Evaluation of Layered Inorganic Nano-powder Modified Bitumen

Thermal oxidative and aging as an inevitable process in the practical application of road asphalt has great effect on the properties of asphalt. In this paper,the influences of short-term thermal oxidative ageing and ultraviolet radiation(UV) aging on the dynamic viscosity,penetration,softening point and rheological properties of two kinds of layered inorganic nano-powder including organo-modified montmorillonite (OMMT) and nanometer brucite (Mg(OH)2) modified asphalts were studied respectively. The rheological properties of these binders have been determined using a dynamic shear rheometer (DSR) through temperatures sweep tests.The rheological and physical analysis showed the two major influences of ageing on the properties for two kinds of layered inorganic nano-powder modified bitumens. On one hand,ageing decreased the viscous behaviors of modified binders,on the other hand,ageing improved the elastic behaviors of modified binders. The performances of binders after aging depended on the combined effect between the modifier and the bitumen. Both the two modifiers resisted the aging of bitumens and the effect of OMMT was better.     

AH-90及PG70-28改性沥青老化性能研究

对AH-90基质沥青及PG70-28改性沥青分别进行了室内旋转薄膜烘箱老化、压力老化及室外光氧老化试验,采用针入度、针入度指数、延度、软化点等指标分析考察了室内热氧老化对沥青高温稳定性、低温开裂性及温度敏感性能的影响。结果表明:老化降低了沥青的低温抗裂性能,改善了沥青的抗高温变形性能和对温度的敏感性,改性沥青的抗老化性能明显优于基质沥青。采用粘温指数法、老化指数法分别考察了光氧老化及热氧老化沥青的感温性能和抗老化性能。结果表明,粘温指数法和针入度指数法具有较好的相关性,总辐射能为10.5 kJ/cm2的室外紫外光照射对沥青感温性能和路用性能的影响比PAV老化严重,在内蒙古强紫外线地区沥青路面设计时需充分考虑光老化带来的危害。     

Property of Anti-Ultraviolet Aging of LDHs Modified Asphalt

LDHs was introduced into 70# asphalt binder by different weight ratio. Asphalt penetration test, soft point test, ductility test, viscosity test, dynamic shear rheometer (DSR) test and Fourier transform infrared (FTIR) test, were conducted to characterize and predict the LDHs modified asphalt. Research results indicated that the LDHs has great effect on resistance to UV of asphalt, which makes the asphalt absorb less ultraviolet radiation under the same UV intensity. Complex modulus, phase angle and FTIR test results indicate that the LDHs can significantly enhance the property of anti-ultraviolet aging of asphalt. The test results show that the LDHs has an obvious improvement on the anti UV aging of asphalt.     

Road performances of mesoporous nano-silica modified asphalt binders

The objective of this paper was to find new modifier to improve the aging resistance and low temperature cracking resistance of asphalt. To investigate the aging resistance of modified asphalt binders, mesoporous nano-silica(doping Ti~(4+)) was used as a asphalt modifier. Some physical properties including penetration, ductility, and softening point of asphalt were analyzed with RTFO(Rotating thin film oven) aging and ultraviolet aging. Moreover, the performances of high and low temperature of modified asphalt binders with pressure aging were tested by dynamic shear rheometer(DSR) test and bending beam rheometer(BBR) test. These results showed that the penetration decreased, low temperature ductility, and softening point increased when adding mesoporous nano-silica to base asphalt. After ultraviolet radiation aging, the penetration loss and ductility loss of modified asphalt decreased than that of original asphalt, the increase of softening point was also significantly reduced than that of base asphalt. Furthermore, The test results of DSR and BBR showed that the G*sinδ and creep modulus‘s' of pressure aged asphalt decreased, but the creep rate ‘m' increased. It can be concluded that the aging resistance and cracking resistance of modified asphalt are improved by adding mesoporous nano-silica, especially the doping of Ti~(4+) could improve the aging resistance obviously.     

有机膨润土复配SBS改性沥青性能的研究

研究了有机蒙脱土(OMMT)复配SBS改性沥青的性能.结果表明:SBS改性沥青的改性剂在沥青是以球状分布于沥青中,OMMT复配SBS改性沥青中的改性剂呈微米球状和细条形状;OMMT改性沥青可以提高改性沥青的高温性能、针入度比和耐老化性能,但对低温性能没有改善.OMMT复配SBS改性沥青的高温性能较好,有较好的耐老化性能,同时储存稳定性能也有一定的改善.     

有机化蒙脱土改性沥青老化性能的研究

采用熔融共混法制备了有机化蒙脱土(OMMT)改性沥青,通过薄膜烘箱老化试验(TFOT)和压力老化(PAV)试验,研究了OMMT对改性沥青老化性能的影响。结果表明,OMMT可显著减小沥青TFOT和PAV老化后粘度的增大、软化点的升高和针入度的降低,有效改善沥青的短期老化和长期老化性能;OMMT对沥青耐老化性能的改善作用随其用量的增加而增大,但当OMMT用量超过3%时,其对沥青耐老化性能的提高已较小。     

Rheological properties of asphalt modified by supramolecular UV resistant material-LDHs

Dynamic rheological properties of asphalt modified by Supramolecular UV resistant material-layered double hydroxides(LDHs) was studied by means of the dynamic shear rheometer(DSR) test.Two typical base asphalts were chosen and modified by 2 different LDHs contents.DSR tests were performed on the original samples,samples after exposed to outdoor and samples after the artificial accelerated UV aging tests respectively to analyze the rheological properties.It is found that when the LDHs content is between 3wt% and 5wt% of asphalt weight,the high temperature performance and fatigue resistant property of the modified asphalt become better,the UV aging resistance properties are improved.     

有机化蒙脱土对SBS改性沥青热氧老化性能的影响

将有机化蒙脱土(OMMT)与SBS改性沥青熔融共混,制备了OMMT/SBS改性沥青。利用X-射线衍射(XRD)分析了OMMT/SBS改性沥青的微观结构。通过长期热氧老化实验研究了OMMT对SBS改性沥青热氧老化行为的影响。XRD分析表明,OMMT/SBS改性沥青形成了剥离型纳米复合结构。热氧老化试验结果显示,OMMT可显著减少SBS改性沥青软化点和粘度的增加,提高其残留延度比和残留针入度比,明显改善了SBS改性沥青耐热氧老化性能。     

沙中高等级道路沥青抗老化性能的研究

以软化点为参数建立了沥青一级老化动力学模型,为研究沥青抗老化性能提供了一种简便可行的分析方法。并用该动力学模型对用沙中减渣研制的符合Q/SHR003-98标准的AH-70和AH-90两种高等级道路沥青的抗老化性能进行了比较,求得了动力学参数,同时用正戊烷沥青质老化动力学模型和老化指数方法比较了两种沥青的抗老化性能。结果表明,以软化点为参数的动力学模型与用正戊烷沥青质为参数的老化动力学模型以及用老化指数方法分析的结果完全一致,以软化点为参数建立的沥青老化动力学模型,能够很好的描述沥青的老化速率。通过对两种道路沥青抗老化性能的比较,表明AH-90沥青的抗老化性能优于AH-70沥青。     

Effect of organo-montmorillonite on the morphology and aging properties of various bitumens

Effect of organo-montmorillonite (OMMT) on the morphology and aging properties of various bitumens was studied. The morphology of the binders was characterized by atomic force microscopy (AFM). The influence of OMMT on physical properties of the binders before and after long-term aging and ultraviolet (UV) aging was investigated. It was observed that the effect of OMMT on the morphology and aging properties of bitumens depended on the base bitumen. In one case, OMMT affected the dispersed phase in bitumen. In the other case, OMMT affected the bitumen matrix. In both cases, OMMT caused stiffening of the modified phase. Compared with modification of the dispersed phase, modification of the matrix phase showed an obvious improvement on the physical properties as well as the better UV aging properties of bitumens, which was opposite to the long-term aging result.     

有机化累托石改性沥青的制备及性能研究

采用熔融插层法制备了有机化累托石(OREC)改性沥青,利用X射线衍射(XRD)表征了OREC改性沥青的微观结构,研究了OREC用量对改性沥青物理性能和粘度的影响,并通过薄膜烘箱(TFOT)和压力老化(PAV)对基质沥青和改性沥青老化性能进行了比较。结果表明:OREC可与沥青熔融插层形成剥离型纳米复合结构;OREC与沥青熔融共混后,沥青的软化点和粘度均增大;与普通沥青相比,经TFOT和PAV老化后,OREC改性沥青的软化点增量和粘度增加率显著减小,表明OREC可有效改善沥青耐老化性能。     

高弹性沥青及其混合料性能的试验研究

对高弹性沥青与SBS改性沥青、70#沥青的性能进行对比检测,着重进行60℃动力粘度和动态剪切试验以评价沥青胶结料的高温性能,并以车辙因子G＊/sinδ评价三种沥青的抗永久变形能力。对采用这三种沥青的AC-20型混合科的高温稳定性、水稳性、低温抗裂性能进行对比试验研究。结果表明,高弹性沥青的动力粘度、车辙因子远高于其他沥青胶结料,能够大幅提高混合料的高温性能,而且对抗水损坏、抗开裂等其他路用性能也有一定改善。     

阻燃沥青的研制

选用辽河AH-70号高等级道路沥青作为基质沥青,采用添加阻燃剂的方法制得了阻燃沥青。通过氧指数和水平燃烧系统地考察了十溴联苯醚、三氧化二锑、硼酸锌和氢氧化镁阻燃剂对沥青的阻燃效果,它们之间的协同效应,以及沥青在氢氧化铝、复合抑烟剂作用下的抑烟性能。结果表明,十溴联苯醚、三氧化二锑、硼酸锌和氢氧化镁分别对沥青具有一定的阻燃作用,其中,十溴联苯醚在这4种阻燃剂中阻燃效果优于硼酸锌、氢氧化镁和三氧化二锑,但其发烟量明显比其它阻燃剂大,三氧化二锑与十溴联苯醚之间存在着良好的协同效应,氢氧化铝和复合抑烟剂不但对沥青具有一定阻燃作用而且还有良好的抑烟作用。当它们按一定比例存在于共混体系中时,阻燃抑烟效果最佳,共混物的氧指数达到36.5%,水平燃烧达到I级难燃,发烟量较少。     

Rheological properties of conductive asphalt binders containing graphite and carbon fiber before and after ageing

Modified asphalt binders were prepared by adding conductive materials, graphite and carbon fiber. The rotation thin film oven test (RTFOT) and pressure age vessel test (PAV) were conducted to simulate the binder aging in the field. Rheological properties of graphite and carbon fiber modified asphalt binder were investigated by the empirically rheological properties (penetration and softening point) and the dynamic shear rheometer (DSR) test. Results show that physical properties of asphalt binder change with conductive material mixed. DSR tests present that the values of complex modulus increase while phase angles decrease under a proper amount of graphite and carbon fiber. Rutting parameters point out that graphite can improve the rutting resistance of asphalts. Rheological parameters can be used to assess aging.     

煤直接液化残渣共混改性沥青的性能和微观结构

为了研究煤直接液化残渣(direct coal liquefaction residue,DCLR)与沥青共混改性后的宏观性能和微观结构,以SK-90沥青为基质沥青,分别加入不同掺量(与基质沥青质量比为5%、10%、15%和20%)的DCLR,利用SHRP PG、针入度分级体系、红外光谱仪和凝胶色谱仪分析DCLR与沥青共混改性后宏观性能和微观结构的变化规律.试验结果表明:DCLR的加入可以改善沥青的高温性能,但对沥青低温性能和疲劳性能有一定的不利影响.同时,从DCLR共混改性沥青的官能团和相对分子质量分布的变化可以判断DCLR对沥青的共混改性主要为物理改性.     

布敦岩沥青混合料路用性能研究

为了分析布敦岩沥青混合料的路用特性,分别对基质沥青混合料、不同掺量布敦岩沥青混合料和SBS改性沥青混合料进行路用性能对比试验研究。结果表明,布敦岩沥青可以显著改善沥青混合料的高温稳定性、水稳定性、低温抗裂性和抗疲劳性能。综合考虑性能变化规律以及经济因素,推荐布敦岩沥青的合理掺量为3.5%。     

基于流变学方法的沥青中高温性能及胶浆抗剪强度研究

为了探究不同改性剂对基质沥青各项性能指标的改性效果,选取三种不同的改性沥青,SBS改性沥青、TPE改性沥青和高黏高弹改性沥青,进行室内试验研究对比。通过改性沥青胶浆锥入度试验、PG高温分级试验、温度扫描试验和MSCR试验,从抗剪强度、中高温性能、抗永久变形及变形恢复等方面系统地评估三种改性沥青的路用效果。研究结果表明:改性沥青及胶浆的制备,需要将制备时间、剪切速率、温度等参数严格控制在合理的范围之内,保证材料满足要求;各种沥青胶浆抗剪强度与温度呈现良好的相关性,并且各个回归方程的相关系数R²非常高,TPE改性沥青胶浆有着较高的抗剪强度;三种改性沥青流变试验显示,TPE改性沥青的中高温抗变性能力和高温蠕变恢复能力最佳,高黏高弹改性沥青次之,SBS改性沥青低于前两种沥青。     

高粘度改性沥青的老化性能研究

分别采用TPS和SBS制备了高粘度改性沥青和普通SBS改性沥青。研究了两种改性沥青在旋转薄膜烘箱(RTFOT)、压力老化箱(PAV)和紫外光老化前后物理性能的变化。结果表明:TPS改性沥青的抗短期热氧老化和长期热氧老化性能优于SBS改性沥青,同时,TPS改性沥青具有良好的抗紫外光氧老化性能。     

两种道路沥青抗老化性能的比较

研究了鞍山半氧化道路沥青的老化过程 ,提出了 2种沥青的动力学模型。通过对老化后 2种道路沥青使用性能、粘度以及胶体不稳定指数的变化 ,比较了它们的抗老化性能的优劣 ,并对道路沥青的老化机理进行了分析。结果表明 ,所提出的动力学模型能够很好的描述 2种道路沥青的老化速率。由dx/dt(AH - 90 ) >dx/dt(AH- 70 )可以初步证明AH - 70的抗老化性能优于AH - 90。老化后 ,AH - 70的针入度、软化点变化率均小于AH - 90的相应指标 ,AH - 70的老化指数也小于AH - 90的老化指数 ,这些都证明了AH - 70的抗老化性能好于AH - 90的抗老化性能。随着沥青老化的进行 ,沥青各组分都向着更重的方向转化 ,沥青质含量增加 ,沥青胶体的原有平衡结构遭到破坏 ,导致沥青使用性能变差     

废橡胶粉对SBS改性沥青的老化性能影响研究

在SBS改性沥青中加入糠醛抽出油溶胀后的活化废橡胶粉制备SBS／胶粉复配改性沥青,并对其热老化前后的软化点、针入度、延度等性能进行测试,表明在SBS改性沥青中加入胶粉并不影响改性沥青的热老化性能,而且对改性沥青的耐热老化性能还有一定程度的提高．对几组复合改性沥青的紫外线老化试验也表明加入废橡胶粉能够提高改性沥青的抗紫外老化性能．