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

2021 ◽  
Vol 2021 (24) ◽  
pp. 112-133
Author(s):  
Artur Onyshchenko ◽  
◽  
Mykola Garkusha ◽  
Mykola Klymenko ◽  
◽  
...  

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.

Author(s):  
Alok Bhowmick ◽  
Sanjay Jain

<p>India’s transport sector is large and diverse; it caters to the needs of 1.25 billion people. Roads are the dominant mode of transportation in India today. They carry almost 90 percent of the country’s passenger traffic and 65 percent of its freight. Cognizant of the need to create an adequate road network to cater to the increased traffic and movement of goods, Government of India has recently allotted Rs 640 billion (US$ 9.55 billion) to National Highway Authority of India (NHAI) for roads and highways and Rs 270 billion (US$ 4.03 billion) for rural roads under PMGSY scheme (as on 20th April 2017). One of the impediment in the fast progress of road infrastructure is acquisition of land &amp; related regulatory hurdles. Completion of as many as 112 projects of NHAI is delayed on account of such factors. There is a restriction of the available width and to spread the road horizontally. Therefore, present trend in urban areas is to go for elevated grade separators, wherein both surface level as well as elevated road can be fully utilised for traffic movement. By avoiding costly land acquisition, it results in reduction in cost of the project and certainly segregate local and fast moving traffic, thereby further increasing speed of movement. Design and Construction of such elevated corridors however poses many challenges to structural engineers. Restricted work space during construction adds to the challenge and brings out many innovative solutions to the problems. This paper discusses case studies of number of such projects for which the authors are presently associated in design and construction planning. These projects are in various stages of construction.</p>


2014 ◽  
Vol 42 (1) ◽  
pp. 2-15
Author(s):  
Johannes Gültlinger ◽  
Frank Gauterin ◽  
Christian Brandau ◽  
Jan Schlittenhard ◽  
Burkhard Wies

ABSTRACT The use of studded tires has been a subject of controversy from the time they came into market. While studded tires contribute to traffic safety under severe winter conditions by increasing tire friction on icy roads, they also cause damage to the road surface when running on bare roads. Consequently, one of the main challenges in studded tire development is to reduce road wear while still ensuring a good grip on ice. Therefore, a research project was initiated to gain understanding about the mechanisms and influencing parameters involved in road wear by studded tires. A test method using the institute's internal drum test bench was developed. Furthermore, mechanisms causing road wear by studded tires were derived from basic analytical models. These mechanisms were used to identify the main parameters influencing road wear by studded tires. Using experimental results obtained with the test method developed, the expected influences were verified. Vehicle driving speed and stud mass were found to be major factors influencing road wear. This can be explained by the stud impact as a dominant mechanism. By means of the test method presented, quantified and comparable data for road wear caused by studded tires under controllable conditions can be obtained. The mechanisms allow predicting the influence of tire construction and variable operating conditions on road wear.


Author(s):  
Badal Dev Roy ◽  
R. Saravanan

The Turbocharger is a charge booster for internal combustion engines to ensure best engine performance at all speeds and road conditions especially at the higher load.  Random selection of turbocharger may lead to negative effects like surge and choke in the breathing of the engine. Appropriate selection or match of the turbocharger (Turbomatching) is a tedious task and expensive. But perfect match gives many distinguished advantages and it is a one time task per the engine kind. This study focuses to match the turbocharger to desired engine by simulation and on road test. The objective of work is to find the appropriateness of matching of turbochargers with trim 67 (B60J67), trim 68 (B60J68),  trim 70 (A58N70) and trim 72 (A58N72) for the TATA 497 TCIC -BS III engine. In the road-test (data-logger method) the road routes like highway and slope up were considered for evaluation. The operating conditions with respect various speeds, routes and simulated outputs were compared with the help of compressor map.


2020 ◽  
pp. 39-48
Author(s):  
B. O. Bolshakov ◽  
◽  
R. F. Galiakbarov ◽  
A. M. Smyslov ◽  
◽  
...  

The results of the research of structure and properties of a composite compact from 13 Cr – 2 Мо and BN powders depending on the concentration of boron nitride are provided. It is shown that adding boron nitride in an amount of more than 2% by weight of the charge mixture leads to the formation of extended grain boundary porosity and finely dispersed BN layers in the structure, which provides a high level of wearing properties of the material. The effect of boron nitride concentration on physical and mechanical properties is determined. It was found that the introduction of a small amount of BN (up to 2 % by weight) into the compacts leads to an increase in plasticity, bending strength, and toughness by reducing the friction forces between the metal powder particles during pressing and a more complete grain boundary diffusion process during sintering. The formation of a regulated structure-phase composition of powder compacts of 13 Cr – 2 Mо – BN when the content of boron nitride changes in them allows us to provide the specified physical and mechanical properties in a wide range. The obtained results of studies of the physical and mechanical characteristics of the developed material allow us to reasonably choose the necessary composition of the powder compact for sealing structures of the flow part of steam turbines, depending on their operating conditions.


2020 ◽  
Vol 27 (10) ◽  
pp. 1616-1633 ◽  
Author(s):  
Oana Cristina Duta ◽  
Aurel Mihail Ţîţu ◽  
Alexandru Marin ◽  
Anton Ficai ◽  
Denisa Ficai ◽  
...  

Polymeric materials, due to their excellent physicochemical properties and versatility found applicability in multiples areas, including biomaterials used in tissue regeneration, prosthetics (hip, artificial valves), medical devices, controlled drug delivery systems, etc. Medical devices and their applications are very important in modern medicine and the need to develop new materials with improved properties or to improve the existent materials is increasing every day. Numerous reasearches are activated in this domain in order to obtain materials/surfaces that does not have drawbacks such as structural failure, calcifications, infections or thrombosis. One of the most used material is poly(vinylchloride) (PVC) due to its unique properties, availability and low cost. The most common method used for obtaining tubular devices that meet the requirements of medical use is the surface modification of polymers without changing their physical and mechanical properties, in bulk. PVC is a hydrophobic polymer and therefore many research studies were conducted in order to increase the hydrophilicity of the surface by chemical modification in order to improve biocompatibility, to enhance wettability, reduce friction or to make lubricious or antimicrobial coatings. Surface modification of PVC can be achieved by several strategies, in only one step or, in some cases, in two or more steps by applying several techniques consecutively to obtain the desired modification / performances. The most common processes used for modifying the surface of PVC devices are: plasma treatment, corona discharge, chemical grafting, electric discharge, vapour deposition of metals, flame treatment, direct chemical modification (oxidation, hydrolysis, etc.) or even some physical modification of the roughness of the surface.


Author(s):  
Shaosen Ma ◽  
Guangping Huang ◽  
Khaled Obaia ◽  
Soon Won Moon ◽  
Wei Victor Liu

The objective of this study is to investigate the hysteresis loss of ultra-large off-the-road (OTR) tire rubber compounds based on typical operating conditions at mine sites. Cyclic tensile tests were conducted on tread and sidewall compounds at six strain levels ranging from 10% to 100%, eight strain rates from 10% to 500% s−1 and 14 rubber temperatures from −30°C to 100°C. The test results showed that a large strain level (e.g. 100%) increased the hysteresis loss of tire rubber compounds considerably. Hysteresis loss of tire rubber compounds increased with a rise of strain rates, and the increasing rates became greater at large strain levels (e.g. 100%). Moreover, a rise of rubber temperatures caused a decrease in hysteresis loss; however, the decrease became less significant when the rubber temperatures were above 10°C. Compared with tread compounds, sidewall compounds showed greater hysteresis loss values and more rapid increases in hysteresis loss with the rising strain rate.


Author(s):  
K.O. Kobzev ◽  
◽  
S.A. Vyalov ◽  
E.S. Bozhko ◽  
I.A. Zolotuhina ◽  
...  

This article deals with the problem of operating conditions of guide moving crossbars of hydraulic presses. Based on the study of hydraulic press operation processes, the need to develop and implement measures to ensure reliable and trouble-free operation of the press was identified. The conclusion justifies the idea that if these technical solutions are implemented, the service life of hydraulic presses will increase


2021 ◽  
Vol 18 (3) ◽  
pp. 421-427
Author(s):  
Oleg A. PRODOUS ◽  
◽  
Lev D. TEREKHOV ◽  
Petr P. YAKUBCHIK ◽  
Alexander S. CHERNIKH ◽  
...  

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.


2018 ◽  
Vol 19 (1-2) ◽  
pp. 69-92 ◽  
Author(s):  
Carlos Oliveira Cruz ◽  
Joaquim Miranda Sarmento

Roads are a central element of transportation systems, enabling economic and social development, fostering territorial cohesion and facilitating the movement of people and cargo. Governments have devoted significant financial resources to developing and improving their road networks, and are still facing increasing pressure to ensure proper maintenance and payments to those concessionaires that developed roads under public–private partnership arrangements. As in other sectors, digitalization is paving a way towards significant changes in the way we build, operate and finance infrastructure. These changes will have a profound impact on the entire life cycle of an infrastructure, from the design and/or construction stage, to its operation and transfer. This article provides an overall overview of the main technological developments which are, or could impact road infrastructure in the short, medium and long term. For each technological development identified in our research, we analyse the potential impact on Capex, Opex and revenues as well as their level of maturity and expected lifetime for mass adoption, and also the main bottlenecks or barriers to implementation. Additionally, we explore potential savings on investment (capex) and operational costs (opex) and increase in revenues, using data from the Portuguese highway companies. Savings can represent almost 30% of capex and opex. Overall, savings and increases in revenues can represent an impact similar to 20–40% of current revenues. The findings show that digitalization and technological development in the road sector can significantly impact the economic performance of roads, thus enhancing the value of money for the society. The findings also show that there might be some excess capacity of road systems once autonomous vehicles achieve higher market penetration. However, there are still some relevant legal, regulatory, institutional and technological and economic barriers that are slowing down the digitalization process.


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