DEPENDENCE OF THE COMPACTION COEFFICIENT ON THE NUMBER OF IMPACTS OF THE WORKING TOOL OF THE COMBINED EQUIPMENT

The article considers the process of compaction of asphalt concrete mixture with the help of the developed combined equipment, which is created as a part of the concept of high-speed construction and is designed for progressive impact on asphalt concrete and increasing its density. The main working element is a smooth rotating roller with an offset axis, whose combined impact and rolling action is realized by means of an elastically deformable belt element that provides force distribution. Each impact of the roller increases the density of the asphalt concrete. However, too few impacts will result in an insufficiently dense mix, while too many impacts will reduce the speed of the complex and may damage the already compacted layer. In order to conduct natural tests in laboratory conditions, an appropriate stand has been constructed and a methodology for conducting the experiment has been developed. Tools, fixtures and methods of taking and calculating the results are considered. Conducting six experiments with changing the number of impacts from 2 to 17 in increments of three allowed to make a dependence for compaction of asphalt concrete by the developed working body. The results showed that the compaction coefficient increases with increasing number of impacts. At first, its active growth with gradual leveling off is observed, after which the density growth becomes insignificant. This result is in agreement with existing similar studies and explains the structural and mechanical properties of asphalt concrete mixtures. It is revealed that the optimum number of passes over one pavement section without reducing productivity or under-compaction of the material is from 5 to 15. However, the obtained conclusions reflect a general character, which indicates the need for further research for other mixtures and with other compaction parameters and equipment.