钻屑残渣制备沥青路面面层重金属释放特征研究

目的 为进一步拓宽油基岩屑脱油残渣资源化利用途径,采用脱油残渣、矿粉、碎石等为原料,进行脱油残渣制备沥青路面可行性研究。方法 采用JTG/T F40-2004《公路沥青路面施工技术规范》、GB/T 30810-2014《水泥胶砂中可浸出重金属的测定方法》和EA NEN 7375-2004《模制或整体式块状材料的浸出特性标准》方法,考查了剩余固相替代矿粉制备的沥青面层试块的产品质量,分析了沥青面层重金属有效释放量和释放特性。结果 当剩余固相掺加量不高于4.8%(质量分数)时,制备出的沥青路面面层试块各项性能指标均符合JTG/T F40-2004要求。沥青面层试块浸出液中11种重金属(砷、钡、钴、铜、铬、锰、钼、镍、铅、钒、锌)释放率均低于1%。沥青面层试块中各重金属释放机理具有差异,其中砷、铬的释放机理主要为溶解作用,钡、钴、锰、镍、铅的释放机理主要为表面冲刷,剩余重金属受到扩散作用控制,且各重金属释放速率呈现钡<钴<锌<锰<镍<铬<砷<铅<铜的规律。结论 油基岩屑脱油残渣可替代矿粉,用于制备沥青面层试块,制备的沥青面层试块重金属迁移污染地...     

不同标号沥青的流变性能

借助温度扫描、频率扫描、多重应力蠕变恢复等实验,对20号、30号、50号、70号沥青及其旋转薄膜烘箱老化后沥青的流变性能进行了评价。结果表明：随着温度升高,4种沥青老化前后复数剪切模量和车辙因子均降低,并且老化后的高于老化前;在60℃温度下,无论是在低频还是高频荷载作用下,标号越低,沥青耐剪切变形能力越强,耐车辙性越好,而应力敏感性降低;标号越低的沥青,G-R参数值越大,耐开裂性则降低。     

30号硬质道路沥青组成结构对使用性能影响的机理研究

30号硬质道路沥青对提高路面高温稳定性能有显著效果,为探索影响沥青质量的内在因素,以溶剂脱沥青工艺制备的阿曼30号沥青和沙中30号沥青为研究对象,研究组成结构对使用性能的影响机理。结果表明,两种30号沥青均满足GB/T 15180—2010的要求,相比沙中30号沥青,阿曼30号沥青具有较好的高低温性能、抗老化性能和感温性能。组成结构研究表明,沥青的使用性能与其组成结构有着重大关联,不仅与组成存在比例关系,同时也与其内部结构紧密相关。相对于沙中30号沥青,阿曼30号沥青中各组分相对分子质量分布较宽,同时平均相对分子质量较高,各组分之间f_A,H/C,R_A/R_N,H_(AU)C_A等结构参数的差异性较小,胶体稳定指标I_c较高,主要组分芳香分、胶质和沥青质具有较长的侧链。高胶体稳定系数、较宽的相对分子质量分布、较小的组分结构差异性和具有长侧链等特点有利于形成稳定的胶体结构,进而使30号沥青体现出良好的高低温性能和抗老化性能。     

Modifying asphalt emulsion with different types of polymers for surface treatment applications

Asphalt emulsion produced from local asphalt 60/70 (Suez Co.) was modified with different types of polymers such as epoxy resin, latex styrene butadiene styrene (SBS), poly vinyl acetate (PVA), and with a mixture of two or more types of above mentioned polymers to produce a modified asphalt emulsion with high performance. This paper describes the method and technique for preparing asphalt emulsion as well as the tests, and evaluates several aspects concerning the prepared emulsion such as performance of evaporation residues, fuel and acid resistance, rheological properties, and durability. The results obtained revealed that all the modified asphalt emulsions gave better performance as compared with unmodified emulsion. Asphalt emulsion modified with a mixture of epoxy resin, latex SBR, and PVA showed the best road performance in terms of fuel and acid resistance. It was observed that the weight loss for unmodified binder, residue after evaporation of water, after immersion in kerosene for 120 min is 90% of its initial weight, while the binder improved with a mixture of SBS latex, epoxy resin, and PVA showed a weight loss of ?16% and 9% of its initial weight. Also, the admixture gives high acid resistance (weight loss ～ 9%) after immersing in 5% HCl. The dynamic viscosity test showed that asphalt emulsion modified with a mixture of SBS latex, epoxy resin, and PVA has the highest viscosity value which is a promising indication about the validity of its use for pavement in different applications.     

Use of Fourier transform infrared spectroscopy to study ageing characteristics of asphalt binders

The present study aims at studying ageing characteristics of conventional bitumen, polymer modified bitumen (PMB) and warm mix asphalt (WMA) by using FTIR. Results of obtained FTIR spectrum were quantified by calculating different indices and finally based on these indices ageing index of the binders for short- and long-term ageing were calculated. Results showed ageing increased amount of complex and high molecular weight components of the binders. PMB was found to have greater ageing resistance than conventional asphalt binders. In case of WMA, results found to be inconclusive, requiring further investigation.     

发育时间对橡胶沥青性能的影响研究

制备了不同发育时间的胶粉改性沥青样品,并通过动态剪切流变仪（DSR）和弯曲梁流变仪（BBR）等对其进行分析。用得到的高温指标（黏度、软化点、车辙因子等）和低温指标（延度、蠕变劲度）分析发育时间对胶粉改性沥青性能的影响。结果表明：胶粉改性沥青样品的高温性能和低温性能均较好;但随发育时间的增加,高温性能和低温性能有所下降,温度敏感性变大,胶粉和沥青的相容性变好,热储存稳定性变好。     

The characteristics of hot mixed asphalt modified by nanosilica

The objective of this research is to investigate the characteristics of the hot mixed asphalt modified by 2%, 4%, 6%, and 8% nanosilica by weight of binder. Marshall stability, dynamic creep, and indirect tensile tests were used to study effects of nanosilica on performance characteristics of the mixtures. Results showed that nanosilica can improve Marshall stability, resilient modulus, indirect tensile strength, and fatigue life compared to unmodified mixtures. However, the tensile strength ratio parameter in the moisture sensitivity tests indicated a decrease in the resistance of the modified mixtures against moisture damage.     

Preparation and evaluation of 30# hard grade asphalt

The preparation and evaluation of 30# hard grade asphalt by blending softening point hard deoil asphalt with several soft components were investigated. The results showed that the properties and proportions of blending soft components had a great influence on the properties of 30# asphalt. Chunfeng 70# asphalt and Maoming deoil asphalt were more suitable as blending soft components and their blended asphalt met the technical requirements of GB/T 15180-2010 when the proportion of hard deoil asphalt were 6–12% and 8–16%, respectively. PG grade results indicated that dynamic modulus of 30# asphalts at high temperature increased significantly, and antirutting ability was also improved notably, while the bending resistant ability at low temperature was slightly inferior to the high-grade asphalt. The results of mix performance tests showed that 30# hard grade asphalt had excellent anti–high-temperature deformation ability and preferable water stability compared with high-grade asphalts.     

Moisture susceptibility of warm mixed-reclaimed asphalt pavement containing Sasobit and Zycotherm additives

In this research, the influence of Sasobit and Zycotherm on the properties of reclaimed asphalt pavement (RAP)-warm mix asphalt (WMA) was investigated. Moisture susceptibility was evaluated applying the resilient modulus ratio, the indirect tensile strength ratio, and the fracture energy ratio. Laboratory testing results indicated that Zycotherm mixtures had more resistance to moisture damage than Sasobit WMA and hot mix asphalt (HMA) mixtures. The stiffness of mixtures increased dramatically by increasing the amount of RAP and using Sasobit exacerbated this problem.     

新型冷拌冷铺沥青混合料路用性能研究

为了提高普通乳化沥青混合料的路用性能,将乳化沥青与水性环氧树脂有机结合,得到一种新型复合材料——水性环氧乳化沥青。通过试验研究水性环氧树脂用量对混合料的力学强度、水稳定性以及温度稳定性的影响。结果表明：混合料的初期强度、后期强度以及高温稳定性随着水性环氧树脂用量的增加而提高,但其水稳定性和低温稳定性随着水性环氧树脂用量的增加先增大后减小,分别在水性环氧树脂用量为10%和15%时达到最佳提升效果。在实际工程应用中将水性环氧树脂用量控制在10%~15%之间。