The article describes the application of rolled floor materials for sound insulation of impact noise by the floors. A detailed classification of such materials is given, including such materials as linoleum, rubber linoleum and carpet. The described method is appropriate for testing the floor to obtain the frequency characteristics of the normalized level of impact noise of the whole structure and for the frequency characteristics of improvement of sound insulation due to the use of roll coverings. Methods for normalized impact noise level indices calculation in case of composite construction and only roll covering are also briefly described. A new semi-graphical method for constructing the frequency response of reducing the level of impact noise by floor covering for inserted floors is presented. A computational model for solving the contact problem of the impact noise isolation by floor in the form of an oscillatory system, consisting of an absolutely solid body and a two-layer elastic medium, is presented. The solution of the contact problem for obtaining an adjustment for reducing the normalized level of impact noise due to the application of a roll material is shown. The equation for frequency of crumpling for the linoleum surface crumpling in the process of standard striking machine’s impact is shown. The effect of local crumpling occurs and the growth of sound insulation starts in two-layer floor from this frequency’s value. The analysis of calculations accordingly the proposed calculation method is carried out. The practical algorithm for semi-graphical method and for the frequency response plotting of impact noise sound insulation improving by the roll floor covering is proposed. Graphs of the magnitude of impact noise improvement by the most common roll materials, that can be used to obtain the frequency response of impact noise isolation by a two-layer floor, are given.

The results of the chemical thermal treatment (CTT) of tantalum in a solid carbon- containing medium in the temperature range from 1000 to 1300 °C were presented. CTT consisted in heating a workpiece with a working medium in a container made of a refractory material. The induction heating method was used for heating. After strengthening treatment, tantalum samples were characterized by increased hardness, which grew from 140 to 1100 HV0.02.

This publication has recommendation for choosing and applying the technological infrastructure equipment, which can improve the method of large dimension frameworks lifting in buildings and constructions erection. As experimental researches and construction practice showed while increasing the ceiling panel thickness till 350-450 mm the adhesion force is enhanced and can reach 50-70% by ceiling panel mass. In that context the necessity to develop the method of adhesion force determination and find technological equipment for decreasing this force is appeared purposely for enhancing the operational efficiency of load weight-lifting equipment. The experimental researches were occurred for purpose to find out the dependence of adhesion force off amount of factors. The analytic expression, allowing calculating adhesion force, was derived after mathematical elaboration of results.

This paper presents an experimental comparison of various multilayer frame-sheathing structures and describes the effect of their design features on their own sound insulation. The paper discusses the dependence of sound insulation on material and type of the frame, the amount and density of the filler, the number and type of facing layers, the presence of a damping layer and a divided base.