Basic direction of economic razvitiyAukrainy is foresee the increase of mining in the becomings complicated mining and geological conditions. Therefore the problem of maintenance-free maintenance of the mountain making gets up sharply. In a greater degree it touches the hollow making, supported in mine-out space behind lavas and exposed to the intensive displays of mountain pressure from the conduct of stoppings.That is why development of effective, zero-emission and inexpensive artificial guard buildings, foreseeing the use of minimum volume of ordinary breed joint with limiting elements, is a very actual task.
Further development of stratal deposits of minerals in the conditions of increase of depth of conduct of mountain works is attended with the problem of providing of the operating state of the hollow making. In this connection all greater distribution is found by the charts of working off sheths with maintenance of the preparatory making after a cleansing backwall, and all more attention is spared development of effective methods and facilities of guard of the preparatory making.Most cheap on financial expenses are methods foreseeing the use of ordinary breed. And, in spite of the fact that are one of most trudozatratnykh, they and most widespread. The known building from an ordinary breed is a rubble bar. For its building a breed is used from the leadthrough of hollow drifts or from the rubble drifts specially conducted after lava. Limited area of application, high labour intensiveness, considerable usadka is basic lacks of rubble bar. In addition, after usadki to 30-45% a rubble bar begins to work as a spurn, squeezing out mountain breeds in making. For the increase of inflexibility of pedigree construction application of rubble bars is offered with hard dividing gaskets between layers, parallel foundation. A steady pedigree construction can be created in this case, but from the technological point of view its erection will be very problematic. To our opinion, for diminishing of pliability of guard building, his bearing strength, and also labour intensiveness of works on erection, application of flexible dividing gaskets is needed from a metallic net.
Ground of parameters of method of guard of the hollow making by pedigree supports with dividing flexible gaskets.
For achievement of the put purpose it is necessary to decide the followings tasks:
Scientific positions which are on the defensive in-process:
Research of conformities to law of redistribution of tensions in pedigree constructions with dividing flexible gaskets for the increase of their bearing strength. The object of researches is the tense-deformed state of pedigree construction the reinforced flexible net. The article of researches are parameters of method of guard of the hollow making by pedigree supports with dividing flexible gaskets. Methods of researches: Methodical basis of researches is made by complex approach which includes an analysis and generalization of scientific literature on issue of guard of the hollow making in the affected of stoppings zone, physical design, on structural models, mathematical design with the use of PEVM.
The scientific value of work consists in opening of conformities to law of change of the tense-deformed state of guard pedigree constructions with limiting surfaces for determination of parameters of the offered method.
The practical value of work consists in development of method of guard of the hollow making pedigree supports with dividing flexible gaskets.
Design as a method of scientific research of objects of cognition is very widely used in the different branches of science, including on mountain business. In certain cases design methods are effective enough, and sometimes uniquely possible at research of model objects, inaccessible for a direct experiment.Similarity between a model and nature is determined likeness of functions carried out a model and initial system or likeness of physical descriptions of model and designed object, or in the identity of mathematical description of conduct of the initial system and its model. In every case a model can execute the role only in that case, when the degree of its accordance with the initial system is certain sufficiently strict. Such accordance is determined by the theory of similarity.
The series of models were exhaust at the different sizes of prigruzki on guard building, which made from 0 to 15kN.
As a result of working off models at the different sizes of prigruzki on guard building we are set dependences of usadki and expansion of guard building on the row of factors. The got dependences are presented on pictures 1.2 and 1.3.
Picture 1.2. Chart of dependence of size of usadki of pedigree bar without and with the flexible dividing gasket of h from the size of prigruzki F at different: to B. h and largeness of containing it breeds of df
Picture 1.3. Chart of dependence of sizes of expansion of pedigree bar without and with the flexible dividing gasket of h from the size of prigruzki F at different: to B. h and largeness of containing it breeds of df
It ensues from charts, that its pliability diminishes the increase of width of rubble bar. So at the increase of width from 3 to 6h (where h- height of bar) size pliability diminishes in 2,8-3,9 time depending on the largeness of faction, in same queue, at application of flexible dividing gasket this change will make, 1,8-2,0. Thus the size of pliability changes from 65 to 16% in the first and from 42 to 13%- in the second cases, that specifies on that packing of pedigree bar without a gasket has more intensive character, in the turn a bar with a limiting surface on the early stage begins to resist rendered on it prigruzkam.
In the free pouring of usadki of volume with 3-mya gaskets practically it was not, but at a volume without limiting surfaces usadka made about 50%.
At prigruzke of the designed volumes with the different amount of gaskets the change of usadki made about 19-30% (in most cases 19-20%). Evenness of usadki of volumes regardless of amount of limiting surfaces specifies on that forming of pedigree gruzonesuschey construction is carried out on the initial stage of its deformation and the function of limiting gaskets consists in that, to assist it and shut out expansion of pedigree volume yet to the that moment, as selfwedging of pedigree otdel'nostey will happen in a kernel.
Picture 1.4 Charts of dependence of size of usadki of pedigree volume from the amount of limiting surfaces in him.
As a result of implementation works will be produced ground of effective, resursosberegayuschikh and inexpensive facilities of guard of the reentrant hollow making artificial pedigree buildings with the use of flexible dividing gaskets.On the basis of laboratory researches on structural models the parameters of guard buildings were certain with dividing gaskets. It is set that application of flexible dividing gaskets diminishes usadku of pedigree bar substantially. Volume of necessary breed for the letup of guard building in 1,5-8 times it is less than necessary for a rubble bar.