浅谈SBS改性剂对沥青混合料性能的作用

就如何提高沥青混合料强度进行了探讨,从马歇尔稳定度、车辙及冻断等方面研究了SBS改性剂对沥青混合料性能的作用,通过理论分析和大量试验证明SBS型改性剂是一种综合改善沥青混合料性能的改性剂。     

Duroflex~改性剂对沥青混合料性能影响研究

介绍了Duroflex改性剂的作用机理,分析了改性剂在不同掺量下对沥青粘度及沥青混合料水稳定性、高温稳定性、抗疲劳性能的影响,理论上得出Duroflex改性剂在混合料中的合理掺量为0.4%;对比试验分析了掺Du-roflex改性剂沥青混合料与SBS改性沥青混合料的性能,结果表明AC-25C型混合料中掺0.3%的Duroflex改性剂与SBS改性沥青混合料的水稳定性相当,但SBS改性沥青的高温稳定性具有一定优势。     

基于疲劳性能的应力吸收层混合料设计指标

以基质沥青与胶粉搅拌制备橡胶沥青,以基质沥青与SBS改性剂搅拌制备SBS改性沥青,然后分别采用相应的级配设计橡胶沥青应力吸收层混合料和SBS改性沥青应力吸收层混合料.选取目前常见的Strata应力吸收层混合料为对比材料,通过大量四点弯曲小梁疲劳试验（15℃）对这3种改性沥青混合料进行1500×10-6应变下的疲劳试验,分析混合料疲劳寿命与胶粉掺量(质量分数)、SBS改性剂掺量(质量分数)及改性沥青针入度、软化点、黏度的关系.结果表明：Strata应力吸收层混合料在1500×10-6应变下的疲劳寿命为302023次,因此以1500×10-6应变下疲劳寿命≥3×106次作为应力吸收层混合料的设计指标.橡胶沥青应力吸收层混合料疲劳寿命与胶粉掺量和橡胶沥青177℃黏度具有很好的相关性,按设计指标进行橡胶沥青应力吸收层混合料设计时,要求胶粉掺量为19.6%～20.5%,橡胶沥青177℃黏度维持在3.4～3.6Pa·s.SBS改性沥青应力吸收层混合料疲劳寿命与SBS改性剂掺量和SBS改性沥青针入度、软化点、135℃黏度具有很好的线性相关性,按设计指标进行SBS改性沥青应力吸收层混合料设计时,若A型、B型SBS改性剂混合使用,则要求SBS改性剂掺量≥6.5%,SBS改性沥青针入度≤5.1mm,SBS改性沥青软化点≥93℃,SBS改性沥青135℃黏度≥1.95Pa·s;适当加大油石比和调整级配中关键筛孔通过率可增大SBS改性沥青应力吸收层混合料疲劳寿命;B型SBS改性剂更适合用在SBS改性沥青应力吸收层混合料设计中.     

LDHs/SBS改性沥青混合料性能的研究

采用不同LDHs改性剂掺量的LDHs/SBS改性沥青制备LDHs/SBS沥青混合料,通过一系列试验,研究了LDHs改性剂不同掺量对LDHs/SBS沥青混合料性能的影响。研究结果表明:沥青混合料的稳定性随LDHs掺量增加而提高并且体积性能指标不变;LDHs的加入能改善沥青混合料的水稳定性,但加入量超过5%时改善能力减弱;随着LDHs掺量的增加,沥青混合料的高温抗车辙性能提高。     

多聚磷酸复合改性沥青混合料的路用性能

采用重复蠕变恢复试验分析了多聚磷酸对基质沥青、SBS及SBR改性沥青抗变形恢复能力的影响,并通过贯入剪切试验、半圆弯拉试验及弯曲疲劳试验评价了多聚磷酸对基质沥青混合料、SBS改性沥青混合料及SBR改性沥青混合料抗剪切性能、低温抗裂性能及疲劳性能的影响,采用Weibull分布分析了不同沥青混合料在不同失效概率下的疲劳性能.结果表明:多聚磷酸的掺入显著增加了沥青的黏度,对其弹性变形恢复能力贡献较小,而SBS改性剂可大幅度提高沥青的弹性变形恢复能力;多聚磷酸能够明显改善沥青混合料的高温抗剪稳定性;通过复配SBS或SBR改性剂,可有效弥补多聚磷酸对沥青混合料低温性能的负面影响;多聚磷酸对沥青混合料的疲劳性能也有一定程度的改善.     

玄武岩纤维高模量沥青混合料疲劳性能试验研究

为探讨玄武岩纤维和高模量改性剂在提高沥青混合料抗疲劳性能方面的适用性,选取AC-20C级配,对比分析了基质沥青混合料、SBS改性沥青混合料、玄武岩纤维沥青混合料、高模量沥青混合料以及玄武岩纤维高模量沥青混合料在不同应变水平下的疲劳寿命次数。结果表明:玄武岩纤维和高模量改性剂对沥青混合料的疲劳性能改善明显。     

SBS改性剂对沥青混合料高温稳定性的影响

以AC-16混合料的3种级配为研究对象,通过室内车辙试验分析了3种级配在不同SBS改性剂掺量下的高温稳定性。分析结果表明:随着SBS改性剂掺量的增加,沥青混合料的动稳定度DS会明显增大,车辙深度RD会明显减小;较粗集料的沥青混合料的动稳定度明显高于较细集料沥青混合料的动稳定度。     

聚酯纤维改性沥青混合料的高温和水稳定性

基于车辙试验和浸水马歇尔试验,研究了聚酯纤维和SBS改性剂对沥青混合料高温稳定性和水稳定性的影响.结果表明:聚酯纤维适宜掺量为0.20%～0.25%(质量分数);采用聚酯纤维和SBS改性剂对沥青混合料进行综合改性,可使其路用性能更趋完善.     

高模量改性剂的作用机理及应用研究

以70#石油沥青、SBS改性沥青和高模量改性沥青为研究对象,通过流变试验,定量研究了高模量改性剂掺量对沥青黏弹特性的影响,并与SBS改性沥青进行了对比分析,结合荧光显微试验,研究了高模量改性剂的改性机理;基于车辙试验和动态模量试验,分析比较了高模量改性沥青混合料和SBS改性沥青混合料在路用性能方面的差异.结果表明:高模...     

不同改性乳化沥青及其冷拌冷铺混合料性能研究

采用先乳化后改性方法制备SBR、SBS、水性环氧树脂(WEP)、VAE四种改性乳化沥青,基于改性乳化沥青蒸发残留物针入度、5℃延度、软化点、黏韧性试验确定最佳改性剂掺量,基于室内试验对比分析不同改性乳化沥青及其混合料的性能。结果表明,掺加SBR、SBS、WEP、VAE四种改性剂均可以显著提高乳化沥青的高温性能和黏韧性,并能显著提高乳化沥青混合料的力学性能、路用性能、抗疲劳性能和高温长期稳定性。建议用于乳化沥青改性剂时,SBR、SBS、WEP、VAE四种改性剂用量以不超过5%为宜。     

改性沥青混合料高温流变特性初探

在不同温度和不同荷载水平下对基质沥青混合料和SBS改性沥青混合料进行了静、动载流变试验，在分析了大量试验数据的基础上，得到的试验结果验证了SBS对沥青路面高温性能的改善作用。     

SBS改性沥青混凝土在中修工程中的应用

结合某中修工程，介绍了改性剂的确定，阐述了SBS改性沥青的加工工艺和AG16Ⅰ型改性沥青混凝土的配合比设计，实践证明，SBS改性沥青对低温抗裂性有明显提高，还有待进一步研究。     

Thiopave改性沥青路面力学响应研究

基于Thiopave改性沥青路面良好的高低温稳定性,采用有限元软件对典型半刚性基层沥青面层进行计算,得到不同沥青面层层底力学响应,并对计算结果进行对比研究,得到的主要结论如下：Thiopave沥青路面层底弯拉应力显著大于SBS沥青及基质沥青路面,路表轮隙中心处弯沉值小于SBS沥青及基质沥青路面;随着SEAM掺量的增加,...     

Investigation of rutting performance of asphalt mixtures containing polymer modifiers

The purpose of this study is to evaluate mechanical properties of control and modified asphalt mixtures. Conventional and five modified asphalt mixtures were studied on hot mix asphalt permanent deformation resistance. Amorphous polyalphaolefin, cellulose fiber, polyolefin, bituminous cellulose fiber and styrene butadiene styrene were used as modifiers. Indirect tensile strength, indirect tensile, static and repeated creep and LCPC wheel tracking tests were used for different loading conditions and temperatures. Research was focused on comparing the interaction between LCPC wheel tracking and other mechanical tests. According to the LCPC wheel tracking and repeated creep test results SBS mixtures were found as the most resistance mixtures in view of the rutting. Additives performed different performance levels but showed more resistance to permanent deformation according to the conventional mixtures. As far as the static creep test results are concerned there are controversial results because conventional mixtures are better. It is thought that this result may stem from the static behavior of the load and rheological change of bitumen with modifiers.     

Rheological properties and storage stability of bitumen/SBS/montmorillonite composites

Styrene–Butadiene–Styrene triblock copolymer is commonly used for modifying physical, mechanical and rheological properties of bitumen. Because of the poor compatibility between SBS and bitumen, SBS modified bitumen is not storage stable at high temperature. To obtain more compatibility between SBS and bitumen, several methods have been suggested. In this study, organophilic montmorillonite/SBS modified bitumen mixtures were prepared by melt intercalated blending. Physical and rheological properties of polymer modified bitumen were compared before and after adding nanoclay to the bitumen. Results showed that the presence of nanoclay improves the storage stability of PMB significantly without adverse effect on other properties of it. The structure of OMMT/SBS/bitumen blend was characterized by XRD. The spectra indicated that proper dispersion of OMMT in SBS led to a homogenous blend which is named exfoliated structure. The result of storage stability test showed that the difference in softening point was in good accordance with ASTM standard limitation which means that OMMT can improve the storage stability of PMB. Also morphological analysis confirmed storage stability results.     

SBS改性沥青混合料的施工控制要点

从施工温度要求、施工前准备工作、混合料拌合质量控制、摊铺、压实、接缝处理等方面介绍了SBS改性沥青混合料的施工控制要点，以保证改性沥青路面的安全、高效运营。     

高模量沥青混合料施工技术

通过具体工程实例，介绍了高模量沥青混合料的配合比设计，提出了高模量沥青混合料的施工工艺流程，重点探讨了沥青混合料的运输、摊铺和碾压，积累了高模量沥青混合料施工经验。     

基于凝胶渗透色谱法的改性沥青中SBS降解行为研究

为了探明改性沥青中SBS(苯乙烯-丁二烯嵌段聚合物)在施工及使用过程中的老化行为,通过对改性沥青在RTFOT、PAV老化前后的凝胶色谱分析研究了SBS的降解过程.结果表明:改性沥青经历RTFOT老化后有少量SBS交联结构发生降解,对沥青仍具有较好的改性效果:改性沥青经历PAV老化后SBS发生严重降解,平均分子质量显著下降,部分SBS丧失对沥青的改性效果:线性和星型2种类型SBS的老化程度不同;荧光显微观测试验结果与GPC分析结论一致,证明GPC分析方法能有效表征SBS的降解过程.     

Durability of the adhesion between bituminous coatings and self-protection mineral granules of waterproofing membranes

Flat roofs in current buildings include a waterproofing system, often made of bituminous membranes with a self-protection constituted by mineral granules. These granules constitute the barrier against the fundamental environmental agent of degradation, the UV radiation. Therefore it is of paramount importance to understand the long-term performance of the self-protection layer, namely its adhesion to the coatings of bituminous membranes. This paper presents an experimental study on the behaviour of the self-protection granule of bituminous membranes when subjected to environmental agents of degradation. Different types of atactic polypropylene (APP) and styrene–butadiene–styrene (SBS) modified bituminous membranes, comprising different finishing systems, were exposed to the effects of elevated temperature and water for up to 24 weeks and 4 weeks, respectively. Following accelerated ageing, specimens of the different types of membranes were subjected to brushing tests, carried out according to EN 12039, in order to evaluate the adhesion of the self-protection granules. The results obtained in this study, which are compared with performance limits recommended by UEAtc directives, show that the higher loss of self-protection granule of bituminous membranes occurs in membranes modified by APP polymers. In addition, it was concluded that the effect of water is much more severe than that of elevated temperature.