РЕЗУЛЬТАТИ ЕКСПЕРИМЕНТІВ ІЗ ПІДБОРУ СКЛАДУ ДРЕНУЮЧОГО АСФАЛЬТОБЕТОНУ

Abstract

Abstract Introduction. It is established that draining asphalt concrete is asphalt concrete of frame type with a very large number of voids between grains of crushed stone. Unlike crushed stone-mastic asphalt concrete in draining asphalt concrete pores are not filled with bituminous sand mortar. The main feature is its porosity, which leads to a slight decrease in its compressive strength at a temperature of 50 ° C, while the shear strength of the coating is very high. It is achieved due to the strength of the crushed stone frame (high internal friction and jamming of gravel grains) and the strength of the binder that binds the grains. Problem statement. The long-term impact on the asphalt road surface of the aquatic environment is a determinant of its durability. The issue of timely removal of surface water from the pavement is a must and is solved by giving the road surface a cross slope. As practice shows, this does not sufficiently protect the road surface from the adverse effects of water. High operational safety, improved road performance is achieved by removing accumulations of water stains from the surface that reduce the adhesion of the wheels to the road surface. These qualities can be improved by the introduction of draining asphalt concrete. Unfortunately, today in Ukraine there are no normative documents that would regulate the design, manufacture and execution of works on this technology, which makes it impossible to use it in practice and limits the optimization and development of the Ukrainian road sector in this direction. Purpose. Perform an analysis of existing experience in the design of draining asphalt concrete. Theoretical and experimental substantiation of the possibility of obtaining draining asphalt concrete with a structure of interconnected open pores, which allows you to quickly drain surface water. Materials and methods. Experimental research of draining asphalt concrete. Results. An analytical review of the experience of designing draining asphalt concrete. The stages of selection of the composition of the mixture were studied and analyzed, experimental studies on the selection of the grain composition and bitumen content in the draining asphalt concrete were carried out. Conclusions. Analysis of experimental studies on the peculiarities of the selection of the composition of draining asphalt concrete found that for the production of draining asphalt concrete using crushed stone of narrow fractions, because it has a special particle size distribution, in contrast to typical dense and crushed-mastic asphalt concrete. to crushed stone materials. The granulometric composition of the mineral part of asphalt concrete mixtures for draining asphalt concrete was selected and the optimal bitumen content for mixtures with different maximum grain sizes was established. Keywords: draining asphalt concrete, asphalt mixtures, grain composition, open voids, porousity.