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The purpose of this study was to investigate the adhesive properties of polyphosphoric acid compounded SBS (PPA/SBS) modified asphalt. Three base asphalt binders, one SBS, one dibutyl phthalate (DBP), one furfural extraction oil, and two polyphosphoric acids (PPA), were used to produce the modified binders. The adhesive properties tested in this study included contact angle, cohesive work, adhesive work, and peak area ratio. Cohesive work and adhesive work indicators were calculated from the contact angle, the contact angle between PPA/SBS modified asphalt and three liquids (distilled water, glycerin, formamide) were tested by the contact angle tester, and the peak area ratio of the microscopic adhesion performance index by AFM. The relation between the microscopic adhesion performance characterization method (peak area ratio) and the macroscopic adhesion performance index (cohesive work, adhesion work) was established. The test results indicated that the PPA/SBS modified asphalt had the highest cohesive work and adhesion work under the conditions of 0.5% PPA, 1% DBP, 1.5% extracted oil, and 3.5% SBS, which was clearly greater than the original SBS modified asphalt, while the peak area ratio was consistent with the cohesive work and adhesive work, in which the correlation coefficient between the peak area ratio and cohesive work was 0.77788, and that between the peak area ratio and adhesion work was 0.87203. We recommend adopting the peak area ratio to characterize PPA/SBS modified asphalt’s microscopic adhesion properties.
Liangying Li; Zhiwei Li; Yongning Wang; Xiaolan Li; Bo Li. Relation Between Adhesion Properties and Microscopic Characterization of Polyphosphoric Acid Composite SBS Modified Asphalt Binder. Frontiers in Materials 2021, 8, 1 .
AMA StyleLiangying Li, Zhiwei Li, Yongning Wang, Xiaolan Li, Bo Li. Relation Between Adhesion Properties and Microscopic Characterization of Polyphosphoric Acid Composite SBS Modified Asphalt Binder. Frontiers in Materials. 2021; 8 ():1.
Chicago/Turabian StyleLiangying Li; Zhiwei Li; Yongning Wang; Xiaolan Li; Bo Li. 2021. "Relation Between Adhesion Properties and Microscopic Characterization of Polyphosphoric Acid Composite SBS Modified Asphalt Binder." Frontiers in Materials 8, no. : 1.
Although the quality inspection method of polycarboxylate superplasticizers (PCE) based on macroperformance is still widely used, it has the drawbacks of time-consuming and low precision. This study aims to develop a practicable alternative method for quality inspection of PCE. For this, spectra collection, feature extraction, and cluster analysis were performed up on the PCE samples to demonstrate the feasibility of the method. Also, a new similarity calculation method was introduced in this work. Results show that the solid PCE sample for spectrum collection can be prepared using the simple heating method. High-quality spectra can be rapidly collected by infrared spectrometer combined with ATR accessory. Meanwhile, the accuracy of classification and clustering is high, suggesting that the feature extraction method based on principal component analysis (PCA) is effective. In addition, compared with conventional similarity calculation methods of cosine angle and correlation coefficient, the new similarity calculation method achieves better classification results and better generalization ability. This work provides a method of quantitative analysis and rapid identification of PCE for the construction site.
Zhiwei Li; Bo Li; Zhizhong Zhao; Weizhong Ma; Wenju Li; Jiadong Wang. Rapid Identification and Quantitative Analysis of Polycarboxylate Superplasticizers Using ATR-FTIR Spectroscopy Combined with Chemometric Methods. Mathematical Problems in Engineering 2021, 2021, 1 -13.
AMA StyleZhiwei Li, Bo Li, Zhizhong Zhao, Weizhong Ma, Wenju Li, Jiadong Wang. Rapid Identification and Quantitative Analysis of Polycarboxylate Superplasticizers Using ATR-FTIR Spectroscopy Combined with Chemometric Methods. Mathematical Problems in Engineering. 2021; 2021 ():1-13.
Chicago/Turabian StyleZhiwei Li; Bo Li; Zhizhong Zhao; Weizhong Ma; Wenju Li; Jiadong Wang. 2021. "Rapid Identification and Quantitative Analysis of Polycarboxylate Superplasticizers Using ATR-FTIR Spectroscopy Combined with Chemometric Methods." Mathematical Problems in Engineering 2021, no. : 1-13.
Although crumb rubber modified asphalt (CRMA) has a better performance than matrix asphalt (MA) in road engineering, the application bottlenecks of this material lies in its high viscosity, poor workability and bad storage stability. Microwave technology is one of the solutions to the above problems. The objective of this study was to investigate the physical and chemical changes before and after aging of CRMA which was prepared by microwave activated crumb rubber, and the aging mechanism of microwave-activated crumb rubber modified asphalt (MACRMA). Through penetration, softening point, ductility, viscosity and DSR test, the high and low temperature performance and temperature sensitivity of MA, CRMA and MACRMA before and after aging were studied. These tests results revealed that microwave treatment can improve the anti-rutting ability and the anti-aging performance of rubber asphalt. According to gel permeation chromatography (GPC) test, the distribution changes of the internal molecular content of the three asphalts were determined during the aging process. Its test results showed that aging effect accelerated the conversion of small molecules to large molecules in asphalt, and the value of large molecular size (LMS) increases more after long-term aging. The microwave activation made the swelling reaction more intense, thereby delayed the conversion of LMS in the rubber asphalt. In addition, LMS has a high correlation with test indicators. The fourier transform infrared spectroscopy (FTIR) test was used to measure the functional group changes of each asphalt. The FTIR spectra indicated that microwave activation is mainly a process of physical change. The carbonyl and sulfoxide functional group indices of MACRMA were lower than those of MA and CRMA, which also confirmed that MACRMA has a better anti-aging ability.
Tao Zhou; Jianing Zhou; Qidong Li; Bo Li. Aging Properties and Mechanism of Microwave-Activated Crumb Rubber Modified Asphalt Binder. Frontiers in Materials 2020, 7, 1 .
AMA StyleTao Zhou, Jianing Zhou, Qidong Li, Bo Li. Aging Properties and Mechanism of Microwave-Activated Crumb Rubber Modified Asphalt Binder. Frontiers in Materials. 2020; 7 ():1.
Chicago/Turabian StyleTao Zhou; Jianing Zhou; Qidong Li; Bo Li. 2020. "Aging Properties and Mechanism of Microwave-Activated Crumb Rubber Modified Asphalt Binder." Frontiers in Materials 7, no. : 1.
Crumb rubber modifier (CRM) has been applied widely in modified asphalt production in the pavement industry and demonstrates many performance advantages. Further, its use makes it possible to recycle scrap tires and reduce the consumption of raw materials. However, CRM asphalt mixtures demand higher construction temperatures than do conventional asphalt mixtures because the CRM asphalt binder has higher viscosity, which increases energy consumption, emission of greenhouse gases, and disintegration of the crumb rubber. In this study, sodium hypochlorite (NaClO) was introduced to functionalize the CRM particles’ surface to alleviate these associated problems. The CRM particles’ surface was activated using different amounts of NaClO, and the microscopic morphology of the activated CRM was measured using scanning electron microscopy (SEM). The size characteristics of the two types of CRM (activated and inactivated) were measured using the Brunauer, Emmett, and Teller (BET) test. The Brookfield viscosity at 180°C and rheological properties of CRM asphalt binders with different activated CRM were measured. In addition, the correlation between pore size characteristic and rheological properties was calculated statistically. Subsequently, a rougher surface microscopic morphology was observed for CRM activated with NaClO solution than without. The pore characteristics’ indices (cumulative pore volume, cumulative pore area, most probable pore size, and mean pore size) decreased generally with lower amounts of NaClO and then increased when the NaClO exceeded a certain amount. Using NaClO solution to produce activated CRM can improve both the workability and rutting resistance issues associated with the application of CRM asphalt binder. The test results and correlation analysis indicated that the pore characteristics are a key factor for activated CRM to reduce viscosity values and increase the rutting factor significantly.
Bo Li; Qidong Li; Xuwei Zhu; Yongzheng Wei; Zhiwei Li; Dingbang Wei. Effect of Sodium Hypochlorite-Activated Crumb Rubber on Rheological Properties of Rubber-Modified Asphalt. Journal of Materials in Civil Engineering 2020, 32, 04020326 .
AMA StyleBo Li, Qidong Li, Xuwei Zhu, Yongzheng Wei, Zhiwei Li, Dingbang Wei. Effect of Sodium Hypochlorite-Activated Crumb Rubber on Rheological Properties of Rubber-Modified Asphalt. Journal of Materials in Civil Engineering. 2020; 32 (11):04020326.
Chicago/Turabian StyleBo Li; Qidong Li; Xuwei Zhu; Yongzheng Wei; Zhiwei Li; Dingbang Wei. 2020. "Effect of Sodium Hypochlorite-Activated Crumb Rubber on Rheological Properties of Rubber-Modified Asphalt." Journal of Materials in Civil Engineering 32, no. 11: 04020326.
Styrene-butadiene-styrene (SBS) modified bitumen is widely applied to the construction of high-grade pavement because of its good pavement properties. However, with the rising price of SBS polymer, SBS modified bitumen is more expensive. By adding the cheap modifier polyphosphoric acid (PPA) to bitumen and compounding with SBS, the production price of SBS modified bitumen is obviously reduced, and the miscibility between SBS and bitumen is promoted. In this study, the effect of base bitumen type, PPA type and raw materials content on the adhesion performance of polyphosphoric acid compounded SBS (PPA/SBS) modified bitumen was evaluated quantitatively using the contact angle test and surface free energy method. Three different bituminous materials, two types of PPA, SBS, stabilizer, compatibilizer and dibutyl phthalate (DBP) were used as raw materials to prepare PPA/SBS modified bitumen. The results indicate that PPA improves the adhesion of PPA/SBS modified bitumen, but with an increase in PPA content above a certain value, the cohesion work, adhesion work and compatibility ratio of PPA/SBS modified bitumen decrease gradually and the peeling work increases gradually. In the blending process of PPA and SBS, changes in adhesion performance depend mainly on the base bitumen type, PPA type and raw material content. Using SK 90# base bitumen; 105% PPA; and PPA, DBP, extraction oil, and SBS contents of 0.5%, 1%, 1.5%, and 3.5%, respectively, the water damage resistance of PPA/SBS modified bitumen is considerably improved.
Bo Li; Xiaolan Li; Marie Judith Kundwa; Zhiwei Li; Dingbang Wei. Evaluation of the adhesion characteristics of material composition for polyphosphoric acid and SBS modified bitumen based on surface free energy theory. Construction and Building Materials 2020, 266, 121022 .
AMA StyleBo Li, Xiaolan Li, Marie Judith Kundwa, Zhiwei Li, Dingbang Wei. Evaluation of the adhesion characteristics of material composition for polyphosphoric acid and SBS modified bitumen based on surface free energy theory. Construction and Building Materials. 2020; 266 ():121022.
Chicago/Turabian StyleBo Li; Xiaolan Li; Marie Judith Kundwa; Zhiwei Li; Dingbang Wei. 2020. "Evaluation of the adhesion characteristics of material composition for polyphosphoric acid and SBS modified bitumen based on surface free energy theory." Construction and Building Materials 266, no. : 121022.
Warm-mixed asphalt (WMA) has the characteristics of low mixing temperature and energy consumption, which makes it more suitable than hot-mixed asphalt for plateau regions (the altitude is above 500 m, and the terrain is relatively flat or has a wide area with certain undulations). However, WMA is subject to severe ultraviolet (UV) aging because the UV radiation in plateau areas is more intense. The asphalt’s aging changes its rheological properties inevitably, and thus degrades the asphalt pavement’s performance. Accordingly, the purpose of this paper is to investigate the effect of UV and oxygen coupling aging on WMA’s rheological properties and functional group index. Temperature and frequency sweep tests were performed with a dynamic shear rheometer. At the same time, the functional group index was used as an indicator to compare the changes in the WMA’s infrared spectrum before and after UV aging. The results showed that WMA’s elasticity increased and its viscosity decreased after aging with UV. Under the condition of UV–oxygen isolation, as the aging period increased, the WMA’s rutting factor increased gradually. The degree of improvement was greater than that under the condition of oxygen isolation. In contrast, the time required for the WMA’s complex shear modulus to recover under the condition of UV–oxygen coupling was delayed. An increase in the peak value of infrared spectrum indicates that the WMA has undergone oxygen aging. The presence and change in the carbonyl group reflects the degree of the WMA’s UV aging, and the UV aging condition had a greater effect on the peak values of the carbonyl and sulfoxide groups.
Hailian Li; Peipei Tong; Xijun Zhang; Xixiong Lin; Bo Li. Influence of Ultraviolet and Oxygen Coupling Aging on Rheological Properties and Functional Group Index of Warm Mix Asphalt Binder. Materials 2020, 13, 4216 .
AMA StyleHailian Li, Peipei Tong, Xijun Zhang, Xixiong Lin, Bo Li. Influence of Ultraviolet and Oxygen Coupling Aging on Rheological Properties and Functional Group Index of Warm Mix Asphalt Binder. Materials. 2020; 13 (19):4216.
Chicago/Turabian StyleHailian Li; Peipei Tong; Xijun Zhang; Xixiong Lin; Bo Li. 2020. "Influence of Ultraviolet and Oxygen Coupling Aging on Rheological Properties and Functional Group Index of Warm Mix Asphalt Binder." Materials 13, no. 19: 4216.
To explore the effect of ultraviolet (UV) aging on the adhesion properties of warm mix asphalt (WMA), WMA binders were prepared by adding Evotherm M1 and Sasobit into base asphalt. The base asphalt and two WMA binders were aged using a self-made UV aging box after a rolling thin-film oven test (RTFOT). As a comparison, pressure aging vessel (PAV) tests were performed for asphalt binders after RTFOT. The contact angles between the WMA binder and distilled water, glycerol, and formamide, before and after UV aging, were measured using the sessile drop method. On the basis of the surface free energy (SFE) theory, the SFE and its components, cohesion work, adhesion work, peeling work, and compatibility rate, before and after the UV aging of WMA, were obtained. The results show that the contact angle between WMA and water gradually increases with the degree of UV aging, which indicates that the aging increases the hydrophobicity of asphalt. After the RTFOT aging, UV aging at different times, and PAV aging, the SFE and its component, as well as cohesion work for all asphalt binders were reduced. The attenuation was severe after UV aging, followed by PAV aging and RTFOT aging. With the extension of UV aging time, the adhesion work, hot mix asphalt, and limestone aggregate compatibility rate gradually reduced, the peeling work increased, and the overall adhesion performance became poor. Under the aging effect of RTFOT and PAV, the Evotherm M1 WMA had the strongest anti-peeling ability, better compatibility, and the best adhesion. When the UV aging time of Sasobit WMA reached 100 h, the adhesion performance increased.
Bo Li; Yu Wang; Xiaoyu Ren; Xuqiu Teng; Xiuli Su. Influence of Ultraviolet Aging on Adhesion Performance of Warm Mix Asphalt Based on the Surface Free Energy Theory. Applied Sciences 2019, 9, 2046 .
AMA StyleBo Li, Yu Wang, Xiaoyu Ren, Xuqiu Teng, Xiuli Su. Influence of Ultraviolet Aging on Adhesion Performance of Warm Mix Asphalt Based on the Surface Free Energy Theory. Applied Sciences. 2019; 9 (10):2046.
Chicago/Turabian StyleBo Li; Yu Wang; Xiaoyu Ren; Xuqiu Teng; Xiuli Su. 2019. "Influence of Ultraviolet Aging on Adhesion Performance of Warm Mix Asphalt Based on the Surface Free Energy Theory." Applied Sciences 9, no. 10: 2046.
Crumb rubber modified (CRM) asphalt binder has been affirmed to improve resistance to rutting, moisture susceptibility, low-temperature cracking, and asphalt durability. However, CRM has poor compatibility with asphalt since crumb rubber molecules are vulcanized. The objective of this study was to develop a new method to prepare activated crumb rubber using hydrogen peroxide (H2O2) solution and to explore the rheological properties of H2O2 activated CRM (ACRM) asphalt. Three different percentages of H2O2 solution were used to activate crumb rubber. The surface properties of oxidized rubber were analysed using scanning electron microscopy. Moreover, the pore structure in rubber powder was investigated. The rheological properties of bitumen samples obtained from treated and untreated rubber were characterized by conducting dynamic shear rheometer tests. The test results show that the average pore size of the crumb rubber after activation with H2O2 solution is significantly smaller than that of the inactivated crumb rubber, and the volume and surface area of the crumb rubber pores change with H2O2 solution activation in a certain pattern. With the increase in H2O2 solution content, the contact surface between the particles increases, the floccules and pores of the powder increase, and the interface degree between the crumb rubber powder and the asphalt is strengthened. Solubility of the rubber hydrocarbon and the release ability of the carbon black particles from the crumb rubber in the asphalt binder increase, but the mechanical properties of the crumb rubber, including the strength, elasticity, and wear resistance, decrease. As a result, a reduction is observed in the elasticity, viscosity, high-temperature rutting resistance, and elasticity of the ACRM asphalt.
Bo Li; Hao Li; Yongzheng Wei; Xingjun Zhang; Dingbang Wei; Jia Li. Microscopic Properties of Hydrogen Peroxide Activated Crumb Rubber and Its Influence on the Rheological Properties of Crumb Rubber Modified Asphalt. Materials 2019, 12, 1434 .
AMA StyleBo Li, Hao Li, Yongzheng Wei, Xingjun Zhang, Dingbang Wei, Jia Li. Microscopic Properties of Hydrogen Peroxide Activated Crumb Rubber and Its Influence on the Rheological Properties of Crumb Rubber Modified Asphalt. Materials. 2019; 12 (9):1434.
Chicago/Turabian StyleBo Li; Hao Li; Yongzheng Wei; Xingjun Zhang; Dingbang Wei; Jia Li. 2019. "Microscopic Properties of Hydrogen Peroxide Activated Crumb Rubber and Its Influence on the Rheological Properties of Crumb Rubber Modified Asphalt." Materials 12, no. 9: 1434.
Effective approaches are required to be developed to solve the poor compatibility and thermal stability problems of crumb rubber-modified asphalt (CRMA). This study focuses on a method called microwave activation. However, seldom researches pay attention to the properties of MACRMA after aging. The objective of this study was to prepare microwave-activated CRMA (MACRMA) and investigate the performance of asphalt after aging. The samples were subjected to thin-film oven test (TFOT) at different times and temperatures. The effect of heat aging on the properties of MACRMA was evaluated by three indicator tests: viscosity, dynamic shear rheology test (DSR), and repeat creep recovery test (RCRT). The test results indicated that the MACRMA after two aging conditions had noticeably lower performance values (e.g., penetration, ductility) compared to unaged samples, and thus, the need to control temperature and time for mixing and construction was verified to be important. In addition, the G*/sin δ and phase angle values were largely influenced by the TFOT aging temperature and time. The MACRMA’s ability to recover was improved after aging. Compared with the aging temperature, the aging time had a more significant effect on the deformation and recovery ability of MACRMA.
Bo Li; Jianing Zhou; Zhihao Zhang; Xiaolong Yang; Yu Wu. Effect of Short-Term Aging on Asphalt Modified Using Microwave Activation Crumb Rubber. Materials 2019, 12, 1039 .
AMA StyleBo Li, Jianing Zhou, Zhihao Zhang, Xiaolong Yang, Yu Wu. Effect of Short-Term Aging on Asphalt Modified Using Microwave Activation Crumb Rubber. Materials. 2019; 12 (7):1039.
Chicago/Turabian StyleBo Li; Jianing Zhou; Zhihao Zhang; Xiaolong Yang; Yu Wu. 2019. "Effect of Short-Term Aging on Asphalt Modified Using Microwave Activation Crumb Rubber." Materials 12, no. 7: 1039.
To thoroughly explore the relationship between concrete pavement texture characteristics and tire/pavement noise of grooving concrete pavement, the surface texture, i.e., roughness, macrotexture, and microtexture, was investigated in numerous highway pavements. The On-Board Sound Intensity (OBSI) method was used to test the pavement/tire noise. The statistical correlation between concrete pavement texture characteristics and tire/pavement noise was quantitatively described by two correlation analysis methods for highway concrete pavement: origin of linear regression and the Pearson two-sided test method. The results indicate that the effect of pavement roughness on tire/pavement noise is significant, while the noise level is minor for the flat pavement. The macro texture depth also has a marked impact on the tire/pavement noise. In addition, a large grooving depth of concrete pavement could cause a high tire/pavement noise level; however, there is no clear correlation between side-way force coefficient (SFC) and tire/pavement noise.
Dingbang Wei; Bo Li; Zhengwei Zhang; Feng Han; Xingjun Zhang; Man Zhang; Liangying Li; Qicai Wang. Influence of Surface Texture Characteristics on the Noise in Grooving Concrete Pavement. Applied Sciences 2018, 8, 2141 .
AMA StyleDingbang Wei, Bo Li, Zhengwei Zhang, Feng Han, Xingjun Zhang, Man Zhang, Liangying Li, Qicai Wang. Influence of Surface Texture Characteristics on the Noise in Grooving Concrete Pavement. Applied Sciences. 2018; 8 (11):2141.
Chicago/Turabian StyleDingbang Wei; Bo Li; Zhengwei Zhang; Feng Han; Xingjun Zhang; Man Zhang; Liangying Li; Qicai Wang. 2018. "Influence of Surface Texture Characteristics on the Noise in Grooving Concrete Pavement." Applied Sciences 8, no. 11: 2141.
The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal component analysis. The performance experiments including cone penetration, softening point, flow, resilience and tension at low temperature respectively were conducted by reference of ASTM D5329 for eight sealants and fillers often used in China. There by a principal component model was developed and weight of every index was calculated. The experimental results show that there are significantly different performances for sealants and fillers often used in China. Principal component analysis is an objective method that evaluates and selects the performance of sealants and fillers for cracks in asphalt concrete pavements.
Bo Li; Xiaoyu Ren; Yanbo Li; Weizhong Ma; Hanlian Li. Evaluation and selection of sealants and fillers using principal component analysis for cracks in asphalt concrete pavements. Journal of Wuhan University of Technology-Mater. Sci. Ed. 2017, 32, 408 -412.
AMA StyleBo Li, Xiaoyu Ren, Yanbo Li, Weizhong Ma, Hanlian Li. Evaluation and selection of sealants and fillers using principal component analysis for cracks in asphalt concrete pavements. Journal of Wuhan University of Technology-Mater. Sci. Ed.. 2017; 32 (2):408-412.
Chicago/Turabian StyleBo Li; Xiaoyu Ren; Yanbo Li; Weizhong Ma; Hanlian Li. 2017. "Evaluation and selection of sealants and fillers using principal component analysis for cracks in asphalt concrete pavements." Journal of Wuhan University of Technology-Mater. Sci. Ed. 32, no. 2: 408-412.
We investigated microstructure morphologies of three asphalts (SK, Karamay, and Esso) used in China using atomic force microscopy (AFM). The topography and phase contrast images were obtained. Topographic profile and three dimensional images were described. Roughnesses of microstructure were calculated. And the chemical compositions of asphalt were tested to explain the microstructural mechanism of the asphalt. The results show that the topography and phase image in atomic force microscopy are appropriate to evaluate the microstructure of the asphalt binder. There are significant differences in microstructural morphologies including bee-like structure, topographic profile, 3D image, and roughness for three asphalts in this study. There are three different phases in microstructure of asphalt binder. The oil source and chemical composition of asphalt, especially asphaltenes content have a great influence on the microstructure.
Bo Li; Jinyu Yang; Zhanquan Chen; Hailian Li. Microstructure morphologies of asphalt binders using atomic force microscopy. Journal of Wuhan University of Technology-Mater. Sci. Ed. 2016, 31, 1261 -1266.
AMA StyleBo Li, Jinyu Yang, Zhanquan Chen, Hailian Li. Microstructure morphologies of asphalt binders using atomic force microscopy. Journal of Wuhan University of Technology-Mater. Sci. Ed.. 2016; 31 (6):1261-1266.
Chicago/Turabian StyleBo Li; Jinyu Yang; Zhanquan Chen; Hailian Li. 2016. "Microstructure morphologies of asphalt binders using atomic force microscopy." Journal of Wuhan University of Technology-Mater. Sci. Ed. 31, no. 6: 1261-1266.