The addition effects of macro and nano clay on the performance of asphalt binder

The study was carried out to explore the addition effect of macro and organically modified nanoclay on the physical and mechanical properties of asphalt binders. Both macroclay and modified nanoclay were blended in an asphalt binder in various percentages (starting from 2% to 8%). The blended asphalt binders were characterized using kinematic viscosity (C.st), softening point (°C), and penetration and compared with anunmodified binder. The tensile strength of the asphalt binders was also tested as a function of clay types and content%. The results of the study indicated an increase in softening point; kinematics viscosity and decrease in binder penetration. The tensile strength of modified clay binders was enhanced at all percentages by a comparison with both macroclay and unmodified binders. The best improvements in the modified binders were obtained with 6% nanoclay.     

纳米CaCO3改性沥青与SBS改性沥青综合比较研究

选择纳米CaCO3和SBS为改性剂,研究其对基质沥青的改性作用。针对改性剂的特性确定了相应的制备工艺。通过针入度、软化点、延度、布氏粘度扣动态剪切流变试验及混合料试验评价了改性沥青的路用性能。结果表明纳米CaCO3改性沥青路用性能得到了显著改善。最后对三种典型掺量的改性沥青性价比进行了对比分析,认为纳米CaCO3改性沥青在低等级路面使用中具有较高的性价比。     

钢桥面铺装用浇注式沥青结合料的制备与试验研究

为制备出适用于钢桥面铺装用的浇注式沥青结合料，对不同种类的沥青按照不同掺配量与特立尼达湖沥青混合形成的浇注式沥青结合料进行了针入度、软化点和延度等指标的测试。试验结果表明，特立尼达湖沥青的掺配量会直接影响到浇注式沥青结合料的高温稳定性能和拉伸变形能力。特立尼达湖沥青掺配量一定时，SBS改性沥青对浇注式沥青结合料的拉伸变形能力有很好的贡献，而30号沥青对浇注式沥青的高温稳定性较其它两类沥青贡献要大。另外，对于SBS改性沥青与湖沥青按7：3比例混合后的浇注式沥青结合料，掺配2％RH或者l％Sasobit改性剂能有效降低浇注式沥青的施工温度，达到环保、低碳的施工目的。研究结果为钢桥面铺装浇注式沥青混合料组成研究提供了基础。     

Laboratory evaluation of the effect of bentonite on performance of bitumen and hot mix asphalt mixtures

In this research study, bentonite additive was used to modify original binder (60–70 penetration grade). The experimental program included use of five percentages of bentonite (10%, 15%, 20%, 25%, and 30%) by weight of bitumen. Physical properties of modified and unmodified bitumen were evaluated through penetration grade, softening point, ductility, and temperature susceptibility tests. The performance characteristics of mixtures were determined through indirect tensile strength, resilient modulus, and moisture susceptibility tests. The results demonstrate that addition of bentonite improves Marshall stability, tensile strength, and resilient modulus of mixtures, but led to decrease the resistance to moisture damage.     

Influence of nanosilica on moisture resistance of polymer modified bitumens

In this research, the effects of nanosilica and polymer on moisture resistance and other properties of hot mix asphalt have been investigated. The asphalt binder was modified using polyethylene and polypropylene polymers with varying percentages of nanosilica. The Marshall stability, flow, indirect tensile strength, stiffness modulus and resistance to moisture damages test tensile strength ratio (TSR) and retained Marshall stability (RMS) tests were conducted. The results show that application of nanosilica improves the stability, reduces optimum binder content, increases stiffness as well as strength characteristic of the asphalt mixtures. Moisture damage analysis of the modified mixtures shows a good enhancement due to addition of nanosilica particles.     

聚合物改性沥青性能评价方法综述

聚合物改性沥青不仅增加了基质沥青体系复杂性，而且改变了基质沥青的流变性。传统的沥青试验方法已经不能准确地评价改性沥青的性能。为此，SHRP开发出基于性能的改性沥青性能评价方法，如动态流变剪切、弯曲流变仪和直接拉伸试验等。同时，一些化学分析方法如凝胶渗透色谱、示差扫描量热和红外光谱等方法也应用于改性沥青的性能评价研究中。     

利用环氧化SBS改性镇海沥青的研究

采用环氧化SBS改性镇海沥青,研究了改性沥青的针入度、软化点、延度的变化规律,并探讨了环氧化SBS改性沥青的机理.实验结果表明,SBS牌号、ESBS改性剂的环氧基质量分数和加入量以及反应时间等条件郝影响改性沥青的三项指标.     

老化对沥青胶结料常规指标的影响

沥青胶结料的老化是影响沥青路面使用性能的一个重要因素，应用旋转薄膜烘箱(RTFOT)对沥青进行短期老化，然后再应用压力老化仪(PAV)对其残留物进行不同时间的老化。对经过不同程度老化的沥青．进行常规的三大指标试验和拈度试验，探讨老化对沥青胶结料常规指标的影响，建立了耦合老化效应的沥青胶结料拈温方程。     

沥青胶结料基本高温性能指标相关性研究

高温稳定性是沥青胶结料重要技术要求之一。针入度、软化点、60℃动力黏度和针入度指数是工程中最为常用的高温性能评价指标。为探究这些高温性能指标的区分度和关联性,对34种源于不同工程的沥青胶结料进行检测,基于聚类分析法和灰色关联分析法对试验数据进行分析。结果表明,60℃动力黏度指标相比针入度和软化点指标能够更有效地区分不同沥青胶结料的高温性能;70号基质沥青和高黏度改性沥青的60℃动力黏度与软化点关联度高,但SBS改性沥青60℃动力黏度与其他高温性能指标的关联度低;考虑到动力黏度能够客观表征流变特性,建议在实际工程中可将60℃动力黏度列为强制性指标。     

Aging Performance of SBS Modified Asphalt

Abstract

The penetration, softening point, and ductility of the aging basic asphalt and styrene-butadiene-styrene (SBS) modified asphalt were studied, and the thin film oven aging behavior of them was researched by using infrared spectrum. The experimental results showed that the softening point was increased, the penetration and ductility were decreased after basic asphalt thin film oven aging; the results of aging SBS modified asphalt thin film oven aging was similar too. The research of infrared spectrum indicated that absorbing–oxygen oxidation reaction was taking place when basic asphalt film was aging, carbonyl and sulfoxide groups were increased after SBS modified asphalt thin film oven had been aging. The aging extent of SBS modified asphalt was bigger than basic asphalt and the ability of bearing low temperature was better. SBS modified asphalt could have worse anti-aging performances than that of base asphalt.     

发育时间对SBS改性沥青稳定性能的影响

考察了不同发育时间对改性沥青稳定性能的影响。结果表明,发育时间的增加,有利于改善改性沥青的稳定性能;不同的基质沥青以及改性剂调制改性沥青达到稳定体系时所需发育时间不同;随着发育时间增加,改性沥青的针入度、软化点、延度等性能发生系列变化。     

Study on Aging Kinetics of Panjin Paving Asphalt

In this paper, the changes of n-pentane asphaltene content, penetration, softening point, and ductility of two Panjin paving asphalts have been studied during aging. Further, based on the change of n-pentane asphaltene content, a study on aging kinetics of asphalt has been conducted. Some correlative kinetic parameters were calculated, and the aging kinetic equation of asphalt was gained. The value calculated, depending on the equation, was in accordance with the experimental data. In addition, the relationship between the composition of the high grade paving asphalt and its aging resistant performances was revealed. It showed that the aging of high grade paving asphalt was a first order reaction. Moreover, the kinetic model was proved to be reliable by investigating the changes of penetration, softening point, and ductility of asphalt during aging.     

改性剂类型对废胶粉/SBS复合改性沥青性质的影响机理研究

以中油燃料油股份有限公司高富炼油厂生产的50号重交道路沥青为基质沥青,研究了不同化学结构的SBS和不同粒径胶粉对废胶粉/SBS复合改性沥青软化点、针入度、低温延度以及动力粘度的影响,研究表明：复合改性沥青的粘度明显比单一改性剂生产的改性沥青高,星型SBS对软化点和粘度的影响较大,合适粒径的胶粉对复合改性沥青性能的改善较大。     

新疆岩沥青改性沥青高温性能试验研究

测试了不同新疆岩沥青掺量的改性沥青针入度、软化点、复数模量、相位角等技术指标,分析了新疆岩沥青对基质沥青高温性能的影响。结果表明：随着新疆岩沥青掺量的增加,改性沥青的针入度减小、软化点提高、车辙因子变大,改性沥青的高温性能得到增强：新疆岩沥青可改善沥青结合料的粘弹性质,表现为复数剪切模量的增加和相位角的减小;根据Superpave沥青胶结料高温性能分级标准,研究了新疆岩沥青对高温等级的增强效果。     

Study on Aging Kinetics of Saudi Arabian Paving Asphalt

The changes of n-pentane asphaltene content, penetration, softening point, and ductility of two Saudi Arabian paving asphalts have been studied during aging. Further, aging kinetics of asphalt, based on the change of n-pentane asphaltene content, has been studied. Some correlative kinetic parameters were calculated and the aging kinetics equation of asphalt was gained. The value calculated depending on the equation was in accordance with the experimental data. And the relationship between the composition of the high grade paving asphalt and its aging resistant performances was revealed. It showed that the aging of high grade paving asphalt was a first-order reaction. AH-70 paving asphalt has the following characteristics: higher reaction active energy, less reaction velocity constant, lower aging velocity, and better aging resistance performance compared with AH-90 paving asphalt. The changes of penetration, softening point, and ductility of asphalt during aging further proved that the kinetic model is reliable.     

Reinforcement effect of fiber and deoiled asphalt on high viscosity rubber/SBS modified asphalt mortar

In this paper we investigate the reinforcement mechanism of high viscosity rubber/SBS modified asphalt mortar mixed with fiber （mineral, lignin or carbon fiber） and deoiled asphalt （DOA）. The softening point, penetration and viscosity tests were conducted to characterize the engineering properties of asphalt-fiber mortar. The microstructure of fiber was observed using scanning electron microscopy （SEM）, and the results indicated that fiber can effectively improve the toughness of asphalt matrix through forming a spatial network structure, and then adhesion and stabilization of asphalt binder. The cone penetration test was designed to study the rheological property of fiber modified asphalt. The results indicated that the reinforcement effect increased with fibers and DOA fraction increasing to a certain threshold, and the optimal fiber content was dependent on the fiber type and its length. Fiber content and filler-asphalt ratio had significant effects on the softening point, penetration, viscosity and cone penetration of asphalt mortar.     

道路沥青及SBS改性沥青的紫外老化研究

采用紫外辐射试验对道路沥青和SBS改性沥青进行加速老化试验研究.利用老化前后的软化点、针八度、延度和四组分变化。分析了道路沥青的紫外线老化机理。结果表明:随紫外线老化时间的延长,道路沥青和SBS改性沥青软化点呈上升趋势、针入度和延度呈降低变化趋势,其中又以延度变化最为明显。经紫外线老化后道路沥青和SBS改性沥青的四组分也有变化,其中沥青质略微上升、芳香分略微降低,而饱和分和胶质变化不大。     

水滑石/废橡胶粉复合改性沥青的制备及其性能研究

以克拉玛依90号沥青作为基质沥青、废橡胶粉和水滑石（LDHs）作为改性剂,制备了LDHs/废橡胶粉复合改性沥青,在废橡胶粉加入量不变的条件下,考察LDHs加入量对复合改性沥青的物理性能、抗紫外老化性能和流变性能的影响。结果表明：当废橡胶粉加入量（w）为15%时,随着LDHs的加入,复合改性沥青的软化点升高,针入度和延度有所下降,两种改性剂相互结合,使复合改性沥青的物理性能得到改善,并且满足国家聚合物改性沥青标准的要求,考虑到改性剂成本,选取LDHs加入量（w）为3%～4%;LDHs的加入使复合改性沥青的软化点增量减小,残留针入度比和延度保留率上升,表明LDHs可明显提高复合改性沥青的抗紫外老化性能;LDHs的加入可使复合改性沥青复数模量和车辙因子增加,相位角下降,说明LDHs可提高复合改性沥青的抗车辙性能。     

Rheological properties of Deurex – modified WMA binder containing SBS

Recently, warm mixture asphalt (WMA) technologies drawn much attention for their benefits to environment and workability. Deurex is novel type of warm mixture asphalt additive, which is extracted from sugar cane. The objective of this study is to experimentally investigate the effect of Deurex on SBS modified asphalt. The Deurex was blended into SBS modified asphalt at the dosages of 2%, 3% and 4%. Physical properties tests including penetration, soft point and ductility, dynamic shear rheometer (DSR), and bending beam rheometer (BBR) tests were carried out. The test results showed that the increase in Deurex additive could significantly reduce the viscosity of SBS modified asphalt, which indicates that the Deurex can serve as an effective type of warm mixture asphalt additive. In addition, the results showed that the addition of Deurex can enhance the high temperature properties while lower the low temperature performance of SBS modified asphalt. However, as long as the Deurex dosage is not higher than 3%, the low temperature grade of WMA binder keep the same as the control binder.     

克拉玛依SBS改性沥青的热稳定性

采用化学复合法对克拉玛依沥青进行SBS改性，并对其热稳定性进行了考察。结果表明，化学复合法改性的沥青由于SBS与沥青之间有交联反应，它们的相容性好，使SBS能均匀稳定地分散在沥青中，且SBS的粒度小，因此具有良好的物理稳定性。模拟储存试验中沥青的软化点、针入度和延度数据表明，改性沥青在高温下具有良好的化学稳定性，其高低温性能也得以改善。按美国SHRP评价，克拉玛依SBS改性沥青达到了PG76-34等级。