Pakholak Raman, Plewa Andrzej, Gardziejczyk Wladyslaw
Faculty of Civil Engineering and Environmental Sciences, Bialystok University of Technology, 15-351 Bialystok, Poland.
Materials (Basel). 2021 May 27;14(11):2884. doi: 10.3390/ma14112884.
Low-noise asphalt mixtures are characterized by increased air void content. Their more open structure contributes to faster degradation within the operating temperature range. For this reason, binder modification is used in their production. The correct selection of modifiers allows one to significantly improve the technical properties of the mixtures. The article presents the results of tests of six types of mixtures: stone mastic asphalt (SMA8), porous asphalt (PA8), stone mastic asphalt reducing tire/road noise (SMA8 LA) and stone mastic asphalt reducing tire/road noise, with 10%, 20% and 30% content of rubber granulate (RG). Bitumen 50/70 modified with copolymer styrene butadiene styrene (SBS) and crumb rubber (CR) was used for the production of the mixtures. In order to determine the differences in the technical properties of the mixtures, the following parameters were tested: stiffness modules by indirect tensile testing of cylindrical specimens (IT-CY) in a wide range of positive temperatures, and resistance to permanent deformation using the British and Belgian methods with the use of double wheel tracker (DWT). The test results and their analysis confirmed that there was a significant improvement in the IT-CY stiffness modules of SBS and CR modified mixtures. Replacing more than 20% of coarse aggregate with RG causes a significant decrease in the stiffness of the mixture (by 90% in relation to the reference mixture SMA8 LA). The SMA mixtures obtained lower values of rutting resistance parameters (WTS and PRD) in water (Belgian method) compared to the results obtained in the air tests (British method). On the other hand, mixtures of PA, thanks to the compression of stresses in pores filled with water, obtained better results when the rutting resistance test was performed in the water (Belgian method).
低噪声沥青混合料的特点是空气空隙率增加。其更开放的结构导致在工作温度范围内更快降解。因此，在其生产中使用了粘结剂改性。正确选择改性剂可显著改善混合料的技术性能。本文介绍了六种混合料的测试结果：玛蹄脂碎石混合料（SMA8）、多孔沥青混合料（PA8）、降低轮胎/路面噪声的玛蹄脂碎石混合料（SMA8 LA）以及含有10%、20%和30%橡胶颗粒（RG）的降低轮胎/路面噪声的玛蹄脂碎石混合料。用苯乙烯-丁二烯-苯乙烯共聚物（SBS）和胶粉（CR）改性的50/70号沥青用于生产这些混合料。为了确定混合料技术性能的差异，测试了以下参数：在较宽的正温度范围内通过对圆柱形试件进行间接拉伸试验（IT-CY）测定劲度模量，以及使用双轮车辙试验机（DWT）采用英国和比利时方法测定抗永久变形能力。测试结果及其分析证实，SBS和CR改性混合料的IT-CY劲度模量有显著提高。用RG替代超过20%的粗集料会导致混合料刚度显著降低（相对于参考混合料SMA8 LA降低90%）。与在空气中试验（英国方法）得到的结果相比，SMA混合料在水中（比利时方法）的车辙抵抗参数（WTS和PRD）值较低。另一方面，PA混合料由于孔隙中充满水时应力的压缩，在水中进行车辙抵抗试验（比利时方法）时得到了更好的结果。
