The design criteria were introduced in this paper to design a landfill cover barrier layer using the compacted soil-fiber mixture for the future application (i.e. park, residential, etc.). Polypropylene (C₃H₆) fiber was used as an additive material for soil samples. The soil specimens compacted under the conditions of maximum dry density and optimum water content. In this study, the design objective in using the compacted soil-fiber mixture is to determine the range of fiber content (i.e. 0.0% - 1.2%) within which the soil specimens will have adequate compaction characteristics, compressive and tensile strength, minimum amount of cracking, and low hydraulic conductivity. It is found that the fiber content that maximized the maximum dry density was considered insignificant. Fiber content in excess of 0.8% showed significant increase in the unconfined compressive strength. The tensile strength significantly increased for soil specimens exceeding 0.2% of fiber content. An acceptable limiting value of the crack intensity factor to prevent desiccation cracking for soil specimen was found between 0.6 and 0.8% of fiber content. Moreover, the fiber contents up to 1.2% maintained the hydraulic conductivity within acceptable levels. As a result, the optimum fiber content that was necessary to meet the overall acceptable zones based on the parameter design investigated in this study was found and reported in this study.

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Several studies in the literature have investigated the shear behaviour of soil-steel interface. Furthermore, a normalized relative roughness parameter, R_n, has been used successfully to describe the shear behaviour of the sandsteel interface. On the other hand, few studies are available in the literature regarding the interface shear behaviour of fiber reinforced polymer (FRP). The aim of this study is to investigate the shear behaviour of soil-FRP interface and examine the validity of R_n for the FRP case. Experimental program using a modified direct shear test apparatus was conducted for this purpose. The testing materials in this study include two different types of FRP, and five different-size glass beads in terms of the mean particle size, D₅₀. The experimental results show that the interface shear behaviour of FRP is different than steel. The observed difference could be explained in terms of the expected contribution of the interface ploughing resistance in the FRP case compared to the steel where its interface shear behaviour is mainly controlled by the interface sliding resistance.

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In this study, a hydrodynamic and solute transport model was applied to evaluate the effect of dredging on salinity intrusion in the estuary of the Mekong River, southern Vietnam. The model was calibrated and validated with available hydrographic measured data in 2000, 2004 and 2009. The flow and salinity at different positions in the river were dynamically assessed using the hydrodynamic and advection dispersion models. The factors of velocity, flow, water level providing flow boundary parameter for two-dimension model were calculated for both dry and flood season, while salinity was calculated only for the dry season to evaluate the impact of dredging to salinity intrusion process. The results of salinity intrusion simulation for 15 days show that the impact of dredging only occurs in the Quan Chanh Bo channel and does not affect the large river system. The minimum and maximum salinity concentrations along Quan Chanh Bo channel were predicted to be in the range of 2.0-6.0PSU.

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Parks are an important aspect of an ideal city. In the “neighborhood development” concept, the public park is the core of a neighborhood block, which is one of the basic components of the city. Using the neighborhood parks in Kitakyushu, Japan, as a case study, this research proposes an evaluation system for parks in urban area. First, the study uses GIS to identify each neighborhood park and define the neighborhood community. It then classifies neighborhood parks according to the land-use pattern of their communities. Next, the study develops an assessment index and used it for principal component analysis. Finally, based on the results of the analysis, the study comprehensively evaluates the community and park system in Kitakyushu city, Japan. The findings suggest that comparative evaluation between the different parks can help in understanding the characteristics and problems of existing information.

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Based on the land use patterns in the years of 1990, 1995, 2000 and 2005 acquired with the spatial technology of geographic information system (GIS), this study takes Kitakyushu city in Japan as a case to analyze and forecast the dynamic change and transformation of various land use types. Firstly, we use the spatial distribution maps to describe the changes of area and spatial distribution of land use in the past 15 years, and then the dynamic change models are established to evaluate the changes of speed and intensity of land use. The results indicate that each land use type has changed remarkably as the urbanization, and that the land use intensity has been transferring from extensive type to intensive type. Finally, we develop a transfer matrix of Markov to track the mutual transformation processes among the land use types, and to forecast the change tendency of future land use. The forecasting results reveal that the urban land will keep increasing at a decelerated speed, and it will be a long process for land use intensity to reach to the urbanization level.

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The Karst area is typical eco-environmental vulnerable area, where insufficient farmland and serious soil degeneration offer vulnerable ability to endure the natural disasters. Consequently, vulnerable eco-environment can't coordinate with rapid social economic development, which leads to its feeble sustainable developmental ability. The Karst area of Chongqing in China as a study case , this paper sets up 13 influencing factors of eco-environment vulnerability to be assessment indexes, including earth surface of carbonate rock salt, area of mountainous region, area of slopping upland farming, degree of rock desertification (classified by gently, moderately, seriously), forest coverage, loss area of water and soil, soil erosion modulus, slip volume density, cultivation index, farmland area per capita, agriculture population density. Subsequently, the paper uses analytic hierarchy process (AHP) to endow indexes weight, and proposes an assessment model by using fuzzy mathematics method to analyze and assess the eco-environment vulnerability of Karst area. Finally, the assessment results are rankly divided. Results indicate: there are 3 potentially vulnerable counties, 10 gently vulnerable counties, 6 moderately vulnerable counties and 6 seriously vulnerable counties among the 25 Karst counties in Chongqing.

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With the gradual development of the new rural construction, and the continuous improvement of the rural per capita living space, sustainable development of the rural living environment is becoming an increasingly urgent task. This paper selected three different terrain villages in the rural area of Hangzhou as a study object, which located in the Middle and lower reaches of Yangtze River. Firstly, the investigation, collection and analysis on the building status, energy data and residents' subjective feeling of the three villages had been done through basic research and sampling questionnaire. Secondly, it selected two typical housing in each village, separately carried on the measurement of the building physical environment and computer quantitative simulation of the ventilation, lighting, and energy consumption, along with the comprehensive evaluation with the simulation results. Finally, the major existing problems of the living environment in the rural areas have been found, according to which some operable implementation strategy and policy Suggestions have been put forward.

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