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Assessing environmental fragility in a mining areafor specific spatial planning purposes

Abstract

Environmental fragility in a mining area is evaluated both in terms of its biophysical (natural) and socio-economic components and their anthropogenic interactions. We identified multiple criteria and indicators for this task, but then reduced these according to responses given by 60 experts in domains related to spatial planning. We used the selected criteria and indicators to develop environment fragility indices for each territorial administrative unit (LAU2) in Gorj County in south-western Romania. The resulting indices reveal quite large spatial variations in fragility and evidence that highly fragile human and physical environments are to some extent intertwined. In this respect, such environmental components as climate, soils, ecosystems, natural hazards and economic issues provide constraints on human activities, whilst humans themselves can, without sufficient care, increase fragility and adversely affect the quality of living environments for present and future generations. We also explore how such estimates of natural and anthropogenic fragility might enable better specific planning for local and regional development that aims to ameliorate both environmental and human adversity in an integrated way.

Open access
Assessment of territorial benefits and efficiency from the construction of motorway and speed train networks: The Czech case

Abstract

The Czech Republic has been developing its motorway network since the 1970s, while efforts to upgrade its railway system from the 1990s have been limited to improvements of existing major lines. Only recently has the government decided to construct new “speed connection” rail lines. This article investigates the possible territorial benefits from the future development of planned motorways and of various speed connection railway options. The modelling is based on Huff’s gravity model that calculates the benefits from improved accessibility, to job and service centres for residents of each municipality. The modelling outcomes are used to compare planned motorway development and rail development options with respect to their efficiency, related to the investment and potential numbers of users.

Open access
The spaces and places of Czech believers

Abstract

Geographical aspects of contemporary Czech religiosity are discussed in this paper. The main objective is to understand and approximate the spaces and places of faith which Czech believers inhabit, construct and reconstruct. An original focus on young believers was broadened to include priests, preachers and older members of several churches in Brno city, and the Přerov and Ústí nad Labem regions. Concepts of space and place, sacred spaces, and the imagery of post-mortem spaces are treated within the context of so-called secularisation and related phenomena. The methodology is based on an inductive qualitative approach using the Grounded Theory of Strauss and Corbin. The data are presented, discussed and ordered following the main themes originating from the research, including: (i) spaces of regular activities (related to the faith); (ii) spaces of dissemination and evangelisation of the faith; (iii) personal places linked with faith; and (iv) an introduction to the imagery of post-mortem spaces. The results document a long-term shift in the attitudes of believers, the change from rather public spaces of community gathering to personal places, influenced by specific secularisation tendencies. Also, the results represent the typical places of faith which are constructed and reconstructed by current Czech believers, and the current imagery of post-mortem spaces.

Open access
Viticultural landscapes: Localised transformations over the past 150 years through an analysis of three case studies in Slovakia

Abstract

The transformation of vineyard landscapes is evaluated in this article by assessing the changes in land cover and landscape diversity in selected study areas in two time periods – from 1867 to 1949, and from then to 2016. The study areas are characterised by a long history of viticulture and with important occurrences of old and new agrarian relief forms. Fine-scale land cover and landscape diversity analysis, as well as the study of historical and strategic documents, enabled an accurate interpretation of the viticultural landscape trajectories and their drivers. Landscape diversity was computed using the Shannon diversity index for each 625 square metre grid unit, and applying other metrics for the entire study area. Our research established that the study areas oscillated during this period between extensification and agricultural intensification, and the general trend confirmed the disappearance of traditional vineyards and a decline in modernised vineyard areas after socialism. Although extensification and intensification are seemingly contradictory processes, it is established that these both increase landscape diversity. In addition, landscape diversity changes in the second period are influenced more by changes in quantitative landscape pattern characteristics via edge density than qualitative patterns, e.g. patch richness, which reflect land use diversity.

Open access
Assessment of Traffic Noise Pollution Due to Urban Residential Road Transport

Abstract

The problem of combating urban noise is closely linked to the rational transformation of the urban environment, which must go through the elimination or reduction of the number of sources of noise, the localization of the noise emission zone, reducing the level of sound sources and protection against noise for the residential areas. Theoretical and experimental studies of acoustic loading on the territory along the highway for the typical section of the urban territory have been conducted. To estimate the complex noise impact from all sources and from individual sources, as well as to predict the total noise exposure for this site, a noise map was constructed using software. As a measure to combat traffic noise in the territory along the highway, the location of the noise protection screen was justified, taking into account the loss of part of the national income as a result of the continuous impact of noise on a person.The results of the research allow to assess the degree of technogenic impact of noise pollution during the operation of the highway, which allows regulating, by administrative and legislative methods, the nature of the impact on natural objects and human health of certain types of activities, as well as reasonably proposing measures that ensure environmental safety when organizing urban streets traffic.

Open access
Bicycle Level of Service Model for the Cycloruta, Bogota, Colombia

Abstract

Segment videos were produced at different peaks to reflect different sampling criteria like land use characteristics, trails, Ciclocarrils and Ciclovia. Each segment was filmed for 20–40 seconds during bicycle rides at a speed of about 5km/h with a camera strapped, at an angle of 45 degrees, on the head. Curb lane variables such as bicycle pathway widths, curb lane motorised volume (veh/h) and vehicle speed (km/h), bicycle volume on segment, and median width were recorded in addition to secondary data. About 1,360 ratings were acquired from study participants and used in the estimation process. Ordered probability models were used to estimate random parameters of cyclists LOS perception to account for unobserved heterogeneity for all respondents. The deviance (1.085) and Pearson Chi-Square (2.309) with 1,635 degree of freedom at 0.05 level of significance shows that our model provides a better fit of the data. The study observed that BLOS was strongly influenced by side path separation, vehicle speed, motorised traffic volume and conflicts with pedestrians. However, many other factors were found to have high probabilities to influence level of service with unit change. They include bicycle lane width, wide outside lane, pavement conditions, trees and benches, daylight, gender and experience of cyclist. The impact of the variety of observed factors affecting bicyclists reveal the nature and character of urban transportation in Bogota which suggests a range of important trade-offs in further planning and management of the Cicloruta bicycle paths.

Open access
Loessoid Soils Improvement – Laboratory Tests and Road Engineering Applications

Abstract

Moisture-sensitive or collapsible soils are materials with high porosity that under the loads transmitted by the superstructure or even under its own weight present additional settlements once the soil is saturated. This category includes loess deposits and other high silt content soils with uneven porosity. A method often used for foundation on these soils is the realization of local loessoid material compacted columns. This paper presents, on one hand, the experimental laboratory programs aiming to achieve some optimal mixtures of local material (loess) and different other materials (sand, bentonite, cement) in order to improve the values of the mechanical parameters of the soil and so, to limit the settlements. On the other hand, it presents a lot of settlement calculations for different case scenarios.

Open access
Reducing the Seismic Vulnerability for RC Buildings by Using Steel Bracing Elements

Abstract

This article aims to highlight, through a comparative study, the efficiency of steel bracing systems used to reduce seismic vulnerabilities in existing buildings with reinforced concrete structures (reinforced concrete frames and reinforced concrete dual structures, general building structures including those used in transport infrastructure). In order to simplify the calculations, the analysis was reduced to the study of the behavior of resistance lines corresponding to four-, nine- and fifteen-level buildings with the same plane distribution. In order to obtain features similar to those of existing building elements, structures were initially loaded with seismic forces corresponding to code P13-63. The next step was to apply to previously dimensioned structures the seismic loads according to P100-3: 2008 in relation to P100-1: 2013, thus obtaining the deficiencies of the existing structures against the requirements of these norms. Correction of these strength and stiffness deficiencies was attempted by introducing X-shaped centric brace systems. The bracing systems used as consolidation methods are of three types: direct bracings stuck in the reinforced concrete frames and bracings of the indirect type, made of internal and external bracing steel frames. Structural calculations were made in the linear elastic field using the ETABS program.

Open access
Study of the Influence of Fibres Type and Dosage on Properties of Concrete for Airport Pavements

Abstract

The paper follows the potential practice of fiber reinforced concrete (FRC) as a solution for airport`s runway pavements, in order to increase the bearing strength, resulting in decreasing the height of the concrete layer that is currently used.

Experimentally, the study focuses on the properties of fiber reinforced Portland cement concrete using 3 different percentages (0.5%, 1% and 1.5% of the concrete volume) and 4 different types of fiber (for 1% percentage – hooked steel fiber 50 mm length, hooked steel fiber 30 mm length, crimped steel fiber 30 mm length and polypropylene fiber 50 mm lenght), using as reference a plain concrete with 5 MPa flexural strength.

More exactly, the study presents the change in compressive and flexural strength, shrinkage, thermal expansion factor, elastic modulus and Poisson`s ratio over fiber type and dosage.

For the highest performance concrete (7 MPa flexural strength), it has been made a study using two methods for rigid airport pavements design (general method and optimized method), and one method for evaluation of bearing strength (ACN – PCN method), which is compared to a plain 5 MPa concrete. Furthermore, the decrease in the slab`s thickness proportionally to the growth of the flexural strength is emphasized by evaluating the slab`s height for a high performance 9 MPa concrete using both design methods.

Open access
The Use of Tuned Mass Dampers for Reducing Structural Vulnerabilities During the Side Movements of Buildings with Reinforced Concrete Frames

Abstract

The present article aims to point out, with the help of a comparative research, the efficiency of tuned mass dampers, modern variants of consolidation ensuring seismic structural safety, used for buildings with a reinforced concrete structure, designed and produced according to the new codes. Case studies were based on structural computations in the linear elastic field using the ETABS program.

Open access