Aleksandr Osipov, Iaroslav Tugai
Methods of dismantling of large scale panel first mass series buildings
Kiev National University of Construction and Architecture
Abstract. In the article the current topical issue regarding development of the first large scale panel buildings dismantling methods is developed. The special emphasis is placed on the need to significantly improve the efficiency and safety of large scale panel buildings dismantling under dense urban development conditions achieved through the development and implementation of dismantling works performance methods based on principles of guaranteed ensuring of building tridimensional endurance and structures strength upon increasing the process technical and economic performance. To this end the engineering dismantling solutions are formed based on dismantling methods organizational and technological structure, which includes the following components: organization, mechanization and technology. The combination of possible solutions in terms of their specific parameters allowed developing effective large scale panel buildings dismantling methods upon dense urban development reconstruction.
Keywords:method of dismantling, large scale panel building, reconstruction, dense urban area, technological decision, technical and economic indicator.
Victor Levin, Sergey Shabelnik
Effect of shape of ultimate surface on description of concrete deformation by relations of flow theory
Donbas National Academy of Civil Engineering and Architecture
Abstract.The relations of the flow theory oriented to description of the deformation process of concrete at application of the isotropic model of hardening have been analyzed. Three ultimate surfaces of various shapes have been considered and the effect estimation of the shape to the straining relations have been made. The study tested the ability of application of a hardening function produced from the considered experiment but not the experiment to uniaxial compression as usual in other researchers. The calculated data have been compared with experimental data of H. Kupfer and A. Bambura. The simple (biaxial compression, compression-tension) and complex loading (biaxial compression) have been considered in the paper. The approximation errors of experimental data by suggested relations have been presented in the paper. It has been shown that the application of considerably more sufficient boundary conditions transform to error approximation reduction of the experimental data at least for the principal compressive stress direction up to the acceptable level both for biaxial compression region and for compression_tension region. The boundary condition version providing a sufficiently good correspondence of the calculated and experimental data. The subsequent progress of the model further development of the model assumes improvement of the law of reinforcement and demands execution of experiments on the concrete specimens in conditions of combined loading.
Keywords:concrete, flow theory, deformations/strains, error, ultimate surface.
Galya Vasilchenko
Field investigations of the thermo and physical characteristics of the exterior walls with ventilated facade systems
Donbas National Academy of Civil Engineering and Architecture
Abstract.The contemporary theories of physical processes that determine thermo and technical characteristics of the air gap in the buildings with ventilated facade systems have been analyzed. The results of field observations have been given. The minimum thickness of 15 mm air gap on the example of ventilated facade system «Marmorok». Have been considered Research was conducted in term modernized five story building at the 1st, 3rd and 5th floors with luminal starting profile of 0, 30 and 100 %. On the basis of experimental studies and theoretical calculation the air speed, air temperature and humidity in the air gap in the design conditions have been determined. The dependences of the air speed in the layer on the outside temperature have been done. The changes in humidity in the layer depending on the degree of openness of the starting profile have been found, and also it has been found out that the nature of temperature change of the gap at subzero temperatures of the outdoor air.
Keywords:ventilated air layer, temperature, humidity, air speed, thermomodernization.
Vasiliy Kravets
Systems of aspiration and gas cleaning in mixer departments of steelmaking shops
Donbas National Academy of Civil Engineering and Architecture
Abstract.Reduction of emissions from mixer departments of existing steelmaking shops is an important task to match steel industry environmental standard ISO 14 000, without which the products of the Ukrainian metallurgical plants is not allowed on the markets of the EU and other developed countries. The main components are graphite dust and fine red fume (brown smoke), which enter the atmosphere during the process of pouring iron into the mixer and discharge from the mixer in saucepan. In Ukraine, the mixers of many steel mills are not equipped with systems of aspiration, and graphite dust and brown smoke enter the atmosphere in the form of fugitive emissions, i.e. without any cleaning. At some plants there are outdated and physically worn out cleaning systems, but they are in fact often not exploited. To reduce emissions from existing steelmaking shops offices mixer, we recommend the following design and technical solutions. 1. Each mixer is supplied with an autonomous system and emissions purification, including umbrella over the neck and over the toe of the mixer, a switch rod with a sock on the neck of the gas cleaning equipment, exhauster, and chimney. 2. The capture of graphite to Cyclone SKCN-34 large diameter and brown smoke suppressant to use gaseous nitrogen. If resources are not available, nitrogen should be applied a second purification stage-filters. 3. The consumption in the aspiration to take at least the following: for the capacity of the mixer 600 t – 100 000 m3/h; 1 300 t – 150 000 m3/h; 2 500 t – 250 000 m3/h.
Keywords:mixer department, aspiration, gas cleaning, red fume suppression.
Olexandr Meneiliuk a, Kuz’ma Shavva a, Valentina Taran b
Erection of lightweight solid slabs at the construction site
a Odessa State Academy of Civil Engineering and Architecture
b Donbas National Academy of Civil Engineering and Architecture
Abstract.The known foreign and domestic construction solutions of lightweight solid slabs in the construction site were studied. An analysis of innovative technologies for the construction of slabs with light inserts in the neutral zone of solid disk was presented. For each of the solutions features of concrete and control of reinforcement protection layer were described. The basic requirements for the production of lightweight solid slabs on site were determined. Technological sequence of construction technology of slabs with light inserts was described. The article presents data on the study of costs for installation and dismantling of formwork elements. The main comparative figures on labor input and solid lightweight concrete floors have been presented.
Keywords:slab, concrete, light inserts, blackouts, labor costs.
Victoria Chayka, Olga Filimonova
Forming the microclimate in the appartments of panel house-building by the warming of the outward facade
Zaporozhian institute of economy and information technologies
Abstract.Building companies offer a wide rang of services in warming of different types of buildings. Residents of panel house-building are usually offered the outward fasade warming. We have examined how the outward warming affects the microclimate inside the apartments. Paying attention to water vapor permeability of protective layers and the formation of condensation in the outer insulation. Comparison of the properties of commonly used insulation has been done. Inadmissible violation when the external insulation of the facade leading to a deterioration of insulating properties have been given. Also negative impact of the facades with external insulation on the microclimate in the apartments in the summer has been analyzed. Striving for weatherization through the outer sealing facades in combination with the lack of proper ventilation leads to the threat of radiation exposure to radon decay products.
Keywords:warming, microclimate, thermal stability.