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A large, uneven settlement that is unfavourable to dam safety can occur between a concrete cut-off wall and the high-plasticity clay of earth core dam built on alluviums. This issue has been often studied using the small-strain finite element (FE) method in previous research. This paper aims to research the interaction behaviour between a concrete cut-off wall and high-plasticity clay using large-deformation FE analyses.

The re-meshing and interpolation technique with a small-strain (RITSS) method was performed using an independently developed program and adopted for large-deformation FE analyses, and a suitable element size for the high-plasticity clay region was suggested. The layered construction process of an earth core dam built on thick alluviums was simulated using the RITSS method incorporating a hyperbolic model for soil.

The RITSS method is an effective technique for simulating the soil–structure interaction during dam construction. The RITSS analysis predicted a higher maximum principle stress of the concrete cut-off wall and higher stress levels in the high-plasticity clay region than small-strain FE analysis.

A practical method for large-deformation FE analysis was advised and was used for the first time to study the interaction between a concrete cut-off wall and high-plasticity clay in dam engineering. Large deformation in the high-plasticity clay was handled using the RITSS method. Moreover, the penetration process of the concrete cut-off wall into the high-plasticity clay was captured using a favourable element shape and mesh density.

In order to study the laws of surface subsidence due to mining coal under thick alluvium of Quandian mine, two survey lines were designed on the surface above the first face. By analyzing the position of the maximum subsidence point of the tendency survey line, the zenith angle was obtained, and the correctness of taking bedrock thickness instead of average mining depth to design the position of the trend survey line in the mining area was confirmed; and based on the analyses of the measured data, the critical size of the gob full opening in the geological and mining conditions didn't follow the general law that the gob would reach the critical size when the panel has moved for a distance of 1.2H₀ - 1.4H₀. These results showed that the bedrock played a major role in the spread of whole overburden subsidence in the geological and mining conditions, while the loose layer had less affection. In addition, based on the analyses of the measured data, some rock movement parameters and probability integral prediction parameters of the surface subsidence of Quandian mine in the geological and mining conditions have been obtained. The study would have some important theoretical significance and practical guidance for implementing mining beneath buildings, water bodies and railways and prevent of this coal field as well as surface structure damage control.

Currently, the existing similar simulation is still limited in the following aspects: un-rotatable laboratory devices, the difficulty in the pavement on steep seams and great error of the experimental data.

To address above-mentioned problems, this study combined theoretical analysis and numerical simulation and developed a rotatable experimental system for similar simulation on steep coal seam mining on the premise of ensuring experimental safety.

The present experimental system mainly consists of the model support, the rotation system and the bearing system. By taking into account the experimental requirements and actual laboratory space, the sizes of the model support and the bearing system were determined. Considering the requirements in space limit and rotation stability, the rotation mode of vertical sliding on the left side and the horizontal sliding on the lower side was designed.

Using programmable logic controller automatic angle control technology, the rotation angle, velocity and displacement of the model can be automatically adjusted and controlled so as to achieve safe rotation and precise control. Finally, the calculation method of the mass of the required similar materials for paving the coal strata at different inclination angles and in different horizons was analyzed, and the related mass proportion calculation software was developed.

The purpose of this paper is to evaluate the potential impact of human-induced intervention on hydrological regimes of Gomti river, one of the important tributaries of the Ganga Alluvial Plain in India aiming at an overall assessment of the status quo.

The research methodology includes following four components: study of basin morphology, sub-surface geology and sediments profile of Gomti river; a comparison of LANDSAT satellite data of 1978 and IRS-1C/LISS-III satellite data of 2008 to study the changes occurring in the built-up area, forest and water bodies of the basin; study of flow patterns in different stretches of river Gomti from 1978 to 2012; and water quality assessment at different sites from origin of the river to its confluence in the Ganges.

The paper shows that over the years, the water source in the tributaries feeding the river Gomti has shrunk, reducing the flow in the river. A steady increase in developed land area due to rapid urban sprawl has occurred in recent decades, due to which forest cover and wetlands are decreasing, the river and floodplains are getting fragmented, the hydromorphology changed considerably and several tributaries are getting dried as a result of indiscriminate exploitation of groundwater. There is no flow in the initial 57 km stretch of the river with wide encroachment in active floodplains. Groundwater over-extraction to meet the demands of increasing population and intensive agriculture has led to reduction in base-flows and in some reaches even negative. Extensive land-use changes in the Gomti river basin (GRB) severely impact the river and floodplain connectivity, the impacts are already evident as several tributaries are getting dried during the non-monsoon months.

The information provided by the paper for GRB is significant for the understanding of the basin and to formulate integrated management and development plan of the basin. Significant changes have taken place in the GRB over the recent past and are still continuing. Because of the chosen river basin and the site-specific research approach, the research results may lack generalization. However, it provides a general framework of analysis which could be applied to other regions.

River channels with their floodplains and adjoining ecosystems have to be addressed as interconnected ecological entity in a holistic way. This requires comprehensive observations of the river systems and catchment characteristics using long-term data. The paper could be used as the starting point in the development of management and development strategies for the basin.

River and its floodplain offer multiple ecosystem services and deserve an integrated approach for their conservation and restoration. Conservation and protection of ecologically intact river-floodplain systems is extremely important and urgently needs integrated planning and management. This paper has adopted a integrated approach to study the integrity of river ecosystems and the potential pressures on them.

Reports on joint efforts by the municipality of Tehran and the scientific body to prepare and implement earthquake reduction policies in the Tehran region, a mega‐city with an approximate population of 10 million people. Focuses specifically on analyzing the seismic vulnerability of the city by considering topography, geology, seismotectonics and seismicity, geotechnical aspects, structural performance, lifelines, emergency services, socio‐economic condition, and search and rescue capabilities. Defines 14 seismic vulnerability indexes for the city and relative vulnerability for 22 further sub‐divisions. Discusses the analyzed data and results. Concludes that a 0.35g scenario could produce a dramatic outcome in Tehran, with extensive damage to buildings and significant numbers of deaths and injuries.

The use of metallic coatings as a protection against corrosion is a subject of considerable antiquity. Cladding and inlaying with gold, silver, and electrum was practised during the Byzantine and early Egyptian civilisations—the tinning of cast iron and copper vessels was known to be established prior to the birth of Christ by the Romans, to whom must also be attributed the lead cladding of ferrous fittings intended for service in marine environments. Metallic coatings can be produced by a wide variety of methods, and on the technique selected depends certain of the factors which control the protective value of the coating, e.g. thickness, uniformity, porosity, adhesion, and purity. Since the type of process used is often restricted by the nature of the article or component to be treated, it is intended to precede a description of the properties of the various metal coatings by a general discussion of the more important methods of coating application.

The primary aim of this research is to investigate the application of open source geographic information system software, geographical resources analysis support system (GRASS) for landslide hazard assessment.

Five parameters affecting landslide occurrence derived from topographical, geological and land use maps of Cameron highland were used for the assessment.

The results showed that about 93 percent of the study area falls under zone II that is of low hazard, with less than 7 percent on zone III with moderate hazard and only less than 1 percent falls under zone IV, which is of high hazard.

The accuracy of the landslide hazard map needs to be assessed by cross‐correlation with landslide occurrence in the field.

The map produced showed the potential application of GRASS as a tool for producing landslide hazard assessment map.

The major outcome of this research is the possible use of open source GIS software in the application of landslide hazard assessment. The capability of GRASS in performing such environmental assessment will certainly attract many researchers and organizations with limited budgets, especially in developing countries such as Malaysia.

The purpose of this paper is to focus on the assessment of water resources in the Seybouse middle sub-basin. Analyses of water and various current uses are used to draw attention to the necessity of implementing water resources integrated management into a plan aiming at a rational exploitation.

Any sustainable management of water resources is closely dependent on the ability to accurately assess the quantity and quality of available water resources that are used as water supply for the population, agricultural production, industrial or energy. The analyzed and processed available data serve as database for integrated water resources management.

Analysis shows that the annual water supply is represented by 71 percent of the surface water resources and 29 percent of groundwater. The total volume of water used in the middle Seybouse basin is estimated at 36.22 hm3/yr. The predicted water needs are estimated to 79.19 hm3/yr in 2030. The groundwater of the Guelma alluvial aquifer exhibits a calcium chloride-facies general trend. The evolution of the chemical elements is related mainly to the geological nature of the reservoir lithologies. The heavy metals do not exhibit clear anomalies, but the surface water of the majority of streams is heavily infected with bacterial germs.

The obtained results show that the Seybouse middle sub-basin needs twice as much water by 2030 for the different uses. This requires a better management of water resources for a sustainable development in this specific region of Eastern Algeria.

This paper is devoted to the management of water resources in a specific region (the middle Seybouse basin) which constitutes an interesting example of considerations to be taken for a sustainable development.

The purpose of this paper is to assess the ground water quality and salinity issues in the fast developing coastal urban lands of two river basins of Thiruvananthapuram district, Kerala, South India.

In order to address the water quality of the basins, field sampling was conducted and the samples were analysed in the laboratory. A comparison with water quality standards was also made and the interpretations of the results were done using GIS and statistical tools.

The values of conductivity, chlorides and salinity show that the coastal areas of Neyyar and Karamana basins are severely affected by salinity intrusion in addition to the pollution problems. More than 90 per cent of the samples are with hardness lower than 100 mg/l. About 70 per cent of the study area is with calcium concentrations lower than 25 mg/l. The content of sulphate and magnesium in Poovar and Poonthura coastal stretches is found to be higher compared to other regions.

Since not much work has been published from the study area on these aspects, the hydrochemical characterization is a very important in deciphering the quality of ground water for its proper management. The water quality evaluation and salinity intrusion studies are very important for the future planning and development of this area.

Nepal is located in mountainous terrain in the Himalayan arc, where landslides are common and are the main cause of natural hazards. On 23 July 2002, daily rainfall of 300mm triggered a landslide of 9,000m³ at head valley of 39^o, which has quaternary unconsolidated gravel rock base coated with thin soil, tree species and shrubs. The landslide changed into debris flow and to flash flood. The average velocity was 30m/sec. and the equivalent friction angle of the materials was 28^o. A total of 16 people lost their lives in Matatirtha village, near to Kathmandu city and millions of properties were damaged. To minimize the disaster, warning system development of standards such as promotion of education level to people and preparation of hazard mapping are suggested.