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采用室内试验分析了岩沥青和SBS掺量对Terminal Blend胶粉改性沥青(TB沥青)性能的影响;采用荧光显微镜及表面能测试仪研究了岩沥青和SBS对于溶胶沥青的增强作用及增强机理.结果表明:岩沥青与SBS在提高TB沥青高温性能的同时,可在一定程度上保留其低温性能中的突出特点;TB岩沥青(内掺20%(质量分数,下同)岩沥青+20%橡胶粉)的PG分级可达PG 76-28;车辙试验表明掺量为2.0%的SBS与TB岩沥青(内掺10%岩沥青+10%橡胶粉)复合后的SBS/TB岩沥青改性沥青高温性能高于SBS掺量为4.5%的SBS改性沥青(PG 76-22),从而有效降低了SBS掺量;表面能试验与TSR试验结果均表明TB沥青的黏附性能随着岩沥青与SBS掺量的增加呈现出先增后减趋势,岩沥青与SBS总体上提高了TB沥青的黏附性;荧光显微镜的观测结果进一步证实了SBS与TB沥青二次复合后的改性沥青内部均匀、稳定. 相似文献
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文中分析了胶粉掺量、SBS改性剂掺量及加热次数对SBS/橡胶粉改性沥青物理性能的影响。研究结果表明,复合橡胶沥青的软化点与SBS改性剂掺量呈现正相关关系,黏度和针入度指数与SBS改性剂掺量呈现先正相关后负相关;复合橡胶改性沥青的软化点、黏度和针入度指数均与橡胶粉掺量呈现正相关关系;当SBS改性剂掺量为5%及橡胶粉改性剂掺量为18%时,其所有的性能达到最佳;随着加热次数的增加,橡胶复合改性沥青的高温性能有所降低。 相似文献
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由纤维与高黏度改性沥青、矿粉形成的高黏度改性沥青胶浆是影响排水沥青混合料性能的关键因素。为明确纤维对排水沥青混合料高、低温性能的影响机理,测试了聚酯纤维和玄武岩纤维排水沥青混合料的动稳定度和低温破坏应变,并采用动态剪切流变试验、弯曲梁流变试验等方法,对比研究了2种纤维对高黏度改性沥青胶浆高、低温性能的影响。为确定2种纤维最佳掺量范围,测试了不同纤维掺量下排水沥青混合料飞散损失。结果表明:纤维增加了高黏度改性沥青胶浆黏稠度,增大了高黏度改性沥青胶浆车辙因子,提升了排水沥青混合料的高温稳定性;纤维对高黏度改性沥青胶浆低温性能影响不明显,排水沥青混合料低温抗开裂性能的改善主要为纤维增强了集料间的黏结性能;排水沥青混合料聚酯纤维最佳掺量为0.15%左右,玄武岩纤维掺量范围推荐为0.20%~0.40%。 相似文献
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采用低温延度试验与弯曲梁流变试验,通过数据回归分析,对溶解性胶粉改性沥青及其与苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)复合的改性沥青低温性能进行评价.结果表明:当用胶粉和SBS对沥青复合改性时,增大胶粉质量分数能有效提升沥青的低温塑性变形能力和低温流变性能,增大SBS质量分数能提升沥青的低温塑性变形能力,但高掺量SBS可能降低沥青低温流变性能;随着胶粉质量分数和SBS质量分数的增大,沥青低温性能提升幅度逐渐降低;当胶粉质量分数为10%且SBS质量分数为2%时,改性剂利用效率最高. 相似文献
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为较大幅度提高沥青高低温性能和疲劳寿命,向基质沥青中添加纳米石墨烯微片(GNPs)和橡胶粉外掺剂,通过高速剪切机制备石墨烯微片/橡胶粉复合改性沥青,利用针入度试验、软化点试验及延度试验,分析GNPs和橡胶粉的不同掺量对基质沥青改性的影响规律,通过系统的室内试验,确定GNPs/橡胶粉复合改性沥青的最佳复合掺量,改善沥青的高低温抗永久变形能力,提高道路使用寿命。研究结果表明:橡胶粉掺量为18%时,针入度呈下降趋势,GNPs掺量为0.05%时,针入度数值达到最低;GNPs掺量为0.05%时,软化点达到峰值;在橡胶粉掺量18%、GNPs掺量为0.03%~0.05%时,延度增长的幅度最大。因此,本试验得到的橡胶粉与GNPs最佳掺量分别为18%与0.05%,此时复合改性沥青性能达到最优。 相似文献
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为确定基于表面改性处理的纳米阻燃剂的最佳掺量,并了解阻燃剂对沥青流变性能和燃烧特性的影响,采用动态剪切流变仪和弯曲梁流变仪研究了阻燃剂不同掺量下阻燃沥青的动态剪切、低温弯曲等流变性能;基于烟密度试验和极限氧指数试验,探究了不同掺量下阻燃剂对沥青的阻燃特性和抑烟性能的影响;采用热同步分析仪分析了阻燃沥青的燃烧动力学特征。研究结果表明:随着阻燃剂掺量的增加,阻燃沥青的车辙因子不断增大,可以提高阻燃沥青的高温流变性能,3%~9%阻燃改性沥青与原样改性沥青疲劳性能相当,若阻燃剂掺量继续增加,则对阻燃沥青的疲劳性能有害,且掺加阻燃剂对沥青低温性能有不利影响;为达到阻燃目的,烟密度和氧指数试验结果表明阻燃剂最低掺量宜不少于沥青质量的12%,结合沥青流变性能和阻燃性能确定阻燃剂最佳掺量为15%;基于对阻燃沥青燃烧过程的分析,发现原样沥青的燃烧过程可分为3个阶段,而掺入阻燃剂的改性沥青的燃烧过程可分为4个阶段,阻燃剂的掺入使SBS改性沥青的失重量减少、热解峰增多、燃烧焓值降低、热解过程变得更加复杂,发挥了气相阻燃和凝聚相阻燃的作用。 相似文献
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以SK90号基质沥青及不同掺量胶粉和SBS改性剂制备复合改性沥青,对其软化点等常规指标及流变力学指标进行检测。研究表明,随胶粉和SBS改性剂掺量提高,复合改性沥青的软化点、旋转粘度及弹性恢复等指标呈显著增大趋势,而针入度则不断减小,延度则先增大后减小;胶粉和SBS改性剂均可改善复合改性沥青的高温性能,且当胶粉掺量相同时,其高温性能随SBS改性剂掺量的增大而增大;随胶粉和SBS改性剂掺量的增大,复合改性沥青的m值不断减小,s值呈不断增大趋势;在胶粉掺量相对较低时,SBS改性剂对复合改性沥青的改性效果更加显著,而当胶粉掺量过大时,SBS改性剂对复合改性沥青的改性效果则显著减小。 相似文献
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通过小梁弯曲蠕变试验(BBR)以及半圆弯拉试验(SCB),对不同TB胶粉掺量和苯乙烯丁二烯苯乙烯嵌段共聚物(SBS)掺量的TB胶粉复合SBS改性沥青及其混合料的低温性能进行研究,并对其低温性能指标进行相关性分析.结果表明:与基质沥青相比,TB胶粉改性沥青具有优异的低温性能,且随着TB胶粉掺量的增加,其低温PG分级温度下降,沥青低温应力变小,混合料低温抗裂性增强;TB胶粉复合3%SBS改性沥青及其混合料的低温性能高于基质沥青,且随着TB胶粉掺量的增加,其低温性能改善效果较为显著,但低于相应掺量的TB胶粉改性沥青;随着SBS掺量的增加,10%TB胶粉复合SBS改性沥青的低温性能变化不明显,混合料的低温抗裂性变差;TB胶粉改性沥青的低温PG分级可以很好地反映沥青及其混合料的低温性能,而TB胶粉复合SBS改性沥青不能通过单一的PG分级来评价其低温性能,需要结合其他指标共同评价. 相似文献
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Crumb rubber modified asphalt (CRMA) was prepared by matrix asphalt preblending process (MAPP) which uses matrix asphalt as swelling agent in this study. Effects of the proportion of preblending matrix asphalt and properties of crumb rubber on performance of CRMA have been investigated. Scanning electronic microscope (SEM) and fluorescence microscope were adopted to characterize the microstructures of crumb rubber powder and CRMA, respectively. The experimental results indicated that the CRMA have better performance compared with matrix asphalt; the properties of crumb rubber display significant effects on the performance of CRMA, performance of CRMA are improved with the decrease of ash content and the increase of acetone extract. SEM graphs of crumb rubber pre and post preblending demonstrated that the morphological characteristic of preblended crumb rubber powder is obviously different from rubber powder without preblending, and the properties of rubber elastomeric are recovered and improved significantly. Micrographs of CRMB prepared under different conditions showed that compared with CRMB prepared by the traditional preparation process, the scattering state of rubber powder and matrix asphalt in CRMB prepared by MAPP is excellent, even and perfect polymer reticular structure is formed in the sample system. 相似文献
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Peipei KONG Gang XU Xianhua CHEN Xiangdong SHI Jie ZHOU 《Frontiers of Structural and Civil Engineering》2021,15(6):1390-1399
High viscosity asphalt (HVA) has been a great success as a drainage pavement material. However, the larger porosity of drainage asphalt mixtures weakens the cohesion and adhesion and leads to premature rutting, water damage, spalling and cracking. The purpose of this study was to investigate the rheological properties of HVA prepared using different high viscosity modifiers through conventional tests, Brookfield viscosity tests, dynamic shear rheometer tests and bending beam rheometer tests. The conventional performance results demonstrated SBS + rubber asphalt (SRA-1/2) exhibited excellent elastic recovery and low-temperature flexibility. The 60°C dynamic viscosity results indicated TPS + rubber asphalt (TRA) had the excellent adhesion. The rotational viscosity results and rheological results indicated that SRA-2 not only exhibited excellent temperature stability and workability, as well as excellent resistance to deformation and rutting resistance, but also exhibited excellent low-temperature cracking resistance and relaxation performance. Based on rheological results, the PG classification of HVA was 16% rubber + asphalt for PG76-22, 20% rubber + asphalt for PG88-22, TRA and SRA-1/2 for PG88-28. From comprehensive evaluation of the viscosity, temperature stability and sensitivity, as well as high/low temperature performance of HVA, SRA-2 was found to be more suited to the requirements of drainage asphalt pavement materials. 相似文献
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基于灰色系统理论的橡胶粉改性沥青性能评价 总被引:1,自引:0,他引:1
采用灰色关联分析法探讨了橡胶粉与基质沥青的相容性以及改性沥青的性能。关联度的结果表明,对胶粉改性沥青改性效果起主要作用的是基质沥青的芳香分含量和沥青质含量。胶粉的掺量对改性沥青的针入度性能有较高的关联度。 相似文献
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Carl Thodesen Khaldoun Shatanawi Serji Amirkhanian 《Construction and Building Materials》2009,23(1):295-303
Asphalt binder viscosity is of great importance during the production process of hot mix asphalt mixture as typically asphalt plants will store binders between 149 °C and 177 °C. SHRP guidelines state that asphalt binder viscosity must not exceed 3 Pa s. Therefore, given the documented increases in asphalt viscosity when modified with crumb rubber modifier (CRM) it is necessary to produce asphalt binder that fulfills the SHRP criteria while not exceeding plant mixing and storing requirements. This paper reports the results of an investigation of the importance of CRM properties on viscosity of CRM binder. Two binder sources were modified at four concentration levels using four different crumb rubber sources; the viscosities of the produced binders were evaluated by AASHTO T 316. Crumb rubber properties were evaluated by elemental analysis using a scanning electron microscope (SEM) and by determination of glass transition temperature (Tg) using a differential scanning calorimeter (DSC). In general, results indicate that processing procedure and tire type plays an important role in the determination of CRM binder viscosity. 相似文献