CN-121978318-A - Structure-efficiency-relation-based low-loss evaluation method for hardening of service asphalt pavement

CN121978318ACN 121978318 ACN121978318 ACN 121978318ACN-121978318-A

Abstract

A method for evaluating hardening low loss of a service asphalt pavement based on a structure-activity relationship. The invention provides a quantitative evaluation method for modified asphalt performance in a mixture under the premise of not damaging a pavement structure, which comprises the steps of after obtaining an old pavement modified asphalt type, correspondingly configuring at least three homologous modified asphalt types according to the old pavement modified asphalt type, obtaining a modulus change index MCI through correlation test and calculation, obtaining a functional group change index FCI after carrying out correlation analysis and calculation on the old pavement modified asphalt type, constructing an MCI-FCI correlation equation according to MCI and FCI data, and combining the MCI-FCI correlation equation and FTIR analysis to complete a quantitative analysis and evaluation process for service performance of the old modified asphalt pavement.

Inventors

LI TIANSHUAI
WU WENLONG
YANG TIAN
JIAO XIAOLEI
HUANG DANDAN

Assignees

河北工业大学

Dates

Publication Date: 20260505
Application Date: 20260120

Claims (6)

1. A method for evaluating the hardening of the serving asphalt pavement based on the structure-activity relation is characterized in that after the old pavement modified asphalt type is obtained, at least three kinds of homologous modified asphalt are correspondingly configured according to the old pavement modified asphalt type, a modulus change index MCI is obtained through correlation test and calculation, the old pavement modified asphalt type is subjected to correlation analysis and calculation to obtain a functional group change index FCI, an MCI-FCI correlation equation is constructed according to the MCI and FCI data, and the MCI-FCI correlation equation and FTIR analysis are combined to complete the quantitative analysis and evaluation process of the serving performance of the old modified asphalt pavement.
2. The method for evaluating the hardening low loss of the serving asphalt pavement based on the structure-activity relationship according to claim 1 is characterized in that after the old pavement modified asphalt type is obtained, at least three kinds of homologous modified asphalt are correspondingly configured according to the old pavement modified asphalt type, and the value range of the difference between the ageing degree percentages of two adjacent homologous modified asphalt is 1% -1.5%: after sequentially performing a rotating film oven test, a pressure aging test and a rheology test on each old pavement homologous modified asphalt, each asphalt sample is correspondingly formed with a modulus change index MCI after passing the rheology test and calculating, and the calculating process is as follows: each asphalt sample is subjected to temperature-frequency scanning, and the selected asphalt samples are used And 10 4 Hz reduced frequency is used as an integral limit value, and according to a complex modulus main curve under a double-logarithmic coordinate system, the modulus change index MCI of the modified asphalt sample is calculated and obtained, wherein the MCI calculation formula is as follows: ; In the above-mentioned method, the step of, Taking logarithm of the unaged asphalt to reduce frequency; Taking logarithm of the aged asphalt to reduce frequency; is the dynamic shear modulus.
3. The method for evaluating the hardening low loss of the serving asphalt pavement based on the structure-activity relationship according to claim 1 or 2, wherein an actual old pavement modified asphalt sample is obtained, the mass of the actual old pavement modified asphalt sample is less than or equal to 1 gram, an attenuated total reflection ATR mode of Fourier transform infrared spectrum FTIR is adopted to obtain an infrared spectrum band of the actual old pavement modified asphalt, the spectral aging fingerprints of the amide band a and sulfoxide b functional groups of the actual old pavement modified asphalt are subjected to peak-dividing fitting treatment to obtain peak areas of corresponding absorption peaks, and a Gaussian-Lorentzian function is adopted to obtain peak areas of corresponding absorption peaks The FTIR spectrogram in the range is analyzed, and the functional group change index FCI is quantitatively calculated, wherein the calculation formula is as follows: ; In the above formula, FCI is the index of change of functional groups, and FI is the aging index.
4. The method for evaluating the hardening low loss of the service asphalt pavement based on the structure-activity relationship according to claim 3, wherein the method is characterized in that the peak area of the corresponding absorption peak is obtained after the spectral aging fingerprints of the amide band a and sulfoxide b functional groups of the actual old pavement modified asphalt are subjected to peak-by-peak fitting treatment, and the peak area is obtained through a Gaussian-Lorentzian function In the process of analyzing the FTIR spectrogram in the range, firstly, the areas of absorption peaks corresponding to a (i), a (ii) and b are obtained, and the carbonyl AI a and sulfoxide AI b indexes are calculated, wherein the calculation formula is as follows: ; ; ; in the above, A 1700 is The absorption peak area at the position A 1650 is The absorption peak area at the position A 1030 is The absorption peak area at the position, A ref2 is the reference absorption peak area.
5. The method for evaluating the hardening of a service asphalt pavement based on a structure-activity relationship according to claim 4, wherein the method is characterized in that the carbonyl and sulfoxide group indexes of the asphalt sample after RTFO and PAV aging are calculated and divided by the indexes of the unaged asphalt sample to obtain the corresponding characteristic functional groups According to the change index, correspondingly drawing a functional group change index histogram to analyze functional groups influencing asphalt aging, wherein the calculation formula is as follows: ; ; ; In the above formula, AI a (i), unaged is an index of unaged asphalt a (i), AI a (ii), unaged is an index of unaged asphalt a (ii), AI b,unaged is an index of unaged asphalt b, AI a (i), aged is an index of aged asphalt a (i), AI a (ii), aged is an index of aged asphalt a (ii), AI b , aged is an index of aged asphalt b, FI a (i) is an index of aging a (i), FI a (ii) is an index of aging a (ii), and FI b is an index of aging b.
6. The method for evaluating the hardening low loss of the serving asphalt pavement based on the structure-activity relationship is characterized by comprising the steps of fitting the obtained MCI and FCI data, establishing an MCI-FCI correlation equation, drawing a scatter diagram by taking an MCI value as an ordinate and a corresponding FCI value as an abscissa, observing a fitting result, determining a correlation index of the fitted equation, verifying the correlation between the MCI and the FCI, indicating that the correlation exists between the MCI and the FCI when the correlation index of the fitted equation is more than 85%, correspondingly determining that the serving performance of the actual old pavement modified asphalt is excellent, indicating that the correlation does not exist between the MCI and the FCI when the correlation index of the fitted equation is less than 85%, and correspondingly determining that the serving performance of the actual old pavement modified asphalt is declined.

Description

Structure-efficiency-relation-based low-loss evaluation method for hardening of service asphalt pavement Technical Field The invention particularly relates to a low-loss evaluation method for hardening of a service asphalt pavement based on a structure-activity relationship. Background The modified asphalt is widely applied to important traffic infrastructures such as expressways, urban arterial roads and the like by virtue of excellent high-low temperature stability, fatigue resistance and rut resistance. However, with the increase of the service time, the performance of the modified asphalt is gradually attenuated under the combined action of multiple factors such as vehicle load, natural environment such as solar radiation, rain wash, temperature fluctuation, and self chemical characteristic change. The modifier in the asphalt can be degraded and isolated or the compatibility with the asphalt matrix is reduced, so that the original excellent performance is greatly reduced, and the pavement is easy to suffer from cracks, pits and other diseases, thereby directly influencing the service life of the road and the driving safety. In order to accurately evaluate the actual condition of the old modified asphalt pavement, a maintenance strategy is scientifically formulated, resource waste caused by blind renovation is avoided, and the system performance detection of the old modified asphalt is particularly important. However, at present, to detect the performance of the modified asphalt pavement which has been in service for many years, a great amount of pavement materials are required to be obtained and the modified asphalt in the mixture is separated, so that not only is a great amount of economic loss caused by pavement damage, but also the situation that part of polymer modifiers are degraded or not easily dissolved by solvents and the like in the aging process occurs, and most of common reagents for detecting the performance of the separated modified asphalt are solvents harmful to people, such as trichloroethylene, toluene, gasoline and the like, so that the difficulty of separating the modified asphalt in the mixture is greatly increased. At present, related researches are still under exploration on a method for easily measuring the performance of modified asphalt in a mixture on the premise of not damaging the pavement structure so as to meet the requirements of different pavement workers Cheng Xuqiu. At present, the core reasons and technical problems that the actual pavement modified asphalt is difficult to precisely quantify and evaluate have challenges are mainly three points: Firstly, asphalt pavement service performance is under the combined action of multiple factors such as load, environment, asphalt grade or aggregate grading material characteristics, and the factors are mutually coupled, so that the influence weight of a single factor is difficult to split. Secondly, pavement performance attenuation is a dynamic process, such as the abrasion and damage degree differences of different road sections of intersections, slopes and straight line sections are large, single-point detection data cannot represent the whole level of the road sections, and the cost and the technical threshold of long-term continuous monitoring are high. Third, the limitation of the detection technology, such as the fact that partial performance indexes of pavement fatigue performance, water stability and the like cannot be obtained through simple on-site rapid detection, fitting calculation needs to be carried out by combining indoor tests and on-site data, meanwhile, the accuracy and operation standardization of detection equipment can directly influence the accuracy of quantized data, and the detection results of different equipment are different. In summary, a quantitative evaluation method for the performance of modified asphalt in a mixture on the premise of not damaging the pavement structure is lacking at present Disclosure of Invention The invention provides a structure-activity relationship-based low-loss evaluation method for hardening of a service asphalt pavement, which aims to solve the problems. According to the method, after the old pavement modified asphalt type is obtained, at least three kinds of homologous modified asphalt are correspondingly configured according to the old pavement modified asphalt type, a modulus change index MCI is obtained through correlation test and calculation, the old pavement modified asphalt type is subjected to correlation analysis and calculation to obtain a functional group change index FCI, an MCI-FCI correlation equation is constructed according to MCI and FCI data, and the MCI-FCI correlation equation and FTIR analysis are combined to complete a quantitative analysis and evaluation process of the service performance of the old modified asphalt pavement. After the old pavement modified asphalt type is obtained, correspondingly configuring at least three kinds of homologous