EVALUATION OF INNER SHEAR RESISTANCE OF LAYERS FROM MINERAL GRANULAR MATERIALS

The methodologies used to assess the inner shear resistance of granular layers from minerals measured in the laboratory with and without geosynthetic reinforcing layers are described in this paper. For the measurements, a multi-level shear box is applied without considering vertical loads on the top layer. In the literature and engineering practice, an accepted calculation method for determining inner shear resistance exists. It is the shear force with linear shearing speed, primarily after a peak force value. This can be accounted for in the present case by calculating the average force value for the 40-80 mm shear range using previous scientific and research achievements. The article details each possible additional method and compares it different methods. Three granular materials, as well as six planar geosynthetics, were studied. For this purpose, the results of 216 measurements were considered and processed using 61 different shear function-qualification parameters. The calculations were performed using a simplified function fitting test and a selection process to maximize the allowable relative standard deviations. All three types of materials and four classification parameters were chosen as references for comparability. As a result, only one alternative parameter can be used to determine the reinforcing-weakening values with a maximum deviation of 5% while not producing insufficient results in the placement (ranking) of the individual granular material and geosynthetic pairings. This parameter is the area under the function (integral) calculated on the measurement graph of the 40-80 mm shear range, in kN×mm unit; it gives correct values only if the reference granular material is the considered railway ballast, the shearing plane is the geosynthetic's plane (i.e., the so-called "0‑plane"), and the reference qualification parameter is the original recommended parameter. The best relative standard deviation values were 20% and 30%

Sustainable Freight Transport

This Special Issue of Sustainability reports on recent research aiming to make the freight transport sector more sustainable. The sector faces significant challenges in different domains of sustainability, including the reduction of greenhouse gas emissions and the management of health and safety impacts. In particular, the intention to decarbonise the sector’s activities has led to a strong increase in research efforts—this is also the main focus of the Special Issue. Sustainable freight transport operations represent a significant challenge with multiple technical, operational, and political aspects. The design, testing, and implementation of interventions require multi-disciplinary, multi-country research. Promising interventions are not limited to introducing new transport technologies, but also include changes in framework conditions for transport, in terms of production and logistics processes. Due to the uncertainty of impacts, the number of stakeholders, and the difficulty of optimizing across actors, understanding the impacts of these measures is not a trivial problem. Therefore, research is not only needed on the design and evaluation of individual interventions, but also on the approach of their joint deployment through a concerted public/private programme. This Special Issue addresses both dimensions, in two distinct groups of papers—the programming of interventions and the individual sustainability measures themselves

Efficient practices in railway ballast maintenance and quality assessment using GPR

The need for effective and efficient railway maintenance is always more demanded all over the world as the main consequence of aging and degradation of infrastructures. Primarily, the filling of air voids within a railway ballast track-bed by fine-grained materials, coming up from the subballast layers by vibrations and capillarity effects, can heavily affect both the bearing and the draining capacity of the infrastructure with major impacts on safety. This occurrence is typically referred to as “fouling”. When ballast is fouled, especially by clay, its internal friction angle is undermined, with serious lowering of the strength properties and increase of deformation rates of the whole rail track-bed. Thereby, a detailed and up-to-date knowledge of the quality of the railway substructure is mandatory for scheduling proper maintenance, with the final goal of optimizing the productivity while keeping the safety at the highest standard. This paper aims at reviewing a set of maintenance methodologies, spanning from the traditional and most employed ones, up to the most innovative approaches available in the market, with a special focus on the Ground Penetrating Radar (GPR) non-destructive testing (NDT) technique. The breakthrough brought by the application of new processing approaches is also analyzed and a methodological framework is given on some of the most recent and effective maintenance practices

A STUDY ON INTERMODAL FREIGHT TRANSPORT MODELS IN VIETNAM

Freight transportation is a potential component of the logistics system, which absorbs between one - third and two - thirds of the total logistics costs. In the transport field, transportation companies try to search the best operating ways or alternatives which could help them compete with others, so there are competitions among different transport modes (road, rail, air, and water modes). Instead of finding the better alternative for such competition, this paper has considered to build the freight transport networks based on the coordination among modes, which makes the transport systems operate more effectively. This concept is called intermodal freight transport or intermodalism model. Depending on different conditions, the best suitable intermodalism models will be proposed. Author will study, construct, analyze, evaluate, and apply the intermodal freight transport models that suit for the special conditions in Vietnam. Besides, constructing the optimum transportation networks, which are used for collecting or distributing freight to/from depot centers from/to customer zones, is a challenge of logicians. In this paper, author will present one of the general ways to do it. Transportation model is built, in which objective and constraint functions are formulated. An experience method to solve this problem is proposed, where it follows three phases. The first one is that a possible set of tours is generated. An optimum alternative, then, is determined in phase 2 by using optimization program, Lingo software. Finally, suitable fleets are assigned to response it. To illustrate the method, an example transportation problem is presented.화물운송은 물류시스템에서 총 물류비용의 1/3 에서 2/3 을 줄일 수 있는 중요한 요소이다. 운송회사들은 최선의 경로나 다른 경쟁력 있는 운송수단(도로, 철도, 항공 및 선박)을 통해 비용을 줄일 수 있는 대안을 찾기 위해 노력한다. 본 논문에서는 운송 시스템을 더 효과적으로 만들기 위해 운송수단 사이의 관계를 기반으로 한 화물운송 네트워크를 구성하고자 한다. 여러 상황을 고려한 최선의 복합운송 모델을 제시할 것이다. 베트남 상황에 알맞은 복합운송모델을 구성, 분석, 평가할 것이다. 화물을 유통 거점으로부터 소비자에게 또는 소비자로부터 유통거점으로 모집 또는 분배를 위한 최적의 운송 네트워크를 구성한다. 운송모델의 구성에는 객관적이고 제약적인 기능이 나타난다. 이러한 문제를 해결하기 위한 method 는 다음 3 가지를 따른다. 첫째, 가능한 모든 루트를 나열한다. 둘째로 최적의 대안은 최적화 프로그램인 'Lingo software'를 이용하여 결정한다. 마지막으로 알맞은 루트는 응답을 통해 선정한다. 수송수단의 문제점을 보여줌으로서 method 를 설명하고자 한다.Chapter 1: Introduction = 1 1.1 Introduction = 1 1.2 Objectives = 2 1.3 Scale and scope = 2 1.4 Structure of thesis = 3 Chapter 2: Literature Review = 4 2.1 Transportation options = 4 2.2 Intermodalism = 4 2.2.1 Definitions of intermodalism = 4 2.2.2 Characteristics of intermodalism = 6 2.2.3 Factors impact on transport mode selection = 6 2.3 Spread of intermodalism = 7 2.3.1 Europe = 8 2.3.2 North America = 8 2.3.3 Canada = 8 2.3.4 The Baltic States = 8 2.3.5 Asia = 8 2.3.6 Australia = 8 2.4 Methods to select the best combination of transportation modes = 9 2.4.1 Usage of the Shortest Path Problem = 9 2.4.2 Usage of AHP for model ranking = 10 Chapter 3: A brief introduction about Vietnam = 16 3.1 Geography = 16 3.2 Economy = 16 3.3 Transportation infrastructure and superstructure = 18 3.3.1 Roads = 18 3.3.2 Rail = 19 3.3.3 Waterways = 19 3.3.4 Airways = 20 3.4 Freight transportation = 20 3.4.1 Freight transport volume vs. freight traffic volume = 20 3.4.2 Domestics freight transport costs = 22 Chapter 4: Methodology = 24 4.1 Description of methodology = 24 4.2 An analysis of intermodal applicability in Vietnam = 25 4.3 Model selection and evaluation methodology = 26 4.3.1 Selection factors = 26 4.3.2 Market segmentation = 27 4.3.3 Evaluation method = 29 Chapter 5: Model Proposition, Selection, and Evaluation = 31 5.1 Model proposition = 31 5.1.1 Road-Rail-Road transport system = 31 5.1.2 Road-Coast-Road transport system = 33 5.1.3 Road-Air-Road transport system = 34 5.1.4 Inland waterway-Coast-Inland waterway transport system = 35 5.2 Evaluating intermodal freight transport network design = 36 5.2.1 North-Middle market segment = 37 5.2.2 Middle-South market segment = 39 5.2.3 North-South market segment = 41 5.3 Model ranking based on AHP method = 43 5.3.1 AHP model construction = 44 5.3.2 Results = 47 5.4 Chapter discussions and conclusions = 47 Chapter 6: Transportation Network Problems: An experience way to construct and solve = 49 6.1 Transportation problem description = 49 6.2 An experience-solving method = 50 6.3 A numerical example = 54 6.4 Chapter conclusions = 56 Chapter 7: Conclusions and recommendations = 57 7.1 Conclusions = 57 7.2 Recommendations = 57 7.2.1 Factors that make intermodalism successful in Vietnam = 57 7.2.2 Recommendations for further studies = 59 References = 60 Appendix = 6

Toward a Sustainable Transport Development in Asia and the Pacific

Despite remarkable growth during the last decade, Asia and the Pacific still faces extensive basic infrastructure needs. Furthermore, to cope up with the reduced export demand from advanced economies arising out of the ongoing financial crisis, the region needs to enhance its connectivity through developing transport infrastructure at the national and regional level to rebalance its growth towards regional demand through enhancing intraregional trade. However, building massive transport infrastructure will have profound implications on environment and climate change at the national, regional and global levels as well as on scarce energy resources. This paper presents the needs and benefits of transport connectivity and financing requirement of Asian economies during 2010-2020; and analyzes the major challenges and prospects in developing sustainable transport connectivity. Finally, the paper provides policy recommendations on what the region can do to meet these challenges.sustainable transport, infrastructure, connectivity, financing infrastructure, environment and climate change, Asia and the Pacific

ENVIRONMENTAL IMPACT ASSESSMENT BASED GEOGRAPHICAL INFORMATION SYSTEM FOR LAND SUITABILITY OF PETROL FILLING STATIONS

A sustainable approach for protection of the natural environment remains the topic of interest for the developers in the developing countries. There has been a growing concern that development activities have the potential to cause severe damage to the environment. The rapid growth in urbanization offered an ample demand of vehicles, resulting more fuel consumptio

Risk analysis of LPG tanks at the wildland-urban interface

In areas of wildland-urban interface (WUI), especially residential developments, it is very common to see liquefied petroleum gas (LPG) tanks, particularly with a higher ratio of propane, in surface installations serving homes. The most common tanks are between 1 and 5 m3 of capacity, but smaller ones of less than 1 m3 are more frequent. In case of accident, installations may be subject to fires and explosions, especially in those circumstances where legal and normative requirements allow very close exposure to flames from vegetable fuel near LPG tanks. In this project, it is intended to do a comprehensive diagnosis of the problem, addressing the compilation of information on real risk scenarios in historical fires. First, a preliminary presentation of the properties and characteristics of liquefied petroleum gas will be exposed. Its physical and chemical properties, production methodology, pressure and temperature diagrams and important considerations will be defined when using this type of substances in a storage tank of a certain volume. Next, a review of the situation of the existence of LPG tanks in the urban forest interfaces will be exposed. In this case, the main accidents caused by problems with the storage of LPG will be analyzed taking into account the relevance of BLEVE events in this type of incidents. To do this, the main scenarios that could take place in the event of a fire will be presented. Next, the existing legislation on the storage of LPG in these environments in some Mediterranean countries will be studied. In order to develop a comprehensive analysis, the main safety measures and distances will be considered, as well as the awareness of the possibility of vegetation material in the vicinity of LPG storage tanks, which is the main problem that will arise in a possible BLEVE scenario in case of fire. To finalize and facilitate understanding, a comparative table will be included with the aim of visualizing the main advantages and legislative deficiencies between the different countries. Following, the state of the art in terms of modelling LPG accidents at the WUI will be reviewed. Trying to simulate and predict this type of scenarios, it will see the models normally chosen to obtain the tolerable values selected and the answers obtained in each case. Finally, several fire scenarios will be simulated by means of a CFD tool (FDS, Fire Dynamics Simulator). In these simulations, the wind velocity and the distance of the combustible vegetal mass to the tank will be controlled in a WUI fire in which there is a tank of fixed dimensions. The temperature and the heat flow in each of the scenarios will be obtained, and the differences among the location of the sensors and the characteristics of the scenario will be analyzed. As a conclusion, it has been observed that there is a great amount of variables that are not contemplated by the regulatory organisms and that the existing legislation does not guarantee the safety of the population in this type of environment. From the simulations results, variables as temperature should be studied for further characterizations

Optimal Control of Hybrid Systems and Renewable Energies

This book is a collection of papers covering various aspects of the optimal control of power and energy production from renewable resources (wind, PV, biomass, hydrogen, etc.). In particular, attention is focused both on the optimal control of new technologies and on their integration in buildings, microgrids, and energy markets. The examples presented in this book are among the most promising technologies for satisfying an increasing share of thermal and electrical demands with renewable sources: from solar cooling plants to offshore wind generation; hybrid plants, combining traditional and renewable sources, are also considered, as well as traditional and innovative storage systems. Innovative solutions for transportation systems are also explored for both railway infrastructures and advanced light rail vehicles. The optimization and control of new solutions for the power network are addressed in detail: specifically, special attention is paid to microgrids as new paradigms for distribution networks, but also in other applications (e.g., shipboards). Finally, optimization and simulation models within SCADA and energy management systems are considered. This book is intended for engineers, researchers, and practitioners that work in the field of energy, smart grid, renewable resources, and their optimization and control

"Test-site operations for the health monitoring of railway ballast using Ground-Penetrating Radar"

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