CN-121997832-A - Anti-rutting regulation and control method for regenerating warm mix asphalt by large-mixing amount milling material

CN121997832ACN 121997832 ACN121997832 ACN 121997832ACN-121997832-A

Abstract

The invention discloses an anti-rutting regulation and control method for regenerating warm mix asphalt by using a large amount of milling materials, which relates to the technical field of automatic control and comprises the following steps of: performing penetration test and softening point test on old asphalt in a milling material to obtain an old asphalt penetration value and an old asphalt softening point value, and performing melting point test on a warm mix to be mixed to obtain a warm mix melting point value; step two, establishing a two-dimensional rectangular calculation domain, dividing the two-dimensional rectangular calculation domain into a first calculation section, a second calculation section and a third calculation section along the horizontal direction, extracting anti-rutting performance evaluation indexes after iteration is completed, step three, comparing the anti-rutting performance evaluation indexes with a preset target threshold value, adjusting proportioning parameters according to comparison results, returning to the step two, re-simulating until target requirements are met, and determining final proportioning parameters. The invention realizes the coupling simulation of the diffusion evolution and the high-temperature viscous flow behavior of the new asphalt interface and the old asphalt interface, and can rapidly screen and optimize the proportioning scheme in the virtual environment.

Inventors

GU XIUJUAN
CHI XUEHUI
QIN PEIKAI
HAN TONGRUI
YANG HAIE

Assignees

聊城市公路事业发展中心东阿公路事业发展中心
聊城市交通发展有限公司
聊城市公路事业发展中心茌平公路事业发展中心

Dates

Publication Date: 20260508
Application Date: 20260129

Claims (10)

1. The rut resistance control method for regenerating warm mix asphalt by using a large amount of milling materials is characterized by comprising the following steps of: Performing penetration test and softening point test on old asphalt in a milling material to obtain an old asphalt penetration value and an old asphalt softening point value, performing penetration test and softening point test on new asphalt to be blended to obtain a new asphalt penetration value and a new asphalt softening point value, and performing melting point test on a warm mixing agent to be blended to obtain a melting point value of the warm mixing agent; Establishing a two-dimensional rectangular calculation domain, dividing the two-dimensional rectangular calculation domain into a first calculation section, a second calculation section and a third calculation section along the horizontal direction, wherein the first calculation section represents an old asphalt phase region, the third calculation section represents a new asphalt phase region, the second calculation section represents a new and old asphalt interface transition region, establishing phase-sequence parameter distribution represents asphalt phase state attributes, establishing lattice Boltzmann velocity discrete lattice simulation asphalt flow behaviors, performing alternating iterative calculation of a phase-field updating sub-step and a lattice Boltzmann collision migration sub-step, applying external load conditions formed by simulating ruts, and extracting anti-rut performance evaluation indexes after iteration is completed; And thirdly, comparing the anti-rutting performance evaluation index with a preset target threshold value, adjusting the proportioning parameters according to the comparison result, returning to the second step for re-simulation until the target requirement is met, and determining the final proportioning parameters.
2. The method according to claim 1, wherein the first step further comprises the steps of obtaining aggregate particle size distribution data of the milled material by adopting a laser particle size analyzer to conduct particle size distribution test on aggregate particles in the milled material, obtaining a three-dimensional space distribution image of internal pores of the milled material by adopting X-ray computer tomography equipment to scan a milled material sample, and extracting initial porosity values of the milled material and average diameter values of pores of the milled material from the three-dimensional space distribution image.
3. The method of claim 1, wherein the phase-sequence parameter in the second step is a continuous interval ranging from zero to one, wherein the phase-sequence parameter in the second step is zero, which indicates that the corresponding position is completely old asphalt phase, and wherein the phase-sequence parameter in the first step is one, which indicates that the corresponding position is completely new asphalt phase, and wherein the phase-sequence parameter in the second step is between zero and one, which indicates that the corresponding position is in a mixed transition state of new and old asphalt, wherein the phase-sequence parameter in the first step is initialized, wherein the phase-sequence parameter in the first step is set to zero, wherein the phase-sequence parameter in the third step is set to one, and wherein the phase-sequence parameter in the second step is set to a transition profile linearly tapered from zero to one in the horizontal direction.
4. The method according to claim 1, wherein the lattice boltzmann velocity discrete lattice in the second step is velocity-space-discrete using a D2Q9 lattice structure, the D2Q9 lattice structure is provided with nine discrete velocity directions at each lattice point, the nine discrete velocity directions including one zero velocity direction, four unit velocity directions along positive and negative directions of the coordinate axis, and four unit velocity directions along diagonal directions, nine particle distribution functions are defined at each lattice point, the nine particle distribution functions respectively correspond to the nine discrete velocity directions, and each particle distribution function characterizes the number density of virtual particles moving along the corresponding discrete velocity direction.
5. The method of claim 1, wherein the step two further comprises setting a simulated temperature value, wherein the simulated temperature value is higher than an old asphalt softening point value, higher than a new asphalt softening point value and higher than a temperature mixer melting point value, establishing a correlation rule between a phase-sequence parameter and lattice Boltzmann local viscosity, determining an old asphalt reference viscosity value according to the old asphalt penetration value and the old asphalt softening point value, determining a new asphalt reference viscosity value according to the new asphalt penetration value and the new asphalt softening point value, performing temperature correction on the old asphalt reference viscosity value and the new asphalt reference viscosity value according to the simulated temperature value to obtain a temperature-corrected old asphalt viscosity value and a temperature-corrected new asphalt viscosity value, setting the local kinematic viscosity at the current lattice point to be the temperature-corrected old asphalt viscosity value when the current phase-sequence parameter value at the current lattice point is zero, setting the local kinematic viscosity at the current lattice point to be the temperature-corrected new asphalt viscosity value when the current phase-sequence parameter value at the current lattice point is one time, and setting the current phase-sequence parameter value at the current lattice point to be the temperature-corrected linear interpolation coefficient between the current phase-sequence parameter value and the current lattice point and the current phase-sequence parameter value.
6. The method according to claim 1, wherein the phase field updating substep in the second step is performed by, for any target lattice point in the calculation domain, obtaining a current phase field sequence parameter value of the target lattice point, obtaining current phase field sequence parameter values of the target lattice point in a horizontal positive direction adjacent lattice point, a horizontal negative direction adjacent lattice point, a vertical positive direction adjacent lattice point and a vertical negative direction adjacent lattice point, which are four adjacent phase field sequence parameter values in total, calculating an arithmetic average value of the four adjacent phase field sequence parameter values to obtain an adjacent average phase field sequence parameter value, and calculating a difference value between the adjacent average phase field sequence parameter value and the current phase field sequence parameter value of the target lattice point to obtain a phase field diffusion driving amount; obtaining a current flow velocity vector at a target lattice point, calculating the product of the difference between a current phase field sequence parameter value of a current flow velocity vector in a horizontal direction and a current phase field sequence parameter value of a horizontal positive direction adjacent lattice point and a current phase field sequence parameter value of a horizontal negative direction adjacent lattice point to obtain a horizontal convection transport volume, calculating the product of the difference between a current phase field sequence parameter value of a current flow velocity vector in a vertical direction and a current phase field sequence parameter value of a vertical positive direction adjacent lattice point and a current phase field sequence parameter value of a vertical negative direction adjacent lattice point to obtain a vertical convection transport volume, adding the horizontal convection transport volume and the vertical convection transport volume to obtain a total convection transport volume, multiplying the phase field diffusion drive volume by a preset phase field diffusion coefficient to obtain a diffusion update increment, multiplying the total convection transport volume by the preset convection update increment, adding the current phase field sequence parameter value of the target lattice point by the diffusion update increment and subtracting the convection update increment to obtain an updated phase field sequence parameter value, correcting the updated phase sequence parameter value to zero when the updated phase sequence parameter value is smaller than zero, and correcting the updated phase field sequence parameter value to be one when the updated phase field sequence parameter value is greater than one.
7. The method according to claim 4, wherein the lattice Boltzmann collision migration substep in the second step is performed by first performing a collision operation on any target lattice point in a calculation domain, calculating a local equilibrium distribution function value corresponding to the current particle distribution function according to a current macroscopic density value and a current flow velocity vector at the target lattice point for each particle distribution function at the target lattice point, calculating a difference value between the current particle distribution function value and the local equilibrium distribution function value to obtain a deviation balance value, calculating a relaxation time value according to a local kinematic viscosity value at the target lattice point, dividing the deviation balance value by the relaxation time value to obtain a collision adjustment value, subtracting the collision adjustment value from the current particle distribution function value to obtain a post-collision particle distribution function value, performing a migration operation after the collision operation is completed, migrating nine post-collision particle distribution functions corresponding to zero velocity directions to adjacent lattice points in discrete velocity directions respectively, summarizing the post-collision particle distribution functions corresponding to the current lattice points at the target lattice points after the migration operation is completed, adding nine particle distribution functions to obtain updated density values, multiplying the nine post-macroscopic distribution values by the respective velocity values, and multiplying the updated discrete velocity values by the respective velocity values after the addition of the discrete velocity values.
8. The method of claim 1, wherein step two further comprises setting boundary conditions at boundaries of the two-dimensional rectangular computational domain, setting periodic boundary conditions at upper and lower boundaries of the two-dimensional rectangular computational domain such that the particle distribution function that migrates from the upper boundary migrates from the lower boundary and the particle distribution function that migrates from the lower boundary migrates from the upper boundary, setting constant flow rate inlet boundary conditions at a left boundary of the two-dimensional rectangular computational domain, and setting constant pressure outlet boundary conditions at a right boundary of the two-dimensional rectangular computational domain.
9. The method of claim 1, wherein the external load condition formed by simulating rutting is characterized in that a central section is selected as a load application area at the upper boundary of a two-dimensional rectangular calculation area, a volume force source item in the downward direction is overlapped to a particle distribution function at each lattice point in the load application area, rutting resistance performance evaluation indexes comprise an old-new asphalt interface fusion index, a simulated maximum rutting depth index and a high-temperature flow activity index, the old-new asphalt interface fusion index is the percentage of the total number of lattice points of a two-dimensional rectangular calculation area, the number of lattice points is between a preset mixing judgment lower limit value and a mixing judgment upper limit value, the simulated maximum rutting depth index is the maximum value of the accumulated vertical displacement quantity of monitoring lattice points right below the load application area, and the high-temperature flow activity index is the percentage of the total number of lattice points, the flow velocity vector module value of which is larger than a preset flow threshold value, of the total number of lattice points of the two-dimensional rectangular calculation area.
10. The method of claim 9, wherein the specific mode of proportioning parameter regulation in the third step is to increase the blending amount of the warm mix agent or increase the mixing temperature when the interface fusion degree index of the new asphalt and the old asphalt is smaller than a preset fusion degree target threshold value, decrease the blending amount of the milling material or increase the proportion of hard components in the new asphalt when the simulated maximum rutting depth index is larger than a preset rutting depth allowable value, and increase the blending amount of the polymer modifier in the new asphalt when the high-temperature flow activity index is larger than a preset flow activity upper limit value.

Description

Anti-rutting regulation and control method for regenerating warm mix asphalt by large-mixing amount milling material Technical Field The invention relates to the technical field of automatic control, in particular to an anti-rutting regulation and control method for regenerating warm mix asphalt by using a large amount of milling materials, belonging to industrial control software. Background In the development process of the regenerated asphalt mixture technology, increasing the milling material mixing amount is always the focus of researchers. Early regeneration techniques, limited by the manufacturing process and mix design method, typically controlled milling stock loading between 15 and 25 percent. Along with the continuous progress of regeneration technology in recent years, part of engineering projects have promoted milling material doping amount to 40 percent or even more than 50 percent, and the large-doping amount regeneration technology can realize the recycling of milling material to the greatest extent. However, the old asphalt in the milled material has obvious aging after long-term service, and has the characteristics of reduced penetration, increased softening point and reduced ductility, and is hard and brittle as a whole. As the amount of milled material is increased, the proportion of aged asphalt in the mix increases, resulting in challenges in the high temperature stability, low temperature crack resistance and fatigue durability of the recycled mix. The existing method for designing the mixing ratio of the reclaimed asphalt mixture mainly depends on an indoor test and an empirical formula. The designer firstly selects proper new asphalt label according to the aging degree of old asphalt, then estimates the blending proportion of the new asphalt and the old asphalt through a penetration blending formula or a viscosity blending formula, and finally makes a test piece to carry out Marshall stability test or rutting test to verify the rationality of the design scheme. This test-based design approach has significant limitations. On the one hand, the indoor test period is long, the cost is high, and the screening and optimization of a large number of proportioning schemes are difficult to finish in a short time. On the other hand, the traditional test method can only acquire the mechanical property index of a macroscopic level, and cannot reveal the microcosmic fusion mechanism of a new asphalt interface and an old asphalt interface and the rheological behavior of asphalt under the action of load, and the design process lacks theoretical guidance. Disclosure of Invention The invention aims to provide the rutting resistance regulation method for regenerating warm mix asphalt by using a large amount of milling materials, realizes the coupling simulation of the diffusion evolution of the new asphalt interface and the old asphalt interface and the high-temperature viscous flow behavior, establishes a multi-dimensional rutting resistance evaluation system, can rapidly screen and optimize a proportioning scheme in a virtual environment, greatly shortens the design period and reduces the test cost, and provides scientific guidance for the proportioning design of the large amount of milling materials and regenerating warm mix asphalt mixture. In order to solve the technical problems, the invention provides the following technical scheme: The rut resistance control method for regenerating warm mix asphalt by using a large amount of milling materials comprises the following steps: Performing penetration test and softening point test on old asphalt in a milling material to obtain an old asphalt penetration value and an old asphalt softening point value, performing penetration test and softening point test on new asphalt to be blended to obtain a new asphalt penetration value and a new asphalt softening point value, and performing melting point test on a warm mixing agent to be blended to obtain a melting point value of the warm mixing agent; Establishing a two-dimensional rectangular calculation domain, dividing the two-dimensional rectangular calculation domain into a first calculation section, a second calculation section and a third calculation section along the horizontal direction, wherein the first calculation section represents an old asphalt phase region, the third calculation section represents a new asphalt phase region, the second calculation section represents a new and old asphalt interface transition region, establishing phase-sequence parameter distribution represents asphalt phase state attributes, establishing lattice Boltzmann velocity discrete lattice simulation asphalt flow behaviors, performing alternating iterative calculation of a phase-field updating sub-step and a lattice Boltzmann collision migration sub-step, applying external load conditions formed by simulating ruts, and extracting anti-rut performance evaluation indexes after iteration is completed; And thirdly, comparing