scholarly journals Viscoelastic Properties, Rutting Resistance, and Fatigue Resistance of Waste Wood-Based Biochar-Modified Asphalt

Coatings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 89
Author(s):  
Ran Zhang ◽  
Haoxiang Wang ◽  
Jie Ji ◽  
Hainian Wang

The purpose of this study is to explore the viscoelastic properties, rutting resistance, and fatigue resistance of waste wood-based biochar-modified asphalt. The biochar with 2%, 4%, and 8% mixing amounts and two kinds of particle size, 75–150 μm and <75 μm, were used as modifiers of petroleum asphalt. Meanwhile, in the control group, a graphite modifier with a particle size of 0–75 μm and mixing amount of 4% was used for comparison. Aged asphalts were obtained in the laboratory by the Rolling Thin Film Oven (RTFO) test and the Pressure Aging Vessel (PAV) test. The viscoelastic properties, rutting resistance, and fatigue resistance of biochar-modified asphalt were evaluated by phase angle, critical high temperature, and fatigue cracking index by the Dynamic Shear Rheometer (DSR) test. In addition, the micromorphology of biochar and graphite was compared and observed by using the scanning electron microscope (SEM). The results show that increasing the mixing amount of biochar gave a higher elastic property and significantly better rutting resistance of the modified asphalt at high temperature. Compared with graphite, the biochar has a rougher surface and more pores, which provides its higher specific surface area. Therefore, it is easier to bond with asphalt to form a skeleton network structure, then forming a more stable biochar–asphalt base structure. In this way, compared to graphite-modified asphalt, biochar-modified asphalt showed better resistance to rutting at high temperature, especially for the asphalt modified with biochar of small particle size. The critical high temperature T(G*/sinδ) of 4% Gd, 4% WD, and 4% Wd was 0.31 °C, 1.57 °C, and 2.92 °C higher than that of petroleum bitumen. In addition, the biochar asphalt modified with biochar of small particle size had significantly better fatigue cracking resistance than the asphalt modified with biochar of large particle size. The fatigue cracking indexes for 2% Wd, 4% Wd, and 8% Wd were 29.20%, 7.21%, and 37.19% lower by average than those for 2% WD, 4% WD, and 8% WD at 13–37 °C. Therefore, the waste wood biochar could be used as the modifier for petroleum asphalt. After the overall consideration, the biochar-modified asphalt with 2%–4% mixing amount and particle size less than 75 μm was recommended.

2014 ◽  
Vol 1015 ◽  
pp. 283-286 ◽  
Author(s):  
Zeng Ping Zhang ◽  
Xing Jiao Wu ◽  
Xiao Fen Nan ◽  
Meng Jia ◽  
Ji Cheng Han

In order to increase the life of bituminous pavement, quality of bitumen needs to be enhanced and modified. Different dosages of nano-organic montmorillonite (nano-OMMT) were used as modifier for base asphalt. The effect of the contents of nano-OMMT on high temperature performance of asphalt was investigated. Experimental results showed that with the increase of nano-OMMT of content, the high temperature performance of asphalt was gradually improved. And the high temperature sensitivity of asphalt is also enhanced. The nano-OMMT modified asphalt is expected to possess superior rutting resistance to the base asphalt.


PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0247390
Author(s):  
Xinli Gan ◽  
Wenli Zhang

The objective of this study is to verify the feasibility of using biochar made from crop straw as a bitumen additive to improve some properties of bitumen. The differences between crop straw biochar prepared in a laboratory and commercial charcoal were investigated through scanning electron microscopy and laser particle size analyses. Furthermore, biochar-modified asphalt was prepared using the high-speed shear method, and the penetration, softening point, ductility at 15°C, and apparent viscosity of the asphalt binder with 6% biochar were measured at 120, 135, 150, 160, and 175°C. It was found that both the crop straw biochar and the commercial charcoal consist mainly of C, O, Si, and K, but the C content of crop straw biochar is slightly higher than that of commercial charcoal. The particle size of biochar is smaller than that of commercial charcoal, while the specific surface area is larger. It was determined that the addition of crop straw biochar significantly improved the high-temperature performance of asphalt, and that biochar and commercial charcoal have a similar influence on the high temperature performance of asphalt.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Xinquan Xu ◽  
Guilin Lu ◽  
Jun Yang ◽  
Xinhai Liu

High-modulus asphalt concrete (HMAC) is considered as an effective paving material for addressing the increasing heavy traffic and rutting problems. Therefore, one high-modulus agent was used in this study to prepare high-modulus asphalt binder with different dosages. The objective of this study is to investigate the performance and modification mechanism of high-modulus asphalt. The effects of high-modulus agent on the viscoelastic properties of asphalt with different dosages were quantified via rheological tests as compared to base binder and styrene-butadiene-styrene- (SBS-) modified asphalt. Moreover, the modification mechanism of the high-modulus agent was examined using fluorescence microscopy and infrared spectrum test. Based on rutting and dynamic modulus tests, the differences of road performances between high-modulus modified asphalt mixture and SBS-modified asphalt mixture were compared. The results demonstrate that the high-modulus agent improves the high-temperature performance and viscoelastic properties of the matrix asphalt. When the dosage increases to 6.67%, the modification effect is better than that of the SBS-modified asphalt. Furthermore, the results of the rutting test show that the high-modulus modified asphalt mixture has better resistance to deformation than the SBS-modified asphalt mixture. The dynamic modulus test further demonstrates that the high-modulus modified asphalt mixture exhibits superior performance in high-temperature range. Fluorescence microscopy shows that the high-modulus agent particles can swell in the asphalt to form polymer links that improve the viscoelastic properties of the asphalt. Based on the results of the infrared spectrum test, it can be concluded that a high-modulus agent changes the asphalt matrix via physical blending modification.


2019 ◽  
Vol 4 (4) ◽  
pp. 67 ◽  
Author(s):  
S. Saeed Saliani ◽  
Alan Carter ◽  
Hassan Baaj ◽  
Pejoohan Tavassoti

Utilizing recycled asphalt pavements (RAP) in pavement construction is known as a sustainable approach with significant economic and environmental benefits. While studying the effect of high RAP contents on the performance of hot mix asphalt (HMA) mixes has been the focus of several research projects, limited work has been done on studying the effect of RAP fraction and particle size on the overall performance of high RAP mixes produced solely with either coarse or fine RAP particles. To this end, three mixes including a conventional control mix with no RAP, a fine RAP mix (FRM) made with 35% percent fine RAP, and a coarse RAP mix (CRM) prepared with 54% of coarse RAP were designed and investigated in this study. These mixes were evaluated with respect to their rutting resistance, fatigue cracking resistance, and low temperature cracking performance. The results indicate that although the CRM had a higher RAP content, it exhibited better or at least the same performance than the FRM. The thermal stress restrained specimen testing (TSRST) results showed that the control mix performed slightly better than the CRM, while the FRM performance was adversely affected with respect to the transition temperature midpoint and the maximum tensile stress temperature. Both of the RAP incorporated mixes exhibited better rutting resistance than the control mix. With regard to fatigue cracking, the CRM performed better than the FRM. It can be concluded that the RAP particle size has a considerable effect on its contribution to the total binder content, the aggregate skeleton of the mix, and ultimately the performance of the mix. In spite of the higher RAP content in the CRM versus FRM, the satisfactory performance observed for the CRM mix indicates a great potential in producing high RAP content mixes through optimizing the RAP particle size and content. The results also suggest that the black curve gradation assumption is not representative of the actual RAP particles contribution in a high RAP mix.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Luchuan Chen ◽  
Wenjun Gu ◽  
Xuanyu Zhang

Nanoparticles have been widely adopted to improve the high-temperature performance of asphalt binder. However, the influence of moisture on high-temperature performance is not clear. Hence, the water absorption performance of the nano-SiO2-modified asphalt concrete is investigated. Based on this, to further analyze the pavement performance of the nano-SiO2-modified asphalt concrete, the coupled effects of high-temperature, moisture content, and nanoparticles content on the rutting resistance of the nano-SiO2-modified asphalt concrete are tested and revealed in this study. Results show that temperature has the most significant influence on the water absorption performance of the nano-SiO2-modified asphalt concrete. The rutting resistance of the nano-SiO2-modified asphalt concrete decreases as temperature and moisture content increase, especially for the temperature. The dynamic stability at the same temperature condition decreases approximately linearly as moisture content increases. The effect of the nano-SiO2 content is the most nonobvious.


Author(s):  
Ovidijus Šernas ◽  
Donatas Čygas ◽  
Audrius Vaitkus ◽  
Vytautė Gumauskaitė

Rubber derived from grinding of recycled cars and trucks tyres may be successfully used as a bitumen modifier. Number of researches reported sufficient characteristics of rubber modified asphalt binders or modified asphalt mixes in terms of improved permanent deformation and fatigue cracking. The behavior of crumb rubber asphalt binders depends on several factors, such as modification method, rubber content and size, modification temperature, mixing speed and time applied during the digestion process. The aim of this study is to evaluate the effect of crumb rubber amount and type on modified bitumen low and high temperature properties. This paper presents results of unmodified bitumen, crumb rubber crumb rubber and polymer modified bitumen. Low and high temperature properties have been evaluated using bending beam rheometer and dynamic shear rheometer. Moreover, softening point and viscosity tests have been performed. The study results revealed that crumb rubber modified bitumen performed better than pure bitumen and similarly to polymer modified bitumen.


2013 ◽  
Vol 372 ◽  
pp. 314-317
Author(s):  
Phu Cuong Cao ◽  
Zhong Yin Guo ◽  
Yong Shun Yang ◽  
Zhi Chao Xue

Based on the theory of viscoelasticity, the Dynamic Shear Rheology test is used as study method. Study subjects are AH70 asphalt, SBS modified asphalt and MAC modified asphalt. Study objective is to analyze the effects of both high temperature and loading frequency on asphalt binder in asphalt mixture. Results from studies have revealed that: At high temperature and low loading frequency, the elasticity of asphalt binder decreases or low possibility of strain recovery, rutting resistance parameter decreases or the risk of rutting increases; At high temperature and high loading frequency, the viscosity of asphalt binder decreases or the strain speed of asphalt binder increases; At low temperature and high loading frequency, the fatigue resistance parameter increases, in other words there exists high fatigue cracking potential.


2020 ◽  
Vol 165 ◽  
pp. 04078
Author(s):  
Yongmei Guo ◽  
Yadong Jie

In order to investigate the effect of organic montmorillonite (OMMT) and its content on properties of high-viscosity modified asphalt, a series of laboratory tests were carried out through zero shear viscosity (ZSV) at 60 °C, rutting factor, ductility at 5 °C, and fatigue factor to analyze high-temperature, low-temperature and anti-fatigue properties of high-viscosity modified asphalt with different OMMT contents. The results show that OMMT/high-viscosity modifier (HVM) composite modification can improve obviously high-temperature performance and fatigue resistance of high-viscosity modified asphalt, but the best improvement effect can be achieved only when adding proper amount of OMMT. The addition of a small amount of OMMT has little effect on low-temperature performance of high-viscosity modified asphalt, but when the content of OMMT exceeds 4%, its low-temperature performance will decrease significantly. The addition of OMMT can improve the temperature sensitivity of high-viscosity modified asphalt’s high-temperature performance, but reduces the temperature sensitivity of its fatigue resistance.


2019 ◽  
Vol 21 (1) ◽  
pp. 36-42 ◽  
Author(s):  
Nyoman Suaryana ◽  
Tedi Santo Sofyan

Research on the utilization of natural rubber for Hot Mixture Asphalt as modifier has been widely carried out, and more intensively since 2016 due to the declining global natural rubber price. Further research conducted is the utilization of pre-vulcanized concentrated rubber latex and rubber compound added with antioxidants and treated through vulcanization process. This study experimentally evaluates the performance of Asphalt Concrete Wearing Course (ACWC) using natural rubber and synthetic polymer as modifier, compared to ACWC without modifier (only petroleum asphalt).  The results show that the rubberized asphalt has higher index penetration value as well as higher elasticity compared to petroleum asphalt penetration grade 60, but lower than synthetic polymer modified asphalt. Similarly, the level of performance of rubberized asphalt mixtures, particularly resilient modulus, water resistance, deformation, and fatigue cracking, is between that of petroleum asphalt and synthetic polymer modified asphalt


Alloy Digest ◽  
2003 ◽  
Vol 52 (8) ◽  

Abstract Haynes 625SQ alloy is a modification of Haynes 625 alloy (see Alloy Digest Ni-354, January 1988) with tighter controls on chemistry and a finer grain size for fatigue resistance up to 680 deg C (1250 deg F). This datasheet provides information on composition, physical properties, microstructure, elasticity, and tensile properties as well as fatigue. It also includes information on high temperature performance as well as heat treating. Filing Code: Ni-612. Producer or source: Haynes International Inc.


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