粉胶比对AC-16沥青混合料性能的影响

为提高沥青混合料的路用性能,采用马歇尔试验配合比设计法,研究粉胶比与沥青混合料路用性能之间的关系。基于AC-16沥青混合料设计,分别采用0.6、0.8、1.0、1.2和1.4这5种粉胶比,分析不同粉胶比对AC-16沥青混合料冻融强度、残留稳定度和高温稳定性的影响规律。研究结果表明:粉胶比的加入对于AC-16沥青混合料冻融强度、残留稳定度和高温稳定性均有较显著的影响;随着粉胶比的增大,抗冻融强度有所改善,在粉胶比为结果0.8时,达到最佳效果;对于沥青混合料的残留稳定度,随着粉胶比的增大,其残留稳定度增大,且粉胶比不宜小于1.0;沥青混合料的动稳定度也在粉胶比约为1.0时达到峰值;对于AC-16沥青混合料,考虑各指标综合效应,粉胶比选用1.0左右效果最好。     

高温下橡胶沥青胶浆特性及矿料级配优化分析

为改善橡胶沥青混合料的高温性能,提出以橡胶沥青胶浆和矿料级配为主要研究对象的优化思路。通过室内试验,首先研究粉胶比对橡胶沥青胶浆抗车辙因子和相位角的影响;然后结合橡胶沥青的特异性,对其橡胶沥青混合料的矿料级配进行选择和调整,将动稳定度和相对变形作为混合料高温性能评价指标,得出优化后的矿料级配。研究结果表明,提高橡胶沥青混合料高温稳定性的措施有:适当调整粉胶比,控制在1.2左右为宜;以水泥取代矿粉作为混合料的填料;以传统SMA级配为基础,对混合料级配作出调整,适当降低填料比例,能够实现橡胶沥青混合料高温稳定性的优化。     

沥青胶浆对沥青混合料高低温性能的影响

在对沥青混合料的高低温性能的研究过程中,往往忽略掉沥青胶浆对其性能的影响,本文主要在胶浆理论的指导下,通过研究粉肢比变化和纤维对沥青混合料的高低温的影响。实验结果表明,通过适当减少粉胶比和增加纤维量能够有效改善沥青混合料的低温柔性的松弛能力以及提高沥青混合料的高温性能。     

回收粉对沥青混合料水稳定性影响研究

通过用玄武岩回收粉代替部分矿粉的沥青胶浆进行软化点试验,以及分别用玄武岩回收粉和花岗岩回收粉代替部分矿粉的AC-13C改性沥青混合料进行水稳定性试验,分析回收粉对沥青胶浆软化点和沥青混合料水稳定性的影响,为回收粉在混合料中的应用提供一定的科学依据。     

粉胶比对AC-13C沥青混合料性能的影响

为更好地控制沥青混合料质量,提高沥青混合料的路用性能。通过对AC-13C沥青混合料级配设计,采用了0.8、1.0、1.2、1.4及1.6这5种粉胶比,分析了这5种粉胶比条件下AC-13C沥青混合料残留稳定度、冻融劈裂强度及动稳定度的变化规律。结果表明,随着粉胶比的增加,AC-13C沥青混合料残留稳定度、TSR值及动稳定度都呈现先增加后减少的变化趋势,当粉胶比在1.4左右时,残留稳定度和动稳定度取得最大值;当粉胶比在1.0左右时,TSR值取得最大值。最后得出,对于AC-13C沥青混合料,综合水稳定性及高温稳定性等指标,粉胶比选用1.4左右时混合料性能最优。     

纤维沥青胶浆高低温性能研究

采用软化点、锥入度、动态剪切、弯曲梁流变等试验方法,研究粉胶比、温度、纤维含量和纤维种类等因素对沥青胶浆高低温性能的影响。结果表明:粉胶比、纤维含量以及纤维种类对沥青胶浆的高低温性能影响较大;纤维的掺入能较大幅度地提高沥青胶浆高温稳定性,并且木质素纤维对沥青胶浆的改善效果优于玄武岩纤维;粉胶比和纤维含量增加均可提高沥青胶浆高温性能,但低温抗裂性能有所降低;纤维沥青胶浆具有显著的温度敏感性,提高温度有利于沥青胶浆低温抗裂性能的改善;粉胶比降低0.2并掺入1%木质素纤维,与原沥青胶浆相比,其对沥青胶浆流变性能的影响近似相同。     

沥青混合料高温性能影响因素分析

以车辙试验结果为判据,对AC-16C粗型沥青混合料的粗集料含量、粉胶比、沥青类型、混合料密度等因素,对沥青混合料抗车辙性能的影响进行了系统研究。介绍了研究用原材料性质、设计级配及特点、高温稳定性影响因素分析等。研究结果表明,在沥青混合料具有合理的粗集料含量及粉胶比的情况下,使用黏度较大的改性沥青及以GTM密度为标准密度控制压实度将显著提高沥青路面抗车辙能力。     

考虑胶浆黏附性的泡沫沥青冷再生混合料性能

采用正交设计方法,研究了粉胶比、沥青老化程度及老化沥青黏附试验温度3个因素对泡沫沥青胶浆与老化沥青间黏附特性的影响.利用自研测试设备,获取了泡沫沥青胶浆与老化沥青间的黏附强度,通过极差分析及方差分析,得到3个因素的影响程度及每个因素下的最优水平;结合泡沫沥青冷再生混合料（CRMFA）干/湿劈裂强度试验,确定了泡沫沥青冷再生混合料的最佳粉胶比.在此基础上,设计了3种拌和工艺.采用冻融劈裂（ITS）试验、车辙试验及无侧限抗压强度试验,分析了拌和工艺对泡沫沥青冷再生混合料路用性能的影响.结果表明：粉胶比对泡沫沥青胶浆的黏附特性影响最大,老化沥青黏附试验温度次之,沥青老化程度的影响最小;泡沫沥青胶浆与老化沥青黏附强度最优水平为粉胶比2∶1+沥青老化程度（85min RTFOT+10h PAV）+老化沥青黏附试验温度50℃;泡沫沥青冷再生混合料的最佳粉胶比为2∶1;拌和工艺对泡沫沥青冷再生混合料路用性能具有显著影响,将粗集料及沥青路面铣刨回收的旧料(RAP)与1/2的泡沫沥青拌和,依次加入细集料、矿粉及水泥,再喷入剩余1/2的泡沫沥青,拌和制备得到的混合料路用性能最优.     

沥青混合料高温稳定性影响因素的灰关联分析

沥青混合料高温稳定性对于沥青路面抗车辙性能具有重要影响,而高温稳定性又受多种因素的影响,因此,选择2种沥青、3种级配共计6种沥青混合料,进行了不同的室内车辙试验,测定了不同混合料的动稳定度,用灰色关联理论对各影响因素的影响程度进行了分析。结果表明,沥青混合料动稳定度影响因素的重要程度从大到小为最大公称粒径、软化点、粉胶比、空隙率、0.075 mm集料通过率、针入度、油石比、沥青饱和度和4.75 mm集料通过率。在此基础上,分析了各影响因素之间的关系,初步提出了沥青混合料动稳定度的预测模型。     

沥青用量与级配对OGFC混合料的高温及水稳定性能影响

本文通过调整沥青用量来改变混合料的粉胶比分别为0.6、0.9、1.2,并采用粗、中、细级配研究两者对混合料的高温稳定性以及水稳定性的影响。实验结果表明中、细级配时,混合料的动稳定度和残留稳定度随粉胶比增大而降低当级配较粗时,随粉胶比的增大而增大,但TSR则出现一直降低的现象。最后建议级配较粗时粉胶比的范围宜为0.9-1.2,级配为中、细时粉胶比的范围宜为0.6-0.9。     

Experimental investigation on related properties of asphalt mastic containing recycled red brick powder

Some properties of asphalt mastic containing recycled red brick powder (RBP) were investigated in this paper. RBP was used as filler in asphalt mastic. The investigated mastic consisted of asphalt and filler at a mass ratio of 1:1. Penetration, softening point and high-temperature viscosity were tested. Dynamic Shear Rheometer (DSR) was used to conduct frequency sweep test of asphalt mastic. The introduction of RBP resulted in reduced penetration, increased softening point, apparent activation energy, complex shear modulus in the low frequency area and high-temperature viscosity. It indicates that RBP may have some positive effect on high-temperature properties but some negative effect on low-temperature properties of asphalt mastic. It is also believed that the average compacting temperature of asphalt mixture containing RBP is 6.5 °C higher than that containing limestone mineral filler (LMF).     

The effects of using lime and styrene–butadiene–styrene on moisture sensitivity resistance of hot mix asphalt

This study focuses on determining the effects of styrene–butadiene–styrene (SBS) and using mineral filler with lime on various properties of hot mix asphalt especially moisture damage resistance. The asphalt cement was modified with 2%, 4% and 6% SBS. The lime treated mixtures containing 2% lime by weight of the total aggregate as filler. The physical and mechanical properties of polymer modified binder and binder–aggregate mixes were evaluated through their fundamental engineering properties such as dynamic shear rheometer (DSR), rotational viscosimeter (RV) for binders, Marshall stability, stiffness modulus, indirect tensile strength and moisture susceptibility for mixes. The retained Marshall stability (RMS) and tensile strength ratio (TSR) values were calculated to determine the resistance of mixtures to moisture damage. To investigate clearly the effective of SBS and lime seven freeze–thaw cycle was applied to specimens at TSR test. The results indicate that application of SBS modified binders and lime as mineral filler one by one improves the stability, stiffness and strength characteristic of hot mix asphalt. According to retained Marshall stability it is concluded that addition of only 2% lime have approximately same effect with addition of 6% SBS. Using lime together within the SBS modified mixes exhibit high accordance and exacerbates the improvement of properties. Specimens containing both 2% lime and 6% SBS, have the highest stiffness modulus which is 2.3 times higher than those of the control mixture and showed the least reduction in tensile strength ratio while maintaining 0.70 tensile strength ratio after seven freeze–thaw cycle.     

沥青混合料再生剂的试验研究

应用阿布森法从沥青混合料中回收旧沥青,然后在回收沥青中掺配不同比例的再生剂使沥青再生,通过对再生沥青进行的试验,确定了再生剂的最佳掺配比例和再生剂对沥青性能的影响规律,结果表明,利用选择的再生剂再生后的沥青性能完全满足技术要求。     

橡胶颗粒沥青混合料高温稳定性研究

通过在沥青混合料中掺入不同含量的废旧橡胶颗粒进行车辙试验研究,分析了废旧橡胶颗粒沥青混合料抗车辙的路用性能,从而验证了以废旧橡胶颗粒作为骨料的形式掺入沥青混合料中,其高温稳定性比未掺入废旧沥青混合料要好的观点。     

Utilization of municipal solid waste incineration ash in stone mastic asphalt mixture: Pavement performance and environmental impact

The objective of this study is to the use of municipal solid waste incinerator (MSWI) fly ash as a partial replacement of fine aggregate or mineral filler in stone matrix asphalt (SMA) mixture. For saving natural rock and reusing solid waste, basic oxygen furnace slag (BOF slag) was used as part of coarse aggregate. And this makes SMA mixtures contain more than 90% solid waste materials by mass. A comparative study of the performance of two mixes designed using superior performance asphalt pavements (SUPERPAVE) and Marshall mix design procedures was carried out in this research. Samples from both mixes were prepared at the design asphalt contents and aggregate gradations and were subjected to a comprehensive mechanical evaluation testing. These tests included Marshall stability, water sensibility, resilient modulus, fatigue life and rutting. In all the performed tests SUPERPAVE mixtures proved their superiority over Marshall mixtures. TCLP test for environmental impact indicated that asphalt is an effective stabilization and solidification agent for heavy metal in MSWI ash. The heavy metal leachates in TCLP tests have great positive correlation with their initial concentration in waste. But Ni is an exception that lower initial concentration leaded to higher cumulative leaching rate.     

改善片麻岩沥青混合料水稳性能的试验研究

采取掺入普通矿粉、消石灰、水泥、活性矿粉等单一或综合的措施,进行了各种措施下沥青混合料性能指标的室内试验,研究了不同措施对片麻岩沥青混合料路用性能的改善效果。试验结果表明:不同措施的改善效果不同,掺活性矿粉对提高片麻岩沥青混合料水稳定性效果好,而掺普通矿粉的水稳定性效果差。     

粗骨架沥青混合料路用性能

通过试验研究,系统分析了Superpave和SMA沥青混合料的路用性能,包括原材料性能,级配分析,混合料马歇尔稳定度,水稳定性,低温抗裂性,高温稳定度,疲劳耐久性和抗滑性能,并与密级配沥青混凝土进行了对比分析。     

沥青混合料车辙试验前后其体积参数变化规律分析

研究沥青混合料车辙试验前后其体积参数对提高沥青混合料高温稳定性具有重要意义。采用轮碾法成型沥青混合料试件,并对试件钻芯取样,分析芯样的空隙率、矿料间隙率和沥青饱和度等体积参数。结果表明:辙槽处芯样的空隙率明显小于车辙前的;油石比在4.0%附近时,轮迹两侧的空隙率大于等于车辙前的,随着油石比的增大,轮迹两侧的空隙率减小并小于车辙前的;辙槽处芯样的空隙率要小于轮迹两侧的。