CN113702427B - Evaluation method for miscibility characteristics of new asphalt and old asphalt and regenerant in-situ thermal regeneration - Google Patents
Evaluation method for miscibility characteristics of new asphalt and old asphalt and regenerant in-situ thermal regeneration Download PDFInfo
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Abstract
The invention relates to a method for evaluating miscibility characteristics of new and old asphalt and a regenerant in-situ thermal regeneration, and belongs to the field of road engineering. Constructing a three-layer molecular dynamics model of new asphalt molecules, old asphalt molecules and regenerant miscibility in-situ thermal regeneration; drawing a relative concentration curve of new asphalt molecules, old asphalt molecules and regenerant molecules in the three-layer molecular dynamics model; calculating the relative concentration curves of new asphalt molecules, old asphalt molecules and regenerant molecules to obtain a new asphalt distribution area, an old asphalt distribution area and a regenerant distribution area after miscibility; calculating to obtain the action rate of the regenerant, the activation rate of the old asphalt and the proportion of the new asphalt and the old asphalt in the miscible area; evaluating the activation rate of the regenerants with the same type and different doping amounts or the regenerants with the same doping amount of different types and old asphalt, wherein the larger the activation rate is, the better the index is; the proportion of the regenerants with different doping amounts in the same category or the same doping amount in different categories in the same doping amount in the miscible area of the new asphalt and the old asphalt is evaluated, and the higher the activation rate is, the better the index is.
Description
Technical Field
The invention relates to a method for evaluating miscibility characteristics of new and old asphalt and a regenerant in-situ thermal regeneration, and belongs to the field of road engineering.
Background
According to the regulations of the technical Specification for recycling asphalt pavement of highway (JTG T5521-2019) in the in-situ heat recycling process, heating the milled old pavement asphalt mixture, adding a recycling agent, mixing for 5-10 seconds, adding new asphalt and new aggregate, mixing, spreading on site, and gradually cooling the recycled asphalt mixture to the room temperature. In the existing research method, in order to determine the miscibility of the new asphalt and the old asphalt, an indoor sample or a field test is needed to be carried out, in molecular dynamics analysis, the miscibility temperature is generally assumed to be a fixed value, the change of the miscibility temperature of the new asphalt and the old asphalt in the asphalt mixture in actual in-situ thermal regeneration is ignored, and the new asphalt and the old asphalt miscibility index based on molecular dynamics simulation is lacked. Based on the situation, the invention provides an evaluation method for the miscibility characteristics of the new asphalt and the old asphalt and the regenerant in the in-situ thermal regeneration, which is suitable for evaluating the miscibility characteristics of the new asphalt and the old asphalt and the regenerant in the preparation of the regeneration mixture in the in-situ thermal regeneration.
Disclosure of Invention
The invention provides an evaluation method for the miscibility characteristics of new and old asphalt and a regenerant in-situ thermal regeneration according to the defects.
The invention adopts the following technical scheme:
the invention relates to a method for evaluating miscibility characteristics of new asphalt, old asphalt and regenerant in-situ thermal regeneration, which comprises the following steps:
s1: constructing a three-layer molecular dynamics model of new asphalt molecules, old asphalt molecules and regenerant miscibility in-situ thermal regeneration; the regenerant is selected to be of the same type and different doping amounts or of different types and the same doping amount in the three-layer molecular dynamics model;
s2: aiming at the molecular dynamics simulation established in the step S1;
s3: calculating the relative concentration of each cross section of each molecule in the three-layer molecular dynamics model, and drawing a relative concentration curve of new asphalt molecules, old asphalt molecules and regenerant molecules in the three-layer molecular dynamics model;
s4: smoothing the relative concentration curve of new asphalt molecules, old asphalt molecules and regenerant molecules in the step S3;
s5: calculating the relative concentration curves of new asphalt molecules, old asphalt molecules and regenerant molecules to obtain a new asphalt distribution area, an old asphalt distribution area and a regenerant distribution area after miscibility;
s6: calculating to obtain the action rate of the regenerant, the activation rate of the old asphalt and the proportion of the new asphalt and the old asphalt mixing area through the new asphalt distribution area, the old asphalt distribution area and the regenerant distribution area;
evaluating the activation rate of the regenerants with the same type and different doping amounts or the regenerants with the same doping amount of different types and old asphalt, wherein the larger the activation rate is, the better the index is;
the proportion of the regenerants with different doping amounts in the same category or the same doping amount in different categories in the same doping amount in the miscible area of the new asphalt and the old asphalt is evaluated, and the higher the activation rate is, the better the index is.
The invention relates to a method for evaluating miscibility characteristics of new asphalt, old asphalt and regenerant in-situ thermal regeneration, which comprises the steps of (1) constructing a three-layer molecular dynamics model from left horizontal to right horizontal and l left To l right ；
New asphalt molecules, regenerant and old asphalt molecules are sequentially arranged in the left-right horizontal coordinate; performing system geometric balance after modeling;
both the new asphalt and the old asphalt and the regenerant are composed of various molecules; the novel asphalt molecules in the three-layer molecular dynamics model comprise 1 st to i th m The old asphalt molecules include the ith m+1 To the ith n The species, regenerant molecules include the ith n+1 To the ith p A kind of module is assembled in the module and the module is assembled in the module.
The invention relates to a method for evaluating miscibility characteristics of new asphalt, old asphalt and regenerant in-situ thermal regeneration, which is characterized by comprising the following steps: in the step S2:
adopting an NPT system to carry out molecular dynamics simulation aiming at the three-layer model built in the S1, simulating medium pressure and force field parameters, and determining by referring to the simulated parameters of the actual in-situ thermal regeneration engineering;
based on the temperature reduction curve of the asphalt mixture after paving obtained by actual measurement or numerical simulation, determining the system temperature in the molecular dynamics simulation through the following conditions:
if the time range of the actually measured or simulated cooling curve is 0-t 1 The total NPT ensemble time in molecular dynamics simulation is 0-t 2 The method comprises the steps of carrying out a first treatment on the surface of the Because the temperature cannot be set in NPT and continuously decreases, the temperature is 0-t 2 The NPT process of (2) corresponds to 0-t 1 The cooling curve and the NPT process are divided into N sections (N is more than or equal to 20) according to time average, and the temperature corresponding to the time midpoint of each section of cooling curve is used as the temperature set in each section of NPT.
The invention relates to a method for evaluating miscibility characteristics of new asphalt, old asphalt and regenerant in-situ thermal regeneration, which comprises the following steps of: after the molecular dynamics simulation is completed, the mass center position of each atom on each molecule is based on the output mass center position; dividing the three-layer molecular dynamics model into a plurality of cross sections, and calculating the relative concentration of new asphalt molecules, old asphalt molecules and regenerant molecules in each cross section in the model; for the abscissa in the model from l left -l right Wherein l is left Finger model left boundary position, l right Refers to the right boundary position of the model, and uniformly divides the model into the 1 st to M (M is more than or equal to 100) th areas from left to right along the abscissa direction, M is the most p In each transverse section, i (i is more than or equal to 1 and less than or equal to i) p ) Relative concentration of class molecules a (i, M p ) A kind of electronic deviceThe calculation method comprises the following steps:
wherein a (x) is the M < th p The total mass of atoms belonging to the ith class of molecules in each transverse section, b (x) being the centroid at M p Total mass of all atoms in each transverse segment.
The invention relates to a method for evaluating the miscibility characteristics of new and old asphalt and a regenerant in-situ thermal regeneration, which is M < th p In each cross section, the relative concentration of neobitumen molecules A (M p ) Relative concentration of old bitumen molecules B (M p ) Relative concentration of regenerant molecules C (M p ) The calculation method comprises the following steps:
calculating the relative concentration of new asphalt molecules, old asphalt molecules and regenerant molecules in the 1 st to M th transverse sections, drawing the relative concentration curves of the new asphalt molecules, the old asphalt molecules and the regenerant in the model in a plane rectangular coordinate system, and smoothing the curves by using a Gaussian filtering method to obtain the smoothed relative concentration curves of the new asphalt molecules, the old asphalt molecules and the regenerant.
The invention relates to a method for evaluating miscibility characteristics of new asphalt, old asphalt and regenerant in-situ thermal regeneration, which comprises the following steps of:
selecting a part with a relative concentration of more than 1% based on the smoothed relative concentration curve of the new asphalt molecules obtained in S4, and defining the corresponding range as new mixed asphalt moleculesThe pitch distribution area, i.e. the abscissa is in l left To l 3 Is a part of (2);
based on the smoothed relative concentration curve of the old asphalt molecules obtained in S4, selecting a part with the relative concentration being more than 1%, and defining the corresponding range as an old asphalt distribution area after miscibility, namely, the abscissa is l 2 To l right Is a part of (2);
selecting a part with a relative concentration greater than 1% based on the smoothed relative concentration curve of the new asphalt molecules obtained in S4, and defining the corresponding range as a regenerant distribution area after miscibility, namely the abscissa is l 1 To l 4 Is a part of (2); l (L) 2 To l 3 The part between the two parts contains new and old asphalt molecules, and is defined as a new and old asphalt miscibility gap. Part of the reason for choosing more than 1% is to avoid the influence of the centroid position of atoms on individual molecules with no statistical significance on the analysis results;
wherein, l left Is the left boundary position coordinate of the model, l right Is the right boundary position coordinate of the model, l mid Is the median position coordinate of the model, l 1 And l 4 The left and right position coordinates corresponding to the relative concentration curve of the regenerant in the model is 1%; l (L) 2 And l 3 The position coordinates corresponding to the relative concentration curves of the old asphalt and the new asphalt in the model are respectively 1 percent.
The invention relates to a method for evaluating miscibility characteristics of new asphalt, old asphalt and regenerant in-situ thermal regeneration, which comprises the following steps of: the regenerant action rate Z is the mass ratio of the regenerant diffused into the old asphalt to the total regenerant, and is calculated as follows:
wherein c is the total mass of atoms belonging to the regenerant molecules of the regenerant distribution area with centroid after miscibility, and d is the total mass of all atoms belonging to the regenerant molecules in the three-layer model.
The old asphalt activation rate J refers to the proportion of an old asphalt distribution area in which regenerant molecules are diffused after being mixed and dissolved to an old asphalt distribution area after being mixed, and the old asphalt activation rate J is calculated by the following method:
the ratio H of the new asphalt mixing area to the old asphalt mixing area refers to the ratio of the length of the new asphalt mixing area to the total length of the three-layer model, and the calculation method is as follows:
advantageous effects
The invention provides an evaluation method for the miscibility characteristics of new and old asphalt and a regenerant in-situ thermal regeneration, which is suitable for evaluating the miscibility characteristics of the new and old asphalt and the regenerant in the preparation of a regeneration mixture in-situ thermal regeneration from the aspect of molecular dynamics.
According to the method for evaluating the miscibility characteristics of the new asphalt and the old asphalt and the regenerant in the in-situ thermal regeneration, when the infiltration process of the new asphalt and the old asphalt under the action of the regenerant is judged by the traditional method, an indoor experiment is required, the activation effect of the regenerant on the old asphalt, the proportion of the regenerant and the range of the miscibility area of the new asphalt and the old asphalt are difficult to evaluate, and a simulation method for obtaining the three indexes is lacking at present. Aiming at the three indexes, three indexes of the action rate of the regenerant, the activation rate of the old asphalt and the proportion of the miscible area of the new asphalt and the old asphalt are respectively provided based on molecular dynamics simulation, the method can be used for comprehensively evaluating the action process of the new asphalt and the old asphalt under the action of the regenerant, and is convenient for optimizing the indexes such as the type of the regenerant, the doping amount of the new asphalt and the like in the regeneration process based on simulation results.
Drawings
Fig. 1 (a) is a schematic diagram of the three-layer model constructed in step S1.
FIG. 1 (b) is a schematic diagram of a model after simulation
FIG. 1 (c) is a graph showing the relative concentration of the new asphalt molecules, the old asphalt molecules and the regenerant after smoothing in step S4.
Fig. 2 is a cooling curve in the first embodiment.
FIG. 3 is a graph showing the effect rate Z of the regenerant and the activation rate J of old asphalt according to the blending amount of the regenerant in the first embodiment.
FIG. 4 is a graph showing the ratio H of the new asphalt to the old asphalt in the first embodiment according to the blending amount of the regenerant.
Detailed Description
In order to make the purpose and technical solutions of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which can be made by a person skilled in the art without creative efforts, based on the described embodiments of the present invention fall within the protection scope of the present invention.
The method is suitable for evaluating the miscibility characteristics of the new asphalt and the old asphalt and the regenerant in the in-situ thermal regeneration, and comprises the following 6 steps:
s1: constructing a three-layer molecular dynamics model of new and old asphalt and regenerant miscibility in-situ thermal regeneration;
s2: developing molecular dynamics simulation;
s3: calculating the relative concentration of each cross section of each molecule in the model, and drawing a relative concentration curve of each molecule in the three-layer model;
s4: drawing a smoothing relative concentration curve of new asphalt, old asphalt and regenerant;
s5: calculating a new asphalt distribution area, an old asphalt distribution area and a regenerant distribution area after mixing;
s6: and calculating the action rate Z of the regenerant, the activation rate J of the old asphalt and the proportion H of the new asphalt and the old asphalt in the miscible area.
As shown in FIG. 1 (a), the three-layer molecular dynamics model constructed in step S1 is constructed from left to right and the abscissa from l left To l right The new asphalt molecules, the regenerant and the old asphalt molecules are sequentially arranged from left to right, the proportion among the three is determined according to the corresponding proportion in the simulated actual in-situ thermal regeneration engineering, and the modeling is carried out firstlyThe system geometry was balanced. Both the new asphalt and the regenerant are composed of a plurality of molecules, wherein the new asphalt molecules comprise the 1 st to the i st in the model m The old asphalt molecules include the ith m+1 To the ith n The species, regenerant molecules include the ith n+1 To the ith p A kind of module is assembled in the module and the module is assembled in the module.
In step S2: and (3) carrying out molecular dynamics simulation based on the three-layer model built in the step (S1), wherein parameters such as pressure, force field and the like in the simulation are actually determined by referring to the simulated actual in-situ thermal regeneration engineering. In particular, the system temperature in the molecular dynamics simulation may be determined based on a measured or numerically simulated cooling profile of the post-paving asphalt mixture. If the time range of the actually measured or simulated cooling curve is 0-t 1 NPT ensemble time in molecular dynamics simulation is 0-t 2 Since the temperature cannot be set in NPT and continuously decreases, the temperature is 0-t 2 The NPT process of (2) corresponds to 0-t 1 The cooling curve and the NPT process are divided into N sections (N is more than or equal to 20) according to time average, and the temperature corresponding to the time midpoint of each section of cooling curve is used as the temperature set in each section of NPT.
As a preferred technical scheme of the invention, the detail of the step S3 is as follows: after the molecular dynamics simulation is completed, the centroid position of each atom on each molecule is output. The relative concentrations of each cross-sectional segment of each type of molecule in the model were calculated. For the abscissa in the model from 0-x p Uniformly dividing the region into 1 st to M (M.gtoreq.100) regions from left to right along the abscissa direction, wherein the width of each region is
Mth p In each transverse section, i (i is more than or equal to 1 and less than or equal to i) p ) Relative concentration of class molecules a (i, M p ) The calculation method of (2) is as follows:
a (x) is the M < th) p The total mass of atoms belonging to the i-th class of molecules in each transverse sectionThe quantity b (x) is the mass center at M p Total mass of all atoms in each transverse segment. Calculating the relative concentration of each transverse section, drawing the relative concentration curve of each molecule in the three-layer model in a plane rectangular coordinate system, and smoothing the curve by using a Gaussian filter method to obtain the smoothed relative concentration curve of the new asphalt molecule, the old asphalt molecule and the regenerant.
As a preferred technical scheme of the invention, the detail of the step S4 is as follows: mth p In each cross section, the relative concentration of neobitumen molecules A (M p ) Relative concentration of old bitumen molecules B (M p ) Relative concentration of regenerant molecules C (M p ) The calculation method comprises the following steps:
calculating the relative concentration of the new asphalt molecules, the old asphalt molecules and the regenerant molecules in the 1 st to M th transverse sections, drawing the relative concentration curves of the new asphalt molecules, the old asphalt molecules and the regenerant in the model in a plane rectangular coordinate system, and smoothing the curves by using a Gaussian filter method to obtain the smoothed relative concentration curves of the new asphalt molecules, the old asphalt molecules and the regenerant, as shown in fig. 1 (b).
As shown in fig. 1 (c): in step S5, based on the smoothed relative concentration curve of the new asphalt molecules obtained in step S4, selecting a part with a relative concentration greater than 1%, and defining the corresponding range as a new asphalt distribution area after miscibility, namely, the abscissa is l left To l 3 Is a part of (2); selecting a part with a relative concentration of more than 1% based on the smoothed relative concentration curve of the old asphalt molecules obtained in the step S4,the corresponding range is defined as the old asphalt distribution area after miscibility, i.e. the abscissa is in l 2 To l right Is a part of (2); selecting a part with a relative concentration greater than 1% based on the smoothed relative concentration curve of the new asphalt molecules obtained in S4, and defining the corresponding range as a regenerant distribution area after miscibility, namely the abscissa is l 1 To l 4 Is a part of (2); l (L) 2 To l 3 The part between the two parts contains new and old asphalt molecules, and is defined as a new and old asphalt miscibility gap. Part of the reason for choosing more than 1% is to avoid the influence of the centroid position of atoms on individual molecules that are not statistically significant on the analysis results.
As a preferred technical scheme of the invention, the detail of the step S6 is as follows: the regenerant action rate Z is the mass ratio of the regenerant diffused into the old asphalt to the total regenerant, and is calculated as follows:
wherein c is the total mass of atoms belonging to the regenerant molecules of the regenerant distribution area with centroid after miscibility, and d is the total mass of all atoms belonging to the regenerant molecules in the three-layer model.
The old asphalt activation rate J refers to the proportion of an old asphalt distribution area in which regenerant molecules are diffused after being mixed and dissolved to an old asphalt distribution area after being mixed, and the old asphalt activation rate J is calculated by the following method:
the ratio H of the new asphalt mixing area to the old asphalt mixing area refers to the ratio of the length of the new asphalt mixing area to the total length of the three-layer model, and the calculation method is as follows:
embodiment one:
and (3) performing hot in-situ regeneration on a certain place, wherein the mixing temperature is 160 ℃ (433K), and the temperature of the regenerated asphalt mixture layer after paving is reduced from 160 ℃ (433K) to 25 ℃ (298K). Compass-II force field and periodic boundary conditions are adopted in molecular dynamics simulation, the temperature is controlled by a Nose-Hoover thermostat, the pressure is controlled to be 1atm by an Anderson barostat, and the time step is 1fs. The NVT ensemble of 30ps is adopted, so that the system reaches the temperature required by simulation under the condition of relatively stable volume, thereby stabilizing energy and preventing the generation of energy singular. The 5ns NPT system is adopted to keep the temperature and pressure of the system at target values, and the diffusion and mixing process of the regenerant, the raw asphalt and the aged asphalt is simulated.
The time parameter in molecular dynamics is not consistent with the actual time, and has only relative significance. The cooling curve of the in-situ hot-in-place regenerated asphalt mixture pavement based on finite element simulation is shown in fig. 2, in order to reflect the influence of the cooling curve, the NPT process of 0-5ns is corresponding to the cooling process of 0-2h, the cooling curve is divided into 50 sections according to time, and the temperature corresponding to the time midpoint of each section of cooling curve is taken as the temperature set in each section of NPT. Under different amounts of regenerant, the obtained regenerant action rate Z and old asphalt activation rate J are shown in figure 3, and the proportion H of the new asphalt to the old asphalt mixing zone is shown in figure 4.
The present invention is not limited to the above-mentioned embodiments, and any changes or substitutions that can be easily understood by those skilled in the art within the technical scope of the present invention are intended to be included in the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
Claims (7)
1. The method for evaluating the miscibility characteristics of the new asphalt and the old asphalt and the regenerant in the in-situ thermal regeneration is characterized by comprising the following steps:
s1: constructing a three-layer molecular dynamics model of new asphalt molecules, old asphalt molecules and regenerant miscibility in-situ thermal regeneration; the regenerant is selected to be of the same type and different doping amounts or of different types and the same doping amount in the three-layer molecular dynamics model;
s2: aiming at the molecular dynamics simulation established in the step S1;
s3: calculating the relative concentration of each cross section of each molecule in the three-layer molecular dynamics model, and drawing a relative concentration curve of new asphalt molecules, old asphalt molecules and regenerant molecules in the three-layer molecular dynamics model;
s4: smoothing the relative concentration curve of new asphalt molecules, old asphalt molecules and regenerant molecules in the step S3;
s5: calculating the relative concentration curves of new asphalt molecules, old asphalt molecules and regenerant molecules to obtain a new asphalt distribution area, an old asphalt distribution area and a regenerant distribution area after miscibility;
s6: calculating to obtain the action rate of the regenerant, the activation rate of the old asphalt and the proportion of the new asphalt and the old asphalt mixing area through the new asphalt distribution area, the old asphalt distribution area and the regenerant distribution area;
evaluating the activation rate of the regenerants with the same type and different doping amounts or the regenerants with the same doping amount of different types and old asphalt, wherein the larger the activation rate is, the better the index is;
the proportion of the regenerants with different doping amounts in the same category or the same doping amount in different categories in the same doping amount in the miscible area of the new asphalt and the old asphalt is evaluated, and the higher the activation rate is, the better the index is.
2. The method for evaluating miscibility characteristics of a new asphalt and a used asphalt and a regenerant in-situ thermal regeneration according to claim 1, wherein the method comprises the steps of: the three-layer molecular dynamics model built in the step S1 is from left abscissa to right abscissa from l left To l right ；
l left Is the left boundary position coordinate of the model, l rig h t The right boundary position coordinates of the model;
new asphalt molecules, regenerant and old asphalt molecules are sequentially arranged in the left abscissa to the right abscissa; performing system geometric balance after modeling;
both the new asphalt and the old asphalt and the regenerant are composed of various molecules; the novel asphalt molecules in the three-layer molecular dynamics model comprise 1 st to i th m The old asphalt molecules include the ith m+1 To the ith n The species, regenerant molecules include the ith n+1 To the ith p A kind of module is assembled in the module and the module is assembled in the module.
3. The method for evaluating miscibility characteristics of a new asphalt and a used asphalt and a regenerant in-situ thermal regeneration according to claim 1, wherein the method comprises the steps of: in the step S2:
adopting an NPT system to carry out molecular dynamics simulation aiming at the three-layer model built in the S1, simulating medium pressure and force field parameters, and determining by referring to the simulated parameters of the actual in-situ thermal regeneration engineering;
based on the temperature reduction curve of the asphalt mixture after paving obtained by actual measurement or numerical simulation, determining the system temperature in the molecular dynamics simulation through the following conditions:
if the time range of the actually measured or simulated cooling curve is 0-t 1 The total NPT ensemble time in molecular dynamics simulation is 0-t 2 The method comprises the steps of carrying out a first treatment on the surface of the Will be 0-t 2 The NPT process of (2) corresponds to 0-t 1 The cooling curve and the NPT process are divided into N sections in time average, N is more than or equal to 20, and the temperature corresponding to the time midpoint of each section of cooling curve is used as the temperature set in each section of NPT.
4. The method for evaluating miscibility characteristics of a new asphalt and a regenerant in-situ thermal regeneration according to claim 1 or 2, wherein: the step S3 is specifically as follows: after the molecular dynamics simulation is completed, the mass center position of each atom on each molecule is based on the output mass center position; dividing the three-layer molecular dynamics model into a plurality of cross sections, and calculating the relative concentration of new asphalt molecules, old asphalt molecules and regenerant molecules in each cross section in the three-layer molecular dynamics model; for the abscissa in the model from l left -l right Wherein l is left Finger model left boundary position, l right Refers to the right boundary position of the model, and uniformly divides the model into 1 st to M th areas from left to right along the abscissa direction, wherein M is more than or equal to 100, and M is the th area p In each transverse section, the i-th class of molecules, wherein i is more than or equal to 1 and less than or equal to i p, i relative concentration a (i, M p ) The calculation method of (2) is as follows:
wherein a (x) is the M < th p The total mass of atoms belonging to the ith class of molecules in each transverse section, b (x) being the centroid at M p Total mass of all atoms in each transverse segment.
5. The method for evaluating the miscibility characteristics of a new asphalt and a regenerant in-situ thermal regeneration according to claim 4, wherein the method comprises the steps of: mth p In each cross section, the relative concentration of neobitumen molecules A (M p ) Relative concentration of old bitumen molecules B (M p ) Relative concentration of regenerant molecules C (M p ) The calculation method comprises the following steps:
calculating the relative concentration of new asphalt molecules, old asphalt molecules and regenerant molecules in the 1 st to M th transverse sections, drawing the relative concentration curves of the new asphalt molecules, the old asphalt molecules and the regenerant in the model in a plane rectangular coordinate system, and smoothing the curves by using a Gaussian filtering method to obtain the smoothed relative concentration curves of the new asphalt molecules, the old asphalt molecules and the regenerant.
6. The method for evaluating miscibility characteristics of a new asphalt and a regenerant in-situ thermal regeneration according to claim 1 or 5, wherein the method comprises the steps of: the step S5 is specifically as follows:
selecting a part with a relative concentration of more than 1% based on the smoothed relative concentration curve of the new asphalt molecules obtained in S4, and performing corresponding rangeDefined as the new asphalt distribution area after miscibility, i.e. the abscissa is in l left To l 3 Is a part of (2);
based on the smoothed relative concentration curve of the old asphalt molecules obtained in S4, selecting a part with the relative concentration being more than 1%, and defining the corresponding range as an old asphalt distribution area after miscibility, namely, the abscissa is l 2 To l right Is a part of (2);
selecting a part with a relative concentration greater than 1% based on the smoothed relative concentration curve of the regenerant molecules obtained in S4, and defining the corresponding range as a regenerant distribution area after miscibility, namely the abscissa is l 1 To l 4 Is a part of (2); l (L) 2 To l 3 The part between the two parts simultaneously contains new and old asphalt molecules, the new and old asphalt molecules are defined as new and old asphalt miscible areas, and the part of the reason for selecting more than 1 percent is that the influence of the mass center position of atoms on individual molecules without statistical significance on analysis results is avoided;
wherein l left Is the left boundary position coordinate of the model, l right Is the right boundary position coordinate of the model, l mid Is the median position coordinate of the model, l 1 And l 4 The left and right position coordinates corresponding to the relative concentration curve of the regenerant in the model is 1%; l (L) 2 And l 3 The position coordinates corresponding to the relative concentration curves of the old asphalt and the new asphalt in the model are respectively 1 percent.
7. The method for evaluating miscibility characteristics of a new asphalt and a used asphalt and a regenerant in-situ thermal regeneration according to claim 1, wherein the method comprises the steps of: the step S6 is specifically as follows: the regenerant action rate Z is the mass ratio of the regenerant diffused into the old asphalt to the total regenerant, and is calculated as follows:
wherein c is the total mass of atoms belonging to the regenerant molecules in the regenerant distribution area after the centroid is mixed and d is the total mass of all atoms belonging to the regenerant molecules in the three-layer model;
the old asphalt activation rate J refers to the proportion of an old asphalt distribution area in which regenerant molecules are diffused after being mixed and dissolved to an old asphalt distribution area after being mixed, and the old asphalt activation rate J is calculated by the following method:
the ratio H of the new asphalt mixing area to the old asphalt mixing area refers to the ratio of the length of the new asphalt mixing area to the total length of the three-layer model, and the calculation method is as follows:
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