CN116291518A - TBM tunneling direction posture regulation and control method for large-diameter small-turn tunnel - Google Patents

Abstract

The invention discloses a method for controlling the direction and posture of a TBM with a large diameter and a small turn, belonging to the technical field of shield construction. position and attitude; when the distance is equal to the length of the TBM main engine, adjust the TBM to start digging in the direction of the inward bend of the turning section; when the distance from the entry point of the turning section is half the length of the TBM main engine, adjust the TBM to maintain the turning attitude; when just entering the turning section, Adjust the TBM construction method and excavation direction so that the excavation axis gradually fits to the design axis of the curved tunnel; during the turning excavation process of the TBM, adjust its excavation parameters and position its pose. The invention improves the overall passing efficiency of the TBM by regulating the posture of the TBM tunneling direction and calculating the stroke difference of the propulsion cylinder, realizes safe and efficient tunneling of the TBM, provides guidance and basis for the posture control of the tunneling direction of the TBM construction, and is suitable for tunnels with large diameters and small turning radiuses TBM tunneling construction.

Description

Control method of driving direction and attitude of TBM in large-diameter and small-turn tunnels

technical field

The invention belongs to the technical field of shield tunneling, and in particular relates to a method for controlling the posture of a TBM driving direction in a large-diameter and small-turn tunnel.

Background technique

As the most advanced large-scale equipment in current underground engineering construction, TBM integrates multiple processes such as excavation, slag removal and support, and can realize tunnel construction in one step, which has the advantages of high efficiency, safety and high economic benefits. TBM is also more and more widely used in the construction of railways, water conservancy, hydropower, subways, mines and other tunnels in my country. When using the TBM construction method to construct a tunnel, the tunneling direction of the TBM needs to be regulated according to the tunnel design axis, and the TBM tunneling route should be controlled within the deviation range of the tunnel design axis. This plays a vital role in ensuring the quality of tunnel construction.

When TBM is excavating in a straight section or a section with a large turning radius, its excavation posture is relatively easy to control, and construction can be carried out accurately according to the tunnel design axis. However, with more and more requirements for tunnel construction and more and more engineering uses of tunnels, the construction of small turning radius (turning radius < 10 times the tunnel diameter) has also begun to appear in tunnel construction. However, the minimum turning radius that conventional TBMs with open main girders can adapt to is generally not less than 40 times the tunnel diameter, which is difficult to meet the construction requirements of tunnels with small turning radii.

For those skilled in the art, how to control the tunneling direction and posture of the TBM so that it can meet the tunnel design requirements in the construction of tunnels with small turning radius and realize fast, accurate and safe construction is an urgent technical problem to be solved by those skilled in the art.

Contents of the invention

The purpose of the present invention is to provide a method for controlling the driving direction and posture of a TBM in a large-diameter and small-turn tunnel, aiming at solving the technical problem of how to control the driving direction and posture of a new type of open TBM in the construction of a tunnel with a small turning radius in the above-mentioned prior art.

In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is:

A method for controlling the direction and posture of a TBM with a large diameter and small turn, the TBM is a new type of open TBM, comprising the following steps:

S1. When the distance between the TBM and the turning radius cut-in point is greater than the length of the main body of the TBM, determine the position and attitude of the TBM in the curved tunnel;

S2. When the distance from the TBM to the turning radius cut-in point is equal to the length of the main body of the TBM, the positions of the front shield and cutter head of the TBM are adjusted so that they start to excavate in the direction of the inward bend of the turning section;

S3. When the cut-in point of the TBM distance from the turning section is half the length of the TBM main engine, adjust the attitude of the equipment bridge by adjusting the drag cylinder between the TBM support shield and the equipment bridge, so that it can maintain the turning attitude in advance;

S4. When the front shield and cutter head of the TBM just enter the turning section, adjust the tunneling direction of the TBM so that the tunneling axis of the TBM begins to gradually fit to the design axis of the curved tunnel;

S5. During the tunneling process of the TBM, adjust the tunneling parameters of the TBM and precisely locate the posture of the TBM.

Preferably, in step S1, the pose of the TBM is determined through the guidance visual recognition system on the TBM and the attitude of the TBM measured on site. The guidance visual recognition system includes a total station, a rearview prism, and a laser target supporting the tail of the shield. , support the camera in front of the shield and the MARK light behind the shield.

Preferably, in step S2, the position of the TBM front shield and the cutter head is regulated by adjusting the pressure values of the propulsion cylinders in the upper, lower, left and right four bit areas of the TBM, and by controlling the left and right supports on the support shield The elongation of the boots controls the position and attitude of the support shield so that it starts to dig in the direction of the inward bend of the turning section.

Preferably, in step S2, the TBM starts to excavate toward the inward bend direction of the curved tunnel turning section, and as the TBM advances forward, the TBM excavation axis and the tunnel design axis gradually deviate, and the TBM gradually deviates toward the inner bend of the turning section; when the TBM reaches the turning When the section entry point is reached, the deviation between the TBM excavation axis and the tunnel design axis reaches the maximum and does not exceed the maximum allowable deviation of the tunnel design axis.

Preferably, in step S3, the attitude of the equipment bridge is adjusted by adjusting the dragging cylinders between the TBM support shield and the equipment bridge. , to realize the attitude adjustment of the equipment bridge.

Preferably, in step S4, the construction operation mode of "short footage, frequent step change and direction adjustment" is adopted, and the tunneling direction of the TBM is adjusted at the same time; just after the TBM enters the turning section, the tunneling axis of the TBM begins to gradually approach the tunnel design axis. After the whole has completely entered the turning section, the TBM excavation axis is consistent with the tunnel design axis.

Preferably, the adjustment of the TBM excavation parameters in step S5 includes reducing the excavation thrust, reducing the torque of the cutter head, slowing down the excavation speed, and locating the pose of the TBM through a total station and a rearview prism.

Preferably, the calculation of the stroke difference of the propulsion cylinder in the TBM in step S2 is divided into the following two situations: the first situation is the state where the TBM is excavating from the transition section from the straight section to the curved section, and the second situation is that the TBM completely enters the curve State of excavation in the section.

Preferably, in the first case, the TBM excavates from the transition section from the straight section to the curved section, and the step of calculating the stroke difference of the propulsion cylinder includes:

Use the formula (1) to determine the number of excavation steps required by the TBM in the transition section:

（1）

(1)

为支撑靴中心到前盾支撑点的距离，/>

为前盾中心到前盾支撑点的距离，s为掘进距离，/>

函数表示不小于某个数的最大整数；Among them, N is the number of steps of TBM digging;

is the distance from the center of the support shoe to the support point of the front shield, />

is the distance from the center of the front shield to the support point of the front shield, s is the excavation distance, />

The function represents the largest integer not less than a certain number;

Under the condition that the turning radius is determined, formula (2) is used to determine the relationship between the cutter head excavation distance and the cutter head deflection angle:

（2）

(2)

Among them, α is the deflection angle of the cutter head, and R is the radius of the turning section;

According to the geometric relationship of the TBM during the excavation process, the stroke difference of the propulsion cylinder is determined for each excavation step.

Preferably, in the second case, formula (3) is used to determine the deflection angle of the cutter head and the support shoe in the initial state:

（3）

(3)

Among them, N is the sum of TBM digging steps in the first case;

Use the formula (4) to determine the relationship between the cutting distance of the cutter head and the deflection angle of the cutter head:

（4）

(4)

According to the geometric relationship of the TBM during the excavation process, the stroke difference of the propulsion cylinder for each step is determined.

The beneficial effect produced by adopting the above technical solution is: compared with the prior art, the present invention realizes more moderate excavation construction through the excavation route within the allowable deviation range of the tunnel axis when the new open TBM makes a small turn , so that the TBM can safely and efficiently excavate while meeting the requirements of the tunnel design axis; at the same time, by adjusting the turning posture of the TBM, the interference problem between the equipment is avoided, and the overall passing efficiency of the TBM is improved; by adjusting the stroke difference of the TBM propulsion cylinder Accurate calculation provides quantitative theoretical data guidance and basis for TBM tunneling direction attitude operation control. The invention is suitable for shield excavation construction of large diameter, small turning radius and multi-slope tunnels, and solves the problem that the tunneling axis exceeds the deviation range of the tunnel design axis when the TBM passes through the small turning radius and the interference problem between the structural parts of the TBM.

Description of drawings

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 1 is the construction flow chart of a kind of large-diameter small-turn tunnel TBM driving direction attitude control method provided by the present invention;

Fig. 2 is the structural representation of TBM in the embodiment of the present invention;

Fig. 3 is a schematic diagram of the distribution of the propulsion cylinders on the TBM in an embodiment of the present invention;

Fig. 4 is a schematic diagram of the installation of the drag cylinder on the TBM in the embodiment of the present invention;

Figure 5 is a schematic diagram of the initial position of the TBM in the first case;

Fig. 6 is a schematic diagram of the position of the TBM after the first excavation, the excavation distance s of the front shield and the deflection angle α in the first case;

Fig. 7 is a schematic diagram of the position of the TBM tunneling to the nth step in the first case;

Fig. 8 is a schematic diagram of the TBM reaching the termination position in the first case, and the total deflection angle of the front shield is Nα;

Figure 9 is a schematic diagram of the TBM at the initial position in the second case, and the initial angle between the front shield and the support shield is Nα;

Fig. 10 is the schematic diagram when TBM drives forward under the second situation;

In the figure: 1 is the cutter head, 2 is the front shield, 3 is the propulsion cylinder, 4 is the support shield, 5 is the support shoe, 6 is the main beam, 7 is the drag cylinder, and 8 is the equipment bridge.

Detailed ways

The technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

At present, in order to meet the needs of tunnel construction with small turning radius, a new type of open TBM has been developed, as shown in Figure 2 and 3, including double shields (front shield 2 and support shield 4), partition (group) Propulsion cylinder 3, support shoe and support shoe cylinder, torque cylinder and torque arm (not shown in the figure), the TBM main engine adopts a double shield structure with parallel propulsion cylinder 3 and torque cylinder, and the main engine is equipped with anchor spray support.

The embodiment of the present invention provides a large-diameter small-turn tunnel TBM excavation direction attitude control method, the TBM is a new type of open TBM, the rear main girder 6 of the support shield 4 is connected with the equipment bridge 8 through the drag cylinder 7, as shown in Figure 4 Show. Using this method can provide precise control values for TBM attitude control, ensuring accurate and rapid excavation of TBM along the tunnel design axis. The construction process is shown in Figure 1, and specifically includes the following steps:

S1. When the distance between the TBM and the cutting point of the turning radius is greater than the length of the main body of the TBM, the position and accurate posture of the TBM in the curved tunnel can be determined by measuring the attitude of the TBM at this time through the guidance visual recognition system on the TBM and the on-site construction personnel. . Among them, the guiding visual recognition system includes a total station, a rearview prism, a laser target supporting the tail of the shield, a camera in front of the supporting shield, and a MARK light behind the front shield. Here, the diameter of the curved tunnel is ≥8m, and the radius R of the turning section is ≤300m.

Make the TBM start to excavate in the direction of the inward curve of the curve tunnel. As the TBM advances forward, the TBM excavation axis and the tunnel design axis gradually deviate, and the TBM gradually deviates towards the inward curve of the curve; when the TBM reaches the cut-in point of the curve, the TBM excavation The deviation between the axis and the tunnel design axis reaches the maximum and does not exceed the maximum allowable deviation of the tunnel design axis.

S2. When the distance from the TBM to the cutting point of the turning radius is equal to the length of the main body of the TBM, by adjusting the pressure value of the propulsion cylinder 3 in the upper, lower, left and right four bit areas of the TBM, the TBM front shield 2 and cutter head 1 The position is regulated, and by controlling the elongation of the left and right support boots 5 on the support shield 4, the position posture of the support shield 4 is controlled, so that it begins to excavate in the direction of the inward bend of the turning section. Here, the length of the host refers to the length from the cutter head to the tail of the supporting shield. Wherein, the propulsion oil cylinders in the upper, lower, left and right four position areas of the TBM are parallel to each other.

S3. When the cut-in point of the turning section from the TBM is about half the length of the main engine of the TBM, adjust the attitude of the equipment bridge 8 by adjusting the drag cylinder 7 between the TBM support shield 4 and the equipment bridge 8, so that it can maintain the turning attitude in advance . As shown in FIG. 4 , there are two dragging cylinders 7 arranged side by side. By adjusting the stroke difference between the two dragging cylinders 7 , the posture adjustment of the equipment bridge 8 is realized.

S4. When the TBM front shield 2 and cutter head 1 just enter the turning section, adopt the construction operation method of "short footage, frequent step change and direction adjustment", and adjust the tunneling direction of the TBM at the same time, so that the tunneling axis of the TBM begins to gradually move towards the design axis of the curved tunnel fit. Just after the TBM entered the turning section, the TBM excavation axis began to gradually approach the tunnel design axis. After the TBM equipment completely entered the turning section, the TBM excavation axis was consistent with the tunnel design axis.

S5. During TBM turning tunneling, adjust TBM tunneling parameters, including reducing tunneling thrust, reducing cutter head torque, slowing down tunneling speed, and slowly advancing into the turning section while ensuring that the cutter and posture are normal; pay close attention to internal and external telescopic protection The coordination of the shield can change the posture of the inner shield by controlling the extension of the telescopic cylinder to avoid interference. The adjustment amount of TBM tunneling parameters depends on the actual construction situation. At the same time, the on-site surveyors change the positions of the total station and the rearview prism in time to achieve precise positioning of the TBM's pose.

In the embodiment shown in FIG. 2 , the multiple propulsion cylinders of the TBM are divided into four groups, ABCD, and all the propulsion cylinders 3 of the TBM are kept parallel during the above-mentioned turning process.

In step S2, during specific implementation, the calculation of the stroke difference of the propulsion cylinder in the TBM is divided into the following two situations: the first situation is the state where the TBM is excavating from the transition section from the straight section to the curved section, and the second situation is that the TBM Fully enter the state of excavation in the curved segment.

In the first case, the TBM excavates from the transition section from the straight section to the curved section, and the calculation steps of the stroke difference of the propulsion cylinder include:

Use the formula (1) to determine the number of excavation steps required by the TBM in the transition section:

（1）

(1)

为支撑靴5中心到前盾2支撑点的距离，/>

为前盾2中心到前盾支撑点的距离，s为掘进距离，/>

函数表示不小于某个数的最大整数；Among them, N is the number of steps of TBM digging;

is the distance from the center of the support boot 5 to the support point of the front shield 2, />

is the distance from the center of the front shield 2 to the support point of the front shield, s is the excavation distance, />

The function represents the largest integer not less than a certain number;

Under the condition that the turning radius is determined, formula (2) is used to determine the relationship between the excavation distance of cutter head 1 and the deflection angle α of cutter head:

（2）

(2)

Among them, α is the deflection angle of the cutter head, and R is the radius of the turning section;

According to the geometric relationship of the TBM during the excavation process, the stroke difference of the propulsion cylinder is determined for each excavation step.

In the second case, use the formula (3) to determine the deflection angle of the cutterhead 1 and the shoe 5 in the initial state:

（3）

(3)

Among them, N is the sum of TBM digging steps in the first case;

Use formula (4) to determine the relationship between the excavation distance of cutter head 1 and the deflection angle α of cutter head:

（4）

(4)

According to the geometric relationship of the TBM during the excavation process, the stroke difference of the propulsion cylinder for each step is determined.

Adopting the above scheme can precisely control the direction and posture of TBM excavation. When applying the new type of open TBM, this new type of TBM is used in the excavation of small turns (turning radius ≤ 300m) in large-diameter tunnels (tunnel diameter ≥ 8m), using the method provided by the present invention for planning A TBM excavation route was developed, which achieved a more moderate excavation construction within the allowable deviation range of the tunnel axis, enabling the TBM to safely and efficiently excavate while meeting the requirements of the tunnel design axis. At the same time, all propulsion cylinders are kept in parallel. By adjusting the stroke difference of the two drag cylinders, the posture of the equipment bridge is changed to guide the forward direction of the supporting trolley, avoiding the interference between equipment and improving the overall passing efficiency of the TBM. In addition, the precise calculation of the stroke difference of the propulsion cylinder of the TBM during the turning tunneling is realized, which provides quantitative theoretical data guidance and basis for the attitude operation control of the TBM tunneling direction.

The present invention will be further described below in conjunction with specific embodiments. The first embodiment takes the TBM ultra-small turning construction of the approach traffic tunnel and ventilation tunnel of a certain pumped storage power station as an example. This project adopts a new type of TBM with a diameter of 9.53m for cavern development. Excavation and initial support, the maximum longitudinal slope of the traffic tunnel is 6.6%, the plane turning radius is all 100m, and the longitudinal slope of the turning section is 3%; the plane turning radius of the ventilation tunnel is 90m, and the turning radius of the remaining tunnel sections is 100m, 2.44% is adopted; the length of the underground powerhouse section is 164m, and the maximum longitudinal slope is 9.02%. The tunnel design axis requires a horizontal deviation range of ±100mm and a vertical deviation range of ±80mm. When the traditional TBM type is faced with a tunnel with a large diameter of 9.53m and a plane turning radius of 90m, due to its structural characteristics, it cannot realize the excavation with the minimum turning radius. The new TBM adopted according to the engineering situation is a new open TBM, and the structure of the new TBM is shown in Figure 2. The new type of TBM uses the propulsion cylinder to provide propulsion for the cutter head, and adjusts the position and posture of the TBM cutter head by adjusting the cylinder extension of the four partitions of the upper, lower, left, and right sides of the propulsion cylinder as shown in Figure 3, and the support shoes on the support shield are tightened The cave wall bears the reverse thrust of the cutter head, and the position and posture of the TBM support shield can be adjusted by adjusting the extension of the left and right support shoes. The structure of the new TBM enables the TBM to carry out construction with a turning radius of 90m. However, for the construction of ultra-small turning radius for this type of large-diameter new TBM for the first time, there is no corresponding construction control technology method in the prior art. The TBM in the construction of the turning section controls the attitude of the tunneling direction, and the specific steps are as follows:

S1. When the distance between the TBM and the cutting point of the turning radius is greater than the length of the main body of the TBM, the automatic guidance system on the TBM and the on-site measurement construction personnel measure the attitude of the TBM at this time to determine the exact attitude and position of the TBM in the tunnel.

Specifically, through the guidance + visual recognition system composed of the total station, the rear-view prism, the laser target supporting the tail of the shield, the camera in front of the shield and the MARK light behind the front shield, it is determined that the current TBM is in the tunnel The position of the current TBM mainframe can also be determined. The guidance system will display the horizontal deviation and vertical deviation of the front, middle front, middle and rear parts. The front and middle front represent the space posture of the TBM front shield, and the middle and rear represent the space posture of the TBM support shield. It is understood as the spatial attitude of the TBM propulsion cylinder. When the distance between the TBM and the cutting point of the turning radius is greater than the length of the main body of the TBM, according to the known space attitude of the front shield and the support shield, adjust the elongation of the propulsion cylinders in the four partitions of the upper, lower, left, and right sides, so that the movement posture of the front shield and the support shield trend on the same axis.

S2. When the distance from the TBM to the cutting point of the turning radius is equal to the length of the TBM main engine, adjust the position of the TBM front shield and cutter head by adjusting the pressure value of the propulsion cylinder in the four bit areas of the TBM up, down, left and right. Control, and control the position and posture of the support shield by controlling the elongation of the left and right support boots on the support shield. Make the TBM start to excavate towards the inward bending direction of the turning section.

Specifically, the position of the entry point in the turning section is determined according to the length of the TBM main engine, which is consistent with the length of the main engine, and provides conditions for the design of the tunneling route and the adjustment of the posture of the TBM main engine. As shown in Figure 3, the stroke difference of the propulsion cylinder is formed by adjusting the elongation of the propulsion cylinder in the four partitions of up, down, left and right, so that the cutter head and the front shield can face up, down, left and right in four directions Conduct deflection tunneling. Taking a right turn as an example, in the absence of a transitional curve, when the distance from the entry point of the turning section is the length of the TBM main engine, within the allowable range of the horizontal deviation of the design axis of the project (horizontal deviation ±100mm), correct the deviation to the right by 10mm per meter , so that the main engine enters the right turn trend in advance. After the circular curve cuts in, the horizontal posture is at +100mm.

S3. When the distance from the TBM to the entry point of the turning section is about half the length of the TBM main engine, start to adjust the attitude of the equipment bridge through the drag cylinder between the TBM support shield and the equipment bridge, so that it can maintain the turning attitude in advance.

Specifically, 5m before the equipment bridge enters the R90 and R100 circular curve entry points, because the equipment bridge is relatively wide overall, or when there is a steel arch frame at the current position, when entering a turn, the entry point has a large arc, which is easy to be directly connected with the surrounding rock. Interference occurs, so when entering a turn, it is necessary to lay the trolley track according to the posture of the support shield. In the case of ensuring that the edge of the track and the trolley wheels do not interfere, as shown in Figure 4, shield a dragging cylinder as much as possible. The other dragging oil cylinder is pulled apart in advance to form a difference, so that the equipment bridge can keep the turning posture in advance, so as to facilitate the passing of the equipment bridge.

S4. When the TBM front shield and cutter head just enter the turning section, adopt the construction operation idea of "short footage, frequent step change and direction adjustment". At the same time, the tunneling direction of the TBM is adjusted so that the TBM tunneling axis gradually fits to the tunnel design axis.

Specifically, each excavation cycle of the TBM is changed from the original 1.5m to 0.5m. After the excavation is completed, the TBM will change steps and adjust the direction to continue the excavation. Also take a right turn as an example, continue to step S2 and control the horizontal attitude of the TBM cutterhead to correct the deviation by 10mm to the left per meter until it reaches 0 in combination with the current turning radius of the tunnel circular curve and the horizontal attitude of the TBM. In this way, the turning radius of 90m can be changed to a turning radius of 90.461m, the arc of the right-turn entry point can be slowed down, and the interference between the host machines can be reduced. put one's oar in.

S5. During the TBM turning tunneling process, adjust the TBM tunneling parameters, and slowly advance into the turning section under the condition that the tool and posture are normal. Pay close attention to the coordination of the inner and outer telescopic shields, and change the posture of the inner shield by controlling the extension of the telescopic cylinder to avoid interference. At the same time, on-site surveyors change the positions of the total station and the rearview prism in time to achieve precise positioning of the TBM pose.

Specifically, when entering the turning section, because the shield does not fully enter the turning section, it will make it difficult to control the attitude of the cutterhead. At this time, it is necessary to reduce the thrust of the excavation, reduce the torque of the cutterhead, and slow down the excavation speed. Proceed slowly as normal. Combined with the situation of this project, when the TBM is transferred from the straight section to the 90m turning section, the excavation thrust is reduced from 20800kN-22300kN to 11800kN-18200kN, and the cutterhead torque is reduced from 1800kN m to 2700kN m to 1400kN m to 2300kN m . The excavation of the simultaneous turning section is carried out in the way of high speed and small penetration. This operation is to reduce the force difference of a single cutter body in different operating directions, so as to reduce the resistance of the cutter as much as possible, so as to protect the The role of knives.

More specifically, add edge hobs and gage cutter pads or replace large-size cutters in ultra-small turning sections under appropriate circumstances to increase the excavation hole diameter, reduce the phenomenon of main engine jamming, improve tunneling efficiency, and make the TBM turn smoothly. However, when using the overbreak device, strictly control the amount of overbreak; in the case of not interfering with the surrounding rock mass, properly manually extend the left cylinder of the telescopic inner shield during the step change process, and pay attention to the cooperation of the inner and outer telescopic shields, and the telescopic outer shield. The shield is fixedly connected to the front shield. As the posture of the front shield changes, the posture of the telescopic inner shield needs to be changed by adjusting the telescopic oil cylinder so that it cooperates with the telescopic outer shield to keep in line with the turning trend; increase the frequency of construction measurement and increase the interval between stations The number is reduced from the interval of 75m in the straight section to the interval of 10m in the turning section to ensure the measurement accuracy of the TBM during the construction of the turning section.

In addition to the above-mentioned attitude control method for the TBM heading direction, step S2 also provides a calculation method for the stroke difference of the propulsion cylinder, which provides quantitative data theoretical support for the attitude control of the TBM heading direction. It specifically includes the calculation method of the TBM in the following two cases. The first case is the state where the TBM is excavating in the transition section from the straight line to the curved section, and the second case is the state where the TBM completely enters the curved section for excavation.

Second embodiment:

This embodiment is to illustrate the calculation of the stroke difference of the propulsion cylinder in the first case. When the TBM is in the transition stage from the straight section to the curved section, in order to ensure that it advances according to the tunnel design axis, the center of the support shield and the front shield under ideal conditions The support points need to always be on the tunnel design axis.

It should be noted that the initial moment of the first case is the moment when the front shield support point reaches the tangent point of the straight line segment and the curved line segment, and the end time is the time when the support shoe reaches the tangent point of the straight line segment and the curved line segment.

For the calculation of the propulsion cylinder difference in the first case, the following turning excavation steps need to be understood:

S1 and Fig. 6 are the positions of the TBM at the initial moment after it begins to excavate one stroke forward. The dotted line part is the position of the front shield at the initial moment, and the solid line part is the position of the front shield after one stroke of excavation. The excavation distance of the front shield is s, and the deflection angle is α.

S2. Then the TBM support shield support shoes are retracted, reset and then tighten the cave wall, and the TBM front shield continues to dig forward, which is consistent with step S1.

S3. Finally, repeating steps S1 and S2 until the support shoe reaches the tangent point between the straight line and the curved line, it is considered that the excavation of the transition section is completed, as shown in FIG. 8 .

Specifically, as shown in Figure 5 and Figure 6, it is necessary to determine the number of excavation steps N required by the TBM in the first case according to the excavation distance s, and the number of steps N can be obtained by the following expression:

为支撑靴中心到支撑点的距离，/>

为前盾中心到支撑点的距离，s为掘进距离，/>

函数表示不小于某个数的最大整数。in,

is the distance from the center of the support shoe to the support point, />

is the distance from the center of the front shield to the support point, s is the excavation distance, />

A function representing the largest integer not less than a certain number.

Specifically, in the case that the turning radius R is determined, the deflection angle α after the cutter head is excavated s is determined. According to the geometric relationship in Figure 6, the following expression can be obtained:

），根据图7所示，可以得出刀盘总的偏转角度/>

，同时根据辅助线和几何关系得出下列计算公式：When the TBM steps to the nth step in the first case (

), as shown in Figure 7, the total deflection angle of the cutter head can be obtained />

, and get the following calculation formula according to the auxiliary line and geometric relationship:

为支撑靴中心到直线段和曲线段相切点的距离；d为推进油缸分布节圆直径；/>

为支撑靴中心到支撑盾前面板的距离；/>

为内侧推进油缸的总长度；/>

为外侧推进油缸的总长度。in,

is the distance from the center of the support shoe to the tangent point of the straight line segment and the curve segment; d is the pitch circle diameter of the propulsion cylinder distribution; />

is the distance from the center of the support shoe to the front panel of the support shield; />

is the total length of the inside propulsion cylinder; />

is the total length of the outboard propulsion cylinder.

According to the calculation of the above formula, it can be obtained that the stroke difference between the inner and outer sides of the propulsion cylinder when the cutter head digs one step from the initial moment in a tunnel with a turning radius of TBM:

Third embodiment:

This example is to illustrate the calculation of the stroke difference of the propulsion cylinder in the second case. It is similar to the transition stage of the TBM from the straight section to the curved section. In order to ensure that the tunnel advances according to the tunnel design axis, the center of the support shield and the front shield under ideal conditions The support points need to always be on the tunnel design axis.

It should be noted that, in the second case, the excavation process is a repeating process because the excavation is performed in a pure curve, and there is no initial moment and end moment.

For the calculation of the stroke difference of the propulsion cylinder in the second case, it is necessary to understand the following turning excavation steps:

S1. As shown in FIG. 9 , in the initial state, the cutterhead and the support shoe form a certain angle δ.

S2. As shown in FIG. 10 , the position where the cutterhead starts to advance one stroke forward. The dotted line part is the position of the front shield at the initial moment, and the solid line part is the position of the front shield after one stroke of excavation. The excavation distance of the front shield is s, and the deflection angle is α as in the first embodiment.

S3. Then the TBM support shield support shoes are retracted, reset and then tighten the cave wall, and the TBM front shield continues to dig forward, which is consistent with step S2.

S4. Finally, repeat steps S2 and S3 until the excavation of the curved section is completed.

The following calculation idea is consistent with the calculation idea of the second embodiment.

When tunneling into the turning section, there is a certain angle δ between the cutter head and the support shoe in the initial state, which is the sum of the accumulated angles in the first case, namely:

Wherein, N is the total number of excavation steps in the second embodiment.

After the cutter head is driven forward for a stroke, as shown in Figure 10, the following calculation formula can be obtained according to the auxiliary line and geometric relationship:

刀盘向前掘进s后与支撑靴的角度；d为推进油缸分布节圆直径；/>

为支撑靴中心到支撑盾前面板的距离；/>

为内侧推进油缸的总长度；/>

为外侧推进油缸的总长度。in,

The angle between the cutter head and the support shoe after the cutter head is driven forward by s; d is the pitch circle diameter of the propulsion cylinder distribution; />

is the distance from the center of the support shoe to the front panel of the support shield; />

is the total length of the inside propulsion cylinder; />

is the total length of the outboard propulsion cylinder.

According to the calculation of the above formula, it can be obtained that when the TBM is excavating in a pure curve section, the stroke difference between the inner and outer sides of the propulsion cylinder when the cutter head is excavating one step:

To sum up, the TBM driving direction attitude control method provided by the present invention can enable the TBM to drive along a relatively gentle route within the allowable deviation range of the tunnel axis, so that the TBM can realize rapid tunneling while meeting the requirements of the tunnel design axis. , Safe excavation, improve the overall passing efficiency of TBM. At the same time, by calculating the stroke difference of the propulsion cylinder, it provides accurate control values for the attitude control of the TBM's heading direction, avoids the interference problem between equipment, and provides quantitative theoretical data guidance and basis for the attitude operation control of the TBM heading direction.

In the above description, many specific details have been set forth in order to fully understand the present invention, but the present invention can also be implemented in other ways that are different from those described here, and those skilled in the art can do without departing from the connotation of the present invention. By analogy, the present invention is therefore not limited to the specific embodiments disclosed above.

Claims (10)

1. A large-diameter and small-turn tunnel TBM driving direction attitude control method is characterized in that the TBM is a novel open type TBM, comprising the following steps: S1. When the distance between the TBM and the cut-in point of the turning radius of the curved tunnel is greater than the length of the main body of the TBM, determine the position and attitude of the TBM in the curved tunnel; S2. When the distance from the TBM to the turning radius cut-in point is equal to the length of the main body of the TBM, the positions of the front shield and cutter head of the TBM are adjusted so that they start to excavate in the direction of the inward bend of the turning section; S3. When the distance from the TBM to the entry point of the turning section is half the length of the TBM main engine, adjust the TBM to keep the turning attitude in advance; S4. When the front shield and cutter head of the TBM just enter the turning section, adjust the tunneling direction of the TBM so that the tunneling axis of the TBM begins to gradually fit to the design axis of the curved tunnel; S5. During the tunneling process of the TBM, adjusting the tunneling parameters of the TBM and locating the pose of the TBM. 2. The TBM driving direction posture control method for large-diameter and small-turn tunnels according to claim 1, characterized in that: in step S1, the posture of the TBM is determined by the orientation visual recognition system on the TBM and the posture of the TBM being measured on-site, The guidance visual recognition system includes a total station, a rearview prism, a laser target supporting the tail of the shield, a camera in front of the shield supporting it, and a MARK light behind the front shield. 3. The method for adjusting the direction and attitude of TBM in large-diameter and small-turn tunnels according to claim 1, characterized in that: in step S2, by adjusting the pressure values of the propulsion cylinders in the upper, lower, left and right four bit areas of the TBM , adjust the positions of the TBM front shield and the cutter head, and control the position and posture of the support shield by controlling the elongation of the left and right support shoes on the support shield, so that it starts to excavate in the direction of the inward bend of the turning section. 4. The method for controlling the direction and attitude of the TBM in the large-diameter and small-turn tunnel according to claim 1, characterized in that: in step S2, the TBM is started to excavate in the direction of the inward bend of the curve tunnel, and as the TBM advances forward, the TBM excavates The axis and the tunnel design axis deviate gradually, and the TBM gradually deviates toward the inward bend of the turning section; when the TBM reaches the entry point of the turning section, the deviation between the TBM excavation axis and the tunnel design axis reaches the maximum, and does not exceed the maximum allowable deviation of the tunnel design axis. 5. The method for regulating and controlling the posture of the TBM driving direction in a large-diameter and small-turn tunnel according to claim 1, wherein in step S3, the posture of the equipment bridge is adjusted by adjusting the dragging cylinder between the TBM support shield and the equipment bridge, so that There are two pulling oil cylinders arranged side by side, and the attitude adjustment of the equipment bridge is realized by adjusting the stroke difference of the two pulling oil cylinders. 6. The method for controlling the attitude and posture of TBM tunneling in large-diameter and small-turn tunnels according to claim 1, characterized in that: in step S4, the construction operation mode of "short footage, frequent step change" is adopted, and the tunneling direction of TBM is adjusted at the same time ; Just after the TBM enters the turning section, the TBM excavation axis begins to gradually approach the tunnel design axis, and after the TBM equipment as a whole enters the turning section, the TBM excavation axis is consistent with the tunnel design axis. 7. The method for regulating and controlling the direction and posture of TBM tunneling with large diameter and small turn according to claim 1, characterized in that: the adjustment of TBM tunneling parameters in step S5 includes reducing tunneling thrust, reducing cutter head torque, and slowing down tunneling speed. The total station and the rearview prism determine the pose of the TBM. 8. according to claim 1, the large-diameter and small-turn tunnel TBM driving direction posture control method is characterized in that: in step S2, the calculation of the stroke difference of the propulsion cylinder in the TBM is divided into the following two cases: the first case is that the TBM starts from The state in which excavation is carried out in the transition section from the straight section to the curved section, and the second case is the state in which the TBM completely enters the curved section for excavation. 9. The method for controlling the direction and attitude of TBM in large-diameter and small-turn tunnels according to claim 8, characterized in that: in the first case, the TBM excavates from the transition section from the straight section to the curved section, and the stroke difference of the propulsion cylinder is The calculation steps are as follows: Use the following formula (1) to determine the number of excavation steps required by the TBM in the transition section:

(1) Among them, N is the number of steps of TBM digging;

is the distance from the center of the support shoe to the support point of the front shield, />

is the distance from the center of the front shield to the support point of the front shield, s is the excavation distance, />

The function represents the largest integer not less than a certain number; Under the condition that the turning radius is determined, use the following formula (2) to determine the relationship between the cutting distance of the cutterhead and the deflection angle of the cutterhead:

(2) Among them, α is the deflection angle of the cutter head, and R is the radius of the turning section; According to the geometric relationship of the TBM during the excavation process, the stroke difference of the propulsion cylinder is determined for each excavation step. 10. The method for controlling the attitude and attitude of TBM excavation direction in large-diameter and small-turn tunnels according to claim 8, characterized in that in the second case, the following formula (3) is used to determine the deflection angle of the cutter head and the support shoe in the initial state:

(3) Among them, N is the sum of TBM digging steps in the first case; Use the following formula (4) to determine the relationship between the cutting distance of the cutter head and the deflection angle of the cutter head:

(4) According to the geometric relationship of the TBM during the excavation process, the stroke difference of the propulsion cylinder for each step is determined.

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