PROGRESSIVE TECHNOLOGIES IN CONSTRUCTION MATERIALS SCIENCE...

PROGRESSIVE TECHNOLOGIES IN CONSTRUCTION MATERIALS

Always strive to ensure that technology in production, in engineering projects, scientific developments and other similar cases were the most progressive, advanced. However, at present there is no scientifically grounded criterial assessment of the level of progressivity of building materials technologies. If necessary, the assessment of the state of the technology produces one of its main elements - the quality of the finished product, raw materials, equipment, energy, economy, ecology. Often

for comparison, foreign experience or experience of leading domestic enterprises of a similar profile is given. As a result, a comparative evaluation of the technology is developed for one, two or more indicators, which is useful in finding ways to further improve the technological parameters. And yet, the method of comparative evaluation of the indices of individual technological operations (operations) can not give a complete and scientifically sound characterization of progressive technology; the more it can not predetermine the range of activities, in conjunction with the impact of other factors, on the effective improvement of technology in general. In this method, there is no main - generalizations, which, as we know, constitute the strength of all science and, in particular, construction materials science. With scientific generalizations, the method can be acceptable not only for the same type, but also for the different technologies.

In order to achieve these goals, it will firstly be required: a) to clearly and fairly fully describe the state of production, which can be rightly attributed to progressive, advanced technology in both semantic and quantitative terms; b) to have information about the level of world achievements in the relevant technology; c) produce the necessary criterion calculations and technology estimates. Obviously, without these three fundamental data, the ongoing research to ensure the progressivity of technologies, although they may be useful, is of an abstract nature both in terms of evaluation and technology improvement. The analysis of each of these three assumptions is described in more detail below.

SENSE AND QUANTITATIVE CRITERIA

A detailed analysis of the state of building materials technologies has shown that progressive, advanced ones include those that satisfy a certain set of extremums of mandatory indicators, expressed in both semantic and quantitative meanings. This particular complex includes the following extremes: production of high quality products; higher productivity in production with a minimum of time to produce a unit of production; maximum saving of natural raw materials with the widest possible use of technogenic and similar products; minimum fuel consumption, especially traditional, with maximum savings of thermal energy; the highest energy savings (total and specific); maximum of environmental cleanliness in both technology and materials; the maximum reduction of the material consumption, especially the metal consumption of finished products and technological equipment; minimum capital investment in a unit of output, especially when implementing new or modernized production; minimum payback period of technology with minimum cost of finished products; maximum of elements of high culture in technology and in production in general; high and stable competitiveness of products in the domestic and foreign markets.

The above indicators of the progressivity of technologies constitute a complex system into which additional ones can be added or some of them can be excluded, but with the invariable preservation of its interconnectedness and integrity. Let's briefly dwell on each indicator.

The first place in terms of specific significance in the set of indicators of progressiveness is the highest quality of products. Under the highest quality is understood, first, the unconditional conformity of products to regulatory requirements of standards or technical conditions and, secondly, mass uniformity of products produced by one or several key parameters (properties, composition, structure, external characteristics, etc.). As a key parameter in determining the homogeneity, it is advisable to adopt the optimal structure. Its presence in the ISK is fixed by the coincidence of the normalized indices of properties with their extreme values, which follows from the inverse effect of the law of the alignment. Only with optimal structures and, consequently, extremums of properties at the level of specified (or standard conditioned) with observance of statistical homogeneity of mass production, the closest relationship of the latter with production technology develops and develops, with practical methods, through technology, to the quality of finished products.

With any positive characteristics, the technology can not be classified as progressive if the product does not meet the specified requirements or is lower in quality of similar products manufactured by other technologies. The given requirements can be both at the level of world standards (achievements) and higher than them. These requirements also include the longevity of the material (product) in the construction, composed of its three time elements. Not always a high level of product quality, fixed in the pre-exploitation period, serves as an automatic guarantor of the durability of the material in structures.

The second main indicator of progressive technology - the highest productivity of the enterprise for the production of finished products, which is adequate, as a rule, the highest productivity of labor per one worker or one worker. The more high-quality products are produced per unit of time and, therefore, it is more accounted for when calculating for one worker (or working), the more progressive the technology in this indicator. As a result, the highest productivity and capacity of the enterprise as a whole are ensured. The management and the collective receive increased profit and the opportunity to update the equipment, develop production at the enterprise using the latest achievements in scientific and technical progress.

The third indicator of the progressiveness of technology is due to the minimum consumption of natural raw materials in relation to its total consumption in this production of building materials and products, or per unit of output. Than in smaller quantities is consumed rocks and minerals, including water, and with minimal waste when processing them into finished products, the more for this purpose is used technogenic raw materials, as well as by-products of ore-dressing plants, unconventional local raw materials or synthesized, the more progressive this technology. It should also add a low percentage of rejected products, a reduction in the density and size of products and other factors. The need to include the all-round saving of natural raw materials in the complex criterion of progressiveness follows from the very alarming realities of the growing acute deficit and unfavorable ecological situation in its development areas. In our country it is necessary to extract from the bowels of the Earth over 2 billion tons of natural raw materials for the production of building materials, and with a very low coefficient of its use. Much more than half of it is sent to dumps. In particular care requires a natural mineral from a group of oxides, in a liquid state called water, and in a solid state - by ice. Fresh water is one of the most valuable minerals, which is also extremely scarce, as its amount on Earth does not exceed two percent of the total water volume.

The fourth indicator of the progressiveness of technology is the minimal expenditure of traditional fuels (oil, gas, coal) as the most valuable types of natural raw materials for the chemical industry and very necessary and important for other needs in the country. This indicator also includes the need for maximum reduction in specific fuel consumption and maximum savings in thermal energy. The indicator of progressivity for minimum consumption of fuel and thermal energy increases with the decrease in the amount of heat consumed per unit of output in the enterprise per unit of time without loss of its quality.

The fifth indicator characterizes the maximum energy savings either by total consumption, or, more graphically, by the specific one attributed to a unit of production or another unit value, or by using both quantities. It must be taken into account that electric energy continues to be the most important energy carrier and its maximum saving is always required, in particular due to the all-round reduction of heat losses, excessive electric lighting, electrical overload in technological equipment. The fourth and fifth indicators of progressive technology characterize the level of resource and energy-saving technology.

The sixth indicator of progressive technology is established by the effective solution in it of two major environmental problems in construction materials science. The first is the protection of the environment in the production of building materials and products, the second is the protection of building materials, products and structures obtained by this progressive technology from the negative impact of the environment on them.

The solution to the first problem, besides the above-mentioned minimum consumption of natural raw materials, a minimum of water consumption, especially fresh water, prevention of pollution of water bodies, provides for the complete elimination of the release of harmful substances into the atmosphere, sewage or soil. In this regard, it should be noted that globally, as a result of human economic activity, 25-10 tons of pollutants are released to the atmosphere around the world: dust, gases, aerosols. In our country in the pollution of the atmosphere, the share of industrial materials is 12% among other industries. This allocation of pollutants is associated with the processing of some varieties of raw materials, transportation, storage and use of materials made from such raw materials. Separations are also possible at the stage of operation of products and structures in buildings and structures, especially with their large surface or extent, for example, pavements, airfields, roofing.

In addition to dangerous pollution of the environment, another source of environmental shocks was, as already noted in the third indicator of technology progressiveness, a rapidly declining reserve of natural resources of raw materials. Nevertheless, the exploitation of the indigenous deposits continues and is not in a shrinking size. At present, in our country there is a growing danger of a massive emergence of local quarries for the extraction of raw materials for the needs of small enterprises. A lot of quarries and pits that arise when sand, gravel, clay, gypsum and other minerals are mined by the open method not only occupy vast fertile land areas, but also concentrate around them large accumulations of empty rocks (overburden) and waste (about 30%) from stone processing. In addition, there is a constant need for a thorough and systematic verification of the inertness of the natural raw materials used and the production waste used by means of dosimeters (radiometers).

The solution of the second environmental problem, often referred to as the "ecology of materials", is to prevent the environmental impact on materials, products and structures in operation. These negative effects usually result in either biological damage of myco-, bacterio-, algolicho-, herbodesgructures, or corrosion from inorganic and organic reagents. These and other reagents can be contained in the environment at the same time. An example is the waste water of many enterprises, especially the chemical industry, and the composition of the reagents in time does not remain constant, complicating the fight against corrosion.

Effective solution of both environmental problems by technological methods has priority in assessing the progressivity of production technology.

The seventh indicator of the progressiveness of technology captures the minimum amount of material consumption, especially metal consumption, the operating basic and auxiliary equipment (equipment). This indicator also reflects a general reduction in the consumption of materials, especially metals consumed for the manufacture of finished products by the adopted technology.

The eighth indicator indicates the size of real capital investments in the organization of new technologies or modernization (reorganization) of existing ones. Obviously, the lower the volume of capital investments per unit of output, the more progressive the technology is, which affects the level of increase of this indicator. In all cases, it is advisable to use a specialized instruction to determine the effectiveness of capital investments in the construction or reconstruction of an enterprise for the production of building materials and products.

The ninth indicator of progressivity characterizes the high culture of technology and production as a whole. It is complex, because it contains very heterogeneous components. These include: the state of labor protection, safety and social comfort, sanitary and hygienic conditions of work, provision of intra-plant communication and communal landscaping, planting of the plant site and pre-factory territory. Each component of this complex indicator is usually evaluated separately and compared with similar technologies of different industries, and more often - in comparison with regulatory guidelines, for example, with safety rules, industrial sanitation, etc.

Progressive enterprises and workshops of both new and reconstructed facilities must meet the requirements of existing Sa

nitric norms, building codes and rules, etc. The illumination of factories and workshops, production sites and workplaces is regulated by the rules for the installation of electrical installations. The same applies to fire safety requirements with possible safe evacuation of people through appropriate exits.

This indicator is difficult to quantify. For this purpose, a score and expert rating system can serve.

The tenth indicator of the progressiveness of production characterizes the high organization of the use of modern means of technical control and management, is based on the achievements of the fourth part of the general theory of ICK (see page 139), and also serves as a continuation and development of the criterion of a high culture of technology and, in general, of production ninth indicator, see page 152).

The eleventh indicator is economic. Its general values ​​are usually the reduced costs per unit of output, the cost value, the profitability index, the payback period of the technology. A peculiar economic indicator is the ratio of the cost to the unit of measurement of the required key property, for example, strength. Other technical and economic indicators of production are possible. Among them: specific consumption of raw materials; the same - fuel technology, power, power, technology, and so on. All of them can be correlated with the expenditure of money.

Often, the finding of an economic indicator is closely related to the task of optimizing the technological process. A mathematically formalized problem of optimization of technology usually consists in determining the extremum conditions for some function of a finite number of variables that are included in the economic efficiency of products.

Obviously, this most important indicator of the progressivity of technology, like some others, reflects in itself a set of factors on which it depends - labor productivity, material intensity, the payback period of capital investments, etc.

The twelfth indicator characterizes the technology from the standpoint of its ability to ensure the competitiveness of finished products in the domestic and foreign markets. This indicator is directly dependent on the first indicator - quality, however, it also has its important features that help to ensure the competitiveness of the finished product. In particular, it is directly related to the indicator of the level of production culture, because only with faultless technological conditions it is possible to achieve reliable competitiveness.

Thus, a complex of indicators can assess the state of technology, although it is natural to assume that twelve may not be enough and additional ones will be required. But it is possible that twelve will be too much to characterize any particular technology; then it is advisable to reduce their number.

In such a generalized form, the expressed semantic characteristic of progressive technology is necessary, but it is important to express each indicator with a quantitative value in accordance with the corresponding dimension, and then proceed to the criterial evaluation. The latter is achieved by means of the criteria of optimality in their dimensionless expression, that is, the assignment of real numerical values ​​to the indicators of world achievements. If there are no data on the latter, then - to similar extremes of a different nature, including theoretical calculations for some idealized technologies. However, it is necessary to use all the possibilities - publications, patent analysis, newsletters, business contacts, etc., to obtain information about the latest achievements of world practice, including domestic ones, with respect to this technology.

The criterion of optimality from the twelve above in their numerical expression can be determined using simplex quantities. Their simplest values ​​are obtained by dividing the actual achievement of the enterprise by this indicator of the progressiveness of the technology in its numerical expression by a similar value in another enterprise, accepted reasonably as the "level of world achievements". If such a simplex quantity is unique for the progressivity index under study, then after its determination it becomes a numerical dimensionless optimality criterion. If, on the other hand, the actual state of the level of the progressivity index was to be estimated by several simplex quantities, then their indexing is necessary. And the optimality criterion will be summed up as a sum of simplex quantities after defining them as private divisions of the numerical value of the actual enterprise level by the extreme value of the level of world achievements, divided by the number of simplexes:

where S/ is the current simplex, n is the number of simplexes.

Obviously, the closer each simplex value to unity, the higher the criterion of optimality, and, consequently, the more effective the technology is for the considered progressivity index. However, it is possible that the optimality criterion turns out to be equal to or higher than 1. More often, however, it is necessary to implement optimizing factors that approach the criterion to 1. The simplex can be more than 1, for example, at an increased cost compared to advanced technology, if, for example, the consumption of rocks and minerals per unit of output is higher than in the case of advanced enterprises, which use technogenic raw materials instead of natural ones. But even then it is required to ensure the reduction of the simplex to 1 (see 6.4) by implementing the appropriate optimizing factors. Thus, it is possible that both an increase in positive values ​​and a decrease in the negative values ​​of simplexes, but with the achievement in both cases of their optimal values ​​equal to 1.

For progressive technology, each indicator of progressivity in quantitative terms is characterized by the criterion of optimality of the maximum value equal to 1. When evaluating the technology using 11 indicators of progressivity, i.e. with an eleven-point system, progressive technology is estimated with a total value of 11. With other scoring systems, the corresponding values ​​of the optimality criteria will also be required, for example, with 10 indicators - a value of 10, with 12 indicators - a value of 12, etc. If the total values ns optimality criterion reach extremely high values, then the actual value of progressivity is calculated by dividing the amount of actual number of criteria of optimality. For example, if the actual value of the optimality criterion is equal to 8.7 at an eleven-point scale of assessments, then the degree of progressivity of the technology is estimated to be 8.7/11 = 0.8 (more precisely, 0.79), t. 20% below the level of world achievements in this production of finished products (materials). According to the classification of estimations of technologies recommended in the theory of ISK, it looks like this: non-aggressive - 0,01-0,21; low-progressive 0,22-0,41; medium progressive 0,42-0,75; high progressivity - 0,76-1,00; Superprogressive when the criterion of optimality is more than 1.00. Hence it is obvious that the technology described above refers to the technology of high progressivity. In relation to this, additional reserves of optimizing factors can be found that can raise technology to the next higher level of progressivity.

The above method of assessing the degree of progressivity of technology allows us to move from descriptive-semantic characteristics to extreme values ​​of the corresponding indicators to a numerical estimate, taking into account the full range of progressivity indicators. But in this method there is also a certain drawback, which affects the accuracy of the evaluation aside, as a rule, underestimation of the effectiveness of the influence of optimizing factors in their implementation. This drawback is connected with the fact that, taking for simplicity of calculations the arithmetic mean of the simplex quantities,

assumed a consistent impact of factors on the technology. In actual conditions, in production, factors most often act not consistently, but in combination with each other. Simultaneous effects of several or all factors lead to synergism with the amplification (very rarely with weakening) of the final effect in comparison with the simple summation of effects from the factors that acted separately, in a sequential order of their alternation. Synergetic effect is difficult to establish analytically, but it can be determined empirically with subsequent mathematical processing of experimental data, using in particular the method of mathematical design of the experiment. In it, for the lower limit of variation, a quantitative effect can be taken on the realization of the factor without taking into account the synergism, for the upper limit - a unit; it is equal to the simplex with the highest value of the numerator equal to the denominator, as the level of world achievements. Its results are usually expressed by a complex function in the form of polynomial polynomials or regression equations. In the latter, the coefficients indirectly reflect the priority of a factor or several factors over all others taken to improve technology.

In calculating the coefficients of the regression equations, some of them take such small numerical values ​​that they are not able, as a rule, to significantly affect the magnitude of the generalized optimality criterion. Then they can be omitted and the solution of the regression equation is simplified. It is important, however, to make a preliminary check on the criteria of Fisher and Styodent.

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