S. К. Iliоpоlоv
Longevity of road constructions in the conditions of dynamic influence of transport
Rostov State Building University
Abstract. The questions of longevity of road constructions are considered in the conditions of dynamic influence of transport. It is set that influence of transporting stream on road constructions with every year is multiplied both due to the increase of intensity of motion and due to the increase of dynamic quality of influence. By basic factors resulting in the increase of dynamic influence of transport in the process of exploitation, there is the decline of evenness of road coverage and increase of the speeds modes of motion. The developed mechanic-matematical models of the system are “road construction”, taking into account the real spatial structure of road construction and dynamic character of loading, allowed to explore basic conformities to the law of conduct of road constructions at dynamic influence of transporting stream. Adequacy of the developed mechanic-matematical models was estimated by comparison of results of theoretical and models experimental researches on the motor-car roads in the process of their exploitation.
Key words: longevity, road constructions, dynamic influence, transpor stream.
S. G. Kuznetsov, I. I. Ananyan, L. М. Bogak
Functional transformation of built up area
Donbass National Academy of Civil Engineering and Architecture
ESТC «Town-planning»
Abstract. The paper deals with the problems which appear due to the failures in town planning when designing the existing built up area in the central part of the city, which lead to the worsening of the comfort conditions of the city dwellers. Results of technical economical investigation and research of the built up area are given in the paper.
Key words: polyfunctionality of built up area, compression of built up area, capacity of residential built up area.
V. Bratchun, N. Zaychenko, O. Khalyushev, O. Sakhoshko
Electrophysical surface modification of Portland cement by dispersion mineral additives
Donbas National Academy of Civil Engineering and Architecture
Abstract. The presence of the electric charge on the surface of cement and mineral additives affects on their electrostatic interaction. Its character and value depend on the integral charges of surfaces. It can be possible to regulate the integral charges of surfaces by high-voltage electrostatic polarization in the corona field. Adhesive interaction between the oppositely charged particles of cement and mineral additives results in formation of the combined aggregates with decline of specific surface. It is affected on rheologyc properties of cement pastes, process of structure formation and composition of hydrate products of Portland cement as well as on the indexes of cement paste durability.
Key words: рortland cement, mineral additives, spherical particles, high-voltage polarization, active surface centers, adhesion, hydrate products.
V. V. Mozgovyi, О. N. Besarab, О. О. Zhukov, А. N. Onishchenko
Increase of firmness from the cracks of asphalt-concrete layers of city travelling clothes
National Transport University
Abstract. The thesis has been devoted to the development of the calculation method for crack resistance of asphalt-concrete layers with regard to load action time. The classification of load conditions according to typical sections is developed. The method for determining horizontal stretching stresses depending on load action time, that can cause asphalt-concrete layers cracking on single or multiple load applications has been motivated and developed. The boundary state conditions describing asphalt-concrete layer cracking at different time and load operation are formulated. Theoretical and experimental studies have shown the regularities of crack resistance of asphalt-concrete layers due to the influence of transport, climatic, constructive, material and technological factor. The possibility of increasing crack resistance of asphalt-concrete layers due to rational targeting of pavement construction and the use of modern material and technological approaches has been proved. The results of practical tests are given.
Key words: crack resistance, asphalt-concrete layers, thermal and rheological characteristic, load action time, stressed and deformed state, boundary state, thermal and rheological sensitivity and asphalt-concrete longevity.
L. I. Bazzhin
Mathematical models of elasticity modulus of bituminorus concrete on the basis of production grain composition of mineral part
Donbass National Academy of Civil Engineering and Architecture
Abstract. There is no possibility to control bituminous concrete properties by sand fractions as sand is not screened under worleing conditions. Due to computerized process of mathematical modelling one can choose such interaction between aggregate fraction, mineral powder, bitumen and its penetration which can provide adequate regression models of high quality and sufficient prognostic ability.
Key words: aggregate fractions, model, optimization, prediction.
L. I. Dvorkin, O. L. Dvorkin
Designing of structures concrete with active mineral additives
National University of Water Management and Wildlife Management
Abstract. In the article the method of design of concrete mixtures with finely divided mineral admixtures on the basis of using the “resulted cement-water ratio” and multi coefficient in the formula of concrete strength is offered. That allows to take into account the influence of additional factors on concrete strength and multiply “calculation power” of the accepted dependences. The algorithm of design of concrete mixtures with ash admixture and examples of algorithm realization is given.
Key words: “resulted cement-water ratio”, multi coefficient, “cementing efficiency”, amount of sand in the mixture of fillers.
V. Zolotariov, V. Malyar, Yu. Tkachuk
The rheological model of asphalt concrete
Kharkiv National Automobile Highway University
Abstract. The rheological model of asphalt concrete is offered. The model’s kernel is exponential equation. The parameters of model can be definet from experimental data of dependences of flexibility from time of action of load. For asphalt concrete the verification of applicability of this model is executed on bitumens of the three structural-rheological types.
Key words: а sphalt concrete, bitumen, model, rheological, flexibility.
Ye. W. Klymenko, V. S. Dorofeyev
Methodology of assessing of the technical condition of ferro-concrete designs
Odessa State Academy of Civil Engineering and Architecture
Abstract. In the article substantive provisions of definition of a technical condition of ferro-concrete designs are induced. Methodological aspects of reception of the experimental information on a condition of separate designs and mathematical model of forecasting of a condition are considered.
Key words: ferro-concrete constructions, technical condition.