Cutter optimization arrangement method and system for slurry shield cutterhead

Abstract

The invention discloses a cutter optimal arrangement method and system for a slurry shield cutter head, relates to the technical field of shield cutter heads, and provides an optimal arrangement method and system for front cutters of the slurry shield cutter head. The method comprises the following steps: obtaining front cutter structure parameters and working conditions to determine cutter arrangement parameters; based on the cutting process of the cutter and the cutter arrangement parameters, a ground breaking amount model is established; according to the Rankine passive earth pressure theory, a cutting force model is established in combination with a tillage tool cutting resistance model and the synergistic effect and cutting mechanism of a tool; then, based on the ground breaking amount model and the cutting force model, establishing a cutting efficiency model; and finally, evaluating the cutting efficiency under different cutter combination arrangement parameters through the cutting efficiency model, and selecting the cutter arrangement parameter with the highest cutting efficiency as an optimal arrangement scheme. The accuracy of the cutter arrangement parameters of the slurry shield cutterhead can be improved, and then the tunneling efficiency of the slurry shield cutterhead is improved.

Description

Technical Field

[0001] The present application relates to the technical field of shield cutter discs, and in particular to a method and system for optimizing the arrangement of cutters of a slurry shield cutter disc. Background Art

[0002] At present, shield is an indispensable large-scale engineering equipment in modern tunnel engineering, and has the advantages of high efficiency, environmental protection and safety in tunnel excavation. Among them, "synchronous pushing and splicing" is a new route and new requirement for large-diameter slurry shield construction projects. In engineering projects, faced with complex working conditions such as long construction distances and large excavation sections, there will be problems of low excavation efficiency and frequent shutdowns in construction projects.

[0003] Therefore, in response to the above problems, higher requirements are put forward for the comprehensive performance of the large-diameter slurry shield cutterhead. The cutter is an important tool for the shield cutterhead to achieve excavation, and the existing cutterheads are equipped with multiple types of cutters for arrangement. The quality of the cutter arrangement scheme is closely related to the excavation efficiency of the shield machine. Therefore, the optimization selection of cutter arrangement parameters is an important part of the shield cutterhead design.

[0004] The shield tunneling machine relies on the rotation of the cutterhead to drive the cutter installed on the cutterhead to cut the face rock and soil, and relies on the cylinder to push the shield tunneling machine forward, thereby achieving continuous excavation. In the actual construction process, the configuration and layout of the cutter of the shield tunneling machine have an important impact on the excavation performance. In order to improve the excavation performance, reduce construction costs, and ensure construction safety, engineers continue to optimize the configuration and layout of the cutter. For different geological conditions, it is crucial to choose the right type and combination of cutters. For example, in hard rock geology, the roller cutter becomes an indispensable tool due to its powerful rolling effect; while in soft soil layers, the cutter can cut more effectively. Through a reasonable combination of cutters, the advantages of various cutters can be fully utilized, thereby improving the overall excavation efficiency. The layout of the cutters will also affect the excavation performance. The layout of the cutters should take into account the interaction between the cutters and their contact with the face rock and soil. Reasonable cutter layout can make the cutters work better together during the excavation process, reduce the wear of the cutters, and increase the excavation speed.

[0005] For large-diameter slurry shields, the advance cutter is a tool that cuts the soil first, dividing the soil into blocks to create more favorable cutting conditions for the cutting tool. In addition to creating cutting conditions for the cutting tool, the use of the advance cutter can also significantly improve the fluidity of the cuttered soil, greatly reduce the torque applied to the cutting tool, improve the cutting efficiency of the cutting tool, and reduce the wear of the cutting tool. It is very effective in loose strata, especially in sandy and gravel strata. The combined cutting of the advance cutter and the cutter is widely used in the design of the cutterhead of soft soil shields.

[0006] The height difference between the leading cutter and the cutting cutter is the main layout parameter of the cutter combination. The appropriate height difference helps to reasonably distribute the cutting force, so that the leading cutter and the cutting cutter can work together during the cutting process and improve the overall cutting efficiency. The overlap of the cutting cutter tracks will also affect the tunneling effect. Excessive overlap may cause mutual interference between the cutters, shorten the service life of the cutters, and reduce the tunneling efficiency. The appropriate overlap can evenly distribute the cutting force, reduce local wear of the cutters, and ensure the continuity of tunneling. The adjacent and sequential cutting tools in the common cutterheads in engineering are all equipped with assembly overlaps, so that the cutterhead can smoothly cut all the rock and soil on the lower face during tunneling. Therefore, the selection of appropriate height difference and overlap is crucial in the design of the shield machine cutterhead.

[0007] From the perspective of tool layout, many researchers have explored issues such as tool structure parameter optimization, formation adaptability, and tool configuration optimization through numerical simulation and experimental methods. However, most studies only focus on the layout optimization of a single type of tool, and lack consideration of the synergy and mutual influence between positive tools.

[0008] Therefore, there is an urgent need to provide a new method or system for determining the combined tool layout scheme of the slurry shield cutter head, which can improve the accuracy of determining the tool layout parameters under the complex working conditions of long construction distances and large excavation surfaces in large-diameter slurry shield projects, thereby improving the excavation efficiency of the slurry shield cutter head. Summary of the invention

[0009] The purpose of this application is to provide a method and system for optimizing the arrangement of cutters of a slurry shield cutter head, which can improve the accuracy of the cutter arrangement parameters of the slurry shield cutter head, thereby improving the excavation efficiency of the slurry shield cutter head.

[0010] To achieve the above objectives, this application provides the following solutions:

[0011] In a first aspect, the present application provides a method for optimizing the arrangement of cutters of a slurry shield cutter head, comprising:

[0012] Obtaining the structural parameters and working conditions of the front cutter; the front cutter includes: a cutting cutter and a tearing cutter; the structural parameters of the front cutter include: cutter width, cutter thickness and cutting angle; the working conditions include: geological conditions and cutter disc size;

[0013] Determine tool placement parameters according to the front tool structure parameters and the working conditions; the tool placement parameters include: tool quantity, overlap variation range and radius range of placement area;

[0014] According to the cutting process of the tool and the tool arrangement parameters, a ground breaking volume model of the tool combination is established; the ground breaking volume model is used to determine the total ground breaking volume of the tool;

[0015] According to Rankine's passive earth pressure theory, based on the tillage tool cutting resistance model, combined with the tool synergy and cutting mechanism, a cutting force model of the tool combination is established; the cutting force model is used to determine the cutting force of the tool; the cutting force includes: tangential cutting force and vertical thrust force;

[0016] A cutting efficiency model is established according to the soil breaking volume model and the cutting force model; the cutting efficiency model is used to determine the cutting efficiency according to the total soil breaking volume and the cutting force; the cutting efficiency is the energy consumed by the cutter disc in cutting a unit of soil in one rotation cycle;

[0017] According to the cutting efficiency model, the cutting efficiency under different tool combination layout parameters is determined, and the tool layout parameters with the highest cutting efficiency are taken as the optimal layout scheme.

[0018] Optionally, the number of knives of the cutting knife and the tearing knife is the same as the radius range of the arrangement area.

[0019] Optionally, according to the front tool structure parameters and the working conditions, tool arrangement parameters are determined, specifically including:

[0020] Using the formula Determine the number of tools; where N is the number of tools, ρ max is the maximum layout radius of the tool, ρ0 is the minimum layout radius of the tool, and b1 is the cutter width;

[0021] Using the formula With formula Determine the minimum and maximum overlap of the cutter; the overlap range of the cutter is a min <a<a max ; Among them, a min is the minimum overlap of the cutter, b1 is the width of the cutter, ρ max is the maximum layout radius of the tool, ρ1 is the layout radius of the first tool, n is the tool number, a max is the maximum overlap of the cutter, a is the cutting overlap of the cutter;

[0022] Using the formula ρ n =ρ1+(n-1)(b1-a) determines the layout radius of the nth tool; where ρ n is the layout radius of the nth tool, n is the tool number, and b1 is the cutter width.

[0023] Optionally, the step of establishing a soil breaking volume model of the tool combination according to the cutting process of the tool and the tool arrangement parameters specifically includes:

[0024] The soil breaking model is determined using the formula V=V1+V2; where V1 is the soil breaking amount of the cutter, N is the number of tools, n is the tool number, b1 is the width of the cutting tool, b2 is the thickness of the tearing tool, A is the cutting depth, ρ n is the layout radius of the nth tool, V2 is the amount of soil broken by the tearing tool, H is the height difference between the cutting knife and the tearing knife, and V is the total amount of soil broken.

[0025] Optionally, the cutting force model of the tool combination is established based on the Rankine passive earth pressure theory and the cutting resistance model of the tillage tool, combined with the synergy and cutting mechanism of the tool, and specifically includes:

[0026] Using formula F H =F H1 +F H2 and formula F V =F V1 +F V2 Establish cutting force model of tool combination;

[0027] Among them, F H is the tangential cutting force, F H1 F is the horizontal cutting force of the cutter, H1 =P H1 +μp u1 (b1-b2-a)l1P H1 is the tangential reaction force of the cutting soil on the cutter, μ is the friction coefficient, and p u1 is the ultimate bearing capacity of the soil when the cutter acts on the soil, b1 is the width of the cutter, b2 is the thickness of the tearing knife, a is the overlap of the cutter cutting, l1 is the arc projection width of the cutter blade, and F H2 is the horizontal cutting force of the tearing knife, F H2 =P H2 +μp u2 b2l2,P H2 is the tangential reaction force of the cutting soil on the tearing knife, μ is the friction coefficient, and p u2 is the ultimate bearing capacity of the soil when the tearing knife acts on the soil, b2 is the thickness of the tearing knife, l2 is the arc projection width of the tearing knife blade, and F V is the vertical thrust, F V1 F is the vertical thrust of the cutter, V1 =p u1 (b1-b2-a)l1-P V1 , P V1 F is the vertical reaction force of the cutting soil on the cutter, V2 is the vertical propulsion force of the tearing knife, F V2 =p u2 b2l2-P V2 , P V2 It is the vertical reaction force of the cutting soil on the tearing knife.

[0028] Optionally, establishing a cutting efficiency model according to the ground breaking volume model and the cutting force model specifically includes:

[0029] Using the formula Establish a cutting efficiency model; where E is the cutting efficiency, F V is the vertical thrust, A is the cutting depth, N is the number of tools, n is the tool number, ρ n is the layout radius of the nth tool, F H is the tangential cutting force, and V is the total amount of ground broken.

[0030] In a second aspect, the present application provides a tool optimization arrangement system for a slurry shield cutter head, comprising:

[0031] The parameter acquisition module is used to acquire the structural parameters and working conditions of the front cutter; the front cutter includes: a cutting cutter and a tearing cutter; the structural parameters of the front cutter include: cutter width, cutter thickness and cutting angle; the working conditions include: geological conditions and cutter disc size;

[0032] An arrangement parameter determination module is used to determine the arrangement parameters of the cutters according to the front cutter structure parameters and the working conditions; the arrangement parameters of the cutters include: the number of cutters, the range of overlap, and the radius range of the arrangement area;

[0033] A ground breaking volume model establishment module is used to establish a ground breaking volume model of a tool combination according to the cutting process of the tool and the tool arrangement parameters; the ground breaking volume model is used to determine the total ground breaking volume of the tool;

[0034] The cutting force model establishment module is used to establish a cutting force model of the tool combination based on the Rankine passive earth pressure theory and the tillage tool cutting resistance model, combined with the synergy and cutting mechanism of the tool; the cutting force model is used to determine the cutting force of the tool; the cutting force includes: tangential cutting force and vertical thrust force;

[0035] A cutting efficiency model establishment module is used to establish a cutting efficiency model according to the soil breaking volume model and the cutting force model; the cutting efficiency model is used to determine the cutting efficiency according to the total soil breaking volume and the cutting force; the cutting efficiency is the energy consumed by the cutter disc in cutting a unit of soil in one rotation cycle;

[0036] The arrangement scheme determination module is used to determine the cutting efficiency under different tool combination arrangement parameters according to the cutting efficiency model, and take the tool arrangement parameters with the highest cutting efficiency as the optimal arrangement scheme.

[0037] According to the specific embodiments provided in this application, this application has the following technical effects:

[0038] The present application provides a method and system for optimizing the arrangement of cutters for a slurry shield cutter head. The present application focuses on the mutual influence and action process between the front cutters, establishes a cutting force model and a ground-breaking volume model for the cutter and the tearing cutter, and establishes a cutting efficiency model in combination with the cutting force model and the ground-breaking volume model. The cutting efficiency model can effectively evaluate the cutting efficiency of the cutter heads of large-diameter slurry shield cutters, optimize the arrangement parameters of the cutter and the tearing cutter in terms of three-dimensional and planar layout, and improve the excavation efficiency of the slurry shield cutter head when faced with complex working conditions such as long construction distances and large excavation surfaces in large-diameter slurry shield cutter head projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 This is a schematic flow chart of a method for optimizing the arrangement of cutters of a slurry shield cutter head in one embodiment of the present application;

[0041] Figure 2 A schematic diagram of the process of establishing a cutting efficiency model in one embodiment of the present application;

[0042] Figure 3 This is a flow chart of tool arrangement parameter optimization in one embodiment of the present application. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] In an exemplary embodiment, Figure 1 As shown, a method for optimizing the arrangement of cutters of a slurry shield cutter head is provided, including the following S1 to S6:

[0046] S1: Obtaining structural parameters and working conditions of the front tool; the front tool includes: a cutting tool and a tearing tool.

[0047] Among them, S1 specifically includes:

[0048] S11, determining tool parameters, which include tool width, tool thickness and cutting angle.

[0049] S12, determining soil parameters, which include: internal friction angle, cohesion and density.

[0050] S13, determining working conditions, which include: geological conditions and cutterhead size.

[0051] S2: Determine tool arrangement parameters according to the front tool structure parameters and the working conditions; the tool arrangement parameters include: the number of tools, the range of overlap, and the radius range of the arrangement area.

[0052] S2 specifically includes:

[0053] S21: Determine the radius range of the layout area of ​​the cutters according to the cutter disc diameter, the center cutter position and the edge cutter position, and calculate the number of cutters.

[0054] Take a large diameter mud cutter disc of a project in the south as an example. The diameter of the cutter disc is 15.4m. Since the center cutter is arranged in a single way and its position cannot be changed, and the edge cutter does not participate in the main cutting process, the edge cutter and the center cutter are not considered in the calculation of the cutter arrangement. Only the arrangement range of the tearing cutter and the cutter is considered, that is, the calculation radius range of the cutter arrangement is R = 2430mm ~ 7600mm. Combined with the cutter width and the requirement that the cutter disc needs to be covered with the tool cutting trajectory, the number of tearing cutters and cutters can be calculated. The calculated number of cutters N is rounded up, and the calculation formula is:

[0055]

[0056] Where N is the number of tools, ρ max is the maximum radius of tool placement, ρ0 is the minimum radius of tool placement, b1 is the width of the cutter, in this case, ρ0 = 2430 mm, ρ max =7600mm.

[0057] Considering that the tool cutting trajectories must have overlapping parts, the result is rounded up to N=24, that is, 24 normal-pressure replaceable tearing knives and 24 pairs of normal-pressure replaceable cutting knives are arranged.

[0058] S22: Due to the existence of edge cutters, the cutter with the largest arrangement radius will produce different overlaps with the edge cutters. Therefore, the overlap variation range of the overall cutter tool can be established. The determination formula is as follows:

[0059] a min <a<a max .

[0060] Among them, a minis the minimum overlap of the cutter, a max is the maximum overlap of the cutter, and a is the cutting overlap of the cutter.

[0061] The formula for determining the minimum overlap of the cutter and the maximum overlap of the cutter is as follows:

[0062]

[0063] Where b1 is the cutter width, ρ max is the maximum tool layout radius, ρ1 is the layout radius of the first tool, and n is the tool number.

[0064] S23: Calculating the arrangement radius of the tearing knife and the cutting knife under different overlap parameters according to the cutting overlap of the cutting knife.

[0065] The normal pressure replaceable tearing knife is arranged in combination with the normal pressure replaceable cutting knife. According to the principle that the leading knife is arranged at the center of the cutting knife track, the arrangement radius of the normal pressure replaceable tearing knife is equal to the center radius of the normal pressure replaceable cutting knife track.

[0066] The calculation formula for the center radius of the cutting knife and tearing knife trajectory is as follows:

[0067]

[0068] ρ2=ρ1+b1-a.

[0069] …

[0070] ρ n =ρ1+(n-1)(b1-a).

[0071] Among them, ρ n is the layout radius of the nth tool, n is the tool number, and b1 is the cutter width.

[0072] With reference to several sets of mud cutter discs, the current range of tool height difference H is generally 20 to 40 mm, and the range of tool arrangement parameters (tool height difference, overlap) is obtained.

[0073] S3: establishing a ground breaking volume model of the tool combination according to the cutting process of the tool and the tool arrangement parameters; the ground breaking volume model is used to determine the total ground breaking volume of the tool.

[0074] During the excavation process, the cutterhead tool acts on the soil, the soil is broken and falls under the force, and the soil will exert a reaction force on the cutter. Therefore, from the perspective of the relationship between the cutter and the soil, the amount of soil broken and the size of the cutter cutting force are the direct reaction results of the shield cutterhead tool during the excavation process.

[0075] In an exemplary embodiment, Figure 2As shown in the figure, based on the action mode of the cutter and the analysis of the cutting process of the cutterhead rotary excavation, the synergistic effect of the cutter is considered and a model of the earth breaking volume is established.

[0076] When the ultra-large diameter shield cutter disc is excavating, the tearing knife and the cutting knife work together to complete the cutting of the soil as the cutter disc rotates. Before the cutting knife cuts the soil, the tearing knife will first contact and cut the soil into pieces. That is, when the tool contacts the soil, since the tearing knife is higher than the cutting knife by a certain height, the tearing knife will preferentially pre-destroy the soil to form a circular gully, which creates a good cutting environment for the cutter while improving the fluidity and cutting efficiency of the cutter, reducing the cutting force of the cutter and reducing the wear of the cutting tool; when the cutting depth exceeds the height difference between the tearing knife and the replaceable cutter, the cutter starts to cut the soil; the shield cutter disc continues to excavate forward, and the tearing knife and the cutting knife maintain a joint cutting action. In each subsequent rotation cycle, the soil area cut by the cutter is always the soil area after the tearing knife acts.

[0077] According to the actual project, combined with the way the cutter acts on the soil and analyzing the cutting process of the rotary excavation of the cutter disc, the soil breaking volume model of the cutter and the tearing knife is established respectively. The soil breaking volume of the normal pressure replaceable cutter and one rotation is:

[0078]

[0079] The soil breaking capacity of the replaceable tearing knife under normal pressure is:

[0080]

[0081] Among them, V1 is the amount of soil breaking of the cutting knife, V2 is the amount of soil breaking of the tearing knife, N is the number of knives, n is the number of knives, b1 is the width of the cutting knife, b2 is the thickness of the tearing knife, A is the cutting depth, ρ n is the layout radius of the nth tool, and H is the height difference between the cutting knife and the tearing knife.

[0082] The soil breaking amount of the cutting knife and the tearing knife is taken into account to obtain the total soil breaking amount. The total soil breaking amount is calculated as follows:

[0083] V=V1+V2.

[0084] Among them, V is the total groundbreaking volume.

[0085] S4: In an exemplary embodiment, Figure 2 As shown, according to Rankine's passive earth pressure theory, based on the tillage tool cutting resistance model, combined with the synergy and cutting mechanism of the tool, a cutting force model of the tool combination is established; the cutting force model is used to determine the cutting force of the tool; the cutting force includes: tangential cutting force and vertical thrust force.

[0086] S4 specifically includes:

[0087] S41: Analyze the cutting mechanism of the tool and the changes in soil morphology under different geological conditions.

[0088] Under different geological conditions, the cutting mechanism of the pilot cutter shows significant differences. As mentioned above, when the blade initially cuts into the soil, the deformation of the soil follows a specific law. In hard soil or rock, due to the high strength of the soil itself, the shear stress generated when the blade cuts in must exceed the shear strength of the soil to cause damage. In this process, cracks usually appear in the soil first, and over time, these cracks gradually expand, eventually causing the soil to peel off in blocks. It is worth noting that when the blade cuts into a certain depth, the resistance of the soil to peel off will suddenly decrease, which is a significant feature in the cutting process of plastic soil. In looser soil, the situation is significantly different. Because the structure of loose soil is looser and its internal friction is smaller, when the blade of the pilot cuts in, the soil is more likely to be crushed as a whole under the action of smaller shear stress. When digging in loose soil, the resistance of the soil is relatively low, so the cutting force is also relatively small.

[0089] The shape of the soil being cut is closely related to factors such as the shape of the tool, the cutting angle, penetration, cutting speed, and soil properties. At present, the flow patterns of soil debris are mainly summarized into four types: flow type, fracture type, shear type, and peeling type. Generally speaking, for plastic strata, the cutting of the cutter generally manifests as a continuous cutting form, without obvious cracks or overall crushing; for looser strata, it generally manifests as overall crushing; for rock mass and hard soil with a high degree of consolidation, it is divided into two stages. The first stage is that the soil is cracked by the cutter, and the second stage is that the cracks extend until they are peeled off from the parent body.

[0090] From a mechanical point of view, it can basically be divided into the axial extrusion pressure (excavation direction) generated by the cutter on the excavation surface soil and the cutting force in the direction of the cutter head rotation (tangent direction of the tool trajectory), which causes shear damage to the soil under the cutting action, and the soil is separated along the direction of the blade. Under the extrusion action, the separated soil is deformed, separated from the soil to form soil chips, and flows along the front blade surface of the cutter.

[0091] S42: Combining the synergy of the tools and the cutting mechanism, a combined cutting force model of the tools is established based on the cutting resistance model, and then the corresponding tangential cutting force and vertical thrust force of the tearing knife and the cutting knife are obtained.

[0092] Based on Rankine's passive earth pressure theory and the cutting resistance model of tillage cutters established by McKyes-Ali, the above model divides the failure zone of the soil into a central failure zone and two half-moon failure zones on the sides. However, considering that the soil breaking model is based on the range where the cutter mainly contacts the soil, only the force of the central failure zone on the cutter is considered.

[0093] The stress analysis of the failure zone in the center of the cutter is carried out, and the force balance in the horizontal and vertical directions is as follows:

[0094]

[0095] The combined solution gives the force exerted by the cutter on the central failure zone.

[0096]

[0097] Among them, P1 is the force of the cutter on the central failure area, R is the force on the side of the soil, G is the gravity of the central failure area, Q is the additional force on the soil area, c is the soil cohesion, c a is the bonding force between soil and cutter, b is the width of the central failure zone, A is the cutting depth, γ is the soil weight, q is the additional pressure on the central failure zone, δ1 is the cutting angle of the cutter, β is the failure angle of the failure surface, φ is the internal friction angle of the soil, and φ' is the friction angle between the soil and the cutter.

[0098] The calculation formula for the width of the central failure zone is:

[0099] b=b1-b2-a.

[0100] Among them, b1 is the width of the cutting knife, b2 is the thickness of the tearing knife, and a is the overlap amount.

[0101] The reaction force of the cutter on the cutting tool is decomposed into tangential reaction force and vertical reaction force.

[0102]

[0103] Among them, P H1 is the tangential reaction force of the cutting soil on the cutter, P V1 It is the vertical reaction force of the cutter on the soil.

[0104] According to the theory of ultimate bearing capacity of soil, the ultimate bearing capacity of soil is calculated when the cutter acts on the soil.

[0105]

[0106] Among them, p u1 is the ultimate bearing capacity of the soil when the cutter acts on the soil, N1 is the first ultimate bearing capacity coefficient, and N2 is the second ultimate bearing capacity coefficient.

[0107] The force analysis of the cutter in the X and Y directions is performed to obtain the vertical thrust force of the cutter and the horizontal cutting force of the cutter. The calculation formula is as follows:

[0108]

[0109] Among them, F V1is the vertical propulsion force of the cutter, l1 is the arc projection width of the cutter blade, F H1 is the horizontal cutting force of the cutter, and μ is the friction coefficient.

[0110] The above is the force analysis of the cutting knife acting on the soil. The tearing knife and the cutting knife act on the soil in a similar way, so the cutting force model of the tearing knife can be obtained by the same logic.

[0111] The calculation formula of the force of the tearing knife on the central failure area is as follows:

[0112]

[0113] Among them, P2 is the force of the tearing knife on the central failure area, φ” is the friction angle between the soil and the tearing knife, and δ2 is the cutting angle of the tearing knife.

[0114] The reaction force of the cutting soil on the tearing knife is decomposed into tangential reaction force and vertical reaction force. The calculation formula is as follows:

[0115]

[0116] Among them, P H2 is the tangential reaction force of the cutting soil on the tearing knife, P V2 It is the vertical reaction force of the cutting soil on the tearing knife.

[0117] According to the theory of ultimate bearing capacity of soil, the ultimate bearing capacity of soil is calculated when the tearing knife acts on the soil.

[0118]

[0119] Among them, p u2 It is the ultimate bearing capacity of the soil when the tearing knife acts on the soil.

[0120] The horizontal cutting force and vertical thrust force are obtained by analyzing the forces acting on the tearing knife in the X and Y directions. The calculation is shown as follows:

[0121]

[0122] Among them, F H2 is the horizontal cutting force of the tearing knife, F V2 It is the vertical propulsion force of the tearing knife.

[0123] The tangential cutting force and vertical thrust force of the tool combination are further calculated and the calculation formula is as follows:

[0124] F H =F H1 +F H2 .

[0125] F V =F V1 +FV2 .

[0126] Among them, F H is the tangential cutting force, F V For vertical propulsion.

[0127] S5: In an exemplary embodiment, Figure 2 As shown, a cutting efficiency model is established based on the soil breaking volume model and the cutting force model; the cutting efficiency model is used to determine the cutting efficiency based on the total soil breaking volume and the cutting force; the cutting efficiency is the energy consumed by the cutter disc in cutting unit soil in one rotation cycle.

[0128] During the excavation process, the amount of earth broken by the shield cutterhead in one rotation cycle and the size of the tool cutting force are the direct reactions of the shield cutterhead tool during the excavation process. By establishing the earth breaking model and tool cutting force model respectively, the cutting efficiency of the tool combination is defined as the energy consumed by the cutterhead in cutting a unit of soil in one rotation cutting cycle. The definition of cutting efficiency is as follows:

[0129]

[0130] Where E is cutting efficiency, kJ / m 3 , F V is the vertical thrust, A is the cutting depth, N is the number of tools, n is the tool number, ρ n is the layout radius of the nth tool, F H is the tangential cutting force, and V is the total amount of ground broken.

[0131] S6: In an exemplary embodiment, Figure 3 As shown, according to the cutting efficiency model, the cutting efficiency under different tool arrangement parameters is determined, and the tool arrangement parameters with the highest cutting efficiency are taken as the optimal arrangement scheme.

[0132] Based on the obtained ground breaking amount and cutting force results, the cutting efficiency results under different combination layout parameters are obtained by substituting them into the cutting efficiency model, and then the optimal tool combination layout parameters are obtained.

[0133] The present application provides a method for optimizing the arrangement of tools for a slurry shield cutter disc. The method is aimed at the complex working conditions of long construction distances and large excavation surfaces in large-diameter slurry shield projects, and at the engineering problem of low shield excavation efficiency. The method aims to improve the excavation efficiency of the slurry shield cutter disc, and provides an optimal arrangement method for the tearing knives and cutting knives of the slurry shield cutter disc from the perspective of the arrangement of the tool combination.

[0134] This application is in line with engineering practice, giving priority to the synergy between the tearing knife and the cutting knife during the excavation process, making the model closer to reality. On the other hand, the amount of soil broken and the cutting force are the direct results of the front cutter in cutting the soil. The cutting efficiency model in this application fully combines the amount of soil broken and the cutting force model, which can effectively evaluate the layout scheme under different tool combination layout parameters, ensuring the effectiveness of the cutting efficiency model.

[0135] The cutting force model of the present application is based on the tillage tool cutting resistance model established by McKyes-Ali, which divides the failure zone of the soil into a central failure zone and two side semi-lunar failure zones. However, according to the investigation object of the soil breaking volume model, the side semi-lunar failure zone with little influence and complex calculation is ignored. Overall, the cutting efficiency calculation model is a mathematical theoretical model based on theoretical derivation and combined with engineering practice. It is superior to other optimization methods in terms of calculation efficiency, has high calculation efficiency, and is suitable for a variety of mud and water cutter disc tearing knives and cutting knife tool combination arrangements.

[0136] In an exemplary embodiment, a cutter optimization arrangement system for a slurry shield cutter head is provided, comprising:

[0137] The parameter acquisition module is used to obtain the structural parameters and working conditions of the front tool; the front tool includes: a cutting tool and a tearing tool; the structural parameters of the front tool include: tool width, tool thickness and cutting angle; the working conditions include: geological conditions and tool disc size.

[0138] The arrangement parameter determination module is used to determine the tool arrangement parameters according to the front tool structure parameters and the working conditions; the tool arrangement parameters include: the number of tools, the range of overlap and the radius range of the arrangement area.

[0139] The ground breaking volume model establishment module is used to establish a ground breaking volume model of the tool combination according to the cutting process of the tool and the tool arrangement parameters; the ground breaking volume model is used to determine the total ground breaking volume of the tool.

[0140] The cutting force model establishment module is used to establish a cutting force model of the tool combination based on the Rankine passive earth pressure theory, the tillage tool cutting resistance model, and the synergy and cutting mechanism of the tool; the cutting force model is used to determine the cutting force of the tool; the cutting force includes: tangential cutting force and vertical thrust force.

[0141] The cutting efficiency model establishment module is used to establish a cutting efficiency model based on the soil breaking volume model and the cutting force model; the cutting efficiency model is used to determine the cutting efficiency based on the total soil breaking volume and the cutting force; the cutting efficiency is the energy consumed by the cutter disc in cutting unit soil in one rotation cycle.

[0142] The arrangement scheme determination module is used to determine the cutting efficiency under different tool combination arrangement parameters according to the cutting efficiency model, and take the tool arrangement parameters with the highest cutting efficiency as the optimal arrangement scheme.

[0143] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0144] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for optimizing the arrangement of cutters of a slurry shield cutter head, characterized in that: The cutter optimization arrangement method of the slurry shield cutter head comprises: Obtaining the structural parameters and working conditions of the front cutter; the front cutter includes: a cutting cutter and a tearing cutter; the structural parameters of the front cutter include: cutter width, cutter thickness and cutting angle; the working conditions include: geological conditions and cutter disc size; Determine tool arrangement parameters according to the front tool structure parameters and the working conditions; the tool arrangement parameters include: the number of tools, the range of overlap, and the radius range of the arrangement area; According to the cutting process of the tool and the tool arrangement parameters, a ground breaking volume model of the tool combination is established; the ground breaking volume model is used to determine the total ground breaking volume of the tool; According to Rankine's passive earth pressure theory, based on the tillage tool cutting resistance model, combined with the tool synergy and cutting mechanism, a cutting force model of the tool combination is established; the cutting force model is used to determine the cutting force of the tool; the cutting force includes: tangential cutting force and vertical thrust force; A cutting efficiency model is established according to the soil breaking volume model and the cutting force model; the cutting efficiency model is used to determine the cutting efficiency according to the total soil breaking volume and the cutting force; the cutting efficiency is the energy consumed by the cutter disc in cutting a unit of soil in one rotation cycle; According to the cutting efficiency model, the cutting efficiency under different tool combination layout parameters is determined, and the tool layout parameters with the highest cutting efficiency are taken as the optimal layout scheme.

2. The method for optimizing the arrangement of cutters of a slurry shield cutterhead according to claim 1, characterized in that: The number of the cutting knives and the tearing knives is the same as the radius of the arrangement area.

3. The method for optimizing the arrangement of cutters of a slurry shield cutterhead according to claim 1, characterized in that: According to the front tool structure parameters and the working conditions, tool arrangement parameters are determined, specifically including: Using the formula Determine the number of tools; where N is the number of tools, ρ max is the maximum layout radius of the tool, ρ0 is the minimum layout radius of the tool, and b1 is the cutter width; Using the formula With formula Determine the minimum and maximum overlap of the cutter; the overlap range of the cutter is a min <a<a max ; Among them, a min is the minimum overlap of the cutter, b1 is the width of the cutter, ρ max is the maximum layout radius of the tool, ρ1 is the layout radius of the first tool, n is the tool number, a max is the maximum overlap of the cutter, a is the cutting overlap of the cutter; Using the formula ρ n =ρ1+(n-1)(b1-a) determines the layout radius of the nth tool; where ρ n is the layout radius of the nth tool, n is the tool number, and b1 is the cutter width.

4. The method for optimizing the arrangement of cutters of a slurry shield cutterhead according to claim 1, characterized in that: According to the cutting process of the tool and the tool arrangement parameters, a model of the earth breaking volume of the tool combination is established, which specifically includes: The soil breaking model is determined using the formula V=V1+V2; where V1 is the soil breaking amount of the cutter, N is the number of tools, n is the tool number, b1 is the width of the cutting tool, b2 is the thickness of the tearing tool, A is the cutting depth, ρ n is the layout radius of the nth tool, V2 is the amount of soil broken by the tearing tool, H is the height difference between the cutting knife and the tearing knife, and V is the total amount of soil broken.

5. The method for optimizing the arrangement of cutters of a slurry shield cutterhead according to claim 1, characterized in that: According to Rankine's passive earth pressure theory, based on the tillage tool cutting resistance model, combined with the tool synergy and cutting mechanism, the cutting force model of the tool combination is established, including: Using formula F H =F H1 +F H2 and formula F V =F V1 +F V2 Establish cutting force model of tool combination; Among them, F H is the tangential cutting force, F H1 F is the horizontal cutting force of the cutter, H1 =P H1 +μp u1 (b1-b2-a)l1 P H1 is the tangential reaction force of the cutting soil on the cutter, μ is the friction coefficient, and p u1 is the ultimate bearing capacity of the soil when the cutter acts on the soil, b1 is the width of the cutter, b2 is the thickness of the tearing knife, a is the overlap of the cutter cutting, l1 is the arc projection width of the cutter blade, and F H2 is the horizontal cutting force of the tearing knife, F H2 =P H2 +μp u2 b2l2,P H2 is the tangential reaction force of the cutting soil on the tearing knife, μ is the friction coefficient, and p u2 is the ultimate bearing capacity of the soil when the tearing knife acts on the soil, b2 is the thickness of the tearing knife, l2 is the arc projection width of the tearing knife blade, and F V is the vertical thrust, F V1 F is the vertical thrust of the cutter, V1 =p u1 (b1-b2-a)l1-P V1 , P V1 F is the vertical reaction force of the cutting soil on the cutter, V2 is the vertical propulsion force of the tearing knife, F V2 =p u2 b2l2-P V2 , P V2 It is the vertical reaction force of the cutting soil on the tearing knife.

6. The method for optimizing the arrangement of cutters of a slurry shield cutterhead according to claim 1, characterized in that: A cutting efficiency model is established based on the soil breaking volume model and the cutting force model, specifically including: Using the formula Establish a cutting efficiency model; where E is the cutting efficiency, F V is the vertical thrust, A is the cutting depth, N is the number of tools, n is the tool number, ρ n is the layout radius of the nth tool, F H is the tangential cutting force, and V is the total amount of ground broken.

7. A tool optimization arrangement system for a slurry shield cutter head, characterized in that: The tool optimization arrangement system of the slurry shield cutter head includes: The parameter acquisition module is used to acquire the structural parameters and working conditions of the front cutter; the front cutter includes: a cutting cutter and a tearing cutter; the structural parameters of the front cutter include: cutter width, cutter thickness and cutting angle; the working conditions include: geological conditions and cutter disc size; An arrangement parameter determination module is used to determine the arrangement parameters of the cutters according to the front cutter structure parameters and the working conditions; the arrangement parameters of the cutters include: the number of cutters, the range of overlap, and the radius range of the arrangement area; A ground breaking volume model establishment module is used to establish a ground breaking volume model of a tool combination according to the cutting process of the tool and the tool arrangement parameters; the ground breaking volume model is used to determine the total ground breaking volume of the tool; The cutting force model establishment module is used to establish a cutting force model of the tool combination based on the Rankine passive earth pressure theory and the tillage tool cutting resistance model, combined with the synergy and cutting mechanism of the tool; the cutting force model is used to determine the cutting force of the tool; the cutting force includes: tangential cutting force and vertical thrust force; A cutting efficiency model establishment module is used to establish a cutting efficiency model according to the soil breaking volume model and the cutting force model; the cutting efficiency model is used to determine the cutting efficiency according to the total soil breaking volume and the cutting force; the cutting efficiency is the energy consumed by the cutter disc in cutting a unit of soil in one rotation cycle; The arrangement scheme determination module is used to determine the cutting efficiency under different tool combination arrangement parameters according to the cutting efficiency model, and take the tool arrangement parameters with the highest cutting efficiency as the optimal arrangement scheme.

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