A method for constructing a test field uneven road surface

Abstract

The present application relates to the field of automobile technology, and more particularly to a method for constructing potholed road surface of a test field; comprising the following steps: step one: potholed road investigation of typical users; step two: potholed road parameter measurement; step three: potholed road parameter calculation; step four: potholed road surface generation; and step five: selection of typical potholed road; the technical scheme of the present application fills the gap of the method for constructing road surface of a test field of domestic manufacturers by means of scientific measurement method, calculation method and analysis method, and is close to the typical user scene in China.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automobile technology, in particular to a method for constructing a potholed road surface in a test field. BACKGROUND

[0002] In the past 30 years, due to the increasing global competition and the increasing requirements of users on product safety, durability and reliability, the vehicle industry has paid more attention to the quality, production capacity and reliability of its products. Therefore, the automobile products must be subjected to extensive and sufficient fatigue resistance design and test so as to quantify the dispersion of product strength and load in the process of reliability analysis.

[0003] A typical working condition that users often encounter in the process of daily driving is bad road. The damage phenomena of the existing asphalt pavement, sandy soil pavement and cement pavement usually include cracks, subsidence, push or wringing, potholes, oil overflow, potholes and the like, which sometimes appear alone and sometimes appear in several forms in a complex manner. Long-term driving of vehicles on bad roads will cause fatigue damage failure of parts, for example, surface blistering, scratching, bursting and wear of tires, deformation dislocation of pull rod ball head, damage and fracture of shock absorber, steering wheel deviation, suspension shaking and deformation, chassis damage, screw loosening and falling, and the like, and the body system will also produce white body cracking, interior and exterior decoration abnormal sound, door subsidence and the like.

[0004] In order to achieve the effects of simulating typical working conditions of users, strengthening examination, shortening verification period and reducing development cost, the vehicle manufacturing enterprises usually need to "concentrate" the relatively severe road surface of users and construct a strengthened bad road in the automobile test field according to a certain rule. The strengthened bad road is now an essential and important tool in the product development process of various automobile manufacturers. The existing domestic test field strengthened bad road usually borrows from foreign test field. The foreign test field strengthened bad road represents the typical bad road working condition of foreign users, which has a large difference from the typical working condition of Chinese actual users. How to determine the key parameters such as the size and density of the typical potholed road of users and how to construct the strengthened potholed road surface representing Chinese users are difficult problems faced by the industry at present. There are various specifications and types of user potholed roads. How to select the typical specifications, how to effectively combine them and how to meet the sufficient examination of user strength are difficult problems faced by the industry at present. SUMMARY

[0005] Therefore, the present application aims to solve the difficult problem of how to construct the strengthened potholed road surface representing Chinese users, so as to provide a method for constructing a potholed road surface in a test field.

[0006] A method for constructing a potholed road surface in a test field, comprising the following steps:

[0007] Step 1: Investigation of typical user potholed road;

[0008] Step two: pothole road parameter measurement;

[0009] Step three: pothole road parameter calculation;

[0010] Step four: pothole road generation;

[0011] Step five: selection of typical pothole road.

[0012] Further, the step one specifically includes:

[0013] (1) analyze the causes of pothole road formation;

[0014] (2) classify according to the characteristics of pothole road, which is divided into manhole cover pothole road and general pothole road;

[0015] (3) select typical road sections in typical areas.

[0016] Further, the step two specifically includes:

[0017] 2.1 Select the parameter pit of the pothole road to be measured and describe the pothole road with parameters, which are the diameter, depth and density of the pothole;

[0018] 2.2 Select measurement tools and methods, measure the geometric size of the pothole with height ruler and tape measure, wherein the height ruler is mainly used to measure the depth and radius of the pothole, and the tape measure is used to measure the length and width of the road surface;

[0019] 2.3 Measure and determine the parameter values in the field;

[0020] Further, the parameters are as follows:

[0021] 1) Depth and diameter of manhole cover: depth is 0.015m, 0.01m, 0.02m, 0.022m, 0.018m, 0.024m, 0.025m, 0.027m, 0.030m, a total of 9 sizes; diameter is 0.74m;

[0022] 2) Depth and diameter of general pothole road: depth is 0.08m, 0.12m, 0.13m, 0.15m, 0.18m, 0.2m, 0.24m, a total of 7 sizes; diameter is 0.2m, 0.3m, 0.4m, 0.5mm, a total of 3 sizes;

[0023] 3) Manhole cover density 0.5 / ㎡;

[0024] 4) General pothole road density: 1.2 / ㎡, 1.4 / ㎡, 1.8 / ㎡, 2 / ㎡, 2.5 / ㎡, 2.9 / ㎡, 3.3 / ㎡, 3.5 / ㎡, a total of 8 densities.

[0025] Further, the step three is specifically as follows:

[0026] 3.1 The depth of the manhole cover is classified, and the average value of each class is taken as the typical depth;

[0027] 3.2 The diameter of the manhole cover is not classified and the value is determined;

[0028] 3.3 The depth of the general pothole road is classified, and the average value of each class is taken as the typical depth;

[0029] 3.4 The diameter size of the general pothole road is determined;

[0030] 3.5 The general pothole density is classified, and the average value of each class is selected;

[0031] 3.6 The pothole road size is determined according to the size information obtained from steps 3.1-3.5.

[0032] Further, the depth of the manhole cover is classified into four classes: 0.01m-0.015m, 0.015m-0.02m, 0.02m-0.025m, 0.025m-0.03m; and the average value of each class is 0.0125m, 0.0175m, 0.0225m, 0.0275m respectively;

[0033] The diameter of the manhole cover is 0.74m;

[0034] The depth of the general pothole road is classified into four classes: 0.08m-0.12m, 0.12m-0.16m, 0.16m-0.2m, 0.2m-0.24m; and the average value of each class is 0.1m, 0.14m, 0.18m, 0.22m respectively;

[0035] The diameter of the general pothole road is classified into 0.2m, 0.35m, 0.5mm, a total of three sizes;

[0036] The general pothole density is classified into three classes, which are 1.2 / ㎡-2 / ㎡, 2 / ㎡-2.8 / ㎡, 2.8 / ㎡-3.6 / ㎡ respectively, and the average value of each class is 1.6 / ㎡, 2.4 / ㎡, 3.2 / ㎡ respectively;

[0037] The final determination of the manhole cover pothole road size includes:

[0038] Manhole cover 1: diameter 0.74m, depth 0.0125m; manhole cover 2: diameter 0.74m, depth 0.0175m; manhole cover 3: diameter 0.74m, depth 0.0225m; manhole cover 4: diameter 0.74m, depth 0.0275m;

[0039] The final determination of the general pit size includes:

[0040] Pit 1: diameter 0.2m, depth 0.1m; pit 2: diameter 0.3m, depth 0.1m; pit 3: diameter 0.3m, depth 0.14m; pit 4: diameter 0.4m, depth 0.1m; pit 5: diameter 0.4m, depth 0.14m; pit 6: diameter 0.4m, depth 0.18m; pit 7: diameter 0.4m, depth 0.22m; pit 8: diameter 0.5m, depth 0.1m; pit 9: diameter 0.5m, depth 0.14m; pit 10: diameter 0.5m, depth 0.18m; pit 11: diameter 0.5m, depth 0.22m.

[0041] Further, the fourth step specifically includes:

[0042] 4.1 According to the characteristics of the user's working conditions, at least two roads are designed on the test field, and the two roads respectively simulate the manhole cover pit road working condition and the general pit road working condition.

[0043] 4.2 According to the road surface design of the test field, the length and width of the manhole cover road and the length and width of the general pit road are determined; 4.3 The density of the manhole cover road and the density of the general pit road are respectively set;

[0044] 4.4 The number of pits of the manhole cover road and the number of pits of the general pit road are respectively calculated;

[0045] 4.5 At least three specifications of pits are set on the general pit road;

[0046] 4.6 The number of each kind of pit on the general pit road is calculated;

[0047] 4.7 The pits on the general pit road are arranged according to the principle of non-intersection and random distribution, each distribution is called a combination, and the road surface requires 100 different combinations to be generated.

[0048] Further, a total of four roads are designed on the test field, which are 1# pit road, 2# pit road, 3# pit road and 4# pit road; wherein the 1# pit road simulates the manhole cover pit road working condition, and the rest of the pit roads simulate the general pit road working condition;

[0049] The length of the 1# manhole cover road is 50m, and the width is 4m; the length of the 2# pit road is 100m, and the width is 4m; the length of the 3# pit road is 100m, and the width is 4m; the length of the 4# pit road is 100m, and the width is 4m;

[0050] The density of the 1# pit road is set to 0.5 / ㎡; the density of the 2# pit road is set to 1.6 / ㎡; the density of the 3# pit road is set to 2.4 / ㎡; the density of the 4# pit road is set to 3.2 / ㎡;

[0051] The 1# pit road is 200m2x0.5 / ㎡=100 pits; the 2# pit road is 400m2x1.6 / ㎡=640 pits; the 3# pit road is 400m2x2.4 / ㎡=960 pits; the 4# pit road is 400m2x3.2 / ㎡=1280 pits;

[0052] The 2# pit road is set to have pits 6, pits 8, pits 11, a total of 3 kinds of pits; the 3# pit road is set to include pits 2, pits 4, pits 7, a total of 3 kinds of pits; the 4# pit road is set to include pits 1, pits 3, pits 5, pits 10, a total of 4 kinds of pits;

[0053] The average number of each kind of pit in the 2# pit road is 640 / 3=213; the average number of each kind of pit in the 3# pit road is 960 / 3=320; the average number of each kind of pit in the 4# pit road is 1280 / 4=320;

[0054] The 2#, 3#, and 4# pit roads are arranged according to the principle of non-intersection and random distribution, and each distribution is called a combination. Each road surface requires 100 different combinations to be generated.

[0055] Further, the non-intersection judgment condition is that the distance between the centers is greater than the sum of the two radii.

[0056] Further, the specific content of step five is:

[0057] 5.1 According to the obtained multi-body dynamics model parameters of the whole vehicle, a whole vehicle dynamics model of the test vehicle is established in ADAMS / CAR;

[0058] 5.2 100 kinds of digital road surface models of the pit road are established in ADAMS / CAR;

[0059] 5.3 According to the established multi-body dynamics model of the whole vehicle and the digital test road surface model, a virtual test field analysis of the suspension system whole vehicle durability test is performed, and the whole vehicle model is virtually tested on the constructed digital road surface to obtain the wheel Z-direction force;

[0060] 5.4 The rainflow counting method and the Miner criterion are used to calculate the damage of the wheel Z-direction force to obtain the damage of the Z-direction force of the 100 kinds of pit roads;

[0061] 5.5 The obtained damage is arranged in order from small to large to obtain the damage value ranked 95th, which is recorded as the 95th percentile damage value;

[0062] 5.6 The road surface representing the 95th percentile damage value is selected as the final pit road.

[0063] The technical scheme of the present application fills the gap of the method for building a test field pavement in domestic manufacturers by scientific measurement method, calculation method and analysis method, and is close to the typical user scene in China. BRIEF DESCRIPTION OF DRAWINGS

[0064] In order to more clearly illustrate the technical scheme in the specific embodiments of the present application or the prior art, the drawings needed to be used in the specific embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0065] Figure 1 is a schematic view of a manhole cover 1;

[0066] Figure 2 is a schematic view of a manhole cover 2;

[0067] Figure 3 is a schematic view of a manhole cover 3;

[0068] Figure 4 is a schematic view of a manhole cover 4;

[0069] Figure 5 is a schematic view of a pothole 1;

[0070] Figure 6 is a schematic view of a pothole 2;

[0071] Figure 7 is a schematic view of a pothole 3;

[0072] Figure 8 is a schematic view of a pothole 4;

[0073] Figure 9 is a schematic view of a pothole 5;

[0074] Figure 10 is a schematic view of a pothole 6;

[0075] Figure 11 is a schematic view of a pothole 7;

[0076] Figure 12 is a schematic view of a pothole 8;

[0077] Figure 13 is a schematic view of a pothole 9;

[0078] Figure 14 is a schematic view of a pothole 10;

[0079] Figure 15 is a schematic view of a pothole 11; DETAILED DESCRIPTION

[0080] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present application.

[0081] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0082] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through an intermediate medium, or internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0083] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0084] A test field potholed road construction method, comprising the following steps:

[0085] Step one: typical user potholed road investigation;

[0086] Step two: potholed road parameter measurement;

[0087] Step three: potholed road parameter calculation;

[0088] Step four: potholed road surface generation;

[0089] Step five: selection of typical potholed road.

[0090] Further, the step one specifically comprises:

[0091] (1) Analysis of the causes of potholes; the formation of potholes is mainly due to two reasons, one is that the road surface material is not cohesive enough or is worn and crushed under repeated driving, resulting in the loss of fine materials and the exposure of coarse aggregates, and then the loss of loose materials forms potholes; the second is that during the construction of the road surface, the laying of some road surface facilities causes the potholes of the road surface, such as the common manhole cover road in cities;

[0092] (2) Classification according to the characteristics of potholes; the potholes are divided into manhole cover potholes and general potholes; manhole cover potholes: the geometric sizes of manhole covers in different areas are relatively uniform, but the depth and density of manhole cover potholes are greatly different due to the influence of objective factors during road repair, and the distribution of manhole covers is random; general potholes: there are many types of geometric sizes, and the distribution is random;

[0093] (3) Selecting typical road sections in typical areas; according to fault feedback, user usage condition investigation, and relevant information query on the Internet, roads with more and dense manhole covers are mostly urban roads; general potholes appear on asphalt roads, cement roads, and sandy roads, but they appear more frequently on unhardened sandy roads; the general potholes of provincial and county roads in western China are more; therefore, the investigation area of manhole cover roads is selected in cities, and the key area of general potholes is selected in western China; finally, a certain road section of Jinye Avenue in Changchun City is selected as a typical road section of manhole cover roads, and some potholes of the 318 National Highway are selected as typical road sections of general potholes.

[0094] Further, the specific steps of step two are:

[0095] 2.1 Select the parameters of the potholes to be measured and describe the potholes with the parameters, the parameters being the diameter, depth, and density of the potholes;

[0096] 2.2 Select the measuring tools and methods, measure the geometric sizes of the potholes with a height gauge and a tape measure, wherein the height gauge is mainly used to measure the depth and radius of the potholes, and the tape measure is used to measure the length and width of the road surface;

[0097] 2.3 Measure and determine the parameter values in the field;

[0098] Further, the parameters are as follows:

[0099] 1) The depth and diameter of the manhole cover: the depth is 0.015m, 0.01m, 0.02m, 0.022m, 0.018m, 0.024m, 0.025m, 0.027m, and 0.030m, a total of 9 sizes; the diameter is 0.74m;

[0100] 2) the depth and diameter of the general pothole road: the depth is 0.08m, 0.12m, 0.13m, 0.15m, 0.18m, 0.2m, 0.24m, a total of 7 sizes; the diameter is 0.2m, 0.3m, 0.4m, 0.5mm, a total of 3 sizes;

[0101] 3) the density of the well cover is 0.5 / ㎡;

[0102] 4) the density of the general pothole road: 1.2 / ㎡, 1.4 / ㎡, 1.8 / ㎡, 2 / ㎡, 2.5 / ㎡, 2.9 / ㎡, 3.3 / ㎡, 3.5 / ㎡, a total of 8 densities.

[0103] Further, the specific steps of step three are:

[0104] 3.1 the depth of the well cover is graded, and the average value of each grade is taken as the typical depth;

[0105] 3.2 the diameter of the well cover is not graded and the value is determined;

[0106] 3.3 the depth of the general pothole road is graded, and the average value of each grade is taken as the typical depth;

[0107] 3.4 the diameter size of the general pothole road is determined;

[0108] 3.5 the general pothole density is graded, and the average value of each grade is selected;

[0109] 3.6 according to the size information obtained from steps 3.1-3.5, the size of the pothole road is determined.

[0110] Further, the well cover depth is divided into 4 grades: 0.01m-0.015m, 0.015m-0.02m, 0.02m-0.025m, 0.025m-0.03m; the average value of each grade is 0.0125m, 0.0175m, 0.0225m, 0.0275m respectively;

[0111] The diameter of the well cover is 0.74m;

[0112] The depth of the general pothole road is divided into 4 grades: 0.08m-0.12m, 0.12m-0.16m, 0.16m-0.2m, 0.2m-0.24m; the average value of each grade is 0.1m, 0.14m, 0.18m, 0.22m respectively;

[0113] The diameter of the general pothole road is divided into 0.2m, 0.35m, 0.5mm, a total of 3 sizes;

[0114] The general pit density is divided into three levels, 1.2 / ㎡-2 / ㎡, 2 / ㎡-2.8 / ㎡, 2.8 / ㎡-3.6 / ㎡, and the average of each level is 1.6 / ㎡, 2.4 / ㎡, 3.2 / ㎡ respectively;

[0115] Please refer to Figures 1 to 4 The final determination of the size of the manhole cover pit includes:

[0116] Manhole cover 1: diameter 0.74m, depth 0.0125m; Manhole cover 2: diameter 0.74m, depth 0.0175m; Manhole cover 3: diameter 0.74m, depth 0.0225m; Manhole cover 4: diameter 0.74m, depth 0.0275m;

[0117] Please refer to Figures 5 to 15 The final determination of the size of the general pit includes:

[0118] Pit 1: diameter 0.2m, depth 0.1m; Pit 2: diameter 0.3m, depth 0.1m; Pit 3: diameter 0.3m, depth 0.14m; Pit 4: diameter 0.4m, depth 0.1m; Pit 5: diameter 0.4m, depth 0.14m; Pit 6: diameter 0.4m, depth 0.18m; Pit 7: diameter 0.4m, depth 0.22m; Pit 8: diameter 0.5m, depth 0.1m; Pit 9: diameter 0.5m, depth 0.14m; Pit 10: diameter 0.5m, depth 0.18m; Pit 11: diameter 0.5m, depth 0.22m.

[0119] Further, the fourth step specifically includes:

[0120] 4.1 According to the characteristics of user working conditions, at least two roads are designed in the test field, and the two roads respectively simulate the manhole cover pit road working condition and the general pit road working condition.

[0121] 4.2 According to the road surface design of the test field, the length, width of the manhole cover road and the length, width of the general pit road are determined; 4.3 The density of the manhole cover road and the density of the general pit road are respectively set;

[0122] 4.4 The number of pits of the manhole cover road and the number of pits of the general pit road are respectively calculated;

[0123] 4.5 At least three specifications of pits are set on the general pit road;

[0124] 4.6 The number of each kind of pit on the general pit road is calculated;

[0125] 4.7 The pits on the general pit road are arranged according to the principle of non-intersection and random distribution, each distribution is called a combination, and the road surface requires to generate 100 different combinations.

[0126] Further, four roads are designed in the test field, which are 1# pothole road, 2# pothole road, 3# pothole road and 4# pothole road respectively; wherein 1# pothole road simulates the working condition of pothole road with manhole cover, and the rest pothole roads simulate the general pothole road working condition;

[0127] The length of 1# pothole road is 50m, and the width is 4m; the length of 2# pothole road is 100m, and the width is 4m; the length of 3# pothole road is 100m, and the width is 4m; the length of 4# pothole road is 100m, and the width is 4m;

[0128] The density of 1# pothole road is set to 0.5 / ㎡; the density of 2# pothole road is set to 1.6 / ㎡; the density of 3# pothole road is set to 2.4 / ㎡; the density of 4# pothole road is set to 3.2 / ㎡;

[0129] The total number of 1# pothole road is 200m2×0.5 / ㎡=100 potholes; the total number of 2# pothole road is 400m2×1.6 / ㎡=640 potholes; the total number of 3# pothole road is 400m2×2.4 / ㎡=960 potholes; the total number of 4# pothole road is 400m2×3.2 / ㎡=1280 potholes;

[0130] The 2# pothole road is set to have pothole 6, pothole 8 and pothole 11, a total of 3 kinds of potholes; the 3# pothole road is set to contain pothole 2, pothole 4 and pothole 7, a total of 3 kinds of potholes; the 4# pothole road is set to contain pothole 1, pothole 3, pothole 5 and pothole 10, a total of 4 kinds of potholes;

[0131] The average number of each kind of pothole in 2# pothole road is 640 / 3=213; the average number of each kind of pothole in 3# pothole road is 960 / 3=320; the average number of each kind of pothole in 4# pothole road is 1280 / 4=320;

[0132] 2#, 3# and 4# pothole roads are arranged according to the principle of non-intersection and random distribution, each distribution of which is called a combination, and 100 different combinations are required for each road surface.

[0133] Further, the non-intersection judgment condition is that the distance between the centers is greater than the sum of the two radii.

[0134] Further, the specific content of step five is:

[0135] 5.1 According to the obtained multi-body dynamics model parameters of the whole vehicle, a whole vehicle dynamics model of the test vehicle is established in ADAMS / CAR;

[0136] 5.2 A digital road surface model of 100 pothole roads is established in ADAMS / CAR;

[0137] 5.3 According to the established whole vehicle multi-body dynamics model and the digital test road model, the virtual test field analysis of the suspension system whole vehicle durability test is carried out, the whole vehicle model is carried out on the constructed digital road for virtual test, and the wheel Z direction force is obtained;

[0138] 5.4 The rain flow counting method and the Miner criterion are used for damage calculation of the wheel Z direction force, and the damage of 100 kinds of pit road Z direction forces is obtained;

[0139] 5.5 The obtained damage is arranged in order from small to large, the damage value ranked the 95th is obtained, and is recorded as the 95% percentile damage value;

[0140] 5.6 The road surface representing the 95% percentile damage value is selected as the final pit road.

[0141] Obviously, the above embodiments are only examples for clearly illustrating, but not limitation to the embodiments. For ordinary skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, all the embodiments are not required to be exhausted, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A method of constructing a test track uneven road surface, characterized by, It comprises the following steps: Step one: typical user pothole road investigation, specifically including:

101. Analysis of the causes of pothole road; 102. According to the characteristics of pothole road classification, the pothole road is divided into manhole cover pothole road and general pothole road; 103. Select typical road section in typical area; Step two: pothole road parameter measurement, the specific steps are:

201. Select the parameter pit of the measured pothole road and describe the pothole road with parameters, the parameters are the diameter, depth and density of the pothole; 202. Select the measuring tool and measuring method, measure the geometric size of the pothole by height ruler and tape measure, the height ruler is used to measure the depth and radius of the pothole, and the tape measure is used to measure the length and width of the road surface; 203. Measure and determine the parameter value on site; Step three: pothole road parameter calculation, the specific steps are:

301. Grade the depth of manhole cover, and take the average value of each grade as the typical depth; 302. The diameter of the manhole cover is not graded and the value is determined; 303. Grade the depth of the general pothole road, and take the average value of each grade as the typical depth; 304. Determine the diameter size of the general pothole road; 305. Grade the general pothole density and select the average value of each grade; 306. Determine the size of the pothole road according to the size information obtained in steps 301-305; The manhole cover depth is divided into four grades: 0.01m-0.015m, 0.015m-0.02m, 0.02m-0.025m, 0.025m-0.03m; the average value of each grade is 0.0125m, 0.0175m, 0.0225m, 0.0275m respectively; The diameter of the manhole cover is 0.74m; The depth of the general pothole road is divided into four grades: 0.08m-0.12m, 0.12m-0.16m, 0.16m-0.2m, 0.2m-0.24m; the average value of each grade is 0.1m, 0.14m, 0.18m, 0.22m respectively; The diameter of the general pothole road is divided into 0.2m, 0.35m, 0.5m, a total of three sizes; The general pothole density is divided into three grades, which are 1.2 / ㎡-2 / ㎡, 2 / ㎡-2.8 / ㎡, 2.8 / ㎡-3.6 / ㎡ respectively, and the average value of each grade is 1.6 / ㎡, 2.4 / ㎡, 3.2 / ㎡ respectively; The final determination of the size of the manhole cover pothole road includes: Manhole cover 1: diameter 0.74m, depth 0.0125m; Manhole cover 2: diameter 0.74m, depth 0.0175m; Manhole cover 3: diameter 0.74m, depth 0.0225m; Manhole cover 4: diameter 0.74m, depth 0.0275m; The final determination of the general pothole size includes: Pit 1: diameter 0.2m, depth 0.1m; pit 2: diameter 0.3m, depth 0.1m; pit 3: diameter 0.3m, depth 0.14m; pit 4: diameter 0.4m, depth 0.1m; pit 5: diameter 0.4m, depth 0.14m; pit 6: diameter 0.4m, depth 0.18m; pit 7: diameter 0.4m, depth 0.22m; pit 8: diameter 0.5m, depth 0.1m; pit 9: diameter 0.5m, depth 0.14m; Pit 10: diameter 0.5m, depth 0.18m; pit 11: diameter 0.5m, depth 0.22m; Step four: pit road generation; the specific content of the step four is:

401. According to the characteristics of user working conditions, at least two roads are designed on the test field, and the two roads respectively simulate the manhole cover pit road working condition and the general pit road working condition; 402. According to the test field road design, the length and width of the manhole cover road and the length and width of the general pit road are determined; 403. The density of the manhole cover road and the density of the general pit road are set respectively; 404. The number of pits of the manhole cover road and the number of pits of the general pit road are calculated respectively; 405. At least three specifications of pits are set on the general pit road; 406. The number of each kind of pit on the general pit road is calculated; 407. The pits on the general pit road are arranged according to the principle of non-intersection and random distribution, and each distribution is called a combination, and 100 different combinations of road surface are required to be generated; Step five: selection of typical pit road; the specific content of the step five is:

501. According to the obtained multi-body dynamics model parameters of the whole vehicle, the whole vehicle dynamics model of the test vehicle is established in ADAMS / CAR; 502. 100 kinds of digital road surface models of pit road are established in ADAMS / CAR; 503. According to the established whole vehicle multi-body dynamics model and digital test road surface model, the virtual test field analysis of the suspension system whole vehicle durability test is carried out, the whole vehicle model is carried out on the constructed digital road surface, and the wheel Z direction force is obtained; 504. The rain flow counting method and the Miner criterion are used to calculate the damage of the wheel Z direction force, and the damage of the wheel Z direction force of 100 kinds of pit roads is obtained; 505. The obtained damage is arranged in order from small to large, and the damage value ranked the 95th is obtained, which is recorded as the 95% quantile damage value; 506. The road surface representing the 95% quantile damage value is selected as the final pit road.

2. The method of claim 1, wherein, The pit road parameters are as follows: 1) The depth and diameter of the manhole cover: the depth is 0.015m, 0.01m, 0.02m, 0.022m, 0.018m, 0.024m, 0.025m, 0.027m and 0.030m, a total of 9 sizes; the diameter is 0.74m; 2) The depth and diameter of the general pit road: the depth is 0.08m, 0.12m, 0.13m, 0.15m, 0.18m, 0.2m and 0.24m, a total of 7 sizes; the diameter is 0.2m, 0.3m, 0.4m and 0.5m, a total of 4 sizes; 3) The density of the manhole cover is 0.5 per square meter; 4) general pothole density: 1.2 / ㎡, 1.4 / ㎡, 1.8 / ㎡, 2 / ㎡, 2.5 / ㎡, 2.9 / ㎡, 3.3 / ㎡, 3.5 / ㎡, a total of 8 densities.

3. The method of claim 1, wherein, A total of 4 roads are designed in the test field, which are 1# pothole road, 2# pothole road, 3# pothole road, and 4# pothole road. Among them 1# pothole road simulates the working condition of manhole cover pothole road, and the rest of the pothole road simulates the general pothole road working condition. The 1# pothole road is 50m long and 4m wide; the 2# pothole road is 100m long and 4m wide; the 3# pothole road is 100m long and 4m wide; and the 4# pothole road is 100m long and 4m wide. The 1# pothole road density is set to 0.5 / ㎡; the 2# pothole road density is set to 1.6 / ㎡; the 3# pothole road density is set to 2.4 / ㎡; and the 4# pothole road density is set to 3.2 / ㎡; The 1# pothole road has a total of 200㎡×0.5 / ㎡=100 potholes; the 2# pothole road has a total of 400㎡×1.6 / ㎡=640 potholes; the 3# pothole road has a total of 400㎡×2.4 / ㎡=960 potholes; and the 4# pothole road has a total of 400㎡×3.2 / ㎡=1280 potholes; The 2# pothole road is set to have pothole 6, pothole 8, and pothole 11, a total of 3 kinds of potholes; the 3# pothole road contains pothole 2, pothole 4, and pothole 7, a total of 3 kinds of potholes; and the 4# pothole road contains pothole 1, pothole 3, pothole 5, and pothole 10, a total of 4 kinds of potholes; The average number of each kind of pothole in the 2# pothole road is 640 / 3=213; the average number of each kind of pothole in the 3# pothole road is 960 / 3=320; and the average number of each kind of pothole in the 4# pothole road is 1280 / 4=320; 2#, 3#, and 4# pothole roads are arranged according to the principle of non-intersection and random distribution. Each distribution is called a combination, and 100 different combinations are required for each road surface.

4. The method of claim 3, wherein, The non-intersection judgment condition is that the distance between the centers is greater than the sum of the two radii.

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