废旧橡胶粉改性沥青在高速公路上的应用分析

随着我国经济的发展,废旧轮胎产生量也急剧增大,如何处理好废旧橡胶,对于充分利用再生能源减少环境污染有着非常重要的意义。介绍了废旧橡胶粉改性沥青的优良技术性能,分析比较了橡胶粉的加工工艺及其化学性能,重点阐述了橡胶沥青混合料设计方法及标准。结果表明：废旧橡胶粉改性沥青具有良好的路用性能,在环境保护方面也具有重大意义,是一种值得推广的沥青路面材料。     

废旧橡胶粉改性沥青混凝土的试验

利用废旧橡胶粉对道路沥青进行改性，可解决废旧橡胶粉的处理问题，有利于环保。探讨了废旧橡胶粉改性沥青AR-ACl3混凝土性能的高温抗车辙性能、抗低温和水稳定等路用性能。试验结果表明：废旧橡胶粉改性沥青AR-ACl3的混凝土具有良好的路用性能，是一种值得推广的沥青路面材料。     

橡胶改性沥青路面的研究与推广

利用废旧橡胶粉改善沥青路面技术性能的研究是江西省公路局和同济大学合作进行的,于1982年通过技术鉴定。至1988年共铺设一百多公里橡胶改性沥青路面,其耐磨、抗滑、防渗、抗裂性能明显提高,沥青的粘度、内聚力、延度及抗老化性大为改善。其特点是:(1)提高沥青热稳定性,(2)改善沥青低温塑性,(3)增强粘附性,(4)延长     

废胶粉粒径和掺量对多孔沥青混合料的性能影响研究

废旧轮胎用于沥青路面改性具有广阔的市场,多孔沥青混合料因其空隙率大而抗滑、降噪性能优异。分析了橡胶粉粒径分布及掺量对多孔沥青混合料性能的影响,采用3种粒径分布、3种掺量的胶粉进行干法改性,试验对比分析表明:掺#20～#200胶粉使得多孔沥青混合料试样渗透系数减小,飞散损失增大;一般情况下,胶粉粒径和掺量增加,多孔沥青混合料性能下降。     

橡塑复合改性沥青性质影响因素研究

废旧橡胶粉和废旧塑料对环境的污染日益严重,如果能变废为宝,既能有效解决环境污染问题又能促进橡胶、塑料工业的发展。研究发现,橡胶在一定程度能改善沥青的低温性能,塑料恰恰相反,能改善沥青的高温性能。研究利用废旧橡胶粉和废旧塑料为改性剂,对克拉玛依沥青进行复合改性,以期能制备出同时兼备两种改性剂优点的橡塑复合改性沥青,大幅度改善沥青的综合性能。     

橡胶粉掺量和目数对橡胶沥青粘度的影响机理研究

通过试验研究,基于沥青胶体结构理论,将橡胶沥青看做分散相（溶胀橡胶粉）分散在分散介质（沥青）中的胶体,分析了橡胶粉目数和掺量对橡胶沥青粘度的影响机理,认为：在橡胶粉掺量达到一定量后,掺量和目数对橡胶沥青中的分散介质粘度提高不再显著,主要通过显著提高分散相的体积数来增加橡胶沥青的粘度。     

SBS复合改性橡胶沥青试验研究

为了研究废旧橡胶粉和SBS复合改性沥青的结果,分析了聚合物改性沥青的改性机理,采用20%外掺橡胶粉,分别添加0.5%、1%、1.5%、2%的SBS进行复合改性,测试比较了复合改性橡胶沥青和普通橡胶改性沥青的主要指标,并研究了SBS掺量对橡胶沥青的影响,结果表明,复合改性橡胶沥青能达到比普通橡胶沥青更好的高低温性能。     

橡胶沥青路面首次应用在连云港市

由废旧轮胎和沥青为原料的橡胶沥青路面，近日在连盐高速公路起点连云港市灌云县境内段3．6km之内的路面上摊铺成功，这是橡胶沥青路面首次应用在连云港市的公路建设中。利用废旧轮胎生产的橡胶改性沥青铺设公路，除节约投资外，还可解决大量废旧轮胎产生的环保问题。     

不同改性沥青的OGFC混合料性能试验研究

对SBS—OGFC、干法RA—OGFC和湿法RA—OGFC三种混合料进行室内路用性能及耐久性试验。结果表明：掺加0．3％木质素纤维,SBS改性沥青和湿法生产的橡胶沥青OGFC混合料均表现出较好的路用性能和耐久性;干法生产的RA—OGFC橡胶沥青混合料部分性能达不到现行规范要求,性能较差。     

新型反应型活性橡胶沥青SHRP性能研究

活性橡胶是一种新型沥青改性材料,能有效消耗废旧橡胶和磷矿工业废弃物。道路沥青评价的常规指标并不能反映沥青随荷载、时间和温度变化时的流变学性质,而沥青的流变性直接影响沥青路面的使用性能。采用SHRP胶结料试验体系,选择应用较为广泛的70~#基质沥青、SBS改性沥青胶结料,对掺加活性橡胶前后的沥青胶结料性能进行对比研究。研究结果表明,活性橡胶改性技术可以提高70~#基质沥青与SBS改性沥青的高温性能、抗疲劳性能和低温性能,且对基质沥青的改善效果更加明显,但对沥青的施工和易性不利。     

废橡胶粉改性沥青配方与工艺条件研究

以辽河AH-70沥青为基质,废胶粉为改性剂,糠醛抽出油为助剂,合成出了各项性能达到美国废旧轮胎胶粉改性沥青标准FHWA-SA-92-002的改性沥青。研究了工艺条件及胶粉用量对改性沥青性能的影响。改性后,沥青的高温稳定性、低温抗疲劳性能和抗裂性能均获得明显改善。最佳工艺条件：混合温度170-180℃,剪切速率7000r／min,剪切时间30min。改性沥青配方(质量份)：基质沥青100;活化胶粉10-20;糠醛抽出油适量。     

加工工艺条件对胶粉改性沥青性质的影响

用废汽车轮胎粉生产改性沥青不但可以提高沥青的使用性能。还可以解决其"黑色污染"问题。以欢喜岭沥青为原料,采用湿法生产胶粉改性沥青过程中,剪切温度、剪切速率、剪切时间和胶粉加入量等都会影响胶粉改性沥青的性质。     

VISCOSITY OF BITUMEN-CRUMB RUBBER BLEND (NEW PAVING MATERIAL)

The feasibility of blending scrap tire rubber with Asphalt Ridge and Circle Cliffs (Utah, USA) tar sand bitumens was studied. Viscosity of the blended mixtures was analyzed as a function of composition, and coprocessing variables including processing temperature and time. Coprocessing of tar sand bitumens with crumb rubber at elevated temperatures has been shown to increase the viscosity of the bitumens with the exception of the bitumen-rubber sample prepared at 380°C. Optimum viscosity behavior was exhibited for an oil-extended bitumen blended with crumb rubber at 200°C for 0.5 hours. The viscosity of the bitumen-rubber blend prepared under these conditions met ASTM specifications of a viscosity-graded AC-30 asphalt binder. Viscosity increase was most noticeable at low temperature, providing the benefit of high viscosity at pavement temperatures experienced during summer months without concession of processability at pavement construction temperatures. A difference in viscosity was observed between bitumen modified with whole-tire crumb and tread-rubber crumb, due to the compositional differences that exist between the two materials.     

天然橡胶在芳烃油中溶胀和溶解过程的考察

Aromatic oil has been used to promote the properties of crumb rubber modified asphalt which is an ideal method to deal with the resource utilization of waste tire rubber and by-product of refinery. Furfural extract oil (FEO) was separated into light fraction and heavy fraction. Swelling and dissolution process of nature rubber sheet in these three oils was investigated to deal with the interaction mechanism. Crumb rubber was also interacted with FEO and asphalt respectively. Energy dispersive spectrometer (EDS), thermo-gravimetric analysis (TGA) and scanning electron microscope (SEM) were used to characterize the chemical and structural properties of processed rubber. Chemical composition of processed oils and asphalt was investigated by using four groups analysis (SARA) and gel permeation chromatography. The results reveal that swelling rate and mass loss of rubber in oils were much higher than those in asphalt and rose with increasing process temperature. Heavy fraction of FEO had more diffusion and dissolving capacity than light fraction, whilst compatibility was observed between heavy fraction with light fraction. Selectivity absorption was not observed in the study and detachment of dissolved rubber happened from outside to inside. The cross-linking degree of the residue rubber kept unchanged with process time, and sulfur preferred to remain in the undissolved rubber. Dissolution of crumb rubber in oils was attributed to devulcanization, and that in asphalt mainly belonged to depolymerization.     

VISCOSITY OF BITUMEN-CRUMB RUBBER BLEND (NEW PAVING MATERIAL)

ABSTRACT

The feasibility of blending scrap tire rubber with Asphalt Ridge and Circle Cliffs (Utah, USA) tar sand bitumens was studied. Viscosity of the blended mixtures was analyzed as a function of composition, and coprocessing variables including processing temperature and time. Coprocessing of tar sand bitumens with crumb rubber at elevated temperatures has been shown to increase the viscosity of the bitumens with the exception of the bitumen-rubber sample prepared at 380°C. Optimum viscosity behavior was exhibited for an oil-extended bitumen blended with crumb rubber at 200°C for 0.5 hours. The viscosity of the bitumen-rubber blend prepared under these conditions met ASTM specifications of a viscosity-graded AC-30 asphalt binder. Viscosity increase was most noticeable at low temperature, providing the benefit of high viscosity at pavement temperatures experienced during summer months without concession of processability at pavement construction temperatures. A difference in viscosity was observed between bitumen modified with whole-tire crumb and tread-rubber crumb, due to the compositional differences that exist between the two materials.     

DMA法研究不同粒径胶粉改性沥青黏弹性能

采用动态力学分析(DMA)方法,在动态剪切流变仪(DSR)上进行频率扫描实验,并利用广义Maxwell模型对实验结果进行拟合,得到胶粉改性沥青的离散松弛时间谱和零剪切黏度,并分析了胶粉粒径对胶粉改性沥青黏弹性能的影响。结果表明,在测定频率范围内,同一温度下改性沥青的损失模量(G″)大于储存模量(G′),且低频范围内两者差值较大;温度升高,G″和G′差别变大。在测定粒径范围内,G′和G″随胶粉粒径增加而增大,但粒径变化对胶粉改性沥青常规指标的影响较小。频率扫描结果与广义Maxwell 模型拟合结果一致,计算出的零剪切黏度(η0)随胶粉粒径的增加而增加。胶粉以条状或棒状结构分散在沥青中,胶粉粒径减小,条状结构变小且分散越密集。     

胶粉改性沥青混合料沥青用量检测试验的研究

采用离心抽提与燃烧两种方法,分别对不同石料、不同级配的干拌法、湿拌法胶粉改性沥青混合料进行沥青用量测定,并对比普通沥青混合料的试验结果。通过试验测定沥青用量与设定用量的对比,分析了两种测定方法的影响因素、胶粉对于沥青含量测定结果的影响及干、湿拌法的主要区别,研究结论对胶粉改性沥青大规模应用具有有益参考价值。     

道路沥青零剪切粘度与毛细管粘度的比较研究

粘度是评价道路沥青粘结特性的重要技术指标,也是条件性指标,不同测试方法得出粘度指标差异极大。基于沥青在路面结构中受力状态,对基质沥青、SBS、高强度、高粘度改性沥青等12种道路沥青60℃零剪切粘度、毛细管粘度进行比较研究,并对零剪切粘度测试方法进行简化。试验与分析表明：高粘度改性沥青在第一牛顿区共同区域范围内与沥青在路面结构中所受的剪切速率水平一致,零剪切粘度可以较为合理地表征沥青在路面结构中的粘结特性;高粘度改性沥青毛细管粘度存在虚高现象,无法有效表征高粘度沥青路用粘度特性,而基质沥青毛细管粘度对应的剪切速率在第一牛顿区域范围内,可作为零剪切粘度的替代指标,对基质沥青粘度性能进行评价。此外,建议利用剪切速率扫描试验进行零剪切粘度测试,取10-3～10-2s-1范围内测量粘度均值为零剪切粘度。     

橡胶与沥青的相互作用：溶胀及交联网络演化

橡胶与沥青的相互作用过程与结果决定了橡胶沥青的性能。用典型载重轮胎橡胶和轿车轮胎橡胶放入沥青中,研究其与沥青相互作用后橡胶溶胀质量变化规律及交联网络演化过程,结果表明：橡胶溶胀质量增量（MI）与2 t/（1/2）/d呈线型关系,而橡胶溶胀扩散系数（D）受溶胀温度、橡胶种类的影响。190℃下,1 mm厚载重车胎橡胶的网络结构在溶胀过程中不断破坏,并在24 h后出现橡胶的解体和脱落,而轿车轮胎橡胶网络结构比较稳定。热分析发现沥青与橡胶之间的相互作用限制了橡胶分子链的运动,使得玻璃化转变温度（T_g）升高,并有沥青中的结晶蜡进入橡胶内部;热重分析（TGA）表明溶胀后橡胶起始分解温度升高,相互作用使天然橡胶（NR）的热分解速率峰消失,而丁苯橡胶（SBR）的分解峰增强。