Design method of passive icebreaking cutter tooth carrier suitable for high-adhesion frozen ice

Abstract

The invention relates to the technical field of road maintenance machinery, in particular to a design method of a passive icebreaking cutter tooth carrier suitable for high-adhesion frozen ice, which comprises the following steps: acquiring key characteristic parameters of the high-adhesion frozen ice; selecting and designing cutter tooth materials, forms and key geometric parameters according to the characteristics of the high-adhesion frozen ice; simulating the icebreaking process of a single cutter tooth by adopting a finite element method and extracting an effective breaking range; designing the diameter and circumferential layout of a cutter tooth carrier based on the icebreaking range and the chip removal constraint; determining the length and the axial layout of the carrier according to road specifications and structural constraints; and carrying out wall thickness design and strength check based on the dynamic load. According to the method, through systematic steps, the special cutter tooth carrier for high-adhesion frozen ice is designed, and the method has the advantages that the design process is standardized, the research and development period is short, and the cost is low.

Description

A design method for a passive icebreaking serrated vehicle suitable for highly adhesive ice. Technical Field

[0001] This invention relates to the field of road maintenance machinery technology, and in particular to a design method for a passive ice-breaking toothed vehicle suitable for highly adhesive ice. Background Technology

[0002] Winter road icing is a serious global problem affecting traffic safety. In my country, this problem exhibits significant regional differences due to its vast geographical span and complex climatic conditions. In particular, the central and southern regions of my country frequently experience low temperatures, rain, snow, and freezing weather in winter. Rain, frost, fog, and wet snow repeatedly freeze and thaw, forming road icing. This type of road icing has strong adhesion and an uneven surface. It is not only highly hazardous but also fundamentally different from the compacted snow icing in traditional northern regions, posing new challenges to ice-breaking technologies and equipment.

[0003] Currently, road de-icing mainly relies on two categories of technologies: de-icing agent methods and mechanical ice-breaking methods. De-icing agent methods lower the freezing point by spreading de-icing agents. While simple to operate, long-term use can corrode road surfaces and bridge structures, reducing their lifespan; it also pollutes groundwater and soil. Mechanical ice-breaking methods, on the other hand, are physical removal methods and are more environmentally friendly. Mainstream equipment such as roller brush and hammer ice breakers are designed and operate based on the conditions of loose snow, compacted snow, or brittle ice in northern regions, and have formed a relatively mature technological system.

[0004] However, directly applying existing mechanical icebreaking equipment to high-adhesion icing conditions has significant drawbacks and shortcomings: the gaps between the cutting teeth are prone to clogging, icebreaking efficiency is low, and core components fail prematurely due to mismatched impact loads. The root cause lies in the lack of quantitative research on high-adhesion icing in existing designs, and the absence of a comprehensive design methodology from understanding icing characteristics to equipment implementation. Specifically, icing characteristic input relies on general experience rather than measured data; the layout of the cutting teeth and their carrier is not precisely matched to the mechanical strength of the ice layer; and the structural design has not been verified against complex loads under regionally specific icing conditions. Therefore, a systematic design method for passive icebreaking cutting tooth carriers that combines simulation verification and multi-objective optimization for high-adhesion icing in central and southern regions is urgently needed to fill this gap in design methodology. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and propose a design method for a passive ice-breaking toothed vehicle suitable for highly adhesive road icing, which can efficiently design a dedicated high-performance passive ice-breaking toothed vehicle for highly adhesive road icing.

[0006] To achieve the above objectives, the present invention adopts the following specific technical solution: The passive icebreaker carrier design method for highly adhesive ice provided by the present invention includes the following steps: Step 1: Obtain the characteristic parameters of highly adhesive ice through in-situ field testing and laboratory calibration testing, including ice layer thickness, shear strength, interfacial bonding strength, compressive strength, and elastic modulus; Step 2: Based on the characteristic parameters of highly adhesive ice, select and design the icebreaker parameters, including icebreaker material selection, icebreaker shape selection, and icebreaker geometric parameter calculation; the icebreaker geometric parameter calculation includes establishing an icebreaker length calculation model, an optimization model for the tip angle and tip radius, and an icebreaker bending strength verification model; Step 3: The process of breaking ice with a single cutting tooth is simulated to obtain the effective breaking range. This includes constructing a simulation model based on the cutting tooth parameters obtained in step two and the high-adhesion ice-freezing characteristic parameters obtained in step one, setting the load conditions, boundary conditions, and solver settings, and analyzing the simulation results to obtain the effective breaking range. Step four involves designing the diameter of the cutting tooth carrier and the circumferential layout of the cutting teeth based on the effective breaking range of a single cutting tooth. This includes quantitatively defining the design constraints, establishing a mathematical model of the circumferential layout, and optimizing the solution. Step five involves designing the overall length of the cutting tooth carrier and the axial layout of the cutting teeth. This includes determining the total operating length of the cutting tooth carrier based on the operating scenario, segmenting the design based on the length-to-diameter ratio constraint, and designing the axial cutting tooth layout.

[0007] Step 6: Design and verification of the wall thickness of the cutter-tooth vehicle based on dynamic load, including verification criteria under mechanical modeling and calculation to determine the wall thickness. The verification criteria under mechanical modeling include maximum bending moment verification, torsional strength verification and stiffness verification.

[0008] Furthermore, in step two, the cutting edge shape is selected as blunt-tipped teeth or flat teeth with cutting edges; the length of the cutting edge... The calculation model is as follows: In the formula, The maximum thickness of the ice layer is measured in step one. To ensure a safe insertion margin, This is the expected wear allowance. For the thickness of the mounting base; tooth tip angle With tip radius The optimized model is: In the formula, This refers to the pressure at the tip of the blade. To estimate the penetration force; It is the equivalent tip diameter; This is an empirical coefficient, ranging from 1.5 to 2.0; The compressive strength of ice; the bending strength verification model for the knife teeth is: ; In the formula, This represents the maximum bending stress borne by the root of the cutting tooth. This represents the maximum ice-breaking force of a single blade. This represents the average shear strength of the ice layer. The effective shearing area of ​​the cutting teeth; The diameter at the root of the blade teeth; This represents the allowable stress of the material.

[0009] Further, in step three, the simulation model construction includes establishing a cutting tooth model based on the cutting tooth parameters from step two, establishing a high-adhesion ice-freezing model based on the high-adhesion ice-freezing characteristic parameters from step one, setting automatic surface-to-surface contact between the cutting tooth and the ice surface, and setting the friction coefficient; the load condition is to apply a vertically downward displacement load to the cutting tooth to simulate the extreme condition of breaking ice solely by the vehicle's own weight; the boundary condition is to completely constrain all degrees of freedom of the bottom surface of the ice layer to simulate the firm adhesion between the ice and the road surface; constrain the normal displacement of the ice layer's side surface, allowing free contraction; the solver uses an explicit dynamic solver to handle large deformation, material failure, and contact separation, and sets the total computation time to ensure that the cutting tooth can completely penetrate the ice layer; the simulation result analysis process is as follows: through the equivalent plastic strain cloud map and material state cloud map, the entire process of the ice layer from microcrack initiation, propagation, to complete breakage is dynamically observed; the effective breakage width W is obtained as follows: at the end of the simulation, the maximum projected width of the area in the ice layer where the material has completely failed on a plane perpendicular to the direction of cutting tooth movement is measured, which is the effective breakage width W of a single tooth.

[0010] Furthermore, in step four, the quantitative definition of design constraints includes the minimum chip removal space. and minimum ice-breaking coverage Minimum chip removal space To prevent ice and debris from clogging between adjacent cutting teeth, a minimum distance must be maintained between the roots of adjacent cutting teeth; minimum ice-breaking coverage. To ensure sufficient overlap of the breaking zones of adjacent cutting teeth and eliminate unbroken ice bands, the minimum overlap rate that adjacent cutting teeth must achieve is required. The constraints of the mathematical model for the circumferential layout include chip removal space constraints and ice-breaking coverage constraints. The chip removal space constraint is the arc length allocated to each cutting tooth, which should be greater than or equal to the width occupied by the cutting tooth itself plus the minimum chip removal gap it requires, expressed as follows: In the formula, This is the maximum width at the root of the cutting teeth; The target is the vehicle diameter; N is the number of circumferential cutting teeth; the ice-breaking coverage constraint is that the total effective breaking width of N cutting teeth should be greater than or equal to the circumference length that the vehicle needs to cover, and there should be overlap that satisfies the minimum ice-breaking coverage, as expressed below: In the formula, W is the effective breaking width of a single tooth. The optimization solution process is as follows: Determine the minimum theoretical diameter, solve the two constraint inequalities of chip removal space constraint and ice breaking coverage constraint, eliminate N, and the lower limit condition that the carrier diameter D must satisfy can be obtained; determine the number of circumferential cutting teeth, substitute the selected initial diameter D into the ice breaking coverage constraint formula, and calculate the required minimum theoretical number of teeth; substitute the calculated minimum theoretical number of teeth into the chip removal space constraint formula for verification. If it is satisfied, it is a feasible solution; if it is not satisfied, increase the diameter D or increase the number of teeth N, perform iterative optimization, and re-verify until both are satisfied.

[0011] Furthermore, in step five, the total working length of the serrated vehicle is determined based on the operational scenario as follows: The minimum required working width is determined according to the standard road width. Calculate the total length of the vehicle: the total working length of the serrated vehicle. Need to be greater than To ensure complete coverage in a single pass, that is: In the formula, To ensure ice-breaking performance at the lane edges, a single-sided coverage margin is provided. The segmented design, based on aspect ratio constraints, includes bending stiffness and deformation control, and dynamic stability criteria, as detailed below: Bending stiffness and deformation control: The cutter-tooth carrier functions as a beam bearing distributed loads during operation, where the maximum deflection f is related to the axial length of a single cutter-tooth carrier segment. It is directly proportional to the fourth power of the value and inversely proportional to the fourth power of the diameter D. Its relative deflection, i.e., the ratio of deformation to length, mainly depends on the aspect ratio. When the value is too large, the stiffness will drop sharply, and the cutting tooth carrier will be more prone to bending and deformation, resulting in uneven cutting depth of the cutting teeth and affecting the crushing effect; Dynamic stability criterion: To avoid the operating speed from approaching the first-order critical speed. To induce resonance, the first-order critical speed of the cutting tooth carrier needs to be much higher than its operating speed. If the segment is too large, the critical speed will be too low, making it difficult to design a drive system that meets the ice-breaking linear speed requirements while staying away from the resonance zone. Combining bending stiffness and deformation control with dynamic stability criteria, an allowable length-to-diameter ratio is set. The theoretical minimum number of segments is Where ceil is the floor function; the axial cutter tooth layout design is as follows: the cutters are arranged at equal intervals along the axial direction, and the phase angle of each column of cutters in the circumferential direction is consistent with that of the adjacent column of cutters, forming a regular grid arrangement. Along the axial direction of the vehicle, the effective breaking zones of any two adjacent columns of cutters must overlap to avoid leaving unbroken ice bands. Therefore, the axial spacing... Calculation formula: In the formula, W is the effective breaking width of a single tooth. This represents the minimum ice-breaking coverage rate.

[0012] Furthermore, in step six, the mechanical modeling verification criterion treats the single-segment cutter-tooth vehicle as a simply supported beam supported by bearings at both ends, and the maximum bending moment verification is as follows: Calculate the uniformly distributed load. m is the estimated total weight of the serrated vehicle. For the length of the cutting teeth, the maximum bending moment is... : Introducing dynamic load factor The design bending moment used for strength verification is obtained. Bending normal stress ;in, Section modulus for bending; ; The moment of inertia of the cylinder section, It is the distance from the neutral axis to the outermost edge of the cross section, i.e., the lever arm of the point of maximum stress; The average radius of the cylinder; The wall thickness of the cylinder; stiffness check: ; Given the allowable stress of the material of the knife-tooth carrier, the wall thickness is... : Torsional strength verification is as follows: traction resistance ;r represents the horizontal traction resistance that the icebreaker needs to overcome per meter of working width. This is determined in step one, and the basic torque is... Due to the presence of impact loads in actual operations, a dynamic load factor is introduced. ; Obtain the design torque used for strength verification Shear stress ; For torsional section modulus, strength condition: ; Let the allowable shear stress of the material of the knife-tooth carrier be the wall thickness. : The stiffness check is as follows: The differential equation of the deflection curve of a simply supported beam under uniformly distributed load is: E is the elastic modulus. The maximum deflection is obtained by integrating the boundary conditions, i.e., the deflection w=0 at both ends and the bending moment M=0. It happened in the middle Location: Stiffness condition: ; For allowable deflection, the wall thickness is... The process of calculating and determining the wall thickness is as follows: Under the conditions of satisfying the maximum bending moment check, torsional strength check, and stiffness check, the minimum theoretical wall thickness is determined by solving the problem. Considering the minimum process wall thickness Increased allowance for wear and corrosion Determine the final wall thickness : Then Round it upwards to the closest standard steel plate thickness.

[0013] This invention achieves the following technical effects: It obtains the typical physical and mechanical properties of highly adhesive ice in central and southern Taiwan through in-situ testing and laboratory calibration. Based on these properties, it selects the material and shape of the cutting teeth, calculates key geometric parameters, and verifies strength under corresponding working conditions. It models the cutting teeth and ice parameters, and uses the finite element method to simulate the ice-breaking process of a single cutting tooth and extract its effective breaking range. Under constraints of chip removal space and ice-breaking coverage, it designs the diameter of the cutting tooth carrier and the circumferential layout of the cutting teeth based on the ice-breaking range of a single cutting tooth. It determines the total length based on the working scenario and designs the assembly of the cutting tooth carrier length and the axial layout of the cutting teeth based on the aspect ratio constraint. The cutting tooth carrier is verified under mechanical modeling, and the wall thickness that meets engineering decisions is calculated. This invention summarizes the design process into six logically rigorous steps, forming a standardized and scalable design process and method. Using this method, a dedicated, high-performance passive ice-breaking blade vehicle can be efficiently designed for roads with high adhesion in central and southern regions, greatly shortening the research and development cycle and reducing trial and error costs. Attached Figure Description

[0014] Figure 1 is a flowchart illustrating the design method of a passive icebreaker carrier suitable for highly adhesive ice condensation according to an embodiment of the present invention. Detailed Implementation

[0015] In the following description, embodiments of the invention will be described with reference to the accompanying drawings. In the description below, the same modules are denoted by the same reference numerals. Where the same reference numerals are used, their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0017] This invention provides a design method for a passive ice-breaking blade carrier suitable for high-adhesion ice, comprising the following steps: Step 1: Obtaining key characteristic parameters of high-adhesion ice. Typical snow and ice disaster-prone areas in central and southern my country (such as mountainous highways, bridges, and shaded road sections in Hubei, Hunan, and Jiangxi provinces) are selected as target areas. Sampling time is set during winter when temperatures fluctuate between 0℃ and -5℃, accompanied by freezing rain or frost. Step 2: Selecting and designing key parameters of the blades based on the characteristics of high-adhesion ice. Step 3: Simulating the ice-breaking process of a single blade and verifying its effective breaking range using the finite element method. Step 4: Designing the diameter of the blade carrier and the circumferential layout of the blades based on the ice-breaking range of a single blade. Step 5: Designing the overall length of the blade carrier and the axial layout of the blades based on my country's "Urban Road Engineering Design Code," "Highway Engineering Technical Standards," and "Regulations on the Management of Oversized and Overweight Vehicles on Highways," along with structural constraints. Step 6: Designing and verifying the wall thickness of the blade carrier based on dynamic loads.

[0018] The method of the present invention will be described below with reference to specific embodiments.

[0019] Step 1: Obtain the characteristic parameters of high-adhesion ice through on-site in-situ testing and laboratory calibration testing, including ice layer thickness, shear strength, interfacial bonding strength, compressive strength, and elastic modulus.

[0020] (1) On-site in-situ testing was conducted using an ultrasonic thickness gauge, which was perpendicular to the ice surface. Multiple measurements were taken and the thickness distribution was recorded. The maximum value was taken as the maximum thickness, and the arithmetic mean was taken as the average thickness.

[0021] Using a portable vane shear tester, a standard vane probe is pressed vertically into the ice layer at a uniform speed until the ice layer undergoes torsional failure. The maximum torque value is recorded using the instrument, and the shear strength at that point is calculated based on the probe's geometric dimensions. The test is repeated three times at each point, and the average value is taken.

[0022] Using a portable pull-out apparatus, a standard-sized metal test head is bonded to the ice surface with a low-temperature curing high-strength adhesive. After the adhesive has fully cured, the pull-out head is pulled vertically upward at a constant rate. The maximum tensile force value is recorded and divided by the bonding area of ​​the test head to obtain the interfacial bonding strength.

[0023] Using a portable hollow drill, a complete cylindrical ice core was drilled. After the ice core was removed, it was immediately placed in a pre-cooled, insulated storage box, and the sampling location and ambient temperature were recorded.

[0024] (2) The laboratory calibration test uses the geometric measurement-mass method to calculate the density of the ice sample.

[0025] The uniaxial compression test method was used. The ice sample was processed into a standard cylinder and loaded with a constant strain rate at a set temperature. The peak stress was read from the obtained stress-strain curve as the compressive strength, and the slope of the linear segment was used as the elastic modulus.

[0026] The sampling direct shear test method involves applying a constant normal stress to an ice sample and then shearing it. By using a set of shear strength results under different normal stresses, the Mohr-Coulomb failure envelope is fitted, and the intercept is the cohesive force, while the slope angle is the internal friction angle.

[0027] The indirect tensile strength determination method is adopted. The ice sample is processed into a disk, and a compressive load is applied along the diameter direction. The indirect tensile strength of the ice is calculated from its failure load using classical elastic theory formulas.

[0028] Step 2: Based on the characteristic parameters of high-adhesion ice, select and design the parameters of the cutting teeth, including the selection of cutting tooth materials, the selection of cutting tooth shape, and the calculation of cutting tooth geometric parameters; the calculation of cutting tooth geometric parameters includes establishing a cutting tooth length calculation model, an optimization model for tooth tip angle and tip radius, and a cutting tooth bending strength verification model.

[0029] (1) Selection of cutting tooth material: Based on the measured range of compressive strength of ice layer, the hardness of the working surface of the cutting tooth must be significantly higher than the hardness of ice.

[0030] The ice-breaking process involves impact loads. According to dynamic analysis, the cutting teeth need to absorb impact energy to avoid brittle fracture.

[0031] Considering the cost of large-scale applications, high-cost materials were excluded, and medium- and low-carbon alloy steels that can meet performance requirements through surface strengthening treatment were selected.

[0032] Based on the above criteria, medium-carbon low-alloy structural steel (such as 37CrMo and 35CrMn) was identified as the preferred material.

[0033] (2) Selection of blade shape: The roads in the central and southern regions have high adhesion ice and ice that has been repeatedly frozen and thawed and have high non-uniformity. When breaking it, it is necessary to overcome its brittleness and adhesion. The blade shape should be blunt-tipped or flat-toothed.

[0034] (3) Calculation of key geometric parameters of the cutting teeth: cutting tooth length The calculation model is as follows: In formula (1), The maximum thickness of the ice layer is measured in step one. To ensure a safe insertion margin, allow for 10–15 mm. The expected wear allowance is 5–8 mm; The thickness of the mounting base should be 15–20 mm.

[0035] Tooth tip angle With tip radius Optimization model (specific pressure requirement): (2) In the formula, This refers to the pressure at the tip of the cutting teeth; To estimate the penetration force; The equivalent tip diameter (and) and (Related) This is an empirical coefficient, ranging from 1.5 to 2.0; The compressive strength of ice. The stress concentration factor at the tooth tip must be lower than the fatigue limit of the material, and under the condition of satisfying the specific pressure, the tip radius r should be maximized to improve wear resistance, while the apex angle β should be minimized (but not less than 60°) to ensure penetration capability.

[0036] The bending strength verification model for the knife teeth is as follows: (3) (4) In the formula, This represents the maximum bending stress borne by the root of the cutting tooth. This represents the maximum ice-breaking force of a single blade. This represents the average shear strength of the ice layer. The effective shearing area of ​​the cutting teeth; The diameter at the root of the blade teeth; This represents the allowable stress of the material.

[0037] Step 3: Simulate the ice-breaking process of a single blade to obtain the effective breaking range. This includes building a simulation model based on the blade parameters obtained in Step 2 and the high-adhesion ice-freezing characteristic parameters obtained in Step 1, setting the load conditions, boundary conditions and solver settings, and analyzing the simulation results to obtain the effective breaking range.

[0038] (1) Construction of simulation model: Geometric modeling: Based on the key geometric parameters of the blade teeth output in step two, a three-dimensional solid model is established. The ice layer model is a cuboid, and its thickness dimension is taken as the maximum value measured in step one. The plane dimension is large enough to eliminate the boundary effect.

[0039] Cutter tooth material model: an isotropic linear elastic model, whose elastic modulus and Poisson's ratio are set according to the selected material.

[0040] Refreezing ice material model: The Coulomb-Mohr fracture criterion was adopted. The elastic modulus, compressive strength, tensile strength, and shear strength parameters were obtained from the test data in step one.

[0041] Contact and friction settings: Define automatic surface-to-surface contact between the blade teeth and the ice surface. The coefficient of friction is set to 0.1–0.3 based on literature values.

[0042] Mesh generation: Local mesh refinement is performed on the tip of the blade, the cutting edge, and the area where ice is expected to be damaged.

[0043] (2) Load, boundary conditions and solution settings Boundary conditions: Completely constrain all degrees of freedom of the bottom surface of the ice layer to simulate the firm bond between the ice and the road surface; constrain the normal displacement of the side of the ice layer to allow it to contract freely.

[0044] Loading conditions: Apply a vertically downward displacement load to the cutting teeth to simulate the extreme condition of breaking ice by the vehicle's own weight alone.

[0045] Solver settings: Select an explicit dynamics solver, such as ANSYS LS-DYNA, to efficiently handle large deformations, material failures, and contact separation. Set an appropriate total computation time to ensure the cutter teeth can completely penetrate the ice layer.

[0046] (3) Simulation result analysis and extraction of effective fracture range: Simulation result analysis: Through equivalent plastic strain cloud map and material state cloud map, the entire process of ice layer from microcrack initiation, expansion to complete fracture is dynamically observed.

[0047] Extraction of effective breaking width W: At the end of the simulation, the maximum projected width of the area in the ice layer where the material has completely failed is measured on a plane perpendicular to the direction of tooth movement. This is the effective breaking width W of a single tooth.

[0048] Step 4: Design the diameter of the blade carrier and the circumferential layout of the blades based on the effective ice-breaking range of a single blade, including the quantitative definition of design constraints, the establishment of a mathematical model of the circumferential layout, and optimization solution.

[0049] (1) Quantitative definition of design constraints: minimum chip removal space To prevent ice and debris from clogging between adjacent cutting teeth, a minimum distance must be defined between the roots of adjacent cutting teeth. This value is typically set to half of the effective breaking width W obtained in step three.

[0050] Minimum ice-breaking coverage To ensure sufficient overlap of the breaking zones of adjacent cutting edges and eliminate any unbroken ice bands, the minimum overlap rate that the breaking ranges of adjacent cutting edges must achieve is required. This value is based on the fact that the diffusion range of the breaking zone of tough ice in the central and southern regions is small, requiring a positive deviation (+1% to +3%) to ensure coverage.

[0051] (2) Establishing a mathematical model for the circumferential layout. Constraint 1: Chip removal space constraint. The arc length allocated to each cutting tooth must be greater than or equal to the width occupied by the cutting tooth itself plus the minimum chip removal clearance it requires. Expression: (5) In the formula, denoted as the maximum width at the root of the cutting teeth (from the design output of step two); D is the diameter of the vehicle to be determined; N is the number of circumferential cutting teeth to be determined.

[0052] Constraint 2: Icebreaking Coverage Constraint. The total effective breaking width of N blades must be greater than or equal to the circumference length that the vehicle needs to cover, and there must be overlap that satisfies the minimum icebreaking coverage rate. Expression: (6) In the formula, W is the effective breaking width of a single tooth (from the simulation output of step three).

[0053] (3) Optimize the solution to determine the minimum theoretical diameter. Combine the two constraint inequalities of chip removal space constraint and ice breaking coverage constraint, eliminate N, and the lower limit condition that the vehicle diameter D must satisfy can be obtained.

[0054] Determine the number of circumferential cutter teeth, substitute the selected initial diameter D into the ice-breaking coverage constraint formula, and calculate the minimum theoretical number of teeth required.

[0055] The calculated minimum theoretical number of teeth Substitute the chip removal space constraint formula for verification. If it is satisfied, it is a feasible solution. If it is not satisfied, increase the diameter D or increase the number of teeth N, perform iterative optimization, and re-verify until both are satisfied.

[0056] Step 5: Perform assembly design for the length of the cutting tooth carrier and the axial layout of the cutting teeth, including determining the total working length of the cutting tooth carrier based on the working scenario, performing segmented design based on the length-to-diameter ratio constraint, and designing the axial cutting tooth layout.

[0057] (1) Method for determining the total length based on the work scenario: Determine the minimum working width required based on the standard road width in the "Urban Road Engineering Design Code" and "Highway Engineering Technical Standard". .

[0058] Calculate the total length of the vehicle: the total working length of the serrated vehicle Slightly larger To ensure complete coverage in a single pass, that is: In formula (7), To ensure the ice-breaking effect at the edge of the lane, a 0.15 to 0.25m margin is typically provided for single-sided coverage.

[0059] (2) Segmentation method based on aspect ratio constraint. my country’s “Regulations on the Administration of Road Traffic for Oversized and Overweight Vehicles” clearly states that vehicles with a total width exceeding 2.55 meters need to apply for an oversized and overweight transport permit. However, ice-breaking equipment after being grouped can be transported through detachable parts or special trailers without the need for complicated oversized and overweight procedures. At the same time, in order to prevent the vehicle from causing excessive bending deformation or harmful vibration due to excessive length, aspect ratio is introduced as the core constraint for segmentation design.

[0060] Permissible aspect ratio Determination of bending stiffness and deformation control: When the cutter tooth carrier is in operation, it is equivalent to a beam bearing a distributed load, where the maximum deflection f is related to the axial length of a single cutter tooth carrier segment. It is directly proportional to the fourth power of the value and inversely proportional to the fourth power of the diameter D. Its relative deflection, i.e., the ratio of deformation to length, mainly depends on the aspect ratio. When the value is too large, the stiffness will drop sharply, and the cutting tooth carrier will be more prone to bending and deformation, resulting in uneven cutting depth of the cutting teeth and affecting the crushing effect; (8) Dynamic stability criterion: To avoid the operating speed from approaching the first-order critical speed. To induce resonance, the first-order critical speed of the cutting tooth carrier needs to be much higher than its operating speed. If the segment is too large, the critical speed will be too low, making it difficult to design a drive system that meets the ice-breaking linear speed requirements while staying away from the resonance zone. (9) Based on the bending stiffness and deformation control and dynamic stability criteria and engineering experience, set the allowable length-to-diameter ratio. .

[0061] The theoretical minimum number of segments is ;(10)where ceil is the floor function.

[0062] (3) Axial cutter tooth layout design method: The cutters are arranged at equal intervals along the axial direction, and the phase angle of each row of cutters is consistent with that of the adjacent row of cutters in the circumferential direction, forming a regular grid-like arrangement. Along the axial direction of the vehicle, the effective breaking zones of any two adjacent rows of cutters must overlap to avoid leaving unbroken ice bands. Therefore, the axial spacing... Calculation formula: (11) In the formula, W is the effective breaking width of a single tooth. This represents the minimum ice-breaking coverage rate.

[0063] Step 6: Design and verification of the wall thickness of the cutter-tooth vehicle based on dynamic load, including verification criteria under mechanical modeling and calculation to determine the wall thickness. The verification criteria under mechanical modeling include maximum bending moment verification, torsional strength verification and stiffness verification.

[0064] (1) The verification criteria under mechanical modeling treat the single-segment cutter tooth carrier as a simply supported beam supported by bearings at both ends.

[0065] 1) Maximum bending moment check: Calculate the uniformly distributed load (12) m is the estimated total weight of the serrated vehicle. For the length of the cutting teeth, the maximum bending moment is... ; (13) Introducing dynamic load factor The design bending moment used for strength verification is obtained. (14) Bending normal stress (15) Among them, Section modulus for bending; (16) The moment of inertia of the cylindrical section; It is the distance from the neutral axis to the outermost edge of the cross section, i.e., the lever arm of the point of maximum stress; The average radius of the cylinder; The wall thickness of the cylinder; stiffness check: (17) Given the allowable stress of the material of the knife-tooth carrier, the wall thickness is... : (18) 2) Torsional strength check: traction resistance (19) r is the horizontal traction resistance that the icebreaker needs to overcome per meter of working width. It is determined in step one, and the basic torque is... (20) Due to the presence of impact loads in actual operations, a dynamic load factor is introduced. : Obtain the design torque used for strength verification (21) Shear stress ;(twenty two) For torsional section modulus, strength condition: ;(twenty three) Let the allowable shear stress of the material of the knife-tooth carrier be the wall thickness. : (24) 3) Stiffness check: The differential equation of the deflection curve of a simply supported beam under uniformly distributed load is: (25) E is the elastic modulus. By integrating the boundary conditions, i.e., the deflection w=0 at both ends and the bending moment M=0, the maximum deflection is obtained. It happened in the middle Location: (26) Stiffness condition: (27) For allowable deflection, the wall thickness is... (28) (2) Calculation of wall thickness and engineering decision-making process: Solving for the minimum theoretical wall thickness: Solve the strength inequalities in 1), 2), and 3) to find the minimum theoretical wall thickness that satisfies all strength requirements. .

[0066] Minimum process wall thickness To ensure welding quality, roundness, and straightness, the allowance for rollers in construction machinery is typically no less than 12mm; considering wear and corrosion allowances, additional allowances are added based on expected lifespan and operating environment. It is usually 1 to 3 mm.

[0067] Determine the final wall thickness : (29) Engineering rounding: to make Round up to the nearest standard steel plate thickness, such as 14, 16, 18, or 20 mm.

[0068] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0069] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

[0070] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A design method for a passive ice-breaking serrated vehicle suitable for highly adhesive ice, characterized in that, The process includes the following steps: Step 1: Obtain the characteristic parameters of highly adhesive ice through in-situ testing and laboratory calibration, including ice thickness, shear strength, interfacial bonding strength, compressive strength, and elastic modulus; Step 2: Based on the characteristic parameters of highly adhesive ice, select and design the cutting tooth parameters, including cutting tooth material selection, cutting tooth shape selection, and cutting tooth geometric parameter calculation; the cutting tooth geometric parameter calculation includes establishing a cutting tooth length calculation model, a tooth tip angle and tip radius optimization model, and a cutting tooth bending strength verification model; Step 3: Simulate the ice-breaking process of a single cutting tooth to obtain the effective breaking range, including constructing a simulation model based on the cutting tooth parameters obtained in Step 2 and the highly adhesive ice characteristic parameters obtained in Step 1, and setting... The steps are as follows:

1. Load conditions, boundary conditions, and solver settings are configured, and simulation results are analyzed to obtain the effective breaking range; 2. Based on the effective ice-breaking range of a single cutter tooth, the diameter of the cutter tooth carrier and the circumferential layout of the cutter teeth are designed, including the quantitative definition of design constraints, the establishment of a mathematical model of the circumferential layout, and optimization solution; 3. The length of the cutter tooth carrier and the axial layout of the cutter teeth are designed as an assembly, including determining the total working length of the cutter tooth carrier based on the working scenario, segmented design based on the length-to-diameter ratio constraint, and axial cutter tooth layout design; 4. The wall thickness of the cutter tooth carrier is designed and verified based on dynamic loads, including verification criteria under mechanical modeling, calculation to determine the wall thickness, and verification criteria under mechanical modeling including maximum bending moment verification, torsional strength verification, and stiffness verification.

2. The design method for a passive icebreaking blade carrier suitable for highly adhesive ice as described in claim 1, characterized in that, In step two, the cutting edge shape should be either blunt-tipped or flat-edged; the cutting edge length... The calculation model is as follows: In the formula, The maximum thickness of the ice layer is measured in step one. To ensure a safe insertion margin, This is the expected wear allowance. For the thickness of the mounting base; tooth tip angle With tip radius The optimized model is: In the formula, This refers to the pressure at the tip of the blade. To estimate the penetration force; It is the equivalent tip diameter; This is an empirical coefficient, ranging from 1.5 to 2.0; The compressive strength of ice; the bending strength verification model for the knife teeth is: ； In the formula, This represents the maximum bending stress borne by the root of the cutting tooth. This represents the maximum ice-breaking force of a single blade. This represents the average shear strength of the ice layer. The effective shearing area of ​​the cutting teeth; The diameter at the root of the blade teeth; This represents the allowable stress of the material.

3. The design method for a passive icebreaking blade carrier suitable for highly adhesive ice as described in claim 1, characterized in that, In step three, the simulation model is constructed by establishing a cutting tooth model based on the cutting tooth parameters from step two, establishing a high-adhesion ice-freezing model based on the high-adhesion ice-freezing characteristic parameters from step one, setting automatic surface-to-surface contact between the cutting tooth and the ice surface, and setting the friction coefficient. The load condition is to apply a vertically downward displacement load to the cutting tooth to simulate the extreme condition of breaking ice solely by the vehicle's own weight. The boundary condition is to completely constrain all degrees of freedom of the bottom surface of the ice layer to simulate the strong adhesion between the ice and the road surface. The normal displacement of the ice layer's side is constrained, allowing free contraction. An explicit dynamic solver is selected to handle large deformation, material failure, and contact separation. The total computation time is set to ensure that the cutting tooth can completely penetrate the ice layer. The simulation results are analyzed by dynamically observing the entire process of the ice layer from microcrack initiation, propagation, to complete breakage through equivalent plastic strain cloud diagrams and material state cloud diagrams. The effective breakage width W is obtained by measuring the maximum projected width of the area in the ice layer where the material has completely failed at the end of the simulation on a plane perpendicular to the direction of cutting tooth movement. This is the effective breakage width W of a single tooth.

4. The design method for a passive icebreaking blade carrier suitable for highly adhesive ice as described in claim 1, characterized in that, In step four, the quantitative definition of design constraints includes the minimum chip removal space. and minimum ice-breaking coverage Minimum chip removal space To prevent ice and debris from clogging between adjacent cutting teeth, a minimum distance must be maintained between the roots of adjacent cutting teeth; minimum ice-breaking coverage. To ensure sufficient overlap of the breaking zones of adjacent cutting teeth and eliminate unbroken ice bands, the minimum overlap rate that adjacent cutting teeth must achieve is required. The constraints of the mathematical model for the circumferential layout include chip removal space constraints and ice-breaking coverage constraints. The chip removal space constraint is the arc length allocated to each cutting tooth, which should be greater than or equal to the width occupied by the cutting tooth itself plus the minimum chip removal gap it requires, expressed as follows: In the formula, This is the maximum width at the root of the cutting teeth; The target is the vehicle diameter; N is the number of circumferential cutting teeth; the ice-breaking coverage constraint is that the total effective breaking width of N cutting teeth should be greater than or equal to the circumference length that the vehicle needs to cover, and there should be overlap that satisfies the minimum ice-breaking coverage, as expressed below: In the formula, W is the effective breaking width of a single tooth; The optimization process is as follows: Determine the minimum theoretical diameter, solve the two constraint inequalities of chip removal space constraint and ice-breaking coverage constraint simultaneously, eliminate N, and the lower limit condition that the vehicle diameter D must satisfy can be obtained; determine the number of circumferential cutter teeth, substitute the selected initial diameter D into the ice-breaking coverage constraint formula, and calculate the required minimum theoretical number of teeth; substitute the calculated minimum theoretical number of teeth into the chip removal space constraint formula for verification. If it is satisfied, it is a feasible solution; if it is not satisfied, increase the diameter D or increase the number of teeth N, perform iterative optimization, and re-verify until both are satisfied.

5. The design method for a passive icebreaking blade carrier suitable for highly adhesive ice as described in claim 1, characterized in that, In step five, the total working length of the serrated vehicle is determined based on the operational scenario as follows: The minimum required working width is determined according to the standard road width. Calculate the total length of the vehicle: the total working length of the serrated vehicle. Need to be greater than To ensure complete coverage in a single pass, that is: In the formula, To ensure ice-breaking performance at the lane edge, a single-sided coverage margin is provided. The segmented design, based on aspect ratio constraints, includes bending stiffness and deformation control, and dynamic stability criteria, as detailed below: Bending stiffness and deformation control: The cutter-tooth carrier functions as a beam bearing a distributed load during operation, where the maximum deflection f is related to the axial length of a single cutter-tooth segment. It is directly proportional to the fourth power of the value and inversely proportional to the fourth power of the diameter D. Its relative deflection, i.e., the ratio of deformation to length, mainly depends on the aspect ratio. When the value is too large, the stiffness will drop sharply, and the cutting tooth carrier will be more prone to bending and deformation, resulting in uneven cutting depth of the cutting teeth and affecting the crushing effect; Dynamic stability criterion: To avoid the operating speed from approaching the first-order critical speed. To induce resonance, the first-order critical speed of the cutting tooth carrier needs to be much higher than its operating speed. If the segment is too large, the critical speed will be too low, making it difficult to design a drive system that meets the ice-breaking linear speed requirements while staying away from the resonance zone. Combining bending stiffness and deformation control with dynamic stability criteria, an allowable length-to-diameter ratio is set. The theoretical minimum number of segments is Where ceil is the floor function; the axial cutter tooth layout design is as follows: the cutters are arranged at equal intervals along the axial direction, and the phase angle of each column of cutters in the circumferential direction is consistent with that of the adjacent column of cutters, forming a regular grid arrangement. Along the axial direction of the vehicle, the effective breaking zones of any two adjacent columns of cutters must overlap to avoid leaving unbroken ice bands. Therefore, the axial spacing... Calculation formula: In the formula, W is the effective breaking width of a single tooth. This represents the minimum ice-breaking coverage rate.

6. The design method for a passive icebreaking blade carrier suitable for highly adhesive ice as described in claim 1, characterized in that, In step six, the mechanical modeling verification criterion treats the single-segment cutter-tooth vehicle as a simply supported beam supported by bearings at both ends. The maximum bending moment verification is as follows: Calculate the uniformly distributed load. m is the estimated total weight of the serrated vehicle. For the length of the cutting teeth, the maximum bending moment is... ； Introducing dynamic load factor The design bending moment used for strength verification is obtained. Bending normal stress ;in, Section modulus for bending; ； The moment of inertia of the cylinder section, It is the distance from the neutral axis to the outermost edge of the cross section, i.e., the lever arm of the point of maximum stress; The average radius of the cylinder; The wall thickness of the cylinder; stiffness check: ； Given the allowable stress of the material of the knife-tooth carrier, the wall thickness is... ： Torsional strength verification is as follows: traction resistance ;r represents the horizontal traction resistance that the icebreaker needs to overcome per meter of working width. This is determined in step one, and the basic torque is... Due to the presence of impact loads in actual operations, a dynamic load factor is introduced. : Obtain the design torque used for strength verification Shear stress ； For torsional section modulus, strength condition: ； Let the allowable shear stress of the material of the knife-tooth carrier be the wall thickness. ： The stiffness check is as follows: The differential equation of the deflection curve of a simply supported beam under uniformly distributed load is: E is the elastic modulus. The maximum deflection is obtained by integrating the boundary conditions, i.e., the deflection w=0 at both ends and the bending moment M=0. It happened in the middle Location: Stiffness condition: ； For allowable deflection, the wall thickness is... The process of calculating and determining the wall thickness is as follows: Under the conditions of satisfying the maximum bending moment check, torsional strength check, and stiffness check, the minimum theoretical wall thickness is determined by solving the problem. Considering the minimum process wall thickness Increased allowance for wear and corrosion Determine the final wall thickness ： Then Round it upwards to the closest standard steel plate thickness.

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