Vehicle allocation design method for ship lightering vehicle

Abstract

The invention provides a vehicle allocation design method for a ship lightering vehicle. The vehicle allocation design method comprises the steps that S1, vehicle pre-allocation is conducted according to lightering cargo information; s2, the actual bearing rate of the lightering vehicle is determined, and the minimum value n of the number of axes of the lightering vehicle is determined according to the actual bearing rate; s3, the traction force and the running resistance of the lightering vehicle are obtained, and the traction force should be larger than the running resistance; s4, obtaining the pressure of the lightering vehicle on the ground, wherein the pressure of the lightering vehicle on the ground is smaller than the bearing capacity of the site; s5, the front supporting point axial pressure and the rear supporting point axial pressure of the lightering vehicle are obtained, and it is determined that the front supporting point axial pressure and the rear supporting point axial pressure meet the lightering requirement; and S6, determining that the stability of the lighted goods in the lightering process meets the requirement. According to the method, stability analysis can be carried out on lighted goods in the lightering process, and specific optimization measures are provided for vehicle distribution on the premise that the stability is met, so that vehicle distribution is more accurate, and the overturning danger is reduced.

Description

Technical Field

[0001] This application relates to the technical field of shipbuilding, and more specifically, to a vehicle allocation design method for a ship barge carrier. Background Art

[0002] In recent years, with the development of technology, there are more and more large-scale construction equipment in China, and the demand for heavy cargo barge transportation operations in various industries has also been increasing. Especially in the shipbuilding industry, most of them are large steel structures, with increasing scale and size.

[0003] Self-Propelled Modular Transporter (SPMT for short) has excellent characteristics such as flexible use, convenient loading and unloading, and large load capacity. Therefore, it has been increasingly widely used in the process of loading a ship from the manufacturing site to the ro-ro ship by barge. Through the use of the above-mentioned barge carrier, off-site construction of ship sections can be realized, thereby saving the cost of shipyards and improving shipbuilding efficiency.

[0004] However, when the barge cargo is a heavy piece, the height-to-length ratio of the barge cargo is small, so there is a large risk of center of gravity deviation and overturning, which will cause phenomena such as deformation of the vehicle deck frame of the barge carrier, damage to the hydraulic suspension and hydraulic support.

[0005] In summary, an improved technical solution is needed to address the deficiencies of the above-mentioned existing technologies. Summary of the Invention

[0006] The purpose of the embodiments of this application is to provide a vehicle allocation design method for a ship barge carrier, which can analyze the stability of the barge cargo during the barge transportation process, and provide specific optimization measures for vehicle allocation on the premise of meeting stability, so as to make the vehicle allocation more accurate and reduce the risk of overturning.

[0007] This application provides a vehicle allocation design method for a ship barge carrier, including the following steps:

[0008] S1. Obtain the barge cargo information of the ship, and perform preliminary vehicle allocation according to the barge cargo information;

[0009] S2. Determine the actual load factor of the barge carrier based on the preliminary vehicle allocation, determine the minimum value n of the number of axles of the barge carrier according to the actual load factor, compare the number of axles in the preliminary vehicle allocation with the minimum value n of the number of axles, and the number of axles in the preliminary vehicle allocation should be greater than or equal to the minimum value n of the number of axles;

[0010] S3. Obtain the traction force and driving resistance of the barge carrier, and compare the traction force and the driving resistance. The traction force should be greater than the driving resistance;

[0011] S4. Obtain the pressure of the barge carrier on the ground, and the pressure of the barge carrier on the ground should be less than the bearing capacity of the site;

[0012] S5. Establish a calculation coordinate system with the lower front endpoint of the power module unit of the barge carrier as the origin, obtain the axial pressure of the front support point and the axial pressure of the rear support point of the barge carrier, and determine that the axial pressure of the front support point and the axial pressure of the rear support point meet the barge requirements;

[0013] S6. Determine that the stability of the barge cargo during the barge process meets the requirements.

[0014] In an implementable manner, the barge cargo information at least includes: the center of gravity position of the barge cargo and the weight of the barge cargo.

[0015] In an implementable manner, the actual load factor should be less than or equal to 80% of the rated axle load.

[0016] In an implementable manner, in step S3, when the traction force is less than or equal to the running resistance, the barge carrier needs to be optimized.

[0017] In an implementable manner, in step S4, the pressure of the barge carrier on the ground should be less than 10 t / m 2 .

[0018] In an implementable manner, when the pressure of the barge carrier on the ground should be greater than or equal to 10 t / m 2 , then the barge carrier needs to be optimized.

[0019] In an implementable manner, the optimization measures at least include: increasing the number of axles of the barge carrier or increasing the number of power module units.

[0020] In an implementable manner, in step S6, determining the stability of the barge cargo includes the following:

[0021] S61. Obtain the tipping moment and the anti-tipping moment respectively, and compare the tipping moment and the anti-tipping moment. The tipping moment should be less than or equal to the anti-tipping moment;

[0022] S62. Calculate the anti-tipping safety factor, and the anti-tipping safety factor should be greater than a predetermined value.

[0023] In an implementable manner, when the tipping moment is greater than the anti-tipping moment, weld and strengthen the barge cargo and the barge bracket, or set counterweight iron at the bottom of the barge cargo.

[0024] Compared with the prior art, the beneficial effects of this application are:

[0025] In the technical solution of the present application, it is possible to perform a stability analysis on the barge cargo during the barge process. On the premise of meeting the stability, specific optimization measures are provided for vehicle allocation to make the vehicle allocation more accurate and reduce the tipping risk. Moreover, in the optimization measures provided by the present application, the weld length and fillet size of the barge cargo and the bracket can also be determined by calculating the resultant external force in different directions to offset the instability caused by the external force. Counterweight iron can also be set on the bracket to lower the center of gravity of the barge cargo, reduce the left and right deviation of the barge vehicle, and the adverse effects such as the left and right and up and down movement of the center of gravity of the barge cargo, and ensure the barge safety to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a flowchart of the vehicle allocation design method for the ship barge vehicle according to an embodiment of the present invention.

[0027] Figure 2 is a top view of the barge vehicle and the barge cargo in the vehicle allocation design method for the ship barge vehicle according to an embodiment of the present invention.

[0028] Figure 3 is a front view of the barge vehicle and the barge cargo in the vehicle allocation design method for the ship barge vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following further describes in detail the specific embodiments of the present invention with reference to the accompanying drawings. These embodiments are only for illustrating the present invention and are not intended to limit the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, in the description of the present invention, unless otherwise specified, "a plurality of" means two or more than two.

[0033] See Figures 1 to 3 , this application provides a vehicle allocation design method for a ship barge, including the following steps:

[0034] S1. Obtain the barge cargo information of the ship, and perform pre-vehicle allocation according to the barge cargo information.

[0035] It should be noted that the barge cargo is a ship's heavy lift. The barge cargo information includes at least: the self-type steel structure information, dimensions, and distribution positions of other outfitting parts of the barge cargo, so as to determine the center of gravity position and weight of the barge cargo.

[0036] In step S1, when determining the center of gravity position of the barge cargo, it is determined according to the original coordinates of the ship.

[0037] S2. Based on the pre-vehicle allocation, determine the actual load-bearing rate of the barge vehicle. According to the actual load-bearing rate, determine the minimum value n of the number of axles of the barge vehicle, and compare the number of axles in the pre-vehicle allocation with the minimum value n of the number of axles. The number of axles in the pre-vehicle allocation should be greater than or equal to the minimum value n of the number of axles.

[0038] In an implementable manner, the actual load-bearing rate should be less than or equal to 80% of the rated axle load to ensure the safety of the barge vehicle during the barge process.

[0039] In an implementable manner, the calculation process of the actual load-bearing rate is as follows:

[0040] β=(G 0 +G 1 +G 2 ) / np≤80% (1)

[0041] G 0 =G(1 + μ)+G 托架 (2)

[0042] In the formula:

[0043] β is the actual load-bearing rate of the modular vehicle;

[0044] G is the weight of the barge cargo;

[0045] G 托架 is the weight of the bracket;

[0046] G 0 is the sum of the calculated weight of the barge cargo and the weight of the bracket;

[0047] G 1 is the axle weight of the barge vehicle;

[0048] G2 is the weight of the Paralleling and Protection Unit (PPU);

[0049] n is the minimum value of the number of axles;

[0050] μ is the deviation coefficient of the weight of the transported goods;

[0051] p is the axle load mass of the module vehicle.

[0052] S3. Obtain the traction force and driving resistance of the barge carrier, and compare the traction force with the driving resistance. When the traction force is greater than the driving resistance, the barge transportation requirement is met, and the barge carrier will not slip during the barge transportation process.

[0053] In an implementable manner, the calculation processes of the traction force and the driving resistance are as follows:

[0054] F = F 0 ×n 0 (3)

[0055] P = (G 0 +G 1 +G 2 ) × (f + i y ) (4)

[0056] In the formula:

[0057] F is the traction force of the barge carrier;

[0058] F 0 is the rated traction force of the drive axle of the barge carrier;

[0059] n 0 is the number of drive axles of the barge carrier;

[0060] P is the driving resistance of the barge carrier;

[0061] f is the rolling friction of the barge carrier;

[0062] i y is the slope in the Y direction.

[0063] It should be noted that according to the usage requirements of the SMPT barge carrier, after the barge transportation road surface is leveled, the longitudinal and transverse slopes are not greater than 2%, that is, the slope angle α is less than 1.145°.

[0064] In an implementable manner, in step S3, when the traction force is less than or equal to the driving resistance, the barge carrier needs to be optimized. The optimization measures at least include: increasing the number of axles of the barge carrier, or increasing the number of Paralleling and Protection Units (PPU).

[0065] S4. Obtain the pressure of the barge carrier on the ground and determine whether the pressure of the barge carrier on the ground is less than the bearing capacity of the site. When the pressure of the barge carrier on the ground is less than the bearing capacity of the site, the barge transportation requirement is met.

[0066] In an implementable manner, the calculation process of the pressure of the barge carrier on the ground is as follows:

[0067] P = G 0 + G 1 + G 2 / S (5)

[0068] In the formula:

[0069] P is the pressure of the modular vehicle group of the barge carrier on the ground;

[0070] S is the ballast area;

[0071] G 0 is the sum of the calculated weight of the barge cargo and the weight of the bracket;

[0072] G 1 is the axle weight of the barge carrier;

[0073] G 2 is the weight of the PPU.

[0074] In an implementable manner, in step S4, the pressure of the barge carrier on the ground should be less than 10 t / m 2 . When the pressure of the barge carrier on the ground should be greater than or equal to 10 t / m 2 , it is necessary to optimize the barge carrier vehicle, and the optimization measures include at least: increasing the number of axles of the barge carrier or increasing the number of power module units.

[0075] S5. Establish a calculation coordinate system with the lower front endpoint of the power module unit as the origin, as Figure 3 shown. Configure the vehicle according to four-point support, calculate the axle pressure of the front support point and the axle pressure of the rear support point of the barge carrier, and determine that both the axle pressure of the front support point and the axle pressure of the rear support point are less than 80% of the rated axle load of the barge carrier.

[0076] In an implementable manner, the axle pressure calculation uses the vertical force balance equation and the moment balance equation as control equations. Then the force balance equation is:

[0077]

[0078] In the formula:

[0079] P 1 is the axle pressure of the front support point;

[0080] P 2Axial compression at the rear support point;

[0081] m 1 Is the number of axis lines of the front support group;

[0082] n 1 Is the number of axis lines of the rear support group;

[0083] N 1 Is the axle weight of the modular vehicle;

[0084] N 2 Is the weight of the load-bearing wood of the modular vehicle;

[0085] G i Is the axle weight;

[0086] G i "Is the weight of the load-bearing wood;

[0087] L is the horizontal distance from the center of gravity of the barge item to the origin of the calculation coordinate system;

[0088] L i Is the horizontal distance from each axle to the origin of the calculation coordinate system;

[0089] L i ’Is the horizontal distance from the center of gravity of each module group to the origin of the calculation coordinate system;

[0090] L i "Is the horizontal distance from each load-bearing wood to the origin of the calculation coordinate system.

[0091] It should be noted that, as Figure 3 shown, in this embodiment, a total of 6 groups of module groups are set, and the number of axis lines in each group of module groups is 6. When confirming the horizontal distance L i ’ from the center of gravity of each module group to the origin of the calculation coordinate system, the horizontal distance from the center of gravity of the PPU to the origin of the calculation coordinate system also needs to be considered.

[0092] It also needs to be noted that assuming the ground is basically flat, the component of the pressure along the ground direction is ignored, and only the vertical component is considered.

[0093] In an implementable manner, when the axial compression at the front support point and the axial compression at the rear support point are both greater than or equal to 80% of the rated axle load of the barge vehicle, the barge vehicle allocation needs to be optimized. The optimization measures at least include: increasing the number of axis lines of the barge vehicle, or increasing the number of power module units.

[0094] S6. Based on the barge cargo information and the optimized vehicle allocation plan, determine that the stability of the barge cargo during the barge process meets the requirements.

[0095] In an implementable manner, step S6 at least includes the following content:

[0096] S61. Obtain the overturning moment and the anti-overturning moment respectively, and compare the overturning moment with the anti-overturning moment. When the overturning moment is less than or equal to the anti-overturning moment, the stability requirement is met.

[0097] The theoretical calculation formula for the overturning moment is as follows:

[0098] M 0x = F x × H 1 (8)

[0099] M 0y = F y × H 1 (9)

[0100] In the formula:

[0101] M 0x is the overturning moment in the X direction, with the unit of t·m;

[0102] M 0y is the overturning moment in the Y direction, with the unit of t·m;

[0103] F x is the resultant external force in the X direction;

[0104] F y is the resultant external force in the Y direction;

[0105] H 1 is the center of gravity height of the barge cargo, with the unit of m.

[0106] The theoretical calculation formula for the anti-overturning moment is as follows:

[0107] M 1x = G’ 0 × L x (10)

[0108] M 1y = G’ 0 × L y (11)

[0109] In the formula:

[0110] M 1x is the anti-overturning moment in the X direction, with the unit of t·m;

[0111] M 1y is the anti-overturning moment in the Y direction, with the unit of t·m;

[0112] G’ 0 is the calculated weight of the barge cargo;

[0113] L x is the anti-overturning force arm in the X direction during barge transportation, with the unit of m;

[0114] L y It is the anti-overturning moment arm in the Y direction during barge transportation, with the unit of m.

[0115] In an implementable manner, when the overturning moment is greater than the anti-overturning moment, the barge cargo and the barge bracket are welded and strengthened, or counterweight iron is set at the bottom of the barge cargo to reduce the center of gravity height of the barge cargo and improve the safety of barge transportation.

[0116] In an implementable manner, when welding and strengthening the barge cargo and the bracket of the barge vehicle to resist the influence of the above instability factors, the following contents are included:

[0117] There are various potential factors during the barge transportation process of the barge vehicle that affect the safety of barge transportation. First, air flow will generate pressure on the barge cargo; when the barge vehicle brakes, the center of gravity position of the barge cargo will change due to inertia; during the barge transportation process of the barge cargo, it will also be affected by the vibrations of multiple components of the barge vehicle itself; factors such as uneven roads with slopes and centrifugal force generated when the vehicle group turns will all affect the barge transportation. If the design of the number of axles is only based on the weight of the barge cargo, there will be many potential safety hazards, which is not conducive to the improvement and development of barge transportation technology.

[0118] In the prior art, calculating the load on the front and rear support axles based on the center points of the front and rear supports to the center of gravity position of the barge cargo ignores the self-weight of the axles of the barge vehicle, the self-weight of the PPU, and the weight of the bearing wood above the vehicle deck, resulting in a certain error in the accuracy of the calculated axle load. When barge transporting high-center-of-gravity barge cargo, external factors such as wind load and braking force are often ignored. Therefore, the previous barge transportation methods can no longer ensure safety and may cause serious consequences such as overturning.

[0119] In this embodiment, the traveling direction of the barge vehicle is defined as the X direction, and the direction perpendicular to the X direction on the horizontal plane is the Y direction; the resultant external force during the barge transportation process of the barge vehicle includes the resultant external force in the X direction and the resultant external force in the Y direction. During the barge transportation process, the barge cargo will be affected by wind load F 1 , dynamic load F 2 , braking force F 3 , ramp force F 4 , centrifugal force F 5 etc. Therefore, the calculation processes of the resultant external force in the X direction and the resultant external force in the Y direction are as follows:

[0120] F x = F 1x + F 2x + F 3x + F 4x (12)

[0121] F y = F 1y + F2y +F 3y +F 4y +F 5 (13)

[0122] In the formula:

[0123] F x is the resultant external force in the X direction;

[0124] F 1x is the wind load in the X direction;

[0125] F 2x is the dynamic load in the X direction;

[0126] F 3x is the braking force in the X direction;

[0127] F 4x is the ramp force in the X direction;

[0128] F y is the resultant external force in the Y direction;

[0129] F 1Y is the wind load in the Y direction;

[0130] F 2Y is the dynamic load in the Y direction;

[0131] F 3Y is the braking force in the Y direction;

[0132] F 4Y is the ramp force in the Y direction;

[0133] F 5 is the centrifugal force in the Y direction.

[0134] The weld length required for welding the barge cargo is determined by the resultant external force in the X direction and the resultant external force in the Y direction as follows:

[0135]

[0136] In the formula:

[0137] l x is the total weld length in the X direction;

[0138] l y is the total weld length in the Y direction;

[0139] g is the acceleration due to gravity, with the unit of N / kg;

[0140] K is the leg size;

[0141] [σ] is the allowable stress.

[0142] In another implementable manner, counterweight iron blocks are arranged at the bottom of the lighterage cargo to reduce the height of the center of gravity of the lighterage cargo and improve the safety of lighterage.

[0143] The calculation process of the center of gravity height H after arranging the counterweight iron blocks is as follows:

[0144] H = [((G × H'+ G 托架 × L) / (G + G 托架 + G 压铁 ))] (16)

[0145] In the formula:

[0146] H' is the original center of gravity height of the lighterage cargo;

[0147] L is the distance from the center of gravity of the bracket to the origin of the calculation coordinate;

[0148] G 压铁 is the weight of the iron block.

[0149] S62. Calculate the anti-overturning safety factor, and determine that the stability requirement is met when the anti-overturning safety factor is greater than the predetermined value.

[0150] It should be noted that: since the overturning situation in the X direction is better than that in the Y direction, therefore, in this embodiment, the anti-overturning safety factor is calculated based on the anti-overturning moment L y in the Y direction. The calculation process of the anti-overturning safety factor is as follows:

[0151]

[0152] In the formula:

[0153] K y is the anti-overturning safety factor in the Y direction;

[0154] H is the center of gravity height H after arranging the counterweight iron blocks;

[0155] G is the weight of the lighterage cargo;

[0156] L y is the anti-overturning force arm in the Y direction during lighterage;

[0157] F y is the resultant external force in the Y direction.

[0158] In an implementable manner, when the anti-overturning safety factor is greater than 1.35, the lighterage cargo meets the stability requirement for direct lighterage. When the anti-overturning safety factor is less than or equal to 1.35, return to step S61 to re-arrange the counterweight iron blocks or re-determine the length of the welded seam until the anti-overturning safety factor is greater than 1.35.

[0159] In summary, the vehicle allocation design method for a ship barge provided by the present application can perform a stability analysis on the barge cargo during the barge operation. On the premise of meeting the stability requirements, specific optimization measures are provided for vehicle allocation to make the vehicle allocation more accurate and reduce the tipping risk. Moreover, in the optimization measures provided by the present application, the weld length and weld leg size between the barge cargo and the bracket can be determined by calculating the resultant external force in different directions to offset the instability caused by the external force. Counterweights can also be set on the bracket to lower the center of gravity of the barge cargo, reduce adverse effects such as the left-right deviation of the barge vehicle, and the left-right and up-down movement of the center of gravity of the barge cargo, and ensure the barge safety to the greatest extent.

[0160] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the technical principle of the present invention, several improvements and substitutions can be made, and these improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A method for designing a ship lighter vehicle, characterized in that: The following steps are involved: S1. Obtain the lightering cargo information of the ship and pre-allocate the vehicle according to the lightering cargo information; S2. Determine the actual load rate of the lighter truck based on the pre-allocated truck, determine the minimum value n of the number of axles of the lighter truck according to the actual load rate, compare the number of axles in the pre-allocated truck with the minimum value n of the number of axles, and the number of axles in the pre-allocated truck should be greater than or equal to the minimum value n of the number of axles; S3, obtaining the traction force and driving resistance of the lighter truck, and comparing the traction force and the driving resistance. The traction force should be greater than the driving resistance; S4. Obtain the pressure of the lighter truck on the ground. The pressure of the lighter truck on the ground should be less than the bearing capacity of the site; S5. Establish a calculation coordinate system with the front lower end point of the power module unit of the lighter as the origin, obtain the front support point axial pressure and the rear support point axial pressure of the lighter, and determine whether the front support point axial pressure and the rear support point axial pressure meet the lightering requirements; S6. Ensure that the stability of the cargo during the transfer process meets the requirements.

2. The method for designing a ship lighter vehicle according to claim 1, characterized in that: The information of the lightered cargo includes at least: the center of gravity position of the lightered cargo and the weight of the lightered cargo.

3. The method for designing a ship lighter vehicle according to claim 1, characterized in that: The actual load factor should be less than or equal to 80% of the rated axle load.

4. The method for designing a ship lighter vehicle according to claim 1, characterized in that: In step S3, when the traction force is less than or equal to the driving resistance, the lighter vehicle needs to be optimized.

5. The method for designing a ship lighter vehicle according to claim 1, characterized in that: In step S4, the pressure of the lighter truck on the ground should be less than 10t / m 2 .

6. The method for designing a ship lighter vehicle according to claim 1, characterized in that: The pressure of the lighter truck on the ground should be greater than or equal to 10t / m 2 When the transport and distribution vehicles are optimized.

7. The method for designing a ship lighter vehicle according to claim 4 or 6, characterized in that: The optimization measures at least include: increasing the number of axles of the transfer vehicle, or increasing the number of power module units.

8. The method for designing a ship lighter vehicle according to claim 1, characterized in that: In step S6, determining the stability of the lightered cargo includes the following: S61, respectively obtaining the overturning moment and the anti-overturning moment, and comparing the overturning moment and the anti-overturning moment, the overturning moment should be less than or equal to the anti-overturning moment; S62. Calculate the anti-overturning safety factor, which should be greater than a predetermined value.

9. The method for designing a ship lighter vehicle according to claim 1, characterized in that: When the overturning moment is greater than the anti-overturning moment, the lighted cargo and the lighted bracket are welded and reinforced, or a counterweight is set at the bottom of the lighted cargo.

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