Victoria Mazur, Elena Novitskaya
Design Features of Indoor Swimmimg Pools Buildings with Internal Thermal Insulation Contour
Donbas National Academy of Civil Engineering and Architecture
Abstract. During the operation of swimming pool buildings, a special air environment is formed in the bathroom room with increased values of temperature, humidity, and chlorine-derived vapors as a result of water treatment in the pool basin ect. These factors reduce the heat protective properties of enclosing structures, lead to accumulation of excessive moisture in them and cause the corrosion of metal structures and element and, as a result, it brings about pre-testing wear of internal and external building structures. Untimely implementation of current and major repairs, changes in heat engineering and sanitary requirements have led to the need to solve a set of tasks related not only to additional insulation of enclosing structures, but also to the isolation of adjacent premises of buildings of indoor swimming pools from the adverse effects of wet air space of bathrooms.
Keywords: indoor swimming pool buildings, factors, durability, internal heat conservation insulation contour, envelopes and supporting structures.
Evgeny Arifyev, Sergey Matvienko, Vladislav Komlev
Investigation of the Influence of the Destroyed Object Position relative to the Extreme Support of the Excavator on the Efficiency of the Hydraulic Hammer Working Process
Donetsk National Technical University
Abstract. The developed mathematical model of working process of the system «excavator-hammer» takes into account design parameters of the breaker and properties of the destroyed object. Using the developed mathematical model, a computational experiment was performed, as a result of which diagrams of the forces arising in the structural elements of the excavator and hydraulic hammer were constructed: in the stroke limiters of the wedge, in the stroke limiters of the striker, in the suspension of the excavator and attached to the destroyed material. It was found that with the maximum extension of attachments (boom and hydraulic hammer handle), the value of the reduced weight of the excavator practically does not affect the forces in its suspension, and they are maximum for the entire range of measurements. It is established that the position of the destroyed object relative to outer supports of the excavator has a significant impact on workflow efficiency breaker; minimal removal of the destroyed object allows you to implement almost in half twice great efforts impact on destructible material with minimal effort in the suspension of the excavator.
Keywords: hydraulic hammer, excavator, force, object of destruction, excavator suspension.
Dmitriy Belitskiy
Theoretical Research and Experimental Testing of a Screw Anchor Grappler for the Firm Ground Development
Donbas National Academy of Civil Engineering and Architecture
Abstract. The article presents the results of long-term research of grab working bodies for earthworks. The branch of application of grabs for earthworks and the reasons for their insufficiently widespread use are determined. A new method for developing soil with a grapple in a closed power flow «working body – soil array – working body» is proposed. The theoretical substantiation of the efficiency of working processes of a grapple with a screw anchor in the development of strong soils is given. A working design of a grappling bucket with a drive screw anchor was made and tested. The results of field experimental studies of this working body are presented. The increase in the filling coefficient and reduction of the energy intensity of the digging process on solid soils, due to the use of a screw anchor, have been confirmed. It is noted that the parameters of mass and stability of the base machine are not the main determining parameters of the process of digging with a grapple with a screw anchor.
Keywords: grapple, earthwork, strong ground, screw anchor.
Ekaterina Boroday
Influence of Nа2O Content on the Stone Structure Formation of Alkaline Binders in Magnesian Refractory Concretes on Periclase and Spinel Binding
Donbas National Academy of Civil Engineering and Architecture
Abstract. Alkaline magnesia binders of periclase and spinel compositions based on aqueous solutions of sodium silicates are proposed. The influence of Nа2O content in alkaline binders on the processes of stone structure formation of binders is investigated. The temperature of deformation of the binderstone under load and the electrical conductivity of the binderstonein the temperature range of 20…1 400 °С, are determined. It was shown that heating above 550 °C causes a jump-like increase in the mobility of sodium cations of the binder matrix. This leads to ordering of the structure of amorphous products of binders, and also involves inert fillers in the recrystallization process. The interaction of these compounds with more refractory fillers leads to the formation of a ceramic binder from more refractory crystalline phases, which favors compaction, increased strength and reduced open porosity of the binder stone. The thermomechanical properties of concrete based on the proposed binders are determined.
Keywords: refractory concretes, periclase, spinel, liquid glass.