Holotiuk M. Improving the efficiency of working equipment for the destruction of frozen homogeneous environments

Investigation object is the destruction process of homogeneous frozen environments on motor roads and pavements by working body of percussion. The thesis objective is to increase the efficiency of destruction processes of homogeneous frozen environments by establishing reasonable parameters of working equipment. The following research methods were used: Theoretical research was performed by using existing mechanical statements, the theory of fracture of brittle materials, mathematical analysis; Experimental research was conducted by means of visualization using strain-gauge measurements and statistical methods of output processing. The theoretical and practical outcomes are the following: the method of design and engineering calculations of working body for percussive destruction and removal of ice formations on road surfaces and pavements is developed; the experimental model of the developed working body to ruin homogeneous frozen environments is designed and tested as well as recommendations for its rational parameters are received; Main thesis provisions are introduced into the educational process for students majoring in "Mechanical Engineering". The scientific novelty is in the fact that the rational structure of percussion working body with tapered destructive elements to clear the road surfaces of homogeneous frozen environments is theoretically proved and experimentally confirmed for the first time; the destruction pattern of homogeneous frozen environments by tapered destructive elements is established for the first time, that consists in the fact that because of setting in the ends of the destructive elements of a flat rectangular blade with the height of h= 5-7 mm and thickness of а0=3-4 mm the stress intensity factor at the crack tip increases, the stable leading crack propagation is provided, the energy capacity of the destruction process is reduced; the rational parameters of tapered destructive elements are proved: the width is в=60-80 mm and sharpening angle - 2?=27-30° providing minimal energy capacity of the destruction process of frozen homogeneous environments; the rational spacing of destruction of tapered destructive elements is proved for the first time, that determines the distance ratio between adjacent destructive elements to the distance between adjacent rows of destructive elements LП / LПД = 0,7-0,8 with minimum energy indices and by providing cleaning coating quality kя= 0,85-0,90. Implementation extent: the work equipment designed for the destruction of frozen homogeneous environments was practically used by Rivne Road and Exploitation Agency resulting in positive evaluation; the calculation of economic benefit comprises 58449 UAH. Range of application: Roads and pavements cleaning from ice formations.