#2 (35), 2009
Research and design of
spherical FIVE-BAR slider-mobile guide (S-MG) mechanisms with
dwells of output link. N. Davitashvili. “Problems of Mechanics”.
Research and design of spherical five-bar slider-mobile guide mechanisms with two degrees of freedom with dwells of output link is given. At the first stage of research the kinematic analysis of these mechanisms is given. Further, two types of mechanisms are investigated: with dwells of output link -rocker and slider. It is shown, that for one motion cycle of an input link the output link in extremity positions has two stops. The problem of design of spherical five-bar slider-mobile guide mechanisms with dwells of output link is solved. 4 ill. Bibl. 20. Engl.; sum. in Russ.
General Principles of Drivelines Terminal Control. C. Aksu, A. Milnikov. “Problems of Mechanics”.
General Principles of Drivelines Terminal Control are suggested. The terminal state control problem applied to Drivelines Control is defined. It is shown that on the base of Driveline acceleration measurement it is possible to define a variational problem, solution of which permits to synthesize general Control function of Drivelines control process. The last function covers various particular control problems. It is shown, that these problems can be naturally defined by choosing of corresponding boundary conditions. As an example of such particular cases a problem of Acceleration is solved. The singularity problem in control function is discussed and solved. Conception of control process transient component is defined. Conditions of its presence are defined. 1 ill. Bibl. 5. Engl.; sum. in Russ.
TO QUESTION OF
OPTIMIZING CALCULATION OF MULTIMASS MECHANICAL SYSTEMS OF DRIVES. T.
Mchedlishvili, G Gratiashvili, M. Lomidze, A.
Asatiani, L. Ivanishvili. “Problems of Mechanics”.
The major problems of optimizing synthesis of widely used in practice mechanical systems of drives (ÌS) are the problems connected with reduction of dynamic loadings in elastic links of multimass systems. Despite of many known results of the specified problems solution, the last nowadays remain rather actual and first of all in the appendix to structurally-difficult systems, in particular, to systems with the branched out and circular-type structures. In the present work are considered the questions connected with working out of the basic approaches to construction of applied methods of parametrical synthesis of multimass systems of drives, the dynamic loadings directed on reduction in elastic links. Bibl. 8 Engl.; sum. in Russ.
SPECIAL CONDITIONS OF THERMAL ENERGY
TRANSFORMATION AND INFRINGMENT OF SECOND LAW OF THERMODYNAMICS A.Aptsiauri. ”Problems
of Mechanics”. “Problems of
In the given work on an example of direct and reversible cycles of thermal installations is shown that if in a cycle of the thermal pump process of cooling of a working body and accumulation of taken away heat on an intermediate body occurs at the temperature exceeding an average on entropy value of temperature in the course of cooling of a working body, together with a cycle of the thermal engine, possibility of reception of thermal or mechanical energy at the expense of energy of environment is created. At the same time is offered ellementary example of the paradoxical converter of thermal energy. 5 ill. Bibl. 3. Engl.; sum. in Russ.
The theory of turn of the adaptive motor vehicle chassis. R. Makharoblidze, Z.
The theory of turning of the adaptive motor vehicle chassis intended as power units in small farms, is offered. A calculating formula for radius of turning is deduced for two variants: drive of all the six driving and steered wheels and without drive of front steered wheels. By the calculating formula are considered: lateral leading away of front steered wheels; re-distribution of the load on the wheels; hook resistance; coefficient of the differential gear black system; distance between centers of jointed in pairs tandem wheels constituting a counter-balanced suspension and other geometric, kinematic and dynamic parameters. The research results can be used in determining of exploitation indices of perspective mobile power units in the stage of their design. 4 ill. Bibl. 5 Engl.; summ. in Russ.
positions of belonging to coupler spherical mechanisms points by sphere
rotation method. Z. Natsvlishvili, G. Namgaladze,
In the work is considered graphic method of definition of geometrical figures movement on the spherical surface which is the basic problem for the kinematic analysis and synthesis of spherical mechanisms. Is offered the new approach to the solution of problems of geometry in space which allows on the basis of elementary constructions effectively define position of the points laying on coupler of spherical mechanisms. Practical application of the developed technique to the solution of the problems connected with kinematic research of complex spherical multilink mechanisms is shown. 3 ill. Bibl. 3. Engl.; sum. in Russ.
KINEMATIC AND DYNAMIC
CONDITIONS ON THE INTERLAMINAR BOUNDARIES IN THE THEORY OF SHELLS WITH THE USE
OF SEVERAL BASIC SURFACES. A.
Tvalchrelidze. “Problems of Mechanics”.
The deformation of multi-layer shells should lead to the disturbance of the cohesion of layers due to their detachment from each other in the normal or tangential directions. This should lead to the significant changes in the mechanical behavior of shell, in its stress-strained state. There are given in the article the settings of the corresponding conditions on the interlaminar boundaries in the theory of shells with the use of several location surfaces, where the front surfaces of layers are used as the location surfaces. 3 ill. Bibl. 2. Engl.; sum. in Russ.
OF remaining life of pressure vessels
and apparatuses. G.
Japaridze. “Problems of Mechanics”.
Article is devoted to problems of definition of the remaining life of pressure vessels and apparatuses. Stages of the remaining life definition are resulted. In particular, the mothods of carrying out of technical diagnostics and design formulas of criteria of the limiting condition on the remaining life which application probably to spend an establishment of the remaining life of pressure vessels and devices. Bibl. 3 Engl.; summ. in Russ.
To problem of estimation of degradation processes in concrete and bridge
structures reinforcement. T. Churadze, B. Maisuradze, n. Maisuradze, B. Chigvaria. “Problems of Mechanics”.
Is developed the techniques for research of condition of concrete and reinforcement of bridge structures. Thus is offered to estimate the damage rate of concrete and reinforcement of bridge structures on the basis of statistical analysis of the thickness of concrete protective layer and joint influence of casual processes: carbonization, frosty damage of concrete, diffusion of chlorides and reinforcement corrosion. The obtained data can be used for development of probabilistic estimate technique of bridge structures. 3 ill. Bibl. 5. Engl.; sum. in Russ.
reliability control of Baku-Tbilisi-Kars railway on stages of design and
construction. E. Moistrapishvili, M. Moistrapishvili, N.
Rurua, B. Bregadze. “Problems of
In the work are considered the problems of permanent way components reliability and are formulated the problems of international project Baky-Tbilisi-Kars new railway reliability control. Are analyzed two basic groups of impact factors: subjective and objective factors, which undergo on the object reliability degree. Are indicated such ways of impeding factors exception as making the objective and competent examination and carrying-out of engineering supervision for construction with purpose of according normative and technical and economic documentation requirements assurance. Bibl. 3. Engl.; sum. in Russ.
Pulsation flow with
V. Tsutskiridze, L. Jikidze. “Problems of Mechanics”.
It is considered pulsating flow of electro-conductive viscous incompressible liquid between two parallel walls, which is caused by drop of pulsative pressure and by pulsative motion of walls when external homogeneous magnetic field acts perpendicularly to the walls. Bibl. 9. Engl.; sum. in Russ.
SELECTION OF WELDING FLUX FOR RESTORATION OF WHEEL PAIR’S WORN COMBS WITH
BUILD-UP WELDING TAKING INTO CONSIDERATION CLIMATIC CONDITIONS. P. Kipiani, O. Kikvidze, S. Mindadze, A. Chumbadze. “Problems of Mechanics”.
The railway rolling-stock’s components and units represent the elaborate complex of tribological systems, of the operation reliability of which, in many respects, depends the safety of transportation. In the wheel-rail pair, in which there is reproduced the rolling friction and friction with the slippage, there are wearing the work surfaces and periodically there is required the restoration of the geometric dimensions of the worn surfaces with the build-up welding. In order to restore such work surfaces there is required the differentiated selection of the build-up welding materials and their preparation before the build-up welding, taking into consideration the climatic conditions of the region, in which there is carried out the build-up welding. 2 ill. Bibl. 5. Engl.; sum. in Russ.
In article are considered such caused by raised level of motorization the undesirable phenomena, as growth of traffic accidents and deterioration of environmental safety. are analyzed the existing situation and the questions put and executed in the world under the decision of this problem. It is noticed, that safety of traffic is the by the most considerable social and economic problem put by motorization and the organization of movement and perfection of its technical equipment concerns all complex of questions in which number the first is corresponding development of a road infrastructure. In the form of an example one of ways of the decision of the offered problem is offered: the technical and economy substantiation of the new tunnel construction through Surami ridge. Is defined, that it is necessary to develop legislative base of traffic safety on the basis of scientifically proved recommendations and to carry out actions for stimulation of highly skilled experts. Bibl. 8. Engl.; sum. in Russ.
AN ELASTIC BODY IN THE SCALAR FIELD. G. Karseladze, G.
Using representations of solutions of a system of homogeneous equations of static of two component elastic mixtures, the concrete problem is solved when the contact curves is a circumference. The solutions of the problem are obtained in the form of absolutely and uniformly converging series. Bibl. 4. Engl.; sum. in Russ.
is considered the expediency of lightweight concrete application in complex conditions of underground construction. spent by authors research of structural and technological parameters of lightweight concrete on local porous fillers of Sagamo deposit have shown, that these concrete can be applied in underground transport construction. 3 ill. Bibl. 12. Engl.; summ. in Russ.