CN118223896A - Automatic synchronous grouting control method for shield tunneling machine - Google Patents
Automatic synchronous grouting control method for shield tunneling machine Download PDFInfo
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- CN118223896A CN118223896A CN202410463731.3A CN202410463731A CN118223896A CN 118223896 A CN118223896 A CN 118223896A CN 202410463731 A CN202410463731 A CN 202410463731A CN 118223896 A CN118223896 A CN 118223896A
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- grouting
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- wall
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- 238000000034 method Methods 0.000 title claims abstract description 60
- 230000001360 synchronised effect Effects 0.000 title claims abstract description 16
- 230000005641 tunneling Effects 0.000 title claims description 15
- 239000004570 mortar (masonry) Substances 0.000 claims abstract description 20
- 238000009434 installation Methods 0.000 claims description 3
- 238000002347 injection Methods 0.000 abstract description 5
- 239000007924 injection Substances 0.000 abstract description 5
- 238000010276 construction Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007569 slipcasting Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
Abstract
The invention relates to the field of synchronous grouting for shield machines, and discloses an automatic synchronous grouting control method for a shield machine, which comprises the following steps of: acquiring the distance between the inner wall of the tail shield and the distance between the inner wall of the duct piece; step 2: calculating the shield tail gap volume between the segment and the shield tail inner wall according to the distance between the tail shield inner wall, the segment inner wall distance and the segment thickness; step 3: acquiring the real-time working speed of a grouting pump in the shield machine propelling process according to the shield tail clearance volume and the shield machine propelling speed; step 4: and controlling the grouting pump to inject mortar into the shield tail gap according to the real-time working speed and the grouting pressure value of the grouting pump. According to the scheme, the shield tail gap is calculated by measuring the shield tail gap and metering mortar into the grouting control system, the difference value between the mortar injection volume and the back wall gap volume is compared in real time in the pushing process of the shield machine, the grouting speed is dynamically adjusted, the grouting quantity can be accurately controlled by combining the reference grouting pressure, the conditions of leakage grouting and less grouting are avoided, the back wall holes are reduced, and the grouting quality is guaranteed.
Description
Technical Field
The invention relates to the field of synchronous grouting for shield machines, in particular to an automatic synchronous grouting control method for a shield machine.
Background
The quality of the grouting after the wall directly influences the fastening degree of the tunnel during the shield construction, so that a shield machine needs to be provided with a good grouting control system, and the uniformity of grouting after the wall is ensured without holes. In the traditional construction, two modes of manual grouting and automatic grouting are mainly adopted, and the amount and the grouting pressure of grouting are determined manually according to the experience of constructors, so that larger grouting deviation is easily caused; when automatic grouting is performed, grouting is controlled by setting grouting pressure of a grouting system, and grouting is stopped when certain pressure is reached, so that the method has too few reference indexes, and uneven grouting and void generation are easily caused. According to the method, grouting is controlled through single grouting pressure, whether grouting is enough or not is difficult to judge according to the single grouting pressure, and large grouting deviation and non-uniformity are easy to cause.
Disclosure of Invention
The invention aims to provide an automatic synchronous grouting control method for a shield machine, which aims to solve the problems that grouting is difficult to control by a single grouting pressure value at present, and grouting deviation is large and grouting is uneven easily caused.
In order to achieve the above purpose, the invention adopts the following technical scheme: an automatic synchronous grouting control method for a shield tunneling machine comprises the following steps:
step 1: acquiring the distance between a tail shield inner wall and a tail shield tail clearance measuring device on a segment erector, and simultaneously acquiring the distance between the tail shield clearance measuring device and the segment inner wall;
Step 2: calculating the shield tail gap volume between the segment and the shield tail inner wall according to the distance between the tail shield inner wall, the segment inner wall distance and the segment thickness;
step 3: acquiring the real-time working speed of a grouting pump in the shield machine propelling process according to the shield tail clearance volume and the shield machine propelling speed;
Step 4: and controlling the grouting pump to inject mortar into the shield tail gap according to the real-time working speed and the grouting pressure value of the grouting pump.
Preferably, the step 3 specifically includes: calculating the volume of mortar to be injected into the grouting pump according to the gap volume of the shield tail and the pushing speed of the shield machine, and obtaining the single round trip times of the piston of the grouting pump according to a formula V 1 = n x L x S, wherein V 1 is the total grouting amount, n is the round trip times of the piston, L is the single stroke of the grouting pump, and S is the cross section area of the grouting piston; and then the real-time working speed of the grouting pump in the propelling process is obtained according to the single round trip times of the grouting pump piston.
Preferably, in the step 4, a grouting speed value and a grouting pressure value in the grouting process of the grouting pump are obtained, and then the grouting speed and the grouting pressure in the grouting process of the grouting pump are adjusted according to the grouting speed value, the grouting pressure value, the real-time working speed of the grouting pump and a preset threshold value of the grouting pressure.
Preferably, the grouting speed of the grouting pump in the step 4 is greater than the grouting amount required by the real-time working speed of the grouting pump in the propulsion process, and when the grouting pressure value is equal to or greater than the preset percentage value of the preset grouting pressure threshold, the grouting speed is reduced until the grouting pressure is less than the preset increment of the grouting pressure threshold, and the preset percentage is greater than 100%.
Preferably, the grouting speed of the grouting pump in the step 4 is greater than the grouting amount required by the real-time working speed of the grouting pump in the pushing process, and when the grouting pressure value is smaller than the preset grouting pressure threshold value, the grouting speed is increased until the grouting pressure value is greater than or equal to the preset grouting pressure threshold value.
Preferably, when the grouting pressure value in the step 4 is greater than or equal to the preset grouting pressure threshold value and is smaller than the preset percentage value of the preset grouting pressure threshold value, and the grouting speed is smaller than the grouting amount required by the real-time working speed of the grouting pump in the pushing process, the grouting speed is adjusted to be matched with the pushing speed of the shield machine, so that the grouting amount is the same as the grouting amount required by the real-time working speed of the grouting pump in the pushing process; the preset percentage is greater than 100%.
Preferably, the shield tail clearance measuring device comprises a laser range finder, wherein the laser range finder is uniformly arranged on the periphery of the duct piece splicing machine, and the installation angle of the laser range finder corresponds to the angle of a tail shield grouting pipeline.
Preferably, the grouting pump in the step 4 injects mortar into the tail gap through a plurality of groups of grouting pipelines uniformly distributed in the tail shield. And the shield tail gaps are uniformly grouting through a plurality of groups of pipelines, so that grouting quality is ensured and grouting speed is increased.
Preferably, the step 2 specifically includes: and judging the parameters corresponding to the numerical values according to the distance value of the inner wall of the tail shield, the distance value of the inner wall of the segment and the thickness value of the segment, and then calculating the numerical values of the corresponding parameters to obtain the gap volume of the tail shield between the segment and the inner wall of the tail shield.
Preferably, the step 1 specifically includes: firstly, the distance between the shield tail clearance measuring device and the inner wall of the tail shield is read through the shield tail clearance measuring device, and then the distance between the shield tail clearance measuring device and the inner wall of the duct piece is read through the movable shield tail clearance measuring device.
According to the scheme, the shield tail clearance is measured and mortar is metered into a grouting control system, the shield tail clearance is calculated through a shield tail clearance measuring device, so that the wall back clearance volume is calculated, the mortar volume is injected through the mortar quantity, the difference between the mortar injection volume and the wall back clearance volume is compared in real time in the pushing process of a shield machine, the grouting speed is dynamically adjusted, the grouting quantity can be accurately controlled by combining with the reference grouting pressure, the total grouting quantity V can be slightly larger than the grouting quantity required by the pushing speed in practice, the grouting quantity is properly increased, the grouting quantity can be used for judging whether a wall back cavity or hole is generated, if the grouting quantity reaches V, the slurry overflows from a top grouting port in a small quantity at the moment, the full grouting can be judged, if the grouting quantity does not reach V, but the top grouting port overflows in a large quantity, the possibility of holes for leakage grouting are probably generated behind the wall, and the grouting quantity is timely adjusted or other emergency measures are adopted; the real-time working speed of the grouting pump in the advancing process is obtained through the advancing speed of the shield machine, and then the grouting speed is adjusted according to the real-time working speed, so that the aim of synchronous grouting of the shield machine is fulfilled, and the working efficiency, grouting speed and quality of the shield machine are ensured.
Drawings
Fig. 1 is a schematic flow chart of a method for controlling automatic synchronous grouting of a shield tunneling machine according to an embodiment of the present invention.
Fig. 2 is a layout diagram of a laser rangefinder in accordance with an embodiment of the invention.
Detailed Description
The following is a further detailed description of the embodiments:
reference numerals in the drawings of the specification include: segment erector 1, tail shield 2, segment 3, laser range finder 4, slip casting pipeline 5.
Examples:
An automatic synchronous grouting control method for a shield tunneling machine, as shown in figure 1, comprises the following steps:
step 1: and obtaining the distance between the tail clearance measuring device on the duct piece assembling machine 1 and the inner wall of the tail shield 2, and meanwhile obtaining the distance between the tail clearance measuring device and the inner wall of the duct piece 3.
The method specifically comprises the following steps: firstly, the distance between the shield tail clearance measuring device and the inner wall of the tail shield 2 is read through the shield tail clearance measuring device, and then the distance between the shield tail clearance measuring device and the inner wall of the duct piece 3 is read through the moving shield tail clearance measuring device.
The shield tail clearance measuring device comprises a laser range finder 4, wherein the laser range finder 4 is uniformly arranged on the periphery of the duct piece assembling machine, and the installation angle of the laser range finder 4 corresponds to the angle of the tail shield 2 grouting pipeline 5. As shown in fig. 2, in this embodiment, there are 4 laser rangefinders 4 and 4 sets of grouting pipelines 5 of the tail shield 2, and each laser rangefinder 4 corresponds to the angle of the grouting pipeline 5 of the tail shield 2 at the corresponding position.
Step 2: and calculating the shield tail gap volume between the segment 3 and the shield tail inner wall according to the distance between the tail shield inner wall, the segment inner wall and the segment 3 thickness.
The method specifically comprises the following steps: and judging the parameters corresponding to the numerical values according to the distance value of the inner wall of the tail shield, the distance value of the inner wall of the segment and the thickness value of the segment 3, and then calculating the numerical values of the corresponding parameters to obtain the gap volume of the tail shield between the segment 3 and the inner wall of the tail shield.
In the step, a data processing comparison unit is adopted to process the measured value of the laser range finder 4 to obtain a shield tail gap volume within every 90 degrees, the specific process is that firstly, a shield tail inner wall distance value, a shield inner wall distance value and a shield 3 thickness value are received and obtained, parameter meanings corresponding to the values are judged according to the values, for example, the shield 3 thickness is 30cm generally, the maximum distance from a sensor to the shield 2 is not more than 100cm, so that the maximum value read by the sensor is not more than 100cm, the distance from the sensor to the shield 3 inner wall is at least 30cm different from the distance from the sensor to the shield 2 inner wall, the measured distance value is the shield tail distance or the shield inner wall distance through comparison analysis, the shield tail gap value can be obtained by subtracting the shield 3 thickness from the two values, the gap volume within the range of the sensor can be calculated through the value, and the gap volume is transmitted to a PLC processor and a control unit.
Step 3: and acquiring the real-time working speed of the grouting pump in the shield machine propelling process according to the shield tail clearance volume and the shield machine propelling speed.
In this step, the PLC processor and the control unit calculate the volume of the injected mortar of the grouting pump, and calculate the number of strokes of the grouting pump, where the formula is V 1 =n×l×s: v 1 is the total grouting amount; n is the number of piston trips; l is a single stroke of the grouting pump; s is the cross-sectional area of the grouting piston. The injection volume of the grouting pump is equal to the gap volume of the tail of the shield, the gap volume of the tail of the shield is V 2,V2＝Π(R2-r2 multiplied by c multiplied by t, R is the distance between the center of the splicing machine and the inner wall of the tail shield (namely the distance between the gap measuring device of the tail of the shield and the inner wall of the tail shield 2), R is the distance between the center of the splicing machine and the outer wall of the segment, R is equal to the distance between the center of the splicing machine and the inner wall of the segment plus the thickness of the segment (namely the distance between the gap measuring device of the tail and the inner wall of the segment 3 plus the thickness of the segment), c is the pushing speed of the shield machine, t is time, and the distance is obtained according to V 1＝V2 N/t is the speed of the grouting pump, the value measured by each sensor is substituted, the working speed of each grouting pump can be obtained, and the grouting pump is automatically controlled to work by combining the grouting pressure value.
Step 4: and controlling the grouting pump to inject mortar into the shield tail gap according to the real-time working speed and the grouting pressure value of the grouting pump.
In the step, a grouting speed value and a grouting pressure value in the grouting process of the grouting pump are obtained, and then the grouting speed and the grouting pressure in the grouting process of the grouting pump are adjusted according to the grouting speed value, the grouting pressure value, the real-time working speed of the grouting pump and the preset threshold value of the grouting pressure.
The working modes for controlling the grouting pump in the step specifically comprise the following three modes:
1. When the grouting speed of the grouting pump is greater than the grouting amount required by the real-time working speed of the grouting pump in the pushing process, and the grouting pressure value is equal to or greater than the preset percentage value of the preset grouting pressure threshold value, the grouting speed is reduced until the grouting pressure is smaller than the preset increment of the grouting pressure threshold value, and the preset percentage (120% in the embodiment) is greater than 100%.
2. When the grouting speed of the grouting pump is larger than the grouting amount required by the real-time working speed of the grouting pump in the pushing process and the grouting pressure value is smaller than the preset grouting pressure threshold value, the grouting speed is increased until the grouting pressure value is larger than or equal to the preset grouting pressure threshold value.
3. When the grouting pressure value is larger than or equal to a preset grouting pressure threshold value and smaller than a preset percentage value of the preset grouting pressure threshold value, and the grouting speed is smaller than the grouting amount required by the real-time working speed of the grouting pump in the pushing process, the grouting speed is adjusted to be matched with the pushing speed of the shield machine, so that the grouting amount is the same as the grouting amount required by the real-time working speed of the grouting pump in the pushing process; the preset percentage (120% in this embodiment) is greater than 100%. The value of the preset percentage in this step is the same as that of the first mode described above.
The grouting process of the grouting pump is controlled mainly through controlling grouting pressure, and ground bulge caused by overlarge grouting pressure is avoided.
In the grouting process, the total grouting amount V can be slightly larger than the grouting amount required by the propulsion speed (namely V 1, specifically calculated according to the shield tail clearance volume and the shield machine propulsion speed), the grouting amount is increased appropriately, and the grouting method can be used for judging whether a cavity or a hole behind a wall is generated or not, if the grouting amount reaches V, the grouting amount overflows from a top grouting port in a small amount, the full grouting can be judged, if the total grouting amount does not reach V, but the top grouting port overflows in a large amount, the possibility of generating a cavity is presumed, if the grouting amount reaches V, and if the grouting amount does not overflow from the top grouting port at the moment, the hole behind the wall possibly has leakage is judged, and then the grouting amount is adjusted in time or other emergency measures are taken.
In the step, the grouting pump injects mortar into the tail gap through a plurality of groups of grouting pipelines 5 which are uniformly distributed in the tail shield 2. And the shield tail gaps are uniformly grouting through a plurality of groups of pipelines, so that grouting quality is ensured and grouting speed is increased.
The step is implemented by an output execution unit, wherein the output execution unit comprises a grouting pump, a grouting pump control valve and four-way grouting pipelines 5, the control valve can output and adjust the stroke speed of the grouting pump through a PLC processor and the execution unit, and the stroke times and the grouting pressure of the grouting pump are fed back to the PLC processor and the execution unit.
According to the scheme, the real-time working speed of the grouting pump in the propelling process is obtained through the propelling speed of the shield machine, and then the grouting speed is adjusted according to the speed, so that the aim of synchronous grouting of the shield machine is fulfilled, and the working efficiency, the grouting speed and the grouting quality of the shield machine are ensured; the method is characterized in that shield tail gap measurement and mortar metering are put into a grouting control system, 4 laser rangefinder 4 devices are used for calculating shield tail gaps at 4 positions, so that the wall back gap volume can be calculated, the mortar injection volume is calculated through mortar metering, in the pushing process of a shield machine, the difference value between the mortar injection volume and the wall back gap volume is compared in real time, the grouting speed is dynamically adjusted, and the grouting quantity can be accurately controlled by referring to grouting pressure.
The foregoing is merely exemplary of the present application, and specific technical solutions and/or features that are well known in the art have not been described in detail herein. It should be noted that, for those skilled in the art, several variations and modifications can be made without departing from the technical solution of the present application, and in the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "fixed," etc. are to be construed broadly, and may be either a fixed connection, a removable connection, or an integral connection, for example; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances. The protection scope of the present application is subject to the content of the claims, and the description of the specific embodiments and the like in the specification can be used for explaining the content of the claims.
Claims (10)
1. An automatic synchronous grouting control method for a shield tunneling machine comprises the following steps:
step 1: acquiring the distance between a tail shield inner wall and a tail shield tail clearance measuring device on a segment erector, and simultaneously acquiring the distance between the tail shield clearance measuring device and the segment inner wall;
Step 2: calculating the shield tail gap volume between the segment and the shield tail inner wall according to the distance between the tail shield inner wall, the segment inner wall distance and the segment thickness;
step 3: acquiring the real-time working speed of a grouting pump in the shield machine propelling process according to the shield tail clearance volume and the shield machine propelling speed;
Step 4: and controlling the grouting pump to inject mortar into the shield tail gap according to the real-time working speed and the grouting pressure value of the grouting pump.
2. The method for automatically and synchronously grouting for the shield tunneling machine according to claim 1, which is characterized by comprising the following steps: the step 3 specifically includes: calculating the volume of mortar to be injected into the grouting pump according to the gap volume of the shield tail and the pushing speed of the shield machine, and obtaining the single round trip times of the piston of the grouting pump according to a formula V 1 = n x L x S, wherein V 1 is the total grouting amount, n is the round trip times of the piston, L is the single stroke of the grouting pump, and S is the cross section area of the grouting piston; and then the real-time working speed of the grouting pump in the propelling process is obtained according to the single round trip times of the grouting pump piston.
3. The method for automatically and synchronously grouting for the shield tunneling machine according to claim 1, which is characterized by comprising the following steps: and (4) acquiring a grouting speed value and a grouting pressure value in the grouting process of the grouting pump, and then adjusting the grouting speed and the grouting pressure in the grouting process of the grouting pump according to the grouting speed value, the grouting pressure value, the real-time working speed of the grouting pump and the preset threshold value of the grouting pressure.
4. The automatic synchronous grouting control method for the shield tunneling machine according to claim 3, wherein the method comprises the following steps: and (3) when the grouting speed of the grouting pump in the step (4) is larger than the grouting amount required by the real-time working speed of the grouting pump in the propelling process and the grouting pressure value is equal to or larger than the preset percentage value of the preset grouting pressure threshold value, the grouting speed is reduced until the grouting pressure is smaller than the preset increment of the grouting pressure threshold value, and the preset percentage is larger than 100%.
5. The automatic synchronous grouting control method for the shield tunneling machine according to claim 3, wherein the method comprises the following steps: and (3) when the grouting speed of the grouting pump in the step (4) is larger than the grouting amount required by the real-time working speed of the grouting pump in the pushing process and the grouting pressure value is smaller than the preset grouting pressure threshold value, the grouting speed is increased until the grouting pressure value is larger than or equal to the preset grouting pressure threshold value.
6. The automatic synchronous grouting control method for the shield tunneling machine according to claim 3, wherein the method comprises the following steps: when the grouting pressure value in the step 4 is larger than or equal to a preset grouting pressure threshold value and smaller than a preset percentage value of the preset grouting pressure threshold value, and the grouting speed is smaller than the grouting amount required by the real-time working speed of the grouting pump in the pushing process, the grouting speed is adjusted to be matched with the pushing speed of the shield machine, so that the grouting amount is the same as the grouting amount required by the real-time working speed of the grouting pump in the pushing process; the preset percentage is greater than 100%.
7. The method for automatically and synchronously grouting for the shield tunneling machine according to claim 1, which is characterized by comprising the following steps: the shield tail clearance measuring device comprises a laser range finder, wherein the laser range finder is uniformly arranged on the periphery of the duct piece assembling machine, and the installation angle of the laser range finder corresponds to the angle of a tail shield grouting pipeline.
8. The method for automatically and synchronously grouting for the shield tunneling machine according to claim 1, which is characterized by comprising the following steps: and (4) injecting mortar into the tail clearance by the grouting pump in the step through a plurality of groups of grouting pipelines uniformly distributed in the tail shield.
9. The method for automatically and synchronously grouting for the shield tunneling machine according to claim 1, which is characterized by comprising the following steps: the step 2 specifically includes: and judging the parameters corresponding to the numerical values according to the distance value of the inner wall of the tail shield, the distance value of the inner wall of the segment and the thickness value of the segment, and then calculating the numerical values of the corresponding parameters to obtain the gap volume of the tail shield between the segment and the inner wall of the tail shield.
10. The method for automatically and synchronously grouting for the shield tunneling machine according to claim 1, which is characterized by comprising the following steps: the step 1 specifically includes: firstly, the distance between the shield tail clearance measuring device and the inner wall of the tail shield is read through the shield tail clearance measuring device, and then the distance between the shield tail clearance measuring device and the inner wall of the duct piece is read through the movable shield tail clearance measuring device.
Publications (1)
| Publication Number | Publication Date |
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| CN118223896A true CN118223896A (en) | 2024-06-21 |
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