scholarly journals SOME NEW TECHNOLOGIES IN ROAD CONSTRUCTION

2020 ◽  
Vol 3 (1) ◽  
pp. 62-69 ◽  
Author(s):  
I. Odenbah

this article discusses some new modern technologies in the construction of highways. The paper analyzes the use of such innovations as: various modifiers added to bitumen; advanced technologies of engineering surveys and computer-aided design of highways; geosynthetic materials for reinforcing the roadbed and asphalt concrete pavement; PBB; bituminous polymer road belts; geotextile; foam-glass rubble; rubber crumb. The advantages of using innovations in road construction are highlighted. Obstacles to the use of certain technologies are noted, taking into account the Russian reality. The author concludes that the use of innovative materials becomes economically justified at the stage of construction and subsequent operation of the road surface. New technologies can not only improve the quality of roads, but also improve road safety. Innovations lead to progressive changes and ensure the dynamic development of the construction industry, primarily by reducing the cost and timing of construction, improving the quality of constructed facilities, and improving the comfort of living and operation. The paper discusses classical methods for the design works of the foundation and the GM made a review of modern structures and technologies on their device. In order to assess the possibility of using linear calculation for sheet piling fences, deep pit modeling was performed in the SCAD and PLAXIS software systems. The results of the work are the following conclusions: 1. the method of increasing the efficiency of technologies at the device walling of the pit is proposed; 2. a finite element model of soil and GM collaboration was created. To evaluate the effectiveness of the options, we used decision-making methods based on optimization criteria, taking into account the degree of risks involved in the work. It is established that the necessary factor is the geotechnical support of technological impacts, which allows monitoring of works on the degree of safety and impact on highways.

2021 ◽  
Vol 2021 (23) ◽  
pp. 31-42
Author(s):  
Anatolii Tsynka ◽  
◽  
Andrii Hrinchuk ◽  
Ivan Rakovych ◽  
◽  
...  

Introduction. In the modern conditions of the pricing system in the construction of Ukraine, the key value have the estimated norms, which are presented in separate collections, the main purpose of which is to determine the standard quantity of resources required to perform a particular type of work as a basis for the transition to the cost indicators. In order to determine the cost of road work objectively and accurately, it is essential that the indicators of estimated norms meet the requirements of regulatory documents and modern methods of execution of road works.Problematics. In connection with the active improvement of the regulatory base of the road construction industry, permanent upgrade of road organizations technique fleet, the introduction of new technologies and materials in construction and operation of roads, improving the methods of work there is a discrepancy between the existing resource element of estimated norms and the actual conditions of work in terms of built-up labor costs, the operation time of machines and mechanisms and the range of materials. Accordingly, it affects the reliability and accuracy of determining the cost of road works.Purpose. Improvement and harmonization with actual working conditions and requirements of regulatory documents of industry regulatory and estimate base of resource elementary estimated norms for work performed during construction, reconstruction, repair and operational maintenance of roads and bridges to ensure reliable and valid technical, economic and estimated calculations.Materials and methods. During work performance the analysis of the regulatory documentation, establishing the requirements to the technology of road works and materials has been carried out. A number of chronometric observations with the measurement of time of road works in full-scale conditions was carried out. The obtained data were summarized, averaged and on their basis the indicators of the resource element of the estimated norms were estimated.Results. A review of the main amendments and additions, which came into force after the approval of Amendment No 2 SOU 42.1-37641918-035:2018 [1] and Amendment No 2 SOU 42.1-37641918-071:2018 [2], which were developed to improve the regulatory-estimate base for the calculation of road works, taking into account the requirements and provisions of existing regulatory documents taking into account the current state of scientific and technological progress in the road sector.Conclusions. The above analysis of the amendments that came into force with the approval of [1]. and [2] will systematize the innovations provided by the requirements of current regulatory documents on the calculation of the cost of road works and the development of relevant documents at all stages of the investment process, planning and organization of road works, as well as the writing-off of material resources. Review and systematization of recent improvements in the estimated regulatory documents for road works will provide an opportunity to optimally plan the use of available material, labor and financial resources, often limited.Keywords: public road, operational maintenance, investment documentation, overhaul and current repairs, machine, mechanism, regulatory document, resource element estimate norm, Standard of Organization of Ukraine.


Author(s):  
Tapoglou Nikolaos ◽  
Antoniadis Aristomenis

Gear hobbing is a common method of manufacturing high precision involute gears. The thorough knowledge of the developed cutting forces and the wear of the cutting tool are of great importance in order to produce helical and spur gears as they influence the cost of the manufacturing process and the quality of the produced gear. A novel simulation code called HOB3D was created in accordance with the above. This code can simulate the complex movements involved in gear hobbing with the best available accuracy, which is achieved by embedding the developed algorithm in a commercial computer aided design (CAD) environment. The simulation code calculates and exports the total cutting forces as well as the cutting forces in every cutting edge involved in the cutting process.


Author(s):  
Saed Amer ◽  
Landon Onyebueke

The concerns of comfortable seat grew more momentous as this era brought new technologies leading to nonstop flights and more dependence on computers; hence, individuals spend more time seated to perform everyday activities. Uncomfortable prolonged sitting may reduce the quality of such activities and may yield health implications. Seat comfort evaluations are conventionally done post-production i.e. a fully produced seat is usually required in order to evaluate its level of comfort. Also, the inputs from the customer which could have significant impression on the comfort level of the seat are usually not considered during the design stages. This study proposes a solution with a system that performs seat comfort design and evaluation by integrating a Quality Function Deployment (QFD) tool with Computer Aided Design (CAD) technique. Several laboratory tests were performed to validate the proposed technique and the obtained results verify that the system can be a valid tool that can surrogate the traditional techniques for comfort analyses. The proposed system offers a comprehensive and systematic tool for the design and prediction of seat comfort by integrating the voice of the customer via QFD into CAD. Taking everything into account, the proposed system will diminish the need for physical prototyping, limit the involvement of human subjects and facilitate information sharing.


2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Andrey Kochetkov ◽  
Natal’ya Shchegoleva ◽  
Sergey Korotkovskiy ◽  
Victor Talalai ◽  
Yury Vasilyev ◽  
...  

The implementation of the proposed innovative project on the use of phosphogypsum waste in road construction will: solve the problem of recycling and processing of phosphogypsum by using it as a local by-material for the construction of roadbed and foundations of roads; replace natural gypsum with cheaper raw materials for cement, construction and road industry; reduce the cost of construction of roads and extend the turnaround time by improving the quality of their properties. Road with the use of phosphogypsum is cheaper by 30 % than roads with traditional technologies. In the swampy area due to the characteristics of the material, combining solidity and lightness, phosphogypsum is not interchangeable at all. It allows you to make reliable and durable roads. The design is obtained up to five times stronger than the required standards. At the same time, at the first stage of construction of the road, it is possible to make an intermediate type, making the bases of phosphogypsum, and later laying the remaining structural layers of crushed stone and asphalt. In this case, the coating of technical gypsum is not destroyed, even with the passage of heavy tracked vehicles and at low temperatures.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Kristýna Hynková ◽  
Iva Voborná ◽  
Bernard Linke ◽  
Liran Levin

Abstract Nowadays, patients require the highest quality of treatment, but generally prefer to spend as little time as possible in the dental chair. Therefore, there is significant benefit for using new technologies such as CAD/CAM (computer aided design/computer aided manufacturing), which provides both quality and speed. There is an increase in ceramic materials and ceramic blocks/discs available, with varying properties. This has resulted in some confusion and difficulty in making an informed decision about which material is best for a specific clinical situation. The objective of this review is to provide an overview and comparison of basic mechanical properties of currently used CAD/CAM ceramic materials based on a review of the currently available literature.


The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.


Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1401
Author(s):  
Doo-Bin Song ◽  
Man-So Han ◽  
Si-Chul Kim ◽  
Junyong Ahn ◽  
Yong-Woon Im ◽  
...  

This study investigated the fitting accuracy of titanium alloy fixed dental prostheses (FDP) after sequential CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) fabrication. A three-unit FDP model connecting mandibular second premolars and molars was prepared and scanned to fabricate titanium FDPs by CAD/CAM milling. A total of six FDPs were sequentially milled in one titanium alloy disk using a new set of burs every time (n = 4). The fitting accuracy of FDPs was mesiodistally evaluated by a silicone replica technique and the measurement was triplicated at four different locations: MO (marginal opening), MG (marginal gap), AG (axial gap), and OG (occlusal gap). Data were statistically analyzed using ANOVA and Tukey’s HSD test. The fitting accuracy of PMMA (polymethyl methacrylate) FDPs milled using the worn or new bur were evaluated by the same procedure (n = 6). The mean dimensions of titanium FDP for all measuring positions, except for AG, were significantly increased from the third milling. However, no difference was noted between the first FDP and the second FDP milled with the same set of burs. Severe edge chippings were observed in all milling burs. Detrimental effects of the worn burs on the fitting accuracy were demonstrated in the CAD/CAM-milled PMMA FDP. The results recommend proper changing frequency of cutting burs to achieve the quality of fit and predictable outcomes for dental CAD/CAM prostheses.


2021 ◽  
Vol 26 (5) ◽  
pp. 399-409
Author(s):  
M.A. Zapletina ◽  
◽  
S.V. Gavrilov ◽  
◽  

One of the main advantages of FPGA and CPLD is the high development speed; therefore, the importance of effective computer-aided design tools for modern microcircuits of these classes cannot be overestimated. Placement and routing are the most time-consuming stages of FPGA/CPLD design flow. The quality of results of these stages is crucial to the final perfor-mance of custom digital circuits implemented on FPGA/CPLD. The paper discusses an approach to accelerating the routing stage within the layout synthesis flow for FPGA/CPLD by introducing a few algorithmic improvements to a routing procedure. The basic routing algorithm under study is a modified Pathfinder for a mixed routing resource graph. Pathfinder is a well-known negotiation-based routing algorithm that works on the principle of iteratively eliminating congestions of chip routing resources. For experiments, the sets of test digital circuits ISCAS'85, ISCAS'89, LGSynth'89 and several custom industrial projects were used. The impact of the proposed algorithmic improvements was analyzed using four FPGA/CPLD architectures. It has been established that due to the improvements of the algorithm proposed in the paper, the average reduction in routing time was from 1.3 to 2.6 times, depending on the FPGA/CPLD architecture, with no significant negative effect on the timing characteristics of the designed circuits.


2021 ◽  
Vol 6 (2) ◽  
pp. 70-77
Author(s):  
Ari Siswanto ◽  
◽  
Ira Kusumawaty ◽  

Water functions are very diverse for humans for daily needs such as drinking water, bathing, agriculture, development, aesthetics, and lower temperatures. Palembang is a lowland area dominated by wetlands, tidal swamps, and rivers. The types of houses on stilts on the banks of the Musi river are limas, Gudang, and Chinese stilt houses which are always associated with the water environment. The construction of roads replacing the role of rivers has realized people that the water environment has an important meaning for the house on stilts. The research objective was to explore the meaning of the water environment from various aspects for residents, stilt houses, and their environment. This research method is a case study with data collection through interviews, observation, measurements, and taking photos. Data and findings were analyzed and juxtaposed with images in the field. The road construction has eliminated part of the function of the river and influenced the change in orientation of the house on stilts. In conclusion, respect for the water environment including rivers has decreased, causing the quality of the river to decline, and the house on stilts cannot take advantage of the existence of the water environment optimally


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