Neural Network Based Estimation of Service Life of Different Metal Culverts in Arkansas

The Arkansas Department of Transportation (ARDOT) uses different types of metal culverts and cross-drains. Service lives of these culverts are largely influenced by the corrosion of the metals used in these culverts. Corrosion of metallic parts in any soil-water environment is governed by geochemical and electrochemical properties of the soils and waters. Many transportation agencies including ARDOT primarily focus on investigating the physical and mechanical properties of soils rather than their chemical aspects. The main objective of this study is to analyze the geotechnical and geochemical properties of soils in Arkansas to estimate the service lives of different metal pipes in different conditions. Soil resistivity values were predicted after analyzing the United States Department of Agriculture (USDA) soil survey data using neural network (NN) models. The developed NN models were trained and verified by using laboratory test results of soil samples collected from ARDOT, and survey data were obtained from the USDA. The service lives of metal culverts were then estimated based on the predicted soil properties and water quality parameters extracted from the data acquired from the Arkansas Department of Environmental Quality (ADEQ). Finally, Geographic Information System-based corrosion risk maps of three different types of metal pipes were developed based on their estimated service lives. The developed maps will help ARDOT engineers to assess the corrosion potential of the metal pipes before starting the new construction and repair projects and will allow using proper culvert materials to maximize their life spans.

Stress analysis of double-walled pipes undergone mechanical drawing process

Double-walled metal pipes are important components for heat exchange and liquid transportation. They can be manufactured by mechanical drawing of two concentric pipes. In this work, a mechanical model is developed to analyze the stress state evolution during the manufacturing process, and the criterion for forming the double-walled pipe was given under the ideal elastoplastic and thick-walled assumptions. The model also encompasses the results deduced under the thin-walled assumption. Numerical simulations confirmed that the accuracy of the analytical model was within 5%. The application on actual steel materials with various parameters varied, including the wall thickness and initial gap, was analyzed. This work can provide theoretical support to industrial manufacturing procedures and help to reduce costs by eliminating required test procedures.

ANALYSIS OF DESIGN AND CONSTRUCTION OF HYDROTECHNICAL STRUCTURES OF TRANSPORT CONSTRUCTION IN THE FORM OF WATER PIPES MADE OF POLYMER MATTERS

Introduction. The use of modern materials in the road industry is increasingly common in the construction of roads, one of the modern materials is the use of polymer culverts. The analysis of application of plastic culverts on highways is carried out in the work. The general provisions of design and construction of hydraulic structures of transport construction in the form of culverts made of polymeric materials on highways are given. The existing hydraulic calculation, strength calculations of culverts made of polymeric materials on highways are given. Problem statements. From the literature analysis it is established that culverts made of polymeric materials on highways are in difficult operating conditions, which differ from the operating conditions of reinforced concrete and metal pipes. Purpose. Is to study the effectiveness of culverts made of polymeric materials. Results. The analysis of physical and mechanical properties of culverts made of polymeric materials on highways is carried out. Methods of calculation of culverts from polymeric materials on highways are given. As a result of the conducted researches the analysis of efficiency of application of culverts from polymeric materials on highways is executed. On the basis of the conducted researches the basic requirements to culverts from polymeric materials on highways are established. Conclusions. The results of the research were used in the development of a plan of experimental research to improve regulations for the design, construction and repair of culverts made of polymeric materials on highways. The use of polymer pipes will make it possible to make progressive technical solutions for drainage in road projects.

Technical regulation for the values of hydraulic parameters of used metal pipes in order to extend the period of their use

Objective: To compare the characteristics of hydraulic potential in worn steel pipes with internal deposits subjected to cleaning by mechanical and chemical methods. Methods: Calculated dependencies are used for hydraulic calculation of new metal pipes and pipes with internal deposits. Results: A calculated dependence was obtained to determine the value of the inner diameter of pipes with any thickness of the layer of internal deposits. The concept of an efficient pipeline is introduced and a comparison made of the values of head losses in new pipes and in pipes with internal deposits. A specific practical example is considered. For the given example, compare the values of energy consumption of pumping equipment for two methods of cleaning the inner surface of pipes. Measures are indicated to ensure the efficiency of operation of water supply networks. Practical importance: It is shown that the chemical method of technical regulation of the hydraulic characteristics of new steel pipes provides an extension of the period of their further use.

Water Corrosion Problems and Sustainability of Water Supply Schemes

Water supply schemes should be technically and socially sustainable for smooth running, smooth operation and maintenances. Failure in either one of these leads to the whole system failure. Once the system is technically feasible, we can manage its social aspects. In this paper, we deal with technical sustainability of corrosive water, its impacts and the remedial measures. Corrosive water can severely damage intakes, metal pipes, cemented chambers, concrete reservoir and household plumbing systems. Hence, it is necessary to identify the corrosiveness of the water and should be neutralized. There are several solutions to this problem, however, they are not sustainable and economical for semi urban and rural communities. In this paper, we propose a sustainable, natural and economical solution to determine the corrosiveness of water and to effective technology to neutralize it. The proposed solution uses naturally available resources, hence makes it sustainable and affordable. Once the proposed method is deployed, it doesn’t require additional resources such as continuous monitoring, skilled manpower and electrical power cost etc. In this method, initially, the corrosiveness of the water is identified using parameters such as: total dissolved solid (TDS), pH, temperature, calcium and alkalinity. The corrosive water is then analyzed in laboratory. With carbon dioxide kinetic study, we verify the design of stabilization tank volume calculation. The research outcome is applied in the field to upgrade intake, pipe and fitting designs. The experiment in this research is conducted with the data obtained from several water supply schemes including Padampokhari water supply scheme in Nepal and tested in the same water supply scheme.

Silver-Derived Antimicrobial Coatings for the Prevention of Microbial Biofilms in Metal Pipes

Biodeterioration is one of the most important processes in metal pipeline corrosion, and it can be due to physical, chemical, and biological factors. Coatings rich in silver have been used to inhibit this undesirable phenomenon. In this study, the antimicrobial properties of several silver-containing products used as a coating in pipelines were determined on a pilot scale in order to evaluate the ability of silver to inhibit biofilm formation. The results showed that the coating with silver zeolite at a concentration of 2000 mg L–1 inhibited the formation of a microbial biofilm and prevented the biodeterioration process. Therefore, from our study, it can be concluded that silver zeolite shows greater protection capacity than other silver preparations and presents advantages in relation to other silver coatings that are currently available

ENERGY SAVING TECHNOLOGIES IN THE IMPLEMENTATION OF CATHODIC PROTECTION OF PIPELINES AND TANKS

The data on the introduction of new energy-saving technologies of cathodic protection – the installation of magnetite ground electrodes, the use of new activators based on coke breeze, a pulse converter for automatic control of cathodic protection objects are considered. Practical results show that the use of magnetite anodes allows maintaining a high permissible current density, therefore, it is suitable for widespread use in various soils and seawater. The rate of dissolution of magnetite is 0.02 kg / (A • year). Magnetite anodes are also successfully used for the repair of GAZ wells (deep earthing conductors made of metal pipes). To perform this type of work, a typical project has been developed, which allows restoring the operability of deep anode grounding with minimal costs and without the use of expensive drilling operations. The use of activated coke breeze significantly reduces the transition resistance of the anode grounding. It has been practically proven that when using a coke-mineral activator, the transition resistance is significantly reduced due to an increase in the electrical conductivity of the filler at the anode space, the geometric dimensions and current of the diverting object increase, and the transition resistance of the anode - ground is stabilized. LLC "Elmet" has developed a pulse converter of automatic control IPAU designed to convert alternating current into rectified direct current with the possibility of automatic adjustments in several parameters. The basis of the converters is a high-frequency transistor inverter, developed on the basis of the latest achievements in power electronics. The use of stations of the IPAU type with telemetry allows to reduce labor costs for their maintenance in accordance with clause R.6.1 DSTU B V.2.5-29: 2006 Gas supply system. Underground steel gas pipelines and p. 8.9 of DSTU 4219: 2003 Steel main pipelines, which will make it possible to use the freed up personnel in other areas.

Stress analysis of double-walled pipes undergone mechanical drawing process

Double-walled metal pipes are important components for heat exchange and liquid transportation. They can be manufactured by mechanical drawing of two concentric pipes. In this work, a mechanical model is developed to analyze the stress state evolution during the manufacturing process, and the criterion for forming the double-walled pipe was given under the ideal elastoplastic and thick-wall assumptions. The model also encompasses the results deduced under the thin-wall assumption. Numerical simulations confirmed that the accuracy of the analytical model was within 5%. The application on actual steel materials with various parameters varied, including the wall thickness and initial gap, was analyzed. This work can provide theoretical support to industrial manufacturing procedures and help to reduce costs by eliminating required test procedures.