Shear resistance properties of TPS modified bitumen binders and asphalt mixtures

Shear resistance properties of the virgin bitumen and modified bitumen binders with Tafpack Super(TPS) modifier and SBS modified bitumen were discussed.Dynamic shear rheometer(DSR) was used to measure the laboratory creep data for these binders over a wide range of constant shear stresses at 20 ℃ to characterize the shear creep behaviors of all kinds of asphalt binders,and the rutting test system was used to investigate the permanent deformation of porous asphalt mixtures using the above bitumen binders for a fixed compressive stress.The shear strain rate and shear creep modulus were used to characterize the shear creep behavior of the TPS modified bitumen,and the rutting test results were used to show the consistency of porous asphalt mixtures with the bitumen binders.Results indicate that a distinction of shear creep strain can be made among different contents of TPS modified bitumen at the same stress level,where the shear creep strain-time response curve of the SBS modified bitumen binder is between the curves of the 8% TPS and 12% TPS modified bitumen binders.The shear strain rate and the shear creep modulus of the TPS modified bitumen binders are obtained to compare with those of the SBS modified bitumen binder which results in the same trend as the shear creep strain-time response curve.Permanent deformation results of all the porous asphalt mixtures from the rutting test show reasonable agreement with the findings of the shear strain rates and shear creep modulus over the range of shear stress levels.     

可抑制双模杂波的开环自适应动目标显示器设计

提出了一种可抑制双模杂波的开环自适应动目标显示器,并进行了理论分析和模拟计算,最后给出了电路实现方法。     

催化氧化法制取优质氧化沥青的研究

一、前言采用催化氧化法制取优质氧化沥青在国外已有多年的历史,优点是:(1)沥青的氧化反应速度显著提高;(2)沥青产品的软化点高,感温性能优良,而且弹性大。目前使用的催化剂有氧化物、金属粉末、硫化物、金属盐类以及制造合成润滑油的催化剂残渣等,其中以 FeCl_3和 P_2O_5效果尤佳     

基于独立分量分析的雷达网抗同频干扰仿真

研究雷达间的消除同频干扰问题,针对机载、舰载雷达网抗同频干扰是军事领域的目标探测正确性的要求,为了消除雷达同频干扰,根据同频干扰的特点,提出一种独立分量分析的抗干扰算法,应用于机载、舰载雷达网抗同频干扰处理过程中.通过从观测信号中将目标回波信号和同频干扰信号分离出来,提取目标回波信号,从而自适应地抑制同频干扰信号,达到抗同频干扰的目的.仿真结果表明,采用上述方法分离目标回波信号和同频干扰信号取得了较好的效果,证明其应用在雷达网抗同频干扰处理中是可行和有效的.     

复合型混凝土养护剂的研制

采用石蜡乳液、硅酸盐溶液及复合乳化剂等为原材料，利用均匀设计和调优软件对新型混凝土养护剂配方进行设计，合成复合养护剂。对养护剂的养护效果，如保水率、强度提高率及耐磨性改善等进行了测试和分析。结果表明，复合养护剂不仅有较好的保水率，同时经其养护的混凝土的强度和耐磨性均有明显的提高或改善。     

高寒地区水泥混凝土桥面沥青铺装层抗疲劳开裂性能分析

混凝土桥面沥青铺装层在使用期间产生的疲劳开裂是世界各地桥面铺装常见的问题,该文依托内蒙古教来河大桥采用有限元分析软件ANSYS对于高寒地区混凝土桥面沥青铺装层的疲劳开裂性能进行分析研究。分析提出高寒地区混凝土桥面沥青铺装层深度0~2 cm区域可作为铺装层内部常温拉应力的峰值分布区域;铺装层内的常温拉应力均随着上面层/下面层厚度的增加而减小;通过增加高寒地区混凝土桥面沥青铺装层的厚度来改善桥面铺装层的抗疲劳性能。     

Influence of conductive additive on temperature susceptibility of asphalt binders

The effects of graphite on temperature susceptibility of asphalt binders were investigated by penetration test,Ring & Ball softening point test and viscosity test.And penetration index(IP),viscosity-temperature susceptibility(SVT),and penetration-viscosity numbers(NPV) were introduced to evaluate the effects.The results show that the penetration,softening point and viscosity of asphalt binder increase with the increase of content of graphite.This means that the addition of graphite makes asphalts stiffer.Th...     

Laboratory research on rheological behavior and characterization of ultraviolet aged asphalt

The influence of aging on the evolution of structural,morphological and rheological properties of neat asphalt was investigated by Fourier transform infrared(FTIR),atomic force microscopy(AFM) and dynamic shear rheometer(DSR),respectively.Asphalt was suffered under 20 W/m2 of UV radiant intensity and under the condition of aging time(0,48,96 and 144 h) with film thickness of 100 μm and film thickness of 50,100,200 and 500 μm after aging for 120 h,respectively,at certain UV radiant intensity 20 W/m2.Rheological results tested by DSR exhibit higher the complex shear(stiffness) modulus(G*) and lower phase angle(δ),compared to the virgin at the same test condition.The compositions analysis of asphalt before and after aging show an increase of carbonyl and sulfoxides,while a decrease of aromatic functional groups.With the increase of the component of asphaltene,obvious agglomerates of asphalten appear in neat asphalt surfaces after aging.     

沥青基路用传感器材料的试验研究

本文探讨了导电沥青基复合材料作为路用传感器的可行性。采用改进后的车辙试验和单轴压缩试验对其进行了研究,通过对实际路面荷载的模拟,向导电沥青混合料试件施加预设力,通过电阻变化得出导电沥青混合料的应力与电阻的对应关系。试验结果表明,导电沥青混合料的电阻对外加荷载的敏感性非常高,且卸载之后导电沥青混合料的电阻与时间具有良好的幂函数关系,可以将导电沥青混合料用于制备较精密的传感器。但由于导电沥青混合料的粘弹性性质,电阻回复到初始值所需的时间较长,如何应用尚需进一步研究。     

排水沥青路面新型防水粘结层的应用研究

排水性沥青路面防水粘结层作为路面结构设计中的薄层,不仅要求能够防止雨水渗透到排水沥青面层的下层,同时需要有较强的沥青层与层间的粘结能力。为了解排水沥青路面结构层中一种新型有机硅树脂防水剂以及改性乳化沥青组成的防水粘结层的实际应用可行性,对这种新型的防水粘结层结构进行了初步的防水和粘结性能测试。试验表明这种新型的防水粘结剂对于密级配沥青混凝土的防水性能随着防水剂用量的增加显著增强,同时,在防水性能较佳的防水剂用量条件下,由这种新型防水剂和乳化沥青组成的防水粘结层处理的层间粘结性能较未处理的层间粘结性能优越。综合考虑这些试验结果表明这种新型防水粘结层对改善防水粘结性能有重要意义,可以应用于排水性沥青路面结构中去。