DESIGNING STRUCTURES OF RIGID ROAD CLOTHING WITH THE APPLICATION OF METALLURGICAL BY-PRODUCTS INDUSTRY FOR DISTRIBUTION R OADS OF REGIONAL SIGNIFICANCE

Author(s):  
А. В. Еремин ◽  
О. А. Волокитина ◽  
Н. Ю. Алимова

Постановка задачи. Разработать рецептуры шлаковых асфальтобетонных смесей с оптимальным содержанием битума, исследовать их физико-механические свойства и на основании полученных результатов выявить преимущества и обосновать комплексное применение отходов металлургической промышленности на стадии проектирования конструкций дорожных одежд. Результаты. Проведены испытания образцов материалов конструктивных слоев в лабораторных условиях, дана оценка физико-механическим и прочностным характеристикам на основе определения фактического модуля упругости путем послойного измерения прогибов дорожной одежды на экспериментальном участке. Выводы. Полученные результаты исследований свидетельствуют о возможности применения шлаковых материалов в составе различных слоев нежесткой дорожной одежды на стадии проектирования конструкции. Выявлены преимущества использования шлаковых материалов в процессе строительства автомобильных дорог за счет сокращения затрат на материалы и в процессе эксплуатации с позиции безопасности и экологичности. Problem statement. To develop formulations of slag asphalt concrete mixtures with an optimal bitumen content, to study their physical and mechanical properties, and, on the basis of the results obtained, to identify the advantages and substantiate the integrated use of metallurgical industry waste at the stage of designing pavement structures. Results. The tests of samples of materials of structural layers in laboratory conditions were carried out, an assessment of the physical-mechanical and strength characteristics was given based on the determination of the actual modulus of elasticity by layer-by-layer measurement of the deflections of the pavement in the experimental section. Conclusions. The obtained research results indicate the possibility of using slag materials in the composition of various layers of non-rigid pavement at the design stage of the structure. The advantages of using slag materials in the process of building highways by reducing the cost of materials and in the process of operation from the standpoint of safety and environmental friendliness are revealed.

2021 ◽  
Vol 4 (1) ◽  
pp. 9
Author(s):  
Vera Mahardika ◽  
Rachmat Mudiyono ◽  
Soedarsono Soedarsono

Flexible, rigid, and paving block pavements can be used as alternative roads because the soil conditions on the Pantai Utara Flores road are rocky soil with a relatively high CBR so that the most important role in withstand load is subgrade. The purpose of the Comparison of Construction and Costs for Flexible, Rigid, and Paving Block Pavement Structures on Jalan Pantai Utara Flores is to know which one most effective and efficient when viewed from the traffic load  with each  pavement using the Bina Marga method, AASHTO , and Direktorat Jendral Bina Marga. Jalan Pantai Utara Flores is access to Komodo Labuan Bajo airport which is a Class I road, rocky land with a relatively high CBR, rainfall of Labuan Bajo is relatively low, LHR in Labuan Bajo is relatively small, besides Labuan Bajo is a tourist area that should be supported  by road access that has driving comfort so the suitable pavement structure for Jalan Pantai Utara Flores is flexible pavement. Meanwhile, based on the recapitulation of the analysis results, the cost of flexible pavement is Rp. 28,793,604,705,600, the cost of a rigid pavement  is Rp. 34,218,430,585,828 and  the cost of paving block pavement  is Rp. 17,410,645,080,000 so it can be seen that the paving block pavement is most economical, but the paving block pavement structure has a very uncomfortable driving comfort besides that the paving block pavement structure cannot be passed by vehicles at high speed so that the paving block pavement structure is more suitable for controlling speed of vehicles such as roads in crowded urban areas and residential roads.


Author(s):  
I. V. Cheremukhina

The modern production of products made of composite materials based on thermosetting binders is mainly based on the use of pre – impregnated reinforcing technical threads-prepregs. The binder used for such semi-finished products must meet two important technological requirements: have a low reactivity (high viability) when stored in the temperature range from -5 to +25 ° C and the ability to adjust the curing time at the molding temperatures of the product. To eliminate the disadvantages of the traditional method of obtaining polymer composite materials, to improve their strength characteristics and reduce the cost of the resulting reinforced composites, it is proposed to use the method of layered application of components. The essence of the method consists in layer-by-layer impregnation of the fibrous filler with a binder solution, and then a developed curing system consisting of an amine hardener that prevents the interaction of the hardener with the resin under storage conditions and protective polymer emulsions. The binder-filler system is activated only at an elevated temperature under curing conditions. It is established that the optimal parameters for processing by direct pressing of the pre-pegs components obtained by the method of layer deposition are a pressure of 15 MPa and a temperature of160-170 ?С with a pressure exposure of 15 minutes. If you get products by winding, then for such products, heat treatment for 6 hours at a temperature of 120 ?С is optimal. In the conditions of forming products, that is, at an elevated temperature and at an increased pressure, the mutual diffusion of components occurs due to the movement of oncoming flows. Oligomeric molecules from the resin volume diffuse from the inner layer to the outer one, and the components of the curing system meet them from the outer layer to the inner one. The method of layered application of components makes it possible to create a macroheterogenic system of interpenetrating polymer meshes in the contact area of sequentially applied layers. The result of the research is an increase in the shelf life, the viability of prepregs (up to 10 days) and an improvement in the complex of physical and mechanical properties of composites: the destructive stress during static bending increases to 60 %, during dynamic bending (impact) - up to 50 %. The use of carboxymethylcellulose as a protective polymer provides higher indicators of the studied properties than when using butadiene styrene latex as a protective polymer..


2021 ◽  
Vol 1 ◽  
pp. 131-140
Author(s):  
Federica Cappelletti ◽  
Marta Rossi ◽  
Michele Germani ◽  
Mohammad Shadman Hanif

AbstractDe-manufacturing and re-manufacturing are fundamental technical solutions to efficiently recover value from post-use products. Disassembly in one of the most complex activities in de-manufacturing because i) the more manual it is the higher is its cost, ii) disassembly times are variable due to uncertainty of conditions of products reaching their EoL, and iii) because it is necessary to know which components to disassemble to balance the cost of disassembly. The paper proposes a methodology that finds ways of applications: it can be applied at the design stage to detect space for product design improvements, and it also represents a baseline from organizations approaching de-manufacturing for the first time. The methodology consists of four main steps, in which firstly targets components are identified, according to their environmental impact; secondly their disassembly sequence is qualitatively evaluated, and successively it is quantitatively determined via disassembly times, predicting also the status of the component at their End of Life. The aim of the methodology is reached at the fourth phase when alternative, eco-friendlier End of Life strategies are proposed, verified, and chosen.


Coatings ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 74
Author(s):  
Hatem Alhazmi ◽  
Syyed Adnan Raheel Shah ◽  
Muhammad Aamir Basheer

Rigid pavement structures are one of the costly components of the infrastructure development process. It consumes a huge quantity of ingredients necessary for concrete development. Hence, a newly introduced concept of circular economy in combination with waste management was introduced to solve this problem. In this study, three waste products (rice husk ash (RHA), wood sawdust (WSD), and processes waste tea (PWT)) was utilized to develop the concrete for rigid pavement structures by replacing the sand, i.e., a filler material at different percentages. During the testing procedure of compressive (CS), tensile (TS), and flexural strength (FS) properties, RHA and WSD at 5% replacement were found to be a good replacement of sand to develop required concrete. This study will help in the production of eco-friendly rigid pavement structures and a pathway of life cycle assessment in the future.


Healthcare ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 888
Author(s):  
Leopoldo Sdino ◽  
Andrea Brambilla ◽  
Marta Dell’Ovo ◽  
Benedetta Sdino ◽  
Stefano Capolongo

The need for 24/7 operation, and the increasing requests of high-quality healthcare services contribute to framing healthcare facilities as a complex topic, also due to the changing and challenging environment and huge impact on the community. Due to its complexity, it is difficult to properly estimate the construction cost in a preliminary phase where easy-to-use parameters are often necessary. Therefore, this paper aims to provide an overview of the issue with reference to the Italian context and proposes an estimation framework for analyzing hospital facilities’ construction cost. First, contributions from literature reviews and 14 case studies were analyzed to identify specific cost components. Then, a questionnaire was administered to construction companies and experts in the field to obtain data coming from practical and real cases. The results obtained from all of the contributions are an overview of the construction cost components. Starting from the data collected and analyzed, a preliminary estimation tool is proposed to identify the minimum and maximum variation in the cost when programming the construction of a hospital, starting from the feasibility phase or the early design stage. The framework involves different factors, such as the number of beds, complexity, typology, localization, technology degree and the type of maintenance and management techniques. This study explores the several elements that compose the cost of a hospital facility and highlights future developments including maintenance and management costs during hospital facilities’ lifecycle.


2012 ◽  
Vol 594-597 ◽  
pp. 1445-1448
Author(s):  
Tao Cheng ◽  
Ke Qin Yan

Mechanics properties of lime- fly ash stabilized soil are investigated. First, the chemical composition of fly ash are analyzed by spectral analysis test. Compaction experiments of all mix proportion projects are carried out in different water conditions to obtain the optimum water contents. Then the optimum mix proportion is obtained by the unconfined compressive strength and the compression rebound modulus test. Finally, the pavement structures design for a highway of lime- fly ash stabilized soil road sub-base is done. By the comparison, a conclusion can be drawn that lime-fly ash stabilized soil is suitable for flexible pavement or semi-rigid pavement because of its good strength and rigidity which can effectively reduce thickness of the lower pavement and basic deflection.


Author(s):  
Shonit Nair Sharma ◽  
Devrina Chidambaram ◽  
Gianna Mizzi ◽  
Daniel Rosen ◽  
Kristin Slaughter ◽  
...  

Abstract As a preemptive response to the widespread need for respiratory medical devices developing in the wake of the COVID-19 pandemic, we propose a low-cost incentive spirometer for respiratory rehabilitation in patients with reduced lung function. An incentive spirometer manufactured entirely out of recyclable material, termed “Paperometer,” aims to address the multifaced problem of medical device inaccessibility: high cost, lack of user- or environmental-friendliness, and unavailability to those who need them the most. Operating in accordance with governing physical formulae including Ohm’s law and the Hagen-Poiseuille equation, Paperometer is intended to improve the user’s lung function through repeated use of the device, which facilitates slow, deep breaths of air. Several prototypes were created based on a list of design criteria established through background research and stakeholder interviews. From four initial prototypes, all created predominantly from simple foldable geometries, one design was selected for further iteration. The most promising functional prototype was crafted from recyclable plastic and paper folded into various shapes including a box, tube, and pinwheel. The Paperometer concept stands as an innovative solution to reduce the cost and environmental burden of meeting the demand for medical devices. Once validated, the device may serve as an important tool in combating the ongoing global pandemic.


2014 ◽  
Vol 48 (1) ◽  
pp. 104-109 ◽  
Author(s):  
Áquila Lopes Gouvêa ◽  
Antônio Fernandes Costa Lima

Quantitative research that aimed to identify the mean total cost (MTC) of connecting, maintaining and disconnecting patient-controlled analgesia pump (PCA) in the management of pain. The non-probabilistic sample corresponded to the observation of 81 procedures in 17 units of the Central Institute of the Clinics Hospital, Faculty of Medicine, University of Sao Paulo. We calculated the MTC multiplying by the time spent by nurses at a unit cost of direct labor, adding the cost of materials and medications/solutions. The MTC of connecting was R$ 107.91; maintenance R$ 110.55 and disconnecting R$ 4.94. The results found will subsidize discussions about the need to transfer money from the Unified Health System to hospitals units that perform this technique of analgesic therapy and it will contribute to the cost management aimed at making efficient and effective decision-making in the allocation of available resources.


2020 ◽  
Vol 4 (157) ◽  
pp. 7-11
Author(s):  
V. Zhvan ◽  
V. Donenko ◽  
S. Kulish ◽  
A. Taran

The article is devoted to the effective analysis of trench and trenchless pipeline laying technologies. In the course of the work, an analytical review of pipeline assembly was performed, the main technological parameters, the scope of each method, and their advantages and disadvantages were determined. List of considered pipeline laying methods: trenching, horizontal directional drilling, mechanical puncture, hydraulic puncture, microtunneling and punching. The article analyzes the classical trench method and the most widely used trenchless ones: horizontal directional drilling; mechanical puncture; hydraulic puncture; microtunneling; punching. Each of these methods has several advantages and disadvantages. The choice of the optimal method of laying the pipeline depends on many factors: the physical and mechanical properties of soils and hydrogeological conditions, the length and diameter of the pipeline, the presence of other communications, buildings and structures, as well as the budget that customers have. Work time is the last deciding factor. Based on the results of the analysis of pipeline laying technologies and expert survey of construction industry experts, the cost table of each method was compiled, outlining the main characteristics of the technology: length of pipeline, speed of work, scope, cost, and the advantages and disadvantages of each of the considered methods. The conclusions about the use of each of the pipeline laying methods were made. Each of the methods has its advantages and disadvantages, so to choose the method of work it is necessary to conduct a comprehensive assessment of technological parameters, cost, scope and timing of work. The cost of lay-ing the pipeline consists of the following factors: conducting research; selection of diameter and determination of pipeline length; choice of laying method and equipment necessary for the works; selection of equipment, shut-off and control equipment and other materials arranged on the pipeline; terms of performance of works. Taking into account these factors, an estimate is made, which determines the cost of installation of a particular pipeline. After the analysis, we can conclude that among the methods of trenchless laying of pipelines can be identi-fied horizontally directional drilling, it is this method of laying the pipeline will be appropriate to use for our region. The drilling technique allows to carry out pipelines under obstacles, to pull long segments of networks, to repair site damage. This method is universal and can be used in almost any environment. Keywords: trenches, horizontal directional drilling, mechanical puncture, hydraulic piercing, microtunnelling, punching, pipeline.


Author(s):  
O. V. Karmanova ◽  
S. G. Tikhomirov ◽  
E. V. Lintsova ◽  
L. V. Popova

Studies of experimental adhesion modifiers based on a mixture of fatty acids from the production of light vegetable oils. The properties of rubber compounds and their vulcanizates obtained using experimental adhesion promoters KK with cobalt content from 7.5 to 16.5% are investigated. The plastic-elastic and vulcanization properties of the properties of breaker rubber compounds based on polyisoprene, the physical and mechanical properties of breaker rubbers and the bond strength in the “rubber-brass-plated steel cord system” were studied. When testing belt rubbers containing experienced adhesion promoters or an imported analog of Manobond 680C, the following features were revealed. The plasticity of the prototypes was in the range of 0.2-0.4. This indicates satisfactory processing properties. The Mooney viscosity of the prototypes was lower than that of the production sample. The use of experienced adhesion promoters instead of the analogue (Manobond 680C) increases the resistance to scorching. On the basis of the analysis of elastic-strength properties, it was found that in terms of the conditional tensile strength, the prototypes were inferior to the serial ones. However, rubbers containing the KK-12, KK-13.5, KK-15 promoters met the control standards. The tensile elongation at break of the experimental rubbers is higher than that of the serial sample. This may indicate the formation of a more uniform cure network in the presence of the test products. When testing rubber-metal-hard composites, it was noted that, under normal conditions, the experienced adhesion promoters have advantages over Manobond 680C. However, at elevated temperatures, under conditions of salt and steam-air aging, they are slightly inferior to Manobond 680C. It has been established that the experimental adhesion promoters provide the required set of technical properties of belt rubbers with a CO2 + content of 12–16.5% wt. Thus, it is possible to recommend the adhesion promoters KK 12, KK-13.5, KK 15 for practical use in the composition of belt rubber compounds. This will allow replacing a foreign-made product and reducing the cost of production.


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