Balanced distribution method for partition thrusts and partition oil pressures during intelligent tunneling process of shield tunneling machine

Abstract

A balanced distribution method for partition thrusts and partition oil pressures during an intelligent tunneling process of a shield tunneling machine. The method comprises: for a shield tunneling machine in which equivalent force-bearing points of partitions are distributed along a circumference at equal intervals in an installation plane, by using an obliquely-truncated cylinder mathematical model, establishing a partition thrust / oil pressure constraint formula under the condition that partition thrust / oil pressure vector endpoints are coplanar; solving an unknown quantity in the constraint formula, so as to obtain a balanced distribution result of partition thrusts or partition oil pressures; and finally, by means of a conversion relationship, correspondingly obtaining the balanced distribution result of the partition oil pressures or the partition thrusts. Thus, the oil pressure and thrust in each partition meet the requirements of a target total thrust and a target correction-deviation moment; moreover, the distribution balance of the partition thrusts and the partition oil pressures is ensured, and bending moments of segment pieces on the boundaries of the partitions are reduced, thereby reducing damage to the segment pieces, and facilitating the protection of segment rings during tunneling construction. The distribution process is accurate and efficient, and provides a technical foundation for automatic / intelligent control over the attitude of a shield tunneling machine.

Description

Method for balanced distribution of zoned thrust and oil pressure during intelligent tunneling of shield machine Technical Field

[0001] The present invention relates to the technical field of shield machine control, and in particular to a method for balancing thrust and oil pressure during intelligent tunneling of a shield machine. Background Art

[0002] A shield machine (TBM) is a tunnel boring machine that uses the shield method. Its basic operating principle is that a cylindrical steel assembly advances along the tunnel axis, excavating the soil and laying supporting segments as it advances. Thrust cylinders are typically evenly distributed around the circumference of the shield. The grippers at the top of the thrust cylinder piston rods bear against the end faces of the pipe rings, slowly extending the piston rods to reverse the direction of movement. In more basic and common shield machine designs, such as those with synchronous tunneling capabilities, the thrust system typically includes multiple, independently pressure-adjustable zones spaced evenly around the circumference, with each zone containing an equal number of cylinder groups. Depending on project requirements, single or multiple adjacent thrust cylinder groups are connected in parallel as a zone, with the same valve block controlling the oil pressure. This ensures that all cylinder groups within the same zone have the same thrust / pressure. Thrust cylinders are typically grouped in pairs or singly, and all cylinders within a group have the same thrust.

[0003] In recent years, shield machine equipment and construction methods have been developing towards automation and intelligence. A crucial aspect is the automatic control of the shield machine's excavation posture. To adjust the shield machine's posture to the target posture or planned line, the shield machine's posture can be corrected by adjusting the zoned oil pressure / thrust of the shield machine's propulsion cylinders, adjusting the intensity and direction of the corrective torque, and thus achieving the purpose of correcting the shield machine's posture. However, under the conditions of the same total thrust and corrective torque, there are a large number of possible combinations of zoned oil pressure / thrust values. In engineering practice, drivers usually control the system based on their experience and habits. Different drivers have different operating methods, resulting in significant differences in the distribution of zoned oil pressure / thrust values ​​under the same conditions. This cannot provide a useful reference for the development of automatic / intelligent control technology for shield machine posture.

[0004] In addition, the distribution of oil pressure and thrust also needs to take into account the requirement for balance. The irregular zone oil pressure / thrust distribution method is shown in Figure 1(a), and the balanced oil pressure / thrust distribution is shown in Figure 1(b). Based on actual construction conditions, the industry generally believes that the smaller the difference in oil pressure / thrust between adjacent zones, the smaller the bending torque on the zone boundary segments, which can reduce segment damage. Therefore, under the premise of the same total thrust and corrective torque, the more balanced the oil pressure / thrust in each zone, the better. In other words, the distribution result is optimal if the gradient of the zone oil pressure / thrust changes in the direction of the target corrective torque is consistent.

[0005] A shield machine has three degrees of freedom: pitch, yaw, and fore-aft translation. However, the number of propulsion cylinders is far greater than three, leading to the problem of hydraulic cylinder overdrive. To achieve the shield machine's kinematic mechanics, it is necessary to coordinate and distribute the redundant propulsion cylinder thrust or oil pressure. This problem is similar to the redundancy problems encountered in aviation, navigation, automotive, and other fields, and is called the control allocation problem. The main algorithms currently used to solve the control allocation problem include:

[0006] (1) Explicit combination method: The explicit combination method uses a pre-designed combination method to produce a single control effect by coordinating multiple actuator structures. This method is easy to implement in engineering and is suitable for overdrive systems with obvious and limited combination methods. However, it cannot effectively handle constraints or optimize performance. When an actuator fails, the designed combination scheme will fail. It has no adaptive redistribution capability and is not suitable for systems with high redundancy.

[0007] This method requires pre-setting combinations to produce a single control action. However, the thrust of a shield machine is continuous within the feasible range, the corrective torque is also continuous within the range, and the corresponding thrust changes of each cylinder are also stable and continuous. Using the "explicit combination method" makes it difficult to design countless multi-cylinder thrust combinations within the feasible domain and achieve continuously changing target thrust and torque. Therefore, the explicit combination method is not suitable for solving the shield machine's zoned thrust distribution problem.

[0008] (2) Cascade Chain Method: Assuming the system's actuators are hierarchical, the core idea of ​​the cascade chain control allocation method is to quickly activate the next-level actuator to compensate for the required control amount if the previous-level actuator is saturated. The cascade chain control allocation algorithm has the advantages of simple engineering implementation, fast allocation speed, and reliable use, but it also has the problem of actuator saturation.

[0009] This method can easily lead to the thrust of the first actuator (thrust cylinder) reaching its limit, which is unacceptable in shield construction. Therefore, the cascade chain method is not suitable for solving the problem of shield machine thrust distribution.

[0010] (3) Direct Allocation Method: The direct allocation method was proposed by Duaham and is a geometric algorithm. In the process, given a control pseudo-instruction W, a suitable control input *R is obtained so that the pseudo-control input W*=LR* has the maximum amplitude in the W direction. Bodson transformed the direct allocation into the form of solving an optimization problem. Given ɑ and R*, he solved:

[0011] The direct allocation algorithm seeks to maximize the amplitude of the allocation result in the desired direction, and needs to use the optimization problem solving method to solve it, which is relatively cumbersome and not accurate enough.

[0012] (4) Generalized inverse allocation method: The generalized inverse control allocation algorithm introduces the minimum norm constraint, which can be expressed as The explicit solution of this formula is R = L + W, where L + =L T (LL T ) -1 is the pseudo-inverse matrix of L.

[0013] This method solves the movement amount of each actuator through generalized inverse, and pursues the minimum comprehensive output of the actuator. However, for the case of uneven distribution of the shield machine's propulsion cylinders - when the lever arms differ greatly, it can ensure that the distribution results meet the total thrust and torque requirements. However, the maximum oil pressure zone may be adjacent to the minimum oil pressure zone, and the distribution result cannot be guaranteed to be balanced, which affects the force on the pipe segments and poses potential risks.

[0014] In addition to the traditional control allocation algorithms listed above, there is also a fixed-point iterative algorithm proposed by Burken for solving weighted optimal control allocation problems. This algorithm is similar to the iterative algorithm of gradient search and has global convergence, but if an unreachable instruction is given, the algorithm may be slow. In addition, there are interior point algorithms for solving quadratic programming and effective set algorithms for solving small to medium-sized quadratic programming problems. Both interior point algorithms and effective set algorithms transform the control allocation problem into a quadratic programming problem, and their purpose is to solve the optimal solution that meets the objective function and constraints. Using quadratic programming to solve the control allocation problem generally seeks to minimize the objective function under the constraints. This processing method can achieve thrust distribution in each partition that meets the target total thrust and corrective torque, but it cannot guarantee a balanced distribution result.

[0015] Summary of the Invention

[0016] The present invention is made to solve the above problems, and its purpose is to provide a method for balancing thrust and oil pressure during the intelligent tunneling process of a shield machine.

[0017] To achieve the above objectives, the present invention provides the following technical solutions:

[0018] A method for balancing thrust and oil pressure distribution in a shield machine's intelligent tunneling process, wherein the shield machine's propulsion system includes a plurality of independently adjustable oil pressure zones with equivalent force points equally spaced along the circumference within an installation plane, each zone comprising the same number of oil cylinder groups, and the thrust and oil pressure vector directions of the zones are both perpendicular to the installation plane, comprising:

[0019] Step S1: Determine the number of zones n of the shield machine, the number of cylinder groups m in each zone, the proportional coefficient K between the thrust and oil pressure of a single cylinder group, and the radius R of the circle where the equivalent force points of each zone are located. Then, establish a spatial rectangular coordinate system O-xyz with the center of the circle as the origin, and then further determine the horizontal target correction torque M of all zones relative to the origin O. x , vertical target correction torque M y And the target total thrust F t ;

[0020] Step S2: Using the mathematical model of the oblique truncated cylinder, establish the partition thrust constraint formula under the condition that the end points of the thrust vectors of each partition are coplanar: Alternatively, the partition oil pressure constraint formula can be established under the condition that the end points of the oil pressure vectors of each partition are coplanar:

[0021] Where, F i is the partition thrust of the i-th partition, P i is the oil pressure of the ith partition, θ i is the central angle corresponding to the center of the i-th partition, α is the direction angle of the projection of the major semi-axis of the elliptical oblique section in the mathematical model of the oblique cylinder on the installation plane, tanβ1 represents the inclination of the target plane where the end point of the thrust vector of each partition is located, and tanβ2 represents the inclination of the target plane where the end point of the oil pressure vector of each partition is located;

[0022] Step S3: According to the horizontal target correction torque M x , vertical target correction torque M y Get the target correction torque Then, the corresponding relationship between the direction angle of the projection of the major axis of the elliptical oblique section in the mathematical model of the oblique cylinder on the installation plane and the direction angle of the target correction torque is obtained.

[0023] Step S4: Combined with the equal relationship that the sum of the thrust torques of each partition in the ɑ direction is equal to the target correction torque, that is, Get the partition thrust constraint formula Or the partition oil pressure constraint formula

[0024] Step S5: Substitute α and tanβ1 into the partition thrust constraint formula to obtain i Substitute the partition thrust calculation formula into the central angle θ corresponding to each partition i Calculate the partition thrust of n partitions and convert the partition thrust to obtain the corresponding partition oil pressure; or substitute α and tanβ2 into the partition oil pressure constraint formula to obtain the partition oil pressure constraint formula about θ iThe zone oil pressure calculation formula is substituted into the central angle θ corresponding to each zone. i Calculate the partition oil pressure of n partitions, convert the partition oil pressure to obtain the corresponding partition thrust, and finally obtain the shield machine partition thrust and oil pressure balanced distribution results.

[0025] Furthermore, in step S1, K=F max / P max , F max The oil pressure of a single group of cylinders reaches the maximum value P max The corresponding maximum thrust.

[0026] Furthermore, in step S1, the positive direction of the z-axis in the spatial rectangular coordinate system O-xyz is perpendicular to the installation plane from the origin O to the shield machine's excavation direction, the positive direction of the y-axis is from the origin O in the installation plane to the shield machine's zenith direction, and the x-axis direction is determined according to the right-hand rule.

[0027] Furthermore, step S2 includes the following sub-steps:

[0028] Step S2-1, the geometric constraints that the truncated cylinder generatrix length in the truncated cylinder mathematical model should comply with are mapped to the thrust vector distribution model of each partition, and it is derived that when the end points of the thrust vectors of each partition are coplanar, the thrust F of the i-th partition is i The constraints that must be satisfied are: i =F b +R·cos(θ i -α)·tanβ1,

[0029] Where, the reference thrust F b is a virtual vector that is consistent with the direction of the thrust vector of each partition, with its starting point located at the origin O and its end point located at the target plane where the end point of the thrust vector of each partition is located;

[0030] Step S2-2: The relationship between the length of the truncated cylinder axis segment in the truncated cylinder mathematical model and the sum of the lengths of n equally spaced generatrixes is mapped to the thrust vector distribution model of each partition to obtain the reference thrust F b =F t / n.

[0031] Furthermore, step S2 includes the following sub-steps:

[0032] Step S2-1', the geometric constraints that the truncated cylinder generatrix length in the truncated cylinder mathematical model should meet are mapped to the oil pressure vector distribution model of each partition, and it is deduced that when the end points of the oil pressure vectors of each partition are coplanar, the oil pressure P of the i-th partition is i The constraints that must be satisfied are: i =P b +R·cos(θ i-α)·tanβ2,

[0033] Where, the reference thrust P b is a virtual vector that is consistent with the direction of the oil pressure vector of each partition, with its starting point located at the origin O and its end point located at the target plane where the end point of the oil pressure vector of each partition is located;

[0034] Step S2-2', according to The conversion relationship is used to obtain the reference oil pressure

[0035] The present invention has the following beneficial effects:

[0036] 1. The method for balancing thrust and oil pressure in the shield machine intelligent tunneling process of the present invention rationally distributes the thrust or oil pressure of n zones in the shield machine propulsion system to meet the given target total thrust F. t , horizontal target correction torque M x And the vertical target correction torque M y At the same time, the thrust / oil pressure gradient of each partition after distribution is uniform, and the optimal distribution result is obtained, laying a technical foundation for automatic / intelligent control of the shield machine posture.

[0037] 2. The distribution results obtained by the method for balancing the thrust and oil pressure in the zone during the intelligent tunneling process of the shield machine of the present invention have a smaller difference in thrust / oil pressure between adjacent zones, which can effectively reduce the bending moment on the pipe segments at the junction of the zones, thereby reducing damage to the pipe segments and facilitating the protection of the pipe ring during tunneling construction.

[0038] 3. The method for zoning thrust and oil pressure balancing distribution during the intelligent tunneling process of the shield machine of the present invention accurately and efficiently obtains the optimal thrust and oil pressure distribution results through theoretical calculations. It is suitable for the full-cylinder tunneling scenario during synchronous tunneling of the shield machine, and can provide a basis for the thrust and oil pressure balancing distribution of the shield machine in actual construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG1 is a schematic diagram of partition thrust distribution in an embodiment of the present invention;

[0040] FIG2 is a schematic diagram of the zoning distribution of propulsion cylinders of a shield machine according to an embodiment of the present invention;

[0041] 3 is a flow chart of a method for balancing thrust and oil pressure during intelligent tunneling of a shield machine according to an embodiment of the present invention;

[0042] FIG4 is a schematic diagram of a mathematical model of a truncated cylinder in an embodiment of the present invention;

[0043] FIG5 is a simulation diagram of the spatial distribution of thrust vectors in an embodiment of the present invention;

[0044] FIG6 is a simulation diagram of thrust distribution effect in an embodiment of the present invention;

[0045] FIG7 is a simulation diagram of the oil pressure vector spatial distribution in an embodiment of the present invention;

[0046] FIG8 is a simulation diagram of the oil pressure distribution effect in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following embodiments and the accompanying drawings specifically illustrate the method for zoning thrust and oil pressure balancing during the intelligent tunneling process of the shield machine of the present invention.

[0048] <Example>

[0049] As shown in Figures 1 and 2, in this embodiment, the propulsion system of the shield machine includes a plurality of independently adjustable oil pressure partitions with equivalent force points equally spaced along the circumferential direction within the installation plane. Each partition is composed of the same number of cylinder groups, and the partition thrust and partition oil pressure directions are both perpendicular to the installation plane.

[0050] As shown in FIG3 , the method for balancing thrust and oil pressure by zones during intelligent tunneling of a shield machine according to this embodiment includes the following steps:

[0051] Step S1: Determine the number of zones n of the shield machine, the number of cylinder groups m in each zone, the proportional coefficient K between the thrust and oil pressure of a single cylinder group, and the radius R of the circle where the equivalent force points of each zone are located. Then, establish a spatial rectangular coordinate system O-xyz with the center of the circle as the origin, and then further determine the horizontal target correction torque M of all zones relative to the origin O. x , vertical target correction torque M y And the target total thrust F t ;

[0052] Step S2: Using the mathematical model of the oblique truncated cylinder, establish the partition thrust constraint formula under the condition that the end points of the thrust vectors of each partition are coplanar: Alternatively, the partition oil pressure constraint formula can be established under the condition that the end points of the oil pressure vectors of each partition are coplanar:

[0053] Where, F i is the partition thrust of the i-th partition, P i is the oil pressure of the ith partition, θ i is the central angle corresponding to the center of the i-th partition (used to indicate the position of the equivalent force point of the partition, which can also be understood as the phase angle), α is the direction angle of the projection of the major semi-axis of the elliptical oblique section in the mathematical model of the oblique truncated cylinder on the installation plane, tanβ1 represents the inclination of the target plane where the end point of the thrust vector of each partition is located, and tanβ2 represents the inclination of the target plane where the end point of the oil pressure vector of each partition is located;

[0054] Step S3: According to the horizontal target correction torque M x , vertical target correction torque M y Get the target correction torque Then, the corresponding relationship between the direction angle of the projection of the major axis of the elliptical oblique section in the mathematical model of the oblique cylinder on the installation plane and the direction angle of the target correction torque is obtained.

[0055] Step S4: Combined with the equal relationship that the sum of the thrust torques of each partition in the ɑ direction is equal to the target correction torque, that is, Get the partition thrust constraint formula Or the partition oil pressure constraint formula

[0056] Step S5: Substitute α and tanβ1 into the partition thrust constraint formula to obtain i Substitute the partition thrust calculation formula into the central angle θ corresponding to each partition i Calculate the partition thrust of n partitions and convert the partition thrust to obtain the corresponding partition oil pressure; or substitute α and tanβ2 into the partition oil pressure constraint formula to obtain the partition oil pressure constraint formula about θ i The zone oil pressure calculation formula is substituted into the central angle θ corresponding to each zone. i Calculate the partition oil pressure of n partitions, convert the partition oil pressure to obtain the corresponding partition thrust, and finally obtain the shield machine partition thrust and oil pressure balanced distribution results.

[0057] Furthermore, in step S1, K=F max / P max , F max The oil pressure of a single group of cylinders reaches the maximum value P max The proportional coefficient K is determined according to the actual configuration of the shield machine hydraulic system.

[0058] Furthermore, in step S1, the positive direction of the z-axis in the spatial rectangular coordinate system O-xyz is perpendicular to the installation plane from the origin O to the shield machine's excavation direction, the positive direction of the y-axis is from the origin O in the installation plane to the shield machine's zenith direction, and the x-axis direction is determined according to the right-hand rule.

[0059] Specifically, in this embodiment, the center O1 of the circle containing the partition's equivalent force points is used as the origin O, and the horizontal and vertical corrective torques are used to describe the torques generated by the thrust cylinders. From the perspective of an observer facing the tunneling direction, the y-axis points vertically upward from the center O1, and the x-axis points horizontally to the right, perpendicular to the y-axis.

[0060] As shown in Figures 1 and 2, it is assumed that the radius of the circle where the equivalent force point (the root center of the cylinder group) of each partition in the shield machine is located is R; in this embodiment, each partition includes one cylinder group, that is, m=1; the partition thrust F of the i-th partition on the shield machine is i , Zone oil pressure P i The total thrust F that is expected to be achieved t relationship satisfaction The target correction torques that all cylinder groups expect to achieve in the horizontal direction (i.e., x direction) and the vertical direction (i.e., y direction) are M x 、M y .

[0061] In step S2, the mathematical model of the truncated cylinder is used to derive the geometric constraints that the generatrix length of the truncated cylinder conforms to. On this basis, it is obtained by analogy that when the thrust or oil pressure vector distribution model of each partition conforms to the geometric constraints, the thrust or oil pressure of each partition obtained will meet the balance requirement of the vector end points being coplanar.

[0062] Specifically, as shown in Figure 1(b) and Figure 4, the circle O1 (located in the installation plane) where the equivalent force points of each partition of the shield machine are located, the thrust or oil pressure vector of each partition, and the ellipse O2 (located in the target plane) formed by the vector vertex can be abstracted as a truncated cylinder. The highest point of the truncated cylinder is denoted as C. The generatrix passing through point C intersects with the circle O1 at point B. Then the plane O1O2CB is the symmetry plane of the truncated cylinder. The angle between this plane and the positive direction of the X-axis is denoted as α. Then α is the direction angle of the projection O1B of the major semi-axis O2C of the elliptical oblique section in the mathematical model of this truncated cylinder in the installation plane. Any generatrix AG intersects with the circle O1 at point A and with the elliptical surface at point G. The angle between the straight line O1A and the positive semi-axis of the X-axis is denoted as θ i The angle between the elliptical surface and the circular surface of the truncated cylinder is denoted as β.

[0063] From this, we can get the corresponding relationship between the mathematical model of the oblique truncated cylinder and the thrust or oil pressure vector distribution model of each partition: the length of the thrust or oil pressure vector of each partition is equal to the length of the busbar at the corresponding position, and the target total thrust F t The magnitude is equal to the sum of the partition thrusts corresponding to the equivalent force points of each partition. i is the central angle corresponding to the equivalent force point of the i-th partition, and tanβ is the inclination of the target plane where the end point of the thrust or oil pressure vector of each partition is located.

[0064] Taking any busbar AG as an example, we deduce the geometric constraints that the busbar length complies with when its vertices are coplanar. Figure 4 shows that |AG| = |AD| + |DG|, where |AD| = |O1O2|. This shows that if the line segment O1O2 is known, the length of line segment DG is sufficient to calculate the length of AG.

[0065] Since plane O1O2CB is perpendicular to the circular and elliptical end faces of the obliquely truncated cylinder, and planes AHFG, O1O2CB, and the plane containing circle O1 are perpendicular to each other, quadrilateral AHFG is a rectangle. Furthermore, quadrilateral DEFG is also a rectangle, so |DG| = |EF|. The length of line segment EF can be found within △EO2F using the formula EF| = |O2E|·tanβ. In rectangle O1O2EH, |O2E| = |O1H|, and the length of line segment O1H can be found within △O1HA using the formula |O1H| = |O1A|·cos(θ i -α) solution.

[0066] Therefore, it can be deduced that the geometric constraint that any generatrix length AG in the mathematical model of the oblique cylinder should satisfy is: i =|AG|=|O1O2|+R·cos(θ i -α)·tanβ.

[0067] Since the actual cylinder groups of the shield machine are arranged at equal angles along the circumference, the central angle corresponding to the center of each partition satisfies θ i =(i-1)·2π / n+ω (ω is the initial angle of the first group of cylinders, this phase does not affect the final result), which corresponds to the central angle of the corresponding position of the oblique cylinder. The sum of the lengths of each generatrix is ​​L t It can be expressed as:

[0068] Therefore, it can be deduced that in the mathematical model of the oblique truncated cylinder, the lengths of the generatrix and axis segments arranged at equal angles along the circumference satisfy:

[0069] For the case where the number of cylinders in each partition is the same as m, since the proportional coefficient K between the thrust and oil pressure of a single group of cylinders is a certain value, the thrust and oil pressure of the partition satisfy: F i =mKP i Therefore, when each thrust vector satisfies the coplanar condition of the terminal point, the corresponding oil pressure vectors of each partition also satisfy the coplanar condition of the terminal point. However, when the spatial position of the equivalent force point remains unchanged, F i After the conversion ratio mK is scaled to P i After that, the inclination of the vector endpoint plane will change, tanβ2≠tanβ1.

[0070] Furthermore, if balanced distribution is performed by first deriving and calculating the zone thrust and then determining the zone oil pressure based on the zone thrust, the length of each zone thrust vector is equal to the length of the generatrix at the corresponding position in the mathematical model of the truncated cylinder, and the inclination tanβ1 of the target plane where the end point of each zone thrust vector is located is equal to tanβ in the mathematical model of the truncated cylinder, then step S2 includes the following sub-steps:

[0071] Step S2-1, the geometric constraints that the truncated cylinder generatrix length in the truncated cylinder mathematical model should comply with are mapped to the thrust vector distribution model of each partition, and it is derived that when the end points of the thrust vectors of each partition are coplanar, the thrust F of the i-th partition is i The constraints that must be satisfied are: i =F b +R·cos(θ i -α)·tanβ1,

[0072] Where, the reference thrust F b It is a virtual vector that is consistent with the direction of the thrust vector of each partition. Its starting point is located at the origin O, and its end point is located at the target plane where the end point of the thrust vector of each partition is located.

[0073] Step S2-2: The relationship between the length of the truncated cylinder axis segment in the truncated cylinder mathematical model and the sum of the lengths of n equally spaced generatrixes is mapped to the thrust vector distribution model of each partition to obtain the reference thrust F b =F t / n.

[0074] Then, in step S3, according to the known horizontal target correction torque M x , vertical target correction torque M y The target correction torque can be determined Since the equivalent force points of each partition are equally spaced along the circumferential direction in the installation plane and the number of cylinder groups in each partition is the same, the direction angle of the projection O1B of the major axis O2C of the elliptical oblique section in the mathematical model of the oblique cylinder in the installation plane is equal to the direction angle of the target correction torque, that is, there is

[0075] Then, in step S4, the equation can be obtained by combining the relationship that the sum of the thrust moments of each partition in the α direction is equal to the target correction torque:

[0076] According to the above equation, we can solve the problem in step S2-1.

[0077] Finally, in step S5, the α and tanβ1 obtained in steps S3 and S4 are substituted into the partition thrust constraint formula of step S2-1 to obtain the i Partition thrust calculation formula:

[0078] Then the central angle θ corresponding to each partition i Substitute into the partition thrust calculation formula in sequence to calculate the partition thrust of n partitions; then according to The conversion relationship can be used to directly convert the partition thrust to obtain the corresponding partition oil pressure without the need to calculate and derive from the beginning, and the shield machine partition thrust and partition oil pressure balanced distribution results can be obtained conveniently and quickly.

[0079] Furthermore, if balanced distribution is performed by first deriving and calculating the zoned oil pressure and then determining the zoned thrust based on the zoned oil pressure, the length of each zoned oil pressure vector is equal to the length of the generatrix at the corresponding position in the mathematical model of the truncated cylinder, and the inclination tanβ2 of the target plane at the end point of each zoned oil pressure vector is equal to tanβ in the mathematical model of the truncated cylinder, step S2 includes the following sub-steps:

[0080] Step S2-1', the geometric constraints that the truncated cylinder generatrix length in the truncated cylinder mathematical model should meet are mapped to the oil pressure vector distribution model of each partition, and it is deduced that when the end points of the oil pressure vectors of each partition are coplanar, the oil pressure P of the i-th partition is i The constraints that must be satisfied are: i =P b +R·cos(θ i -α)·tanβ2,

[0081] Where, the reference thrust P b It is a virtual vector that is consistent with the direction of the oil pressure vector of each partition. Its starting point is located at the origin O, and its end point is located at the target plane where the end point of the oil pressure vector of each partition is located.

[0082] Step S2-2', according to the conversion relationship Get the reference oil pressure

[0083] Then, similarly, in step S3, we get

[0084] Then, in step S4, the sum of the thrust moments of each partition in the ɑ direction is equal to the target correction moment, and the solution in step S2-1' is obtained.

[0085] Finally, in step S5, the α and tanβ2 obtained in steps S3 and S4 are substituted into the partition oil pressure constraint formula of step S2-1' to obtain the formula for θ i The zone oil pressure calculation formula, and then the central angle θ corresponding to each zone i Substitute into the zone oil pressure calculation formula in turn to calculate the zone oil pressure of n zones, and then calculate the zone oil pressure according to F i =mKP i The conversion relationship can be used to directly convert the corresponding partition thrust through the partition oil pressure without the need to calculate and derive it from the beginning, and the shield machine partition thrust and partition oil pressure balanced distribution results can be obtained conveniently and quickly.

[0086] To verify the effectiveness of balanced thrust / oil pressure distribution, a simulation experiment was conducted. Taking a 9-meter-class shield machine as an example, the shield machine propulsion system consists of 19 groups of cylinders, each group consisting of two cylinders physically connected to the top of the cylinder telescopic rods via grippers. The thrust-to-oil pressure conversion coefficient for each cylinder group is K = 2*(2000-0) / (35-0), in kN / MPa. The parameters of the 19 groups of cylinders are shown in the table:

[0087] Assume that each group of cylinders is a zone with individually adjustable oil pressure, that is, the number of zones n = 19, and the number of cylinder groups in each zone m = 1. t =22489kN, horizontal target correction moment M x =-13493.4kN·m and vertical target correction torque M y =-17991.2kN·m is used as the target value for partition thrust distribution, and the distribution results are simulated. The simulation results of thrust vector spatial distribution are shown in Figure 5. The thrust values ​​corresponding to the 19 groups of cylinders are: 1663.07728181, 1520.34276725, 1341.12037083, 1144.83162011, 952.74744698, 785.68315208, 661.74274404, 594.3570892, 590.82846886, 651 .53926379, 769.91051733, 933.11486744, 1123.4665904, 1320.33812343, 1502.39538115, 1649.90963477, 1746.89542599, 1782.84283944, 1753.8564151, unit is kN. The distribution results were verified by calculation: the sum of the thrusts in each zone is 22489.0 kN, equal to the target total thrust. By multiplying each zone's thrust by the sum of the coordinates of the equivalent force points in the corresponding direction of that zone, the corresponding horizontal and vertical corrective moments are -13493.3999999999998 kN·m and 17991.2 kN·m, respectively, meeting the target corrective moments. (Minor errors due to loss of precision during computer calculations can be ignored.) The zone force distribution direction angle is -0.64350111°, the moment direction angle is -0.64350111°, and the plane inclination angle is -1.57738718°, all in rad.

[0088] The oil pressure of each group of cylinders can be adjusted individually, and the total thrust F t = 22489kN. With a radius of 1m, the equivalent force application point of the total thrust revolves around the center of the propulsion cylinder installation plane. The corresponding corrective torque changes with the equivalent force application point, which can be calculated by the following formula:

[0089] Correction torque Where γ∈(0,2π), r=1m,

[0090] The total thrust and corrective torque corresponding to each point are used as target values ​​to perform thrust distribution in different zones, and the changes in the total thrust, corrective torque, and related quantities corresponding to the distribution results are verified. The simulation results are shown in Figure 6. It can be seen that the center of force moves along the circumference while the total thrust remains unchanged, and the distribution result meets the target total thrust F t According to the distribution results, the torque and target correction torque M are calculated. x 、M y The difference is close to zero, which can meet the thrust distribution requirements.

[0091] Similarly, assuming that each group of cylinders is a zone with individually adjustable oil pressure, that is, the number of zones n = 19, m = 1, and the total thrust F t =22489kN, horizontal target correction moment M x =-13493.4kN·m and vertical target correction torque M y=-17991.2 kN·m is used as the target value to distribute the oil pressure to different zones. The distribution result is simulated. The simulation result of the oil pressure vector spatial distribution is shown in FIG7 . The oil pressure values ​​corresponding to the 19 groups of cylinders are: 14.55192622, 13.30299921, 11.73480324, 10.01727668, 8.33654016, 6.87472758, 5.79024901, 5.20062453, 5.1697491, 5.70096856, 6.73671703, 8.16475509, 9.83033267, 11.55295858, 13.14595959, 14.4367093, 15.28533498, 15.59987485, 15.34624363, all in MPa. The distribution results were verified by calculation: the sum of the thrusts for each partition is 22489.0, which equals the target total thrust. The corresponding horizontal and vertical correcting moments are -13493.400000000001 kN·m and 17991.199999999997 kN·m, respectively, meeting the target correcting moments (minimum errors due to precision loss during computer calculations can be ignored). The oil pressure distribution direction angle is -0.64350111, the torque direction angle is -0.64350111, and the target plane inclination angle is -2.2163747, all in rad. Therefore, the simulation results also verify that, under the same distribution conditions, the inclination (tan1) of the target plane at the endpoints of all partition thrust vectors differs from the inclination (tan2) of the target plane at the endpoints of all partition oil pressure vectors. For the same partition, the ratio of the assigned partition thrust to the partition oil pressure is mK.

[0092] The oil pressure of each group of cylinders can be adjusted individually, and the total thrust F t = 22489kN. With a radius of 1m, the equivalent force application point of the total thrust revolves around the center of the propulsion cylinder installation plane. The corresponding corrective torque changes with the equivalent force application point, which can be calculated by the following formula:

[0093] Correction torque Where γ∈(0,2π), r=1m,

[0094] The total thrust and corrective torque corresponding to each point are used as target values ​​to distribute the oil pressure in different zones, and the changes in the total thrust, corrective torque, and related quantities corresponding to the distribution results are verified. The simulation results are shown in Figure 8. It can be seen that the center of force moves along the circumference while the total thrust remains unchanged, and the distribution result meets the target total thrust F t According to the distribution results, the torque and target correction torque M are calculated. x 、M y The difference is close to zero, which can meet the thrust distribution requirements.

[0095] In summary, the method for balanced distribution of thrust and oil pressure in the intelligent tunneling process of a shield machine of the present invention distributes the thrust and oil pressure of each partition under the premise of a given target total thrust and horizontal and vertical target correction torques, and uses a geometric model for deduction. Under the constraint that the end points of the thrust / oil pressure vectors of each partition are located in the same plane of three-dimensional space, a single and definite balanced distribution result is obtained, and the thrust gradient of each partition after distribution is uniform, which is beneficial to the protection of the pipe ring during tunneling construction. It has strong practicality and high promotion and application value, and can lay a technical foundation for automatic / intelligent control of the shield machine posture.

[0096] The above embodiments are preferred examples of the present invention and are not intended to limit the scope of protection of the present invention.

Claims

1. A method for balancing thrust and oil pressure during intelligent tunneling of a shield machine, wherein the propulsion system of the shield machine comprises a plurality of zones with independently adjustable oil pressure, with equivalent force points equally spaced in the circumferential direction in the installation plane, each zone consisting of the same number of oil cylinder groups, and the thrust and oil pressure vector directions of the zones are perpendicular to the installation plane, characterized in that: include: Step S1, determine the number of partitions n of the shield machine, the number of cylinder groups m in each partition, the proportional coefficient K of the thrust and oil pressure of a single group of cylinders, the radius R of the circle where the equivalent force points of each partition are located, and then establish a spatial rectangular coordinate system O-xyz with the center of the circle as the origin, and then further determine the horizontal target correction torque M of all partitions relative to the origin O x , vertical target correction torque M y And the target total thrust F t ; Step S2: Using the oblique truncated cylinder mathematical model, establish the partition thrust constraint formula under the condition that the end points of the thrust vectors of each partition are coplanar: Or, establish the partition oil pressure constraint formula under the condition that the end points of each partition oil pressure vector are coplanar: In the formula, F i is the partition thrust of the ith partition, P i is the oil pressure of the ith partition, θ i is the central angle corresponding to the center of the ith partition, α is the direction angle of the projection of the major semi-axis of the elliptical oblique section in the mathematical model of the oblique cylinder in the installation plane, tanβ1 represents the inclination of the target plane where the end point of the thrust vector of each partition is located, and tanβ2 represents the inclination of the target plane where the end point of the oil pressure vector of each partition is located; Step S3: According to the horizontal target correction torque M x , vertical target correction torque M y Get the target correction torque Then, the corresponding relationship between the projection angle of the major semi-axis of the elliptical oblique section in the mathematical model of the oblique cylinder in the installation plane and the direction angle of the target correction torque is obtained. Step S4: Combined with the equal relationship that the sum of the thrust moments of each partition in the ɑ direction is equal to the target correction moment, that is, Get the partition thrust constraint formula Or the partition oil pressure constraint formula Step S5: Substitute α and tanβ1 into the partition thrust constraint formula to obtain i Zoned thrust gauge Formula, and then substitute the central angle θ corresponding to each partition i Calculate the partition thrust of n partitions, and convert the partition thrust to obtain the corresponding partition oil pressure; or substitute α and tanβ2 into the partition oil pressure constraint formula to obtain the partition oil pressure constraint formula about θ i Substitute the corresponding central angle θ of each partition into the partition oil pressure calculation formula i Calculate the zone oil pressure of n zones, convert the zone oil pressure to get the corresponding zone thrust, and finally get the balanced distribution result of zone thrust and oil pressure of shield machine.

2. The method for balanced distribution of thrust and oil pressure during intelligent tunneling of a shield machine according to claim 1 is characterized in that: In step S1, K = F max / P max , F max The oil pressure of a single cylinder reaches the maximum value P max The maximum thrust corresponding to .

3. The method for balanced distribution of thrust and oil pressure during intelligent tunneling of a shield machine according to claim 1 is characterized in that: In step S1, the positive direction of the z-axis in the spatial rectangular coordinate system O-xyz is perpendicular to the installation plane from the origin O to the tunneling direction of the shield machine, the positive direction of the y-axis is from the origin O in the installation plane to the zenith direction of the shield machine, and the direction of the x-axis is determined according to the right-hand rule.

4. The method for balanced distribution of thrust and oil pressure during intelligent tunneling of a shield machine according to claim 1, characterized in that: Step S2 includes the following sub-steps: Step S2-1, the geometric constraints that the truncated cylinder generatrix length in the truncated cylinder mathematical model should comply with are matched to the thrust vector distribution model of each partition, and it is derived that when the end points of the thrust vectors of each partition are coplanar, the thrust F of the i-th partition is i The constraints that should be satisfied are: F i =F b +R·cos(θ i -a)·tanβ1, Where, the reference thrust F b is a virtual vector that is consistent with the thrust vector direction of each partition, with its starting point located at the origin O and its end point located at the target plane where the thrust vector end point of each partition is located; Step S2-2, correspond the relationship between the length of the truncated cylinder axis section in the truncated cylinder mathematical model and the sum of the lengths of n equally spaced generatrixes to the thrust vector distribution model of each partition, and obtain the reference thrust F b =F t / n.

5. The method for balanced distribution of thrust and oil pressure during intelligent tunneling of a shield machine according to claim 1, characterized in that: Step S2 includes the following sub-steps: Step S2-1', the geometric constraints that the generatrix length of the oblique cylinder in the oblique cylinder mathematical model should comply with Corresponding to the oil pressure vector distribution model of each partition, it is deduced that when the end points of the oil pressure vectors of each partition are coplanar, the oil pressure P of the i-th partition is i The constraints that should be satisfied are: P i =P b +R·cos(θ i -a)·tanβ2, Where, the reference thrust P b is a virtual vector that is consistent with the direction of the oil pressure vector of each partition, with its starting point located at the origin O and its end point located at the target plane where the end point of the oil pressure vector of each partition is located; Step S2-2', according to The conversion relationship of

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