scholarly journals Application of ash and slag mixtures in the road construction: current directives and recommendations

2018 ◽  
Vol 2018 (8) ◽  
pp. 25-31
Author(s):  
Patryk Damian Lewandowski ◽  
Michał Pachnicz

Nowadays civil engineering is constantly searching for cheaper substitutes of already known and commonly used building materials. Especially road and railway industries focus on reducing the costs, as large objects like highways and railroads can require high material usage in order to prepare required foundation. Therefore, the use of waste (in particular fly ash and slag mixtures) as a foundation material not only can bring savings but also is environment friendly, as it creates new ways to dispose waste. However, it is problematic to use the mentioned materials due to ambiguities revolving around current recommendations for their application. In the article, a comprehensive review of the fly ash and slag mixtures use in civil engineering is made. Guidelines and requirements for the use of waste material as a road foundation material are discussed. Discrepancies between the recommendations are analyzed and the potential changes are suggested. The article is also the basis for further investigation of fly ash and slag mixtures composition improvements.

2011 ◽  
Vol 99-100 ◽  
pp. 924-927 ◽  
Author(s):  
Dong Xing Wang ◽  
Hong Xing Wang ◽  
Wen Zhao Chen

Solidified dredged materials as environment-friendly materials in construction domain are increasingly popular because of their better mechanical performance and low pollution. Based on the physical characteristic of dredged marine sediments, a series of tests, such as unconfined compressive strength test and tensile strength test, were performed to explore the mechanical properties of cement/lime-fly ash treated sediments for the beneficial use in road construction. Finally, the reinforcement mechanism of solidified sediments was explored by SEM tests from the point of view of the formation of CSH phases and the change in microstructure.


2006 ◽  
Vol 34 ◽  
pp. 81-94
Author(s):  
Megh Raj Dhital

The high-intensity rain of 5-13 July 2004 activated numerous landslides, gullies, and debris flows in the watershed of the Dudh Koshi River in east Nepal. As a result, the Hilepani- Jayaramghat- Diktel Environment-Friendly Road was devastated. Apart from the rainfall, geological, geomorphic, land use, and road construction practices were other important factors leading to the disaster. Most of the damage was concentrated on concave slopes, whereas the ridges and convex slopes were relatively safe. The entire alignment was devoid of any breast or retaining walls necessary to protect the high, steep, and bare soil cut slopes, and it resulted in extensive cut slope failures. Similarly, side and cross drains were almost nonexistent. As a result, severe damage was seen at almost every gully crossing. There were very few gully protection structures (viz. check dams) and, like the retaining walls constructed below the road, they also suffered from poor construction quality and failed due to weak foundation and inadequate keying practices. Some of the most awkward structures were the loops founded on unstable slopes with high (up to 15 m) and robust gabion walls at the bends, and deep box cuts above them. In these circumstances, the concentrated runoff and subsequent debris flow from the box cut devastated the entire hairpin bend.


2021 ◽  
Vol 265 ◽  
pp. 04007
Author(s):  
N. G. Mitrofanov ◽  
A. Yu. Sushilova

The following paper presents some results of long-term research on the urgent problem of recycling waste products and their use in road construction. The studied new materials and technologies are justified by the developments of Tyumen Industrial University. The aim of this work is to prove the technique, checking the ecological safety of the road materials with the use of waste products. Research techniques and test subjects are quantitative chemical analysis and biological testing of road material samples with waste additives obtained during drilling and oil production. Along with the standard procedures for analyzing the contamination and toxicity of water extracts, the authors have proposed and tested the evaluation of repeated and long-term extractions, imitating the possible environmental impact of waste products. The obtained results showed the environmental safety of the road-building materials based on wastes.


2018 ◽  
Vol 45 ◽  
pp. 00081 ◽  
Author(s):  
Izabela Skrzypczak ◽  
Wojciech Radwański ◽  
Tomasz Pytlowany

There are two technologies for road construction, e.g. an asphalt one and a concrete one, that exist in the market of road infrastructure at the moment and they both have their advantages and disadvantages [prof Jan Deja of Krakow Mining Academy, Cathedral of Building Materials Technology].The advantage of concrete pavement consists of the fact that it doesn’t require bigger financial expenditures within 10 – 20 years of exploitation (provided that necessary pavement maintenance treatments are carried out). In the case of asphalt pavement it is necessary to mill the wear off layer of the road already after 6-7 years. It leads to the question: which of these technologies should be chosen, which is better? The work hereby carries on analyses concerning a comparison of the technologies for road constructions; the asphalt one and the concrete one. Based on the analyses carried out with the use of the Hellwig method it was found that the achieved values of synthetic meters for asphalt and concrete pavements are close to each other, which may indicate that both technologies are comparable within the sectors taken for analyses in relation to accepted technological-technical and usability features.


Author(s):  
Daniela Ionescu ◽  
Joe Petrolito

An efficient transportation system requires a good network of roads provided with pavements that can withstand both the heavy and frequent traffic demands and environment variations while requiring minimal maintenance. However, roads are sometimes built where the sub-grade soil does not comply with the specifications and needs to be replaced with an acceptable soil that satisfies these requirements. To minimize the construction cost and the impact on the environment that the road construction would have, stabilizing agents (lime, cement or fly ash), are commonly used to improve the characteristics of in-situ soils. However, this process adds to the cost of road construction and maintenance. Therefore, alternative, environmental-friendly solutions have been investigated to reduce these costs. In recent years, enzymes have been used successfully to stabilize mostly fine-grained soils. This paper reports on an on-going research program on the use of various stabilizing agents to improve the properties of in-situ sub-grades for rural roads. Two locally-sourced soils were used in this investigation. The effects of cement, cement-fly ash mix and Perma-zyme binders on the properties of the selected soils were investigated. A series of tests was performed to establish the strength, stress-strain and deformation characteristics of the supplied soils. The results were compared to establish if Perma-zyme is suitable as stabilizing agent for the supplied soils.


2010 ◽  
Vol 168-170 ◽  
pp. 2078-2081
Author(s):  
Zhan You Yan ◽  
Yu Shu ◽  
Jian Qing Bu ◽  
Xiang Guo Li

Fly-ash is an industrial waste burning pulverize coal boilers for thermal power plant and large enterprises, the steel slag is too a residue generated waste in steelmaking industrial processes, the average for every ton steel to produce half ton steel slag, steel slag and fly ash discharge amounts is very big, utilization ratio is very low. At present, a large number of steel slag is used of reclamation work, the remaining items is used rarely and large number is left storage. This paper is introduction steel slag and fly ash to do road base-course material, such can make good use of industry residue waste in large amount to reduce exploitation and cut down natural building stones, it is an application for ecological building materials again. Major study the steel slag and fly ash road features, these tests include materials compaction reality among them, mix design, unconfined compressive strength, split tensile strength, resilient modulus and other commonly used performance. Through comparative analysis, this two materials combination has good use of quality, it has greatly better than other materials such as lime-fly-ash stabilize crushed stone and lime-fly-ash soil and other materials. In particular, it has very good performance to reduce road base-course crack, the material has good resistance shrinkage and temperature shrinkage ability. Therefore, the combination of steel slag and fly ash can be done entirely road base-course and extend the road life.


2011 ◽  
pp. 19-33
Author(s):  
A. Oleinik

The article deals with the issues of political and economic power as well as their constellation on the market. The theory of public choice and the theory of public contract are confronted with an approach centered on the power triad. If structured in the power triad, interactions among states representatives, businesses with structural advantages and businesses without structural advantages allow capturing administrative rents. The political power of the ruling elites coexists with economic power of certain members of the business community. The situation in the oil and gas industry, the retail trade and the road construction and operation industry in Russia illustrates key moments in the proposed analysis.


Author(s):  
Л.Н. Крячко

Постановка задачи. Изучение предмета «Иностранный язык» в техническом университете предполагает усвоение обучающимися терминологической лексики в соответствии с выбранной специальностью. Опыт преподавания показывает, что студенты испытывают трудности, связанные с запоминанием терминологических единиц и употреблением их в речи. Использование на занятиях по иностранному языку приема обучения терминологической лексике посредством опоры на внутреннюю форму данных лексических единиц позволяет оптимизировать процесс усвоения обучающимися специальных терминов. Результаты. Проведенное исследование дает основание утверждать, что анализ внутренней формы образованных семантическим способом англоязычных терминов специальности «Автомобильные дороги» позволяет выявить деривационно-ассоциативную связь терминологических единиц с лексикой общенационального языка, послужившей основой для вторичной номинации. Данные лексические единицы в большинстве случаев представляют собой хорошо знакомые студентам слова, обозначающие части тела человека и объекты, находящиеся в его близком окружении : одежду, посуду, инструменты, явления природы, представителей животного мира и т.д. Выводы. Ознакомление студентов дорожно-строительной специальности с внутренней формой изучаемых англоязычных терминов, выявление ассоциативных связей терминологических единиц со знакомыми студентам и широкоупотребительными словами общенационального языка, а также выполнение в аудитории специально разработанных тренировочных упражнений помогают снять трудности усвоения обучающимися терминологической лексики и облегчают ее запоминание. Statement of the problem. The study of the “Foreign Language” subject at a technical university involves students’ learning the terminology in accordance with the chosen specialty. The teaching practice shows that students experience the difficulties associated with memorising terminological units and using them in the speech. Applying the method of teaching the terminology based on the internal form of these lexical units at foreign language classes makes it possible to optimise the process of learning special terms by students. Results. The research that has been carried out gives reason to argue that the analysis of the internal form of the English “Automobile roads” specialty terms created in the semantic way makes it possible to reveal the derivational and associative relations of the terminological units with the national language words which served as the basis for the secondary nomination. In most cases, these lexical units are the words that are well known by the students and indicate the parts of man’s body and the objects that are present in man’s immediate environment: clothing, dishes, tools, phenomena of the nature, representatives of the animal world, etc. Conclusion. Introducing the internal form of the studied English terms to the road construction specialty students, identifying the associative relations of the terminological units with the well known to the students and widely used words of the national language, fulfilling the specially developed training exercises in the classroom help the students to overcome the difficulties of learning the terminology and to facilitate its memorization.


Author(s):  
M.A. Piskunov ◽  

Russian forest sector forms an attractive market for harvesting and logging equipment, however the position of Russian manufacturers is extremely weak. A brief overview of the current state of the market is presented with reference to the open sources. Its features are mentioned as compared to the road construction and agricultural machinery sectors. Three transnational companies dominate the Russian market of harvesting and logging equipment: John Deere, Ponsse and Komatsu. Most of the purchased equipment falls on machines for cut-tolength technology, such as harvester and forwarder. The market volume of new machines is estimated at 330–420 forwarders, 165–300 harvesters, about 30–40 feller bunchers and the same number of skidders. There were two waves in the consolidation of the position of foreign companies in Russia. The first was connected with the delivery of equipment and the development of foreign brands in Russia against the background of still high-profile positions of Russian manufacturers in the market. The second is the takeover of enterprises having a service network and reputation by diversified transnational corporations. The main strategies of the leading companies in the current situation are the export of equipment to Russia and the development of a service network. Companies do not turn to another level associated with the opening of production sites or joint ventures for the production of harvesting and logging machines. The Russian market is characterized by the absence of a strong Russian manufacturer of harvesting and logging machines, which is ready to significantly influence or actively participate in the processes of import substitution. The position of such a manufacturer is gradually occupied by the Belarusian Amkodor Holding. The purchase of new harvesting and logging machines can afford major timber companies. The main production sites of harvesting and logging machines are located in Finland, Sweden, USA, and Canada. In order to support forestry machine engineering, in addition to economic measures of stimulation approved in other sectors, it is proposed: to organize the work of scientific forest engineering centers on the base of public-private partnership with the financial support from the major vertically-integrated timber corporate groups; to stimulate the development of Russian sector-specific information technologies for harvesting and logging; to initiate the partnership with companies from the People’s Republic of China to launch the design and production of new-generation harvesting and logging machines.


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