Optimization Method for TBM Operating Parameters Based on Specific Energy-Penetration Response Relationship

Abstract

The present invention discloses an optimization method for TBM operation parameters based on the specific energy - penetration response relationship, which includes establishing a comprehensive database according to the rock mass properties and TBM real - time monitoring parameters of several specific projects, introducing the field penetration index FPI, constructing the response relationship between the specific energy of rock breaking and the cutter penetration, normalizing the normal thrust of the TBM equipment, establishing the SFPI evaluation best - fitting model based on different stepwise regression analyses, drawing the interaction diagram of cutter penetration and specific energy of rock breaking based on the operation limitations of cutter bearing capacity, maximum torque and the geometric constraints of assembled cutters, adding the theoretical action line of the specific energy of rock breaking in this diagram, determining the optimal cutter penetration and the optimal specific energy of rock breaking according to the boundary intersection points between the action line of the specific energy of rock breaking and the interaction diagram, and then calculating the optimal operation parameters of the TBM. The present invention solves the problem that the existing TBM construction only depends on the subjective judgment of operators, resulting in low construction efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of tunnel construction, and relates to an optimization method for TBM operation parameters based on the specific energy-penetration response relationship. Background Technique

[0002] The full-face hard rock tunnel boring machine (TBM) is the most common tunnel construction machinery and equipment at present. Due to its advantages such as construction safety, high efficiency, and environmental protection, it has become the preferred method for the excavation of deep-buried long hard rock tunnels. However, due to the complex underground geological conditions of TBM tunneling operations, its strategy generally depends on the subjective judgment of operators and lacks scientific guidance. This often leads to low tunneling efficiency, unreasonable tool wear, and even machine blockage or functional failure, resulting in construction progress delays and additional costs.

[0003] The specific energy of tunnel rock breaking (SE), abbreviated as specific energy, is a comprehensive index for quantitatively describing the tunnel excavation speed and tool wear. For a certain constant excavation section in a specific TBM project, the penetration directly determines the amount of energy required to break the rock during tunneling. Therefore, based on the response relationship between specific energy and penetration, developing a quantitative optimization method for equipment operation parameters plays an important role in formulating a scientific and reasonable tunneling operation strategy, improving rock breaking efficiency, and extending tool life. Summary of the Invention

[0004] The purpose of the present invention is to provide an optimization method for TBM operation parameters based on the specific energy-penetration response relationship, which solves the problem that the existing TBM construction only depends on the subjective judgment of operators, resulting in low construction efficiency.

[0005] The technical solution adopted by the present invention is an optimization method for TBM operation parameters based on the specific energy-penetration response relationship, including the following steps:

[0006] Step 1, according to a number of TBM hard rock construction tunnels investigated, establish a comprehensive database based on rock mass properties and real-time monitoring parameters of the TBM during construction;

[0007] Step 2, based on the comprehensive database, introduce the field penetration index FPI to construct the response relationship between the specific energy of rock breaking and the tool penetration;

[0008] Step 3, normalize the normal thrust of the TBM equipment, and the obtained standardized field penetration index SFPI is directly determined by the rock mass properties. Based on different stepwise regression analyses, establish the best fitting model for SFPI evaluation;

[0009] Step 4, based on the maximum torque level of the cutterhead, solve the action relationship between the specific energy of rock breaking and the tool penetration, and combine the operation limitations of the maximum load of the TBM and the geometric constraints of the assembled tools to draw the interaction diagram P of the tool penetration and the specific energy of rock breaking rev -SETBM ;

[0010] Step 5: According to different rock mass conditions, add the theoretical action line of TBM rock-breaking specific energy to the interaction diagram, and determine the optimal cutter penetration and the optimal rock-breaking specific energy based on the intersection points of the theoretical action line of rock-breaking specific energy and the boundaries in the interaction diagram.

[0011] Step 6: Based on the optimal cutter penetration and the optimal rock-breaking specific energy, obtain the best operating parameters of the TBM.

[0012] In Step 1, establish a comprehensive database based on the rock mass properties and the real-time monitoring parameters of the TBM during construction. The rock mass properties include the uniaxial compressive strength σ of the rock mass c , the rock abrasiveness index CAI, the rock mass integrity K v and the rock mass rating RMR. The real-time monitoring parameters of the TBM during construction include the cutterhead torque, the total thrust force, the cutterhead rotation speed, and the cutterhead penetration.

[0013] In Step 2, based on the TBM tunneling specific energy calculation formula (1), introduce the field penetration index FPI, and construct the response relationship (2) between the rock-breaking specific energy and the cutter penetration, which is specifically as follows:

[0014]

[0015]

[0016] In the formula, SE TBM is the rock-breaking specific energy, F n is the normal force of a single cutter, k is the correction coefficient to eliminate the influence caused by the difference in cutterhead and hob arrangement, P rev is the cutterhead penetration, d * is the weighted value of the diameters of all disc cutters, and S is the spacing between adjacent cutters.

[0017] The specific process of Step 3 is as follows:

[0018] Step 3.1: Assume that the load borne by a single hob acts uniformly on the entire cutterhead panel. Then, adjust the single cutter thrust according to the TBM diameter d. Assume that the effective action area of the normal force of the hob transmitted to the cutterhead during the rock-breaking process is the product of the cutter edge width and the cutting distance. Then, obtain the "normalized" normal force of a single cutter:

[0019]

[0020] In the formula, is the normalized normal force of a single cutter, T is the cutter edge width, D is the cutterhead diameter, and N is the number of disc cutters;

[0021] Step 3.2, normalize the normal thrust of the TBM equipment. The obtained standardized field penetration index SFPI is directly determined by the rock mass properties, that is

[0022]

[0023] Step 3.3, based on the comprehensive database, establish the best-fit model for SFPI evaluation using different stepwise regression analyses:

[0024] SFPI = a·(o c ) b ·(CAI) c ·(K v ) d ·(RMR) e (5)

[0025] In the formula, a, b, c, d, and e are all fitting coefficients.

[0026] The specific process of Step 4 is as follows:

[0027] Step 4.1, considering the influence of different rotational speed conditions, solve the relationship between the rock-breaking specific energy and the cutter penetration based on the maximum torque level of the cutterhead:

[0028]

[0029] P m = Tor·RPM / 9.55 (7)

[0030] In the formula, η is the mechanical conversion factor, P m is the rated power of the shield machine, Tor is the cutterhead torque, and RPM is the cutterhead rotational speed;

[0031] Step 4.2, based on Formula (1) and Formula (5), convert Formula (4) into the rock-breaking specific energy SE TBM Formula:

[0032]

[0033] Step 4.3, determine the maximum load F max of the TBM, use Formula (9) to obtain the theoretical cutterhead penetration P rev-th , substitute the theoretical cutterhead penetration P rev-th into Formula (8), that is, let P rev = P rev-th in Formula (8), and obtain the maximum limit value of the rock-breaking specific energy, denoted by SE TBM-th , SE TBM-th is the theoretical upper boundary of the interaction diagram. Then, when P rev ≤ P rev-th , SE TBM = SETBM-th , where:

[0034]

[0035] Step 4.4. Determine the theoretical upper right boundary of the interaction diagram according to formula (6), that is, when P rev > P rev-th , determine the rock-breaking specific energy corresponding to the cutterhead penetration according to formula (6).

[0036] Step 4.5. Determine the maximum limit value of the cutter penetration according to the assembly position and geometric shape of the gauge cutter, that is, the theoretical right boundary of the interaction diagram;

[0037] Step 4.6. Use P rev as the horizontal coordinate axis and SE TBM as the vertical coordinate axis to draw the interaction diagram.

[0038] In Step 5, add the theoretical action line of the rock-breaking specific energy to the interaction diagram, and the theoretical action line of the rock-breaking specific energy is determined by formula (8).

[0039] In Step 6, based on the optimal cutter penetration and the optimal rock-breaking specific energy, calculate the best operating parameters of the TBM, including the best total thrust, cutterhead torque, and drilling speed:

[0040]

[0041] Tor opt = R 2 ·P rev-opt ·SE TBM-opt / 2η (11)

[0042] PR opt = P rev-opt ·RPM·60 / 1000 (12)

[0043] In the formula, TF opt is the best total thrust of the TBM, Tor opt is the best cutterhead torque, PR opt is the best drilling speed, P rev-opt is the optimal cutter penetration, SE TBM-opt is the optimal rock-breaking specific energy, R is the cutterhead excavation radius, and f m is the shield friction force.

[0044] The beneficial effects of the present invention are as follows:

[0045] (1) Establish a comprehensive database based on rock mass properties and real-time monitoring parameters of the TBM during construction. Starting from the commonalities and characteristics of various types of rock masses, after introducing the in-situ penetration index FPI, construct the response relationship between the specific energy of rock breaking and the cutter penetration, which is more scientific and comprehensive;

[0046] (2) Propose a standardized in-situ penetration index SFPI that only characterizes the characteristics of rock masses, eliminating more TBM design parameters such as the equivalent thrust per cutter and the penetration per revolution, making the relationship between the specific energy and the penetration obtained by this method more concise and clear;

[0047] (3) Use the SFPI concept to effectively establish the quantitative relationship between rock mass conditions, TBM operating parameters, and technical specifications, and develop a prediction model for the normalized normal thrust of TBM equipment, that is, the SFPI evaluation best-fit model, improving the applicability of the model;

[0048] (4) Comprehensively consider the operation limitations of the maximum load of the TBM, the maximum torque level of the cutterhead, and the geometric constraints of the assembled cutters, and based on the constructed SFPI evaluation best-fit model, draw the specific energy-penetration interaction diagram and the theoretical action line of the specific energy of rock breaking under the influence of different cutterhead rotation speeds of the TBM, which can more scientifically and intuitively select the best operating parameters of the TBM equipment, and solve the problem that the existing TBM construction depends on the subjective experience judgment of operators, resulting in low construction efficiency. Description of the Drawings

[0049] Figure 1 is the flow schematic diagram of the TBM operation parameter optimization method based on the specific energy-penetration response relationship of the present invention;

[0050] Figure 2 is the best relationship diagram of SFPI and σ c obtained by binary regression analysis in Example 3;

[0051] Figure 3 is the best relationship diagram of SFPI and CAI obtained by binary regression analysis in Example 3;

[0052] Figure 4 is the best relationship diagram of SFPI and K v obtained by binary regression analysis in Example 3;

[0053] Figure 5 is the best relationship diagram of SFPI and RMR obtained by binary regression analysis in Example 3;

[0054] Figure 6 is the result schematic diagram of the 1:1 comparison between the measured SFPI and the predicted SFPI in Example 3;

[0055] Figure 7It is the interaction diagram of the tool penetration and the specific energy of rock breaking drawn in Embodiment 3. Detailed implementation manners

[0056] The present invention will be described in detail below with reference to the accompanying drawings and specific implementation manners.

[0057] Embodiment 1

[0058] A method for optimizing TBM operation parameters based on the specific energy-penetration response relationship, see Figure 1 , including the following steps:

[0059] Step 1: According to several TBM hard rock construction tunnels investigated, a comprehensive database is established based on the rock mass properties and the real-time monitoring parameters of the TBM during construction. The rock mass properties include the uniaxial compressive strength σ of the rock mass c , the abrasiveness index CAI of the rock mass, the integrity K of the rock mass v and the rock mass rating RMR. The real-time monitoring parameters of the TBM during construction include the cutterhead torque, the total thrust force, the cutterhead rotation speed, and the cutterhead penetration;

[0060] Step 2: Based on the comprehensive database, the field penetration index FPI is introduced to construct the response relationship between the specific energy of rock breaking and the tool penetration;

[0061] Step 3: The standardized field penetration index SFPI obtained by normalizing the normal thrust force of the TBM equipment is directly determined by the rock mass properties, and the SFPI evaluation best-fit model is established based on different stepwise regression analyses;

[0062] Step 4: Based on the maximum torque level of the cutterhead, the action relationship between the specific energy of rock breaking and the tool penetration is solved, and combined with the operation limits of the maximum load of the TBM and the geometric constraints of the assembled tools, the interaction diagram P of the tool penetration and the specific energy of rock breaking is drawn rev -SE TBM ;

[0063] Step 5: According to different rock mass conditions, the operable specific energy line, that is, the theoretical action line of the specific energy of rock breaking, is added to the interaction diagram, and the optimal tool penetration and the optimal specific energy of rock breaking are determined according to the intersection points of the theoretical action line of the specific energy of rock breaking and the boundaries in the interaction diagram;

[0064] Step 6: Based on the optimal tool penetration and the optimal specific energy of rock breaking, the best operating parameters of the TBM are obtained, including the best total thrust force, cutterhead torque, and drilling speed.

[0065] Embodiment 2

[0066] A method for optimizing TBM operation parameters based on the specific energy-penetration response relationship, including the following steps:

[0067] Step 1: Based on several TBM hard rock construction tunnels investigated, establish a comprehensive database according to the rock mass properties and the real-time monitoring parameters of the TBM during construction. The rock mass properties include the uniaxial compressive strength σ of the rock mass c , the abrasivity index CAI of the rock mass, the integrity K of the rock mass v and the rock mass rating RMR. The real-time monitoring parameters of the TBM during construction include cutterhead torque, total thrust, cutterhead rotation speed, and cutterhead penetration;

[0068] Step 2: Based on the comprehensive database and the TBM tunneling specific energy calculation formula (1), introduce the field penetration index FPI and construct the response relationship formula (2) between the rock-breaking specific energy and the cutter penetration, as follows:

[0069]

[0070]

[0071] In the formula, SE TBM is the rock-breaking specific energy, F n is the normal force of a single cutter, k is the correction coefficient to eliminate the influence caused by the difference in cutterhead and hob arrangement, P rev is the cutterhead penetration, d * is the weighted value of the diameters of all disc cutters, and S is the spacing between adjacent cutters.

[0072] Step 3: The standardized field penetration index SFPI obtained after normalizing the normal thrust of the TBM equipment is directly determined by the rock mass properties, and establish the best fitting model for SFPI evaluation based on different stepwise regression analyses;

[0073] The specific process of Step 3 is as follows:

[0074] Step 3.1: Assume that the load borne by a single cutter acts uniformly on the entire cutterhead panel, then the single cutter thrust is adjusted according to the TBM diameter d. Assume that the effective action area of the normal force of the cutter transmitted on the cutterhead during the rock-breaking process is the product of the cutter edge width and the cutting distance, then the "normalized" normal force of a single cutter is obtained:

[0075]

[0076] In the formula, is the normalized normal force of a single cutter, T is the cutter edge width, D is the cutterhead diameter, and N is the number of disc cutters;

[0077] Step 3.2: Normalize the normal thrust of the TBM equipment, and the obtained standardized field penetration index SFPI is directly determined by the rock mass properties, that is

[0078]

[0079] Step 3.3, based on the comprehensive database, establish the best-fit model for SFPI evaluation using different stepwise regression analyses:

[0080] SFPI = a·(σ c ) b ·(CAI) c ·(K v ) d ·(RMR) e (5)

[0081] where a, b, c, d, and e are all fitting coefficients.

[0082] Step 4, solve the relationship between the specific energy of rock breaking and the penetration of the cutter based on the maximum torque level of the cutter head, and combine the operation limits of the maximum load of the TBM and the geometric constraints of the assembled cutters to draw the interaction diagram P rev -SE TBM ;

[0083] The specific process of Step 4 is as follows:

[0084] Step 4.1, considering the influence of different rotational speed conditions, solve the relationship between the specific energy of rock breaking and the penetration of the cutter based on the maximum torque level of the cutter head:

[0085]

[0086] P m = Tor·RPM / 9.55 (7)

[0087] where η is the mechanical conversion factor, P m is the rated power of the shield machine, Tor is the cutter head torque, and RPM is the cutter head rotational speed;

[0088] Step 4.2, based on Formula (1) and Formula (5), transform Formula (4) into the specific energy of rock breaking SE TBM formula:

[0089]

[0090] Step 4.3, determine the maximum load F max of the TBM, use Formula (9) to obtain the theoretical cutter head penetration P rev-th , substitute the theoretical cutter head penetration P rev-th into Formula (8), that is, let P rev = P rev-th in Formula (8), obtain the maximum limit value of the specific energy of rock breaking, denoted by SE TBM-th , SE TBM-th is the theoretical upper boundary of the interaction diagram. Then when P rev ≤ P rev-th SETBM = SE TBM-th , where:

[0091]

[0092] Step 4.4, determine the theoretical upper right boundary of the interaction diagram according to formula (6), that is, when P rev > P rev-th , determine the specific energy of rock breaking corresponding to the cutter head penetration according to formula (6).

[0093] Step 4.5, determine the maximum limit value of the cutter penetration according to the assembly position and geometric shape of the gauge cutter, that is, the theoretical right boundary of the interaction diagram;

[0094] Step 4.6, taking P rev as the horizontal coordinate axis and SE TBM as the vertical coordinate axis, draw the interaction diagram.

[0095] Step 5, according to different rock mass conditions, add the theoretical action line of the specific energy of rock breaking in the interaction diagram. The theoretical action line of the specific energy of rock breaking is determined by formula (8). Determine the optimal cutter penetration and the optimal specific energy of rock breaking according to the intersection points of the theoretical action line of the specific energy of rock breaking and the boundaries in the interaction diagram;

[0096] Step 6, based on the optimal cutter penetration and the optimal specific energy of rock breaking, calculate the best operating parameters of the TBM, including the best total thrust, cutter head torque and drilling speed:

[0097]

[0098] Tor opt = R 2 ·P rev-opt ·SE TBM-opt / 2η (11)

[0099] PR opt = P rev-opt ·RPM·60 / 1000 (12)

[0100] In the formula, TF opt is the best total thrust of the TBM, Tor opt is the best cutter head torque, PR opt is the best drilling speed, P rev-opt is the optimal cutter penetration, SE TBM-opt is the optimal specific energy of rock breaking, R is the excavation radius of the cutter head, f m is the shield friction force.

[0101] Example 3

[0102] An optimization method for TBM operation parameters based on the specific energy-penetration response relationship, comprising the following steps:

[0103] Step 1, in this embodiment, according to 219 TBM hard rock construction tunnels investigated, a comprehensive database is established based on rock mass properties and real-time TBM monitoring parameters during construction. The rock mass properties include uniaxial compressive strength σ of the rock mass c , abrasivity index CAI of the rock mass, integrity K of the rock mass v and rock mass rating RMR. The real-time TBM monitoring parameters during construction include cutterhead torque, total thrust force, cutterhead rotation speed, and cutterhead penetration;

[0104] Step 2, based on the comprehensive database, the relationships among rock mass properties, rock-breaking specific energy, and cutter penetration are analyzed in detail. In order to eliminate the influence of redundant parameters as much as possible, the field penetration index FPI is introduced to transform the TBM tunneling specific energy calculation formula (1) into formula (2):

[0105]

[0106]

[0107] In the formula, SE TBM is the rock-breaking specific energy, F n is the normal force of a single cutter, k is a correction coefficient to eliminate the influence caused by the difference in cutterhead and hob arrangement, P rev is the cutterhead penetration, d * is the weighted value of the diameters of all disc cutters, and S is the spacing between adjacent cutters.

[0108] It can be seen from formula (2) that for a specific tunnel project, the geological unit and TBM technical specifications are specific, and the change trend of SE TBM -P rev is determined by the field penetration index combined with thrust and penetration.

[0109] Step 3, in order to eliminate the influence of TBM equipment and operation parameters, the standardized field penetration index SFPI obtained after normalizing the normal thrust force of the TBM equipment is directly determined by the rock mass properties, and the SFPI evaluation best-fit model is established based on different stepwise regression analyses;

[0110] The specific process of step 3 is as follows:

[0111] Step 3.1, reasonably assume that the load borne by a single hob acts uniformly on the entire cutterhead panel, then the single-cutter thrust is adjusted according to the TBM diameter d. Reasonably assume that the effective action area of the normal force of the hob transmitted to the cutterhead during the rock-breaking process is the product of the cutter edge width and the cutting distance, then the "normalized" single-cutter normal force is obtained:

[0112]

[0113] In the formula, is the normalized single - cutting normal force, T is the cutting edge width of the tool, D is the cutterhead diameter, and N is the number of disk cutters;

[0114] Step 3.2, As can be seen from Equation (3), once the thrust is normalized, the obtained standardized field penetration index SFPI is directly determined by the rock mass properties. Then, the standardized field penetration index SFPI obtained after normalizing the normal thrust of the TBM equipment is directly determined by the rock mass properties, that is

[0115]

[0116] Step 3.3, Use simple binary regression analysis to obtain the best relationship between SFPI and UCS, CAI, K V and RMR, as Figures 2 to 5 shown. In the figure, R 2 is the correlation coefficient between the independent variable and the dependent variable. The larger R 2 is, the more obvious the linear relationship between the independent variable and the dependent variable is. The results prove that the normalization used in this method is reasonable.

[0117] Step 3.4, Based on the comprehensive database, use different stepwise regression analyses to establish the best - fitting model for SFPI evaluation:

[0118]

[0119] Step 3.5, Use Equation (5) to compare the measured SFPI with the predicted SFPI on a 1:1 basis. The results are as Figure 6 shown. There is a good consistency between the actual value and the estimated value. At the same time, R 2 = 0.73 indicates a strong correlation.

[0120] Step 4, Based on the actual engineering data of the typical granite porphyry tunneling sections of four different geological units of a certain water conveyance tunnel, as shown in Appendix 1, draw the interaction diagram P rev -SE TBM ;

[0121] The specific process of Step 4 is as follows:

[0122] Step 4.1, Since the TBM adjusts its rotational speed during normal tunneling to match the torque level suitable for different strata conditions, considering the influence of different rotational speed conditions, solve the relationship between the rock - breaking specific energy and the cutter penetration based on the maximum torque level of the cutterhead:

[0123]

[0124] Pm = Tor·RPM / 9.55 (7)

[0125] Where η is the mechanical conversion factor, P m is the rated power of the shield machine, Tor is the cutter head torque, and RPM is the cutter head rotation speed;

[0126] Step 4.2, based on Formula (1) and Formula (5), transform Formula (4) into the specific energy of rock breaking SE TBM Formula:

[0127]

[0128] Step 4.3, determine the maximum load F of the TBM max , and use Formula (9) to obtain the theoretical cutter head penetration P rev-th , and substitute the theoretical cutter head penetration P rev-th into Formula (8), that is, let P in Formula (8) rev = P rev-th , to obtain the maximum limit value of the specific energy of rock breaking, denoted by SE TBM-th , SE TBM-th is the theoretical upper boundary of the interaction diagram. Then when P rev ≤ P rev-th , SE TBM = SE TBM-th , where:

[0129]

[0130] Step 4.4, determine the theoretical upper right boundary of the interaction diagram according to Formula (6), that is, when P rev > P rev-th , determine the specific energy of rock breaking corresponding to the cutter head penetration according to Formula (6);

[0131] Step 4.5, determine the maximum limit value of the cutter penetration according to the assembly position and geometric shape of the gauge cutter, that is, the theoretical right boundary of the interaction diagram;

[0132] Step 4.6, with P rev as the horizontal axis and SE TBM as the vertical axis, draw the interaction diagram, as shown in Figure 7 , Figure 7 The theoretical boundary line in is the interaction diagram.

[0133] Step 5, according to different rock mass conditions, add the theoretical action line of the specific energy of rock breaking in the interaction diagram. The theoretical action line of the specific energy of rock breaking is determined by Formula (8), that is Figure 7 The specific energy action line in. Determine the optimal cutter penetration P according to the intersection point of the theoretical action line of the specific energy of rock breaking and the boundary in the interaction diagram rev-optand the optimal specific energy of rock breaking SE TBM-opt , as specifically shown in Table 1;

[0134] Step 6, based on the optimal cutter penetration and the optimal specific energy of rock breaking, calculate the best operating parameters of the TBM, including the best total thrust, cutterhead torque, and drilling speed:

[0135]

[0136] Tor opt =R 2 ·P rev-opr ·SE TBM-opt / 2η (11)

[0137] PR opt =P rev-opt ·RPM·60 / 1000 (12)

[0138] In the formula, TF opt is the best total thrust of the TBM, Tor opt is the best cutterhead torque, PR opt is the best drilling speed, P rev-opt is the optimal cutter penetration, SE TBM-opt is the optimal specific energy of rock breaking, R is the excavation radius of the cutterhead, f m is the shield friction force, f m =0.2G, where G is the self-weight of the TBM.

[0139] The best operating parameters of the TBM calculated under the four working conditions are shown in Table 1. Compare the obtained best operating parameters of the TBM with the actual construction machinery parameters. See Figure 7 . The actual construction machinery parameters are determined by the existing method, that is, mainly by the subjective judgment of the operators, Figure 7 and the working point of the original project in

[0140] is the working point determined by the existing method. Through comparison, it is found that under the conditions of Working Condition 1, the optimal cutter penetration determined by the method of the present invention is nearly 25% higher (about 11.5 mm / rev) than the actual operation (about 9.2 mm / rev); while maintaining the maximum drilling speed, the optimal specific energy of rock breaking in the tunneling section of Working Condition 4 is only about 22.1 MJ / m 3 , which is nearly 30% lower in energy consumption than the actual operation (about 31 MJ / m 3 ), indicating that the TBM operation parameters optimized by the method of the present invention can not only improve the construction efficiency but also greatly reduce the energy consumption.

[0141] Table 1 Actual project data and corresponding best operating parameters of the TBM

[0142] Operating condition 1 2 3 4 Geological unit number HJ-3-97 HJ-3-104 HJ-3-115 HJ-3-118 Rock mass Granite porphyry Granite porphyry Granite porphyry Granite porphyry Interval length (m) 153 325 78 230 Geology Weakly weathered Slightly weathered Weakly weathered Fresh <![CDATA[σ c (MPa)]]> 67 102 138 183 CAI 3.52 5.65 6.26 5.14 <![CDATA[K v > 0.39 0.52 0.68 0.71 RMR 65 78 86 92 RPM (rev / min) 4.2 5.2 5.9 7.3 <![CDATA[P rev-opt (mm / rev)]]> 11.5 7.5 5.6 4.5 <![CDATA[SE TBM-opt (MJ / m 3 )]]> 14.7 18.2 21.5 22.1 <![CDATA[TF opt (MN)]]> 9.7 8.5 7.8 7.3 <![CDATA[Tor opt (MN·m)]]> 1.9 1.5 1.4 1.1 <![CDATA[PR opt (mm / min)]]> 2.9 2.3 2.0 2.0

Claims

1. A TBM operating parameter optimization method based on the specific energy-penetration response relationship, characterized in that: The following steps are involved: Step 1: Based on the investigated TBM hard rock tunnels, a comprehensive database is established according to the rock mass properties and the TBM real-time monitoring parameters during construction; In step 1, a comprehensive database is established based on rock mass properties and TBM real-time monitoring parameters during construction. The rock mass properties include the uniaxial compressive strength σ c , rock abrasiveness index CAI, rock integrity K v and rock mass rating RMR. Real-time monitoring parameters of TBM during construction include cutterhead torque, total thrust, cutterhead speed and cutterhead penetration; Step 2: Based on the comprehensive database, the field penetration index (FPI) is introduced to construct the response relationship between rock breaking specific energy and tool penetration; In step 2, based on the TBM excavation specific energy calculation formula (1), the field penetration index FPI is introduced to construct the response relationship between rock breaking specific energy and tool penetration (2), which is as follows: In the formula, SE TBM is the rock breaking specific energy, F n is the normal force of a single cutter, k is the correction coefficient to eliminate the influence of the arrangement difference between the cutter head and the hob, P rev is the penetration of the cutter head, d * is the weighted value of all disc-shaped hob diameters, S is the distance between adjacent hobs; Step 3: Normalize the normal thrust of the TBM equipment. The obtained standardized field penetration index (SFPI) is directly determined by the rock mass properties. The best fitting model for SFPI evaluation is established based on the regression analysis of different step progress. The specific process of step 3 is as follows: Step 3.1, assuming that the load borne by a single disc cutter acts evenly on the entire cutterhead panel, the single cutter thrust is adjusted according to the TBM diameter d. Assuming that the effective action area of ​​the disc cutter normal force transmitted on the cutterhead during rock breaking is the product of the blade width and the cutting distance, the "normalized" single cutter normal force is obtained: In the formula, is the normalized single-tool normal force, T is the tool edge width, D is the cutter head diameter, and N is the number of disc-shaped hobs; Step 3.2, normalize the normal thrust of the TBM equipment, and the obtained standardized field penetration index SFPI is directly determined by the rock mass properties, that is, Step 3.3, based on the comprehensive database, the best-fitting model for SFPI assessment was established using stepwise regression analysis: SFPI=a·(σ c ) b ·(CAI) c ·(K v ) d ·(RMR) e (5) In the formula, a, b, c, d and e are fitting coefficients; Step 4: Based on the maximum torque level of the cutterhead, the relationship between rock breaking energy and tool penetration is obtained. Combined with the operational constraints of the maximum load of the TBM and the geometric constraints of the assembled cutter, the interaction diagram between tool penetration and rock breaking energy is drawn. rev -SE TBM ; Step 5: According to different rock mass conditions, the theoretical action line of rock breaking energy is added to the interaction diagram, and the optimal tool penetration and the optimal rock breaking energy are determined according to the boundary intersection point between the theoretical action line of rock breaking energy and the interaction diagram; Step 6: Based on the optimal tool penetration and the optimal rock breaking specific energy, the optimal operating parameters of the TBM are obtained.

2. The TBM operation parameter optimization method based on specific energy-penetration response relationship according to claim 1 is characterized in that: The specific process of step 4 is as follows: Step 4.1, considering the influence of different speed conditions, the relationship between rock breaking specific energy and tool penetration is solved based on the maximum torque level of the cutterhead: P m =Tor·RPM / 9.55 (7) Where η is the mechanical conversion factor, P m is the rated power of the shield machine, Tor is the cutterhead torque, and RPM is the cutterhead speed; Step 4.2: Based on formula (1) and formula (5), convert formula (4) into rock breaking specific energy SE TBM formula: Step 4.3, determine the maximum load F of the TBM max , using formula (9) to obtain the theoretical cutter penetration P rev-th , the theoretical cutter penetration P rev-th Substitute into formula (8), that is, let P in formula (8) rev =P rev-th , obtain the maximum limit of rock breaking specific energy, and use SE TBM-th Indicates that SE TBM-th That is, the theoretical boundary of the interaction diagram, then when P rev ≤P rev-th When TBM =SE TBM-th ,in: Step 4.4, determine the theoretical upper right boundary of the interaction diagram according to formula (6), that is, when P rev >P rev-th When , the rock breaking specific energy corresponding to the cutter head penetration is determined by formula (6); Step 4.5, determining the maximum limit of tool penetration according to the assembly position and geometric shape of the gauge disc tool, that is, the theoretical right boundary of the interaction diagram; Step 4.6, with P rev is the horizontal coordinate axis, SE TBM With as the vertical axis, draw the interaction diagram.

3. The TBM operation parameter optimization method based on specific energy-penetration response relationship according to claim 2 is characterized in that: In the step 5, the theoretical action line of rock-breaking specific energy is added to the interaction diagram, and the theoretical action line of rock-breaking specific energy is determined by formula (8).

4. The TBM operation parameter optimization method based on specific energy-penetration response relationship according to claim 3 is characterized in that: In step 6, based on the optimal tool penetration and the optimal rock breaking specific energy, the optimal operating parameters of the TBM are calculated, including the optimal total thrust, cutter head torque and drilling speed: Tor opt =R 2 ·P rev-opt ·SE TBM-opt / 2η (11) PR opt =P rev-opt ·RPM·60 / 1000 (12) Where TF opt For the best total thrust of the TBM, Tor opt For the best cutter torque, PR opt is the optimal drilling speed, P rev-opt is the optimal tool penetration, SE TBM-opt is the optimal rock breaking specific energy, R is the cutter head excavation radius, f m is the shield friction.

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