confirmed to meet the requirement of gas pressure maintaining, and the pneumatic operation cannot be carried out under the condition that the gas pressure cannot be ensured. And a pressure maintaining experiment is carried out before the first opening of the warehouse, and the pressure is maintained for more than 1 hour, and all gate valves are ensured to work effectively.

Pressure and pressure test for man brake

And after the shield machine is put into the well, a man-brake air tightness test must be carried out before the first operation under pressure, so that the air tightness of the man-brake can reach the standard under the maximum working pressure. During the test, no personnel are required to enter, and only the unmanned pressure test is carried out to check the working conditions of all functional parts of the main cabin and the front cabin under the test pressure.

(1) Pressurization of the main tank

Checking display instruments, recorders, heating, clocks, thermometers, emergency telephones, sealing valves and the like, and checking the cleanliness of the sealing door;

opening a belt recorder of the main cabin, and checking whether the work is normal or not and whether the paper belt is enough or not;

closing the door of the main cabin to ensure the correct closing;

closing the main cabin wall sealing door and closing the sealing door between the main cabin and the front cabin;

the manhole chamber manager slowly opens the air inlet valve;

slowly raising the pressure of the main chamber until the working pressure is reached;

when the pressure in the main cabin reaches the working pressure, the manhole cabin manager closes the belt recorder.

(2) Main deck decompression

(1) The manhole cabin manager opens the belt recorder;

(2) reducing the pressure of the main cabin, and observing a pressure meter and an air inlet flowmeter of the main cabin;

(3) meanwhile, the manhole chamber manager opens the exhaust valve at the same time and starts to exhaust, and the pressure cannot rise again at any time;

(4) adjusting the intake valve and the exhaust valve until the slow and constant pressure reduction speed specified by the exhaust process is reached, wherein the flow value of the intake flowmeter is at least: 0.5m3/min;

(5) and observing the pressure gauge of the main cabin, and when the air pressure in the main cabin is reduced to a first-stage pressure value, a manhole cabin manager keeps the pressure constant within a specified time by adjusting the exhaust valve and the air inlet valve. A manhole chamber manager should frequently check the exhaust condition of the manhole chamber through a main chamber intake flowmeter;

repeating the steps (3) to (5) in the pressure maintaining process until the pressure in the cabin is the same as the normal pressure of the outside;

the manhole chamber supervisor closes the strip recorder and records the depressurization process (date, time, pressure, etc.) on the manhole chamber log book.

(3) Forebay pressurization

Checking display instruments, recorders, heating, clocks, thermometers, emergency telephones, sealing valves and the like, and checking the cleanliness of the sealing door;

opening a belt recorder of the front cabin, and checking whether the work is normal or not and whether the paper belt is enough or not;

closing the front cabin door to ensure the correct closing;

a sealing door between the front cabin and the main cabin is closed to ensure correct closing;

the manhole chamber manager slowly opens the air inlet valve;

slowly raising the pressure of the front compartment until the working pressure is reached;

when the pressure in the front chamber reaches the working pressure, the manhole chamber manager closes the belt recorder.

(4) Forebay decompression

(1) The manhole cabin manager opens the belt recorder;

(2) reducing the pressure of the front cabin, and observing a front cabin pressure meter and an air inlet flowmeter;

(3) meanwhile, the manhole chamber manager opens the exhaust valve at the same time to start exhausting, and the pressure cannot rise again at any moment;

(4) adjusting the intake valve and the exhaust valve until reaching a slow and constant pressure reduction speed specified by the exhaust process, wherein the flow rate value of the intake air flow meter is at least: 0.5m3/min;

(5) and observing a front cabin pressure gauge, and when the air pressure in the front cabin is reduced to a first-stage pressure value, a manhole cabin manager keeps the pressure constant within a specified time by adjusting an exhaust valve and an air inlet valve. A manhole chamber manager should frequently check the exhaust condition of the manhole chamber through a front chamber air inlet flow meter;

repeating the steps (3) to (5) in the pressure maintaining process until the pressure in the cabin is the same as the normal pressure of the outside;

the manhole chamber supervisor closes the strip recorder and records the depressurization process (date, time, pressure, etc.) on the manhole chamber log book.

Throughout the test procedure, it is necessary to ensure that all procedures are normal.

Air compressor inspection

In order to ensure the safety of the air compressing operation, the electrical and mechanical elements of the two electric air compressors are required to be inspected and maintained in an all-around way, and simultaneously, in order to ensure the continuity of power supply, a diesel generator is required to be prepared.

Checking all air filters, oil filters and the like, and replacing the air filters, the oil filters and the like if the air filters, the oil filters and the like are not qualified;

checking whether the oil levels of the screw oil and the diesel oil are enough;

checking whether the cooler can be normally used;

checking whether the electrical element is in a normal working state;

checking whether mechanical elements are in a normal working state, such as a triangular belt and the like;

checking whether the electric quantity of a diesel generator (standby) storage battery is enough and the work is normal;

inspection of man gates

Under high air pressure, the following items were checked:

the pressure sensor in the cabin must be able to work normally; emergency lighting must be able to illuminate normally; emergency calls must be able to talk normally; each pressure gauge must be able to display normally; the main cabin and the front cabin thermometers show normal; the main cabin and the front cabin are respectively provided with one clock and can work normally; the pressure of overflow valves of the main cabin and the front cabin is adjusted to 2.5-2.8bar; each manual ball valve switch must be normal; the flowmeter must work normally; each sealing door switch must be normal; the independent video monitoring system is normal, and the automatic fire-fighting spraying system is normal.

Before a real-time detection system for harmful gas in an operating environment performs normal air pressure warehouse opening operation, an electromechanical engineer needs to check related equipment related to air pressure operation one by one, and a main checking system comprises a man gate system, an air pressure adjusting system, an automatic pressure maintaining system, an air supply system, a ventilation system, a communication system, a fire fighting system and a power supply system. If the equipment has faults, the air pressure operation is carried out after the equipment faults are eliminated.

Before each warehousing operation, the working environment needs to be checked: the man gate and the air pressure cabin are not required to be provided with oil stains and oil-stained objects, combustible residues are not required to be provided, flammable and explosive objects such as cigarette ends, matches, lighters, beverage bottles and paper scraps cannot be brought or reserved, the internal environment of the man gate is neat, the lookout window is clean and transparent, and an operator can make inspection records.

Gas detection equipment inspection

Before the air pressure opening operation, a construction unit and a third-party detection unit detect the gas in the shield muddy water bin through a pressure relief valve port according to actual conditions; in the process of opening the warehouse, the contents of toxic and harmful gases, combustible gases, explosive gases and oxygen are required to be continuously detected; before and after opening the bin, continuous ventilation in the opened bin is both dealt with.

Equipment and supplies preparation

Preparing shield tunneling machine equipment: and the mechanical equipment and instruments related to opening the warehouse of the shield tunneling machine are ensured to be intact.

Mechanical equipment and instruments related to opening the bin are well constructed.

Preparing for electricity utilization: the diesel generator is added besides the existing power system, so that the air compressor can continuously supply air, the air supply system is provided with a standby air compressor, the air compressor is an oil-free air compressor, and the air supply capacity of the air compressor can meet the requirements of maintaining the stable stratum gas loss amount and the normal working gas circulation amount of the working surface.

Preparing water in the bin: and (5) checking a pipe valve and water pressure of the shield tunneling machine for supplying water into the bin to ensure that tap water in the bin is supplied.

An in-bin communication system:

the communication system is preferably a waterproof vibration-damping telephone; telephones are respectively arranged outside the excavation bin, in the main bin and in the auxiliary bin; emergency communication equipment (interphone) should be equipped; placing a writing tool at the gate; a camera is preferably arranged in the bin, and the inside of the excavated bin can be monitored at any time outside the bin; preparing oxygen supply: 5 sets of small medical oxygen inhalators were prepared.

Personnel preparation

According to the requirement of compressed air operation time, the operation of entering a muddy water cabin each time can not exceed 4 hours, the operation of entering the cabin is divided into 4 groups, each group comprises 3 persons, and each group works for 4 hours. Before the warehouse entry operation, a detailed operation instruction book is made, all participators are trained, the warehouse entry operation personnel have safety skills and emergency capacity of the warehouse entry operation under pressure, safety education training and safety technology are accepted according to the regulations, and the examination is qualified;

before entering the warehouse, the physical state and the carried articles of the warehouse-entering operation personnel are checked by the warehouse operator and the medical personnel, the personnel certificate and the training education delivery are checked by the professional security personnel, and the air pressure operation manager is in charge of the master control. The chemical fiber fabric and fur clothing should be selected as the all cotton fabric clothing strictly forbidden, and the gloves, rags and the like must be the all cotton fabric and must not have oil stain. Combustible and explosive substances such as gasoline, alcohol, acetyl and the like are forbidden to be brought in, and articles such as mobile phones, matches, cigarettes, lighters, closed water cups, aerated beverages and the like are forbidden to be brought into a warehouse. And (4) appointing a full-time observer to observe the air compressor, recording the loading and unloading time of the air compressor, and reporting in time when abnormity is found.

Making mud film and lowering liquid level

Slurry is replaced in the muddy water bin before opening the bin, a mud film is manufactured, and underground water on the tunnel face is prevented from entering the muddy water bin or high-pressure gas in the muddy water bin overflows from the tunnel face. After the mud film is manufactured, the liquid level in the mud water bin is reduced, and space is provided for subsequent warehousing work. The mud film preparation process is as follows:

(1) The synchronous grouting amount is increased when the shield is driven to the front 10 rings of the cutter changing position, the outside of the duct piece is ensured to be densely filled, secondary grouting is carried out on the 4 th to 10 th rings of the shield tail through duct piece grouting holes if necessary, and underground water is prevented from entering a muddy water bin from the rear of the shield tail;

(2) The injection amount of the shield tail sealing grease is properly increased, the pressure of a grease cavity is ensured, and the shield tail sealing brush is ensured not to leak air;

(3) Using slurry for tunneling to form a permeable mud film on the tunnel face under the action of muddy water pressure;

(4) Preparing thick slurry and replacing slurry used for tunneling in a slurry bin to form a compact mud skin-shaped mud film on the tunnel face;

(5) And reducing the liquid level, starting a circulation system, opening a communicating valve of the air cushion bin and the muddy water bin, and opening a sludge pump to enable compressed air in the air cushion bin to enter the muddy water bin for gas replacement. And the revolution of the sludge pump and the opening of the communicating valve are adjusted to be balanced, the liquid level in the muddy water bin is reduced to the working liquid level, and an air bin with the working pressure P is formed in the muddy water bin.

Requirement for mud film production

(1) The slurry mixing material for preparing the mud film is easy to mix, high in viscosity and high in slurry making rate, the slurry is mixed in the slurry barrel, and the concentration of the slurry is better under the condition of ensuring the injectability of the slurry.

(2) And a pressurization test is required, and the pressure of the slurry in the bin is increased so as to be beneficial to forming a thicker mud film. After pressurization, the pressure is kept at a high pressure for 1 hour to ensure that a thick enough mud film is formed.

(3) After the pressure is reduced, gas replacement slurry is needed, and the slurry in the slurry bin is pressed out of the bin through air pressure to form an air bin in a working air pressure state.

Examination of opening of the warehouse

In order to carry out the warehouse-opening inspection and the tool changing operation orderly, the whole warehouse-opening construction process is executed strictly according to the related warehouse-opening management and control program. Please refer to fig. 2 for the working procedure of opening the magazine and exchanging tools.

Bin opening confirmation

Carrying out a pressure maintaining test before opening the warehouse, keeping the working air pressure for more than 2 hours after the required air pressure is determined, monitoring the air supply condition of an air compressor by observing the change condition of the air pressure in the warehouse, simultaneously carrying out settlement observation on the ground, checking the 30mX30m range of the position of a ground cutterhead to see whether the air leaks, so as to judge whether the tunnel face is stable, and further determining whether the warehouse opening condition is met;

ventilating the gas bin and the muddy water bin for more than half an hour by adopting the air conveying and exhausting body, and detecting whether the exhausted gas in the bin meets the requirement by using a toxic gas detector until the gas meets the requirement of opening the bin;

when the requirements of opening the warehouse are met, according to the requirements of warehouse opening management and control programs, after being signed and confirmed by each related responsible person, the warehouse door can be opened after being finally signed and confirmed by a project manager, approval and supervision engineer.

Referring to fig. 3, the warehouse-opening confirmation further includes a pressure-holding test step, which includes:

determining the working air pressure of the muddy water bin;

excavating a muddy water bin, and replacing mud in the muddy water bin;

continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant;

and judging whether the muddy water bin can continuously maintain the pressure, and if not, injecting new mud to replace the original mud.

Warehouse entry

The step of entering the cabin means that a worker firstly enters the man gate, then the air pressure in the man gate is slowly increased to reach the same air pressure of the working chamber, the worker enters the air cushion cabin from a door between the man gate at the upper part and the air cushion cabin, and then enters the muddy water cabin through the door between the air cushion cabin and the muddy water cabin to perform tool changing under pressure.

The man lock comprises a front cabin and a main cabin, wherein the front cabin is mainly used for feeding materials into the main cabin or entering people, the main cabin is a medium for connecting the air cabin and the front cabin, and the working chamber and the man lock inlet chamber can be accessed by lifting air pressure. The operation of the gatekeeper is performed by a gatekeeper trained professionally. Various operating and display elements required by the gatekeeper are located outside the gatekeeper. Only those qualified for physical examination and appropriately trained professionals are allowed to enter the gate.

(1) The staff enters the front cabin

Checking whether the display instrument, the heating device, the clock, the thermometer, the telephone, the emergency telephone, the valve and the cabin door sealing member are clean;

closing the front cabin door to ensure the correct closing;

closing a sealing door between the front cabin and the main cabin;

using a telephone to enable a person on duty in the gatekeeper to keep in contact with the persons in the gatekeeper;

the man-brake attendant slowly opens the intake valve;

slowly increasing the pressure of the front cabin until the working pressure is reached, stopping pressurizing if the personnel in the gate have slight discomfort (such as headache, eardrum obstruction, nasal obstruction and other symptoms) in the pressurizing process, and withdrawing the personnel in the cabin;

personnel in the front cabin can adjust the heating device according to the requirements;

when the pressure in the main cabin reaches the working pressure, people in the front cabin can open the airtight door between the main cabin and the front cabin to enter the main cabin;

at the moment, the air pressure of the main cabin is equal to that of the muddy water cabin, the working pressure is the working pressure, and a worker can open a sealing door between the main cabin and the air cushion cabin to enter the air cushion cabin and then enter the muddy water cabin for operation through the air cushion cabin.

(2) Forebay decompression

(1) When the staff reaches the limited working time (or discomfort occurs), decompression needs to be carried out, and the method comprises the following specific steps:

(2) the staff arrives at the front cabin and closes the airtight doors of the main cabin and the front cabin;

(3) the personnel in the main cabin contact with the gate attendant by using a telephone;

(4) reducing the pressure of the front cabin according to the requirement of a decompression meter, and observing a front cabin pressure meter and a front cabin air inlet flow meter;

(5) meanwhile, a person on duty opens the exhaust valve at the same time to start exhausting, and the pressure can not rise again at any time;

(6) adjusting the intake valve and the exhaust valve until reaching a slow and constant pressure reduction speed specified by the exhaust process, wherein the flow rate value of the intake air flow meter is at least: 0.5m3/min;

(7) observing a front cabin pressure gauge, and when the air pressure in the front cabin is reduced to a first-stage pressure value, keeping the pressure constant within a specified time by a man gate attendant through regulating an air inlet valve and an air outlet valve, wherein the man gate attendant needs to frequently check the exhaust condition of the man gate through an air inlet flow meter;

(8) repeating the steps (5) to (6) in the pressure maintaining process until the pressure in the cabin is the same as the normal pressure of the outside, and opening a heating device by a person in the man gate in the pressure reducing process, wherein the recommended temperature is 15-28 ℃.

(9) Opening a cabin door between the front cabin and the outside, and enabling personnel to come out of the front cabin;

the r man gate attendant records the depressurization process (date, time, pressure, number of people, etc.) on the man gate record book;

after the pressure reduction, it is necessary to ensure that the personnel working under pressure have a rest for a certain time at the workplace, according to the regulations concerning the pressure reduction;

in the whole decompression process, all the processes are required to be ensured to be normal. The warehouse operator and the medical staff should make a related pressure reduction scheme according to the operation time, and the pressure reduction scheme should consider factors such as high temperature and labor intensity in the operation process, so as to reduce the incidence of pressure reduction diseases. The depressurization process must be performed strictly according to a depressurization protocol. And after the pressure reduction is finished and the articles are discharged from the man gate, checking the articles in the warehouse which are taken out by the operating personnel by the flight and plane electrical engineer.

(3) Pressure-increasing and-reducing operator

The entire pressurization and depressurization operation is performed by professionals trained to operate the cabin, and each worker must comply with the schedule. During pneumatic operation, the operator on duty must control the pressure of the gate. The responsibilities are as follows:

and the operator can not leave the working position in the working process.

The gate pressure was controlled according to standard procedures for pressurization and depressurization.

Once an emergency (such as tunnel face collapse, water burst and sand burst, pressure instability and the like) occurs, personnel in the bin must be informed to stop working, reduce pressure and leave the bin, and report to a main pipe of air compression working.

In each air compressing operation, the pressurizing time, the working time and the depressurizing time of the operation must be recorded and stored.

Before the operator enters the air compression environment, no operation record is required within 24 hours.

Identification of operating conditions

The first opening of the warehouse is firstly carried out by experienced engineers to enter the working conditions in the appraisal warehouse, including the face geological conditions, the cutter abrasion condition, the muddy water warehouse cleaning condition and the like, and the internal conditions are photographed so as to be analyzed and processed after being taken out of the warehouse. After careful observation, other personnel can carry out the next operation on the muddy water bin after judging safety.

Cutter head cleaning and supporting

After entering the muddy water bin, a worker firstly observes whether the tunnel face is stable or not for inspection. And (4) immediately supporting when necessary, and cleaning the cutter disc under the condition of ensuring safety.

Checking condition of cutter head, tool, etc

The inspection of the cutter head, the cutters and the mud cake formation condition are carried out by groups, each group consists of 3 experienced and energetic skilled workers, one worker enters the muddy water bin, and the other two workers monitor and record at the entrance of the muddy water bin. The working time of each worker in the warehouse depends on the condition of the worker, but the maximum time is not more than 2 hours. After the position of one cutter is checked, the personnel exit the muddy water bin, rotate the cutter head and check the position of the next cutter.

Tool changing device

(1) Tool changing procedure

After entering the muddy water bin, a cutter changing worker firstly cleans a cutter to be changed, and then changes the cutter according to the following steps:

erecting and fixing the assembly platform, and ensuring the stability and convenience of the assembly platform;

firstly, registering the number of a damaged cutter, and taking a picture of the damaged cutter;

respectively hanging the two chain hoists on the two lifting lugs above the muddy water bin;

loosening the hob pressing block screw by using a pneumatic wrench, and taking out the hob pressing block by using a jackscrew;

tying the hob with a small sling of two tons, slowly pulling the hob out of the hob seat by a chain block, cleaning the hob seat, installing the hob according to the steps in the reverse order, and registering the installation position of the new hob with the number;

after the hob is replaced, the bolt of the fixing rod is fastened to a specified torque. The cap nut is the same as the locking nut, and plays the roles of locking the bolt, protecting and threading.

After the cutter is replaced, the muddy water bin can be cleaned, and the muddy water bin door is closed. After the person quits, tries to rotate the cutter head for a plurality of circles, the person is arranged to enter the muddy water bin tightening cutter, after tightening is confirmed, the muddy water bin and the front of the cutter head are comprehensively checked, tools and sundries are prevented from being left in the muddy water bin, the group leader checks the number of the person, the person is confirmed to retreat out of the muddy water bin without errors, and a muddy water bin door is closed.

(2) Tool changing standard

Cutter head and tool changing standard: controlling the diameter of the excavation to be 19 inches and 1.5CM; 19 inches of edge hob is 2CM; 19 inch noodle cutter 2CM; the size of the center double-edged knife is 1.5-2CM.

The sharpening and thinning of the cutter ring can also be considered to be replaced.

The cutter is found to be eccentric, the cutter ring is broken and the cutter ring is damaged and needs to be replaced immediately.

When the front hob is installed, the side of the retainer ring close to the center of the cutter head is used as the front, and a spring pad is required to be added to an installation bolt.

The outer edge of the large scraper is worn to the cutter holder, so that replacement can be considered.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. The construction method for entering the warehouse under pressure is characterized by comprising the following steps:

determining the working air pressure of the muddy water bin;

continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant;

detecting whether ground settlement occurs on the ground where the muddy water bin is located;

detecting whether gas leakage occurs on the ground at the position of a cutter head of the shield equipment;

ventilating the muddy water bin, and detecting the toxicity of gas exhausted from the muddy water bin.

2. The under-pressure warehouse entry construction method according to claim 1, wherein the working air pressure of the muddy water warehouse is determined; it is right the muddy water storehouse lasts the air feed, makes the invariable step of muddy water storehouse internal gas pressure still includes:

determining the working air pressure of the muddy water bin;

excavating a muddy water bin, and replacing mud in the muddy water bin;

continuously supplying air to the muddy water bin to ensure that the air pressure in the muddy water bin is constant;

and judging whether the muddy water bin can continuously maintain the pressure, and if not, injecting new mud to replace the original mud.

3. The under-pressure warehousing construction method of claim 1, characterized in that the working air pressure of the muddy water silo is P = kyH;

wherein k is a static soil pressure coefficient, k =1-sin phi, phi is an effective internal friction angle, y is the volume weight of the soil body of the excavated stratum, and H is the thickness of the covering soil layer which is jacked to the ground on the tunnel face.

4. The under-pressure warehousing construction method according to claim 1, characterized by further comprising the steps of:

forming a permeable mud film on the tunnel face by using slurry for tunneling by shield equipment;

preparing thick slurry and replacing the slurry in the slurry bin to form a compact mud skin-shaped mud film on the tunnel face;

communicating the air cushion bin with the muddy water bin, and replacing the air in the air cushion bin with the air in the muddy water bin;

adjusting the revolution of a dredge pump to reduce the liquid level of the slurry in the slurry bin;

and adjusting the opening of the communicating valve to adjust the air pressure of the muddy water bin to be working air pressure.

5. The under-pressure warehouse entry construction method according to claim 4, wherein before the step of forming a permeable mud-bearing film on the tunnel face by using the slurry for shield tunneling, the method further comprises:

increasing the grouting amount of the shield equipment, and tightly filling the outside of the segment of the cutter head of the shield equipment;

secondary grouting is carried out at the shield tail of the shield equipment;

and increasing the injection amount of shield tail sealing grease of the shield equipment, so that the seal brush of the shield tail of the shield equipment is sealed.

6. The under-pressure warehousing construction method according to claim 4, characterized by further comprising the steps of:

improving the air pressure of the muddy water bin and keeping the air pressure in the muddy water bin constant;

when the thickness of the mud film of the mud water bin meets the condition, reducing the air pressure of the mud water bin;

and the mud in the mud bin is pressed out of the bin through air pressure, so that the air pressure of the mud bin is adjusted to be working air pressure.

7. The under-pressure warehousing construction method according to claim 1, characterized by further comprising the steps of:

closing a cabin door of the main cabin;

increasing the air pressure of the main cabin, and detecting whether the main cabin can reach the working air pressure or not;

reducing the air pressure of the main cabin, adjusting an air inlet valve and an air outlet valve of the main cabin, keeping a constant pressure reduction speed, and enabling an air inlet flow value to be at least: 0.5m3/min until the air pressure in the main cabin is the same as the outside normal pressure;

the front compartment was tested for air tightness in the same manner.

8. The under-pressure warehousing construction method according to claim 1, characterized by further comprising the steps of:

the staff enters the front cabin;

closing a cabin door of the front cabin and closing a sealing door between the front cabin and the main cabin;

opening an air inlet valve of the front cabin;

raising the air pressure of the front cabin until the working air pressure of the muddy water bin is reached;

raising the air pressure of the main cabin, and opening an airtight door between the main cabin and the front cabin when the air pressure in the main cabin reaches the working air pressure of the muddy water bin;

and opening a sealing door between the main cabin and the air cushion cabin, entering the air cushion cabin, and then entering the muddy water cabin from the air cushion cabin.

9. The under-pressure warehousing construction method according to claim 8, characterized by further comprising the steps of:

staff arrive at the front cabin and close the airtight doors of the main cabin and the front cabin;

reducing the pressure of the front cabin, and observing a pressure meter of the front cabin and an air inlet flow meter of the front cabin;

opening an exhaust valve of the front cabin for exhausting;

adjusting an air inlet valve and an air outlet valve of the front cabin to ensure that the air inlet flow value is at least: 0.5m3/min;

observing a pressure gauge of the front cabin, and adjusting an air inlet valve and an air outlet valve when the air pressure in the front cabin is reduced to a first-stage pressure value, and keeping the pressure constant within a specified time;

repeatedly adjusting an air inlet valve and an air outlet valve of the front cabin in the pressure maintaining process of the front cabin until the internal pressure of the front cabin is the same as the external air pressure;

and opening a cabin door between the front cabin and the outside.

10. The under-pressure warehousing construction method according to claim 1, characterized by further comprising the steps of:

the staff enters the muddy water storehouse;

erecting and fixing an assembly platform;

registering the number of a damaged cutter, and taking a picture of the damaged cutter;

hanging the two chain blocks on lifting lugs above the muddy water bin respectively;

loosening the hob pressing block screw by using a pneumatic wrench, and then taking out the hob pressing block by using a jackscrew;

fixing the hob, lifting the hob out of the hob holder by using a chain block, cleaning the hob holder, installing the hob according to the steps in the opposite sequence, and registering the installation position of the new hob with the number;

fastening a bolt of a fixing rod to a prescribed torque;

cleaning the muddy water bin and closing the muddy water bin door.

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