METHODS OF RISK REDUCTION OF INFRINGEMENT AND COUNTERFEITS IN CONSTRUCTION
Pages 5-13
DOI: 10.22227/1997-0935.2016.10.5-13
Articles count - 15
Pages - 159
Pages 5-13
DOI: 10.22227/1997-0935.2016.10.5-13
Pages 14-23
F.O. Schechtel’s private house on Bolshaya Sadovaya Street in Moscow built in 1910 became a peculiar result of creative activity of the most famous architect of an era of “Silver age” of the Russian culture. The highest professionalism of the architect was expressed not only in composite decisions and the system of decor of the building, but also in organizational and technical aspects of his construction. The former F.O. Schechtel’s mansion for several decades has been one of the centers of Moscow’s cultural life. The memorial value of the house consists not only of its architectural advantages. The building keeps the memory of F.O. Schechtel - a first-class architect, stenographer, illustrator and graphic artist, a master of applied art, a public figure and a teacher. He personified the best qualities of Russian intellectuals: high ethical standards and active living position. The activity of the architect Schechtel was exclusively fruitful both in quantitative, and in qualitative sense. There are about fifty buildings in Moscow which were constructed according to his projects. Each of them comprised opening and generating of a new direction or introduction of new methods of construction. Schechtel gave other architects an opportunity to further develop these methods. The structures built upon Schechtel’s projects in many respects have defined unique lines of Moscow city landscape of the end of 19th - the beginning of the 20th centuries. Numerous relatives of Schechtel lived in the mansion and in its wings in addition to the head of the family. The contribution of each of them to the development of the Russian culture is significant.
DOI: 10.22227/1997-0935.2016.10.14-23
Pages 24-34
The use of crushed concrete scrap, the volume of which is quite essential, is constrained by the regulatory framework and poor studies of stress-strain characteristics of concrete. In order to solve this problem it is necessary to conduct comparative experiments with the aim of obtaining the strength and deformation characteristics of concrete, which will allow determining the possible list of structures for industrial and civil objects. Tests were carried out on the assessment of prism strength, modulus of elasticity, coefficient of lateral deformation, the maximum compression strain, tensile strength in bending as well as tests of reinforced concrete beams produced of the same compositions for evaluation of failure load, strain and deflection diagram construction with the aim of identifying distinctive characteristics of strength and deformation characteristics of concrete obtained of crushed concrete waste in comparison with the characteristics of concrete made of granite macadam. The results of the investigation show that the use of crushed concrete waste in reinforced concrete structures is quite allowable and there is no need in serious adjustments in the calculations, especially for concretes of low grades.
DOI: 10.22227/1997-0935.2016.10.24-34
Pages 35-44
Analytical solutions have definite advantages over numerical ones. It is quite complicated to find solutions for a whole class of structures different in the number of bars or panels if we speak about girder trusses. The solutions obtained in a symbol form may be analytically investigated depending on all the parameters characterizing the structure. This allows educing the distinctive features of the systems and finding possibilities for optimization in terms of mass, strength and rigidity. At the present time the induction method is the most efficient to obtain analytical solutions for a number of trusses. Using computer mathematics system Maple the author obtained analytical expressions for deflection of a flat statically determinate parallel-flanged elastic truss depending on the number of panels at uniform and concentrated load. It is shown that the rake angle of a free support greatly influences the stiffness of a structure. The graphic charts of the dependence of deflection from the number of panels at a fixed span length and a given load show extremum. The author obtains asymptotic characteristics of the deflection and expressions for stresses in the most compressed and tension bars. It is also shown that the solution type for a deflection isn’t changed in case of different loading types and has a form of a polynomial of not more than third degree in correspondence with the number of panels in half of a span.
DOI: 10.22227/1997-0935.2016.10.35-44
Pages 45-57
The gathered experience of design and construction of objects with the use of grid structures confirms the expediency, efficiency and flexibility of their minimum technical solutions providing increased strength and resistance to progressive collapse. From the general range of modern metal designs using shaped tubes (bent and welded profiles) the article observes blocks of roofs and ceilings made of cross-type farms «Pyatigorsk» as the most step-ahead solutions. Due to the small size they are conventionally classified as «pocket» modules produced all-welded. Prospects of the use of shaped tubes of round and oval cross-sections for further modernization of farms and other cross-lattice structures are presented. The article demonstrates quite acceptable accuracy and ease of optimization calculation of oval cross sections according to an approximation method. The authors describe a new technical solution for lattice structures, which contributes to the improvement of their technical and economic characteristics. Reduction in the consumption of structural material when implementing such a solution is discovered by the example of roof trusses, as well as increase of the reliability and structural safety of buildings and structures by approximation of lattice structures to their design schemes (models) in the form hinged-rod systems.
DOI: 10.22227/1997-0935.2016.10.45-57
Pages 58-68
The issues of bearing structures reliability for energy lines are of special importance in case of the use of single post horizontally loaded pile foundations of power lines and contact system supports. The required level of operational reliability of single post horizontally loaded supports in case of variability of strain-strength features of foundation soils along the route may be provided by using optimal sizes and number of foundation beams creating additional reactive impedance of soil to the loaded support. Foundation beams laid in soil perpendicular to a horizontally loaded support for increasing its bearing capacity are rather widely used. Though the issues of technical and economic substantiation of the choice of optimal sizes and number of beams influencing the strain and bearing capacity of power lines and contact system supports haven’t been studied enough. Basing on the experimental and theoretical studies the authors proposes his assessment of technical and economical efficiency of the use of foundation beams depending on their geometrical parameters, the amount and height of horizontal loading on a support.
DOI: 10.22227/1997-0935.2016.10.58-68
Pages 69-79
Pools play an important role in people’s life. They answer people’s demand in rest and improve their health. At the same time pools are rather important for industrial use, for example in construction industry. In order to solve different construction problems it is essential to investigate the influence of microclimatic parameters on construction materials and structures. For this aim pools are in demand as special test sites for construction materials and structures in different environmental conditions including the case of a direct water impact. The efficient use of pools presupposes the necessity of constant hydroclimatic contro: air humidity and temperature, water temperature, chemical composition of water and air. Classification of pools of different purposes is presented in the article. The author considers the main problems of operation of pools as objects with complicated air-and-water environment. The questions of maintaining optimal microclimatic parameters in a pool are considered. The necessity of use of the control system of a microclimate, its efficiency, profitability and social effect of its implementation is described. A mathematical model of the thermal mode of a pool area is constructed. The process of indoor temperature regulation in the pool is considered.
DOI: 10.22227/1997-0935.2016.10.69-79
Pages 80-93
A sustained pace of construction of dams and dikes using water resources and intensive development of underground space in the construction of buildings and structures require ensuring anti-seepage measures. For efficient stoppage of fluid flow a variety of methods are applied such as cement and grout curtains, teeth, core walls including ones made of soil-cement mixtures performed by the method of diaphragm wall. The following characteristics are the main selection criteria of the material composition for a diaphragm wall : permeability, strength, deformability, efficiency. Clay-cement-concrete (CCC) is one of the materials satisfying all the above characteristics. The influence of the components used to prepare CCC mixtures on its strength and deformation characteristics was the main objective of the performed study. In order to solve the task, the formulas of CCC used at the objects of hydroengineering construction have been considered. For analyzing the influence of the components of CCC on its characteristics, the dependences of compression strength and deformation modulus of CCC on water-cement and water-astringent ratios have been built. The dependence of compression strength of CCC on the cement/bentonite ratio was built as well. The analysis of the dependences defined that the compression strength of CCC depends primarily on water-cement ratio and the amount of cement used in the composition. The increase in the value of water-cement ratio and water-astringent ratio leads to monotone decrease of the compression strength of CCC and the deformation modulus of CCC. Change of the quantitative content of one or more components of CCC composition allows controlling physical-mechanical characteristics of the anti-seepage element which is an important advantage of clay-cement-concrete. The performed analysis of the influence of CCC formula on its physical and mechanical properties can be used to select the optimal composition of CCC when solving specific hydroengineering tasks.
DOI: 10.22227/1997-0935.2016.10.80-93
Pages 94-104
At the present time profound economic and political changes are happening in Russia, which directly influence the state and development speed of the construction industry. The consequences of the crisis affected business activity construction companies in Russia. The prospects of the further development of construction and investment sector are possible only in case of creation of competitive products: creation of construction objects with accound for market demands, application of modern construction technologies and high-quality materials, reduction of labour, materials, energy costs per unit of construction production, decrease of bureaucratization of the procedures and minimization of shadow economy influence on order distribution. This is possible only in case of efficient interaction of the participants of construction and investment sector. The author considers the concept of stakeholders and the problem of interaction of the participants of construction-investment sector due to the lack of attention of professional community to the corresponding field of knowledge - the stakeholder theory. On meso-level the diversity of functional roles resulting from the main provisions of this theory, greatly influences the strategic positions of the development of the field. The author also considers the use of bank guarantees and bonds and other issues for improving the sphere of activities of companies with a great number of stakeholders.
DOI: 10.22227/1997-0935.2016.10.94-104
Pages 105-111
The procedure of evaluating and selecting tender offers is not only an important element of the control system of investment and construction activity but is also an effective tool to increase its efficiency due to optimization of construction works price, reduction of their duration, stimulating innovations in the production, increasing the quality and engineering safety of construction production. At the recent time when new organizational forms and control schemes of investment and construction activity are appearing the system of competitive bidding gains more importance and new functions, because the choice of construction organizer and contracting companies directly influences the results of the construction. The authors consider the task of selecting the bidders’ offers which is a multicriterion task. The offers are evaluated according to the set of parameters reflecting the effectiveness of investment and construction projects. The criteria selection is based on the fact that the proposals of the organizer of construction and the contractors are related to the cost of works and to the deadlines which directly affects the implementation parameters of investment and construction projects.
DOI: 10.22227/1997-0935.2016.10.105-111
Pages 112-119
The main source for the development of construction projects with energy-efficient technologies in use is investments. The traditional approaches of risk management: insurance, diversification and redundancy only raise the cost of the construction project, which has a negative impact on the investor’s decision to invest. In order to solve this problem an information system has been developed, which is based on the principle of insightful analysis of the potential “pure” risks and a list of recommendations of risk management. This tool allows identifying all the weaknesses of a construction project, improving the organizational and technological reliability, and imparting an understanding to the investor / a customer of the resources required for the project implementation.
DOI: 10.22227/1997-0935.2016.10.112-119
Pages 120-130
One of the problems of construction planning is failure to meet time constraints and increase of workflow duration. In the recent years informational technologies are efficiently used to solve the problem of estimation of construction period. The issue of optimal estimate of the duration of construction, taking into account the possible organizational expectations is considered in the article. In order to solve this problem the iteration scheme of evolutionary modeling, in which random values of organizational expectations are used as variable parameters is developed. Adjustable genetic operators are used to improve the efficiency of the search for solutions. The reliability of the proposed approach is illustrated by an example of formation of construction schedules of monolithic foundations for buildings, taking into account possible disruptions of supply of concrete and reinforcement cages. Application of the presented methodology enables automated acquisition of several alternative scheduling of construction in accordance with standard or directive duration. Application of this computational procedure has the prospects of taking into account of construction downtime due to weather, accidents related to construction machinery breakdowns or local emergency collapses of the structures being erected.
DOI: 10.22227/1997-0935.2016.10.120-130
Pages 131-140
In the modern conditions innovatization of construction is of great necessity, though it is associated with a number of problems of first of all institutional genesis. The development of green construction in Russia is on its first stages, though its necessity is growing according to the tendency for energy efficiency and sustainable development. The innovative process of ecological construction has a network model and requires its optimization with the aim of further development by advancing the institutional platform. The author proposed a conceptual scheme for an institutional platform of the innovative process of green construction and conducted systematization of institutional structures. The unique role of innovative and ecological institutes is substantiated. The author recommends an optimization method for institutional interaction of the subjects using the stakeholder theory and the theory of matrix games aimed at activation of innovative green technologies. Practical application of the offered algorithms and methods will allow increasing the efficiency of green construction development.
DOI: 10.22227/1997-0935.2016.10.131-140
Pages 141-150
The author deals with the most widely used methods of risk events identification. The expert response method is most applicable for construction projects using energy efficient technologies. The article presents the results of an opinion poll of the professional expert community using expert response method, which is aimed to identify the most likely potential “pure” risk of construction projects with energy-efficient technologies in use. 74 experts representing different levels of the construction process were polled: customers and directors of construction companies, project managers, risk managers, advisors. The answers were collected during private talks and also using a special website Survey Monkey. Experts from different countries took part: Russia, Great Britain, Austria, Luxemburg, Switzerland and Norway. Also the article presents the expert evaluation of the “effect” of risk implementation on the cost of a project, implementation time, the product quality, the environment and safety on the construction site.
DOI: 10.22227/1997-0935.2016.10.141-150
Pages 151-159
Investment and construction activity as a technical and economic system represents a complex of coordinated elements interdependent in frames of a more complicated structure and logically constituting a whole entity which is controlled basing on control actions stated in a plan. The processes of investment and construction activity are determined by different flows of workforce, raw materials, energy, main funds and investments. On the other hand the system functioning influences these flows. The article presents the structure of investment and construction activity as a technical-and-economic system with large number of input and output flows. For its functioning implementation of strategic control is necessary. The authors consider a suggestion that providing balanced and proportional growth basing on the general aim is the important result of strategy control. Both inner and outer impacts should be taken into account. The higher is the hierarchy level of the investment and construction activity, the higher the degree of complexity of control, management and decision-making functions grow. The formalized description of strategic controlling process is given.
DOI: 10.22227/1997-0935.2016.10.151-159