Dhaka city has experienced a rapid growth of urban population for the last 40 years. This high population increase demands rapid expansion of the city. Unfortunately, most parts of the Dhaka city having competent subsoil for building construction are already exhausted. As such new areas are being reclaimed by both government and private agencies using dredge fill from nearby river sources. Sub-soil investigations have been carried out in different reclaimed areas within the city. It is found that top filling layer is non-plastic fine sand. Mean grain size of which varies from 0.15 to 0.20 mm. A very soft organic layer exists below the filling layer which is highly plastic and highly compressible. Field SPT N-value of filling layer and organic layer vary from 2 to 11 and 1 to 2, respectively. Attempts have been made to correlate unconfined compressive strength with SPT N-value, plasticity index, and organic content. Attempts have also been made to correlate compression index with organic content and initial void ratio of the soft organic clay. The correlations of the soil properties with organic content are variable and in most of the cases no definite correlations could be established. It has been observed that filling sand overlaying organic layer will badly affects the foundation on or having in it. Foundation alternatives have been suggested for the reclaimed areas in Dhaka city.

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Numerical studies were conducted to improve the understanding of the behavior of column-supported embankments in highway widening project. Due to the complexity of the problem, so far, consolidation process and three-dimensional patterns of columns have not been well simulated in most published numerical studies. As a result, the time-dependant behavior and the serviceability of this system have not been well evaluated. In this study, a three dimensional coupled mechanical and hydraulic modeling was conducted using ABAQUS to consider consolidation and three-dimensional arrangement of columns. The numerical predictions are analyzed in terms of settlements and increments in vertical effective stresses. Firstly, the effectiveness of the use of columns and caps is studied. Afterwards, a parametric analysis is performed to study the influence on the soil-columns and caps system of the deformability and the effective friction angle of the embankment. At last some conclusions are obtained from the result of the numerical calculation.

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A vacuum consolidation test was successfully carried out in a (more than 25 m) thick soft clayey deposit in Shanghai. At the site, there is a clayey silt layer located about 5.3 to 6.8 m depth with a relative higher hydraulic conductivity, and a cement deep mixing formed cut-off wall was able to prevent the vacuum leakage through this layer. Prefabricated vertical drains (PVDs) were installed with a spacing of 1.4 m and triangular pattern to a depth of 14 m. The measured results indicate that the degree of vacuum consolidation reached more than 90% in PVD improved zone for a period of about 38 days. Analysis results indicate that the vacuum pressure induced ground deformations can be calculated reasonably well by a previously proposed method. Further field monitoring results show that one month after stopping the vacuum loading, 10 to 65% of the vacuum pressure induced lateral displacement was rebounded, and the percentage rebounding increased with the depth.

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PCE and TCE saturation distributions are generated with stochastic models to incorporate spatially varying aquifer properties. The influence of aquifer property correlation on fluid migration and entrapment is explored in cross-sectional 2D numerical two-phase saturated flow models extracted from 3D geostatistical realizations generated from well-published aquifer data in a nonuniform sandy aquifer. An effort to model a mixture of DNAPL is exercised by employing five compounds DNAPL; a 6:1:1:1:1 by volume ratio of PCE, toluene, 2-chlorotoluene, 1-bromohexane, and 1-bromoheptane. Comparisons of PCE, TCE, and DNAPL mixture suggest that the choices involving chemical waste compositions greatly influenced the saturation and distribution of DNAPL (i.e., pathways and organic spreading). The organic wastes released into the system can escape to the other 2D cross sections as the waste mixtures are more mobile compared to pure phase. Coupled application of stochastic model of aquifer spatial variability as well as chemical waste compositions can significantly influence predicted DNAPL infiltration depth, entrapment, and recovery. The resultant distribution profiles of DNAPL mass within the source zone also have implications for DNAPL recovery and subsequent downstream mass fluxes in remediation operations.

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In 2011, an oil spill occurred off Lach Huyen port in the Northeast of Vietnam, due to vessels collision. The results of collision caused pollution on wide area and surrounding areas. This paper was used MIKE 21 SA model to simulate oil spill transport with five scenarios. The results of simulation showed that spill trajectory and slick area depend on analysis hydraulic regime, wind direction and wave in the study area. This paper presents the model application for simulation spill scenarios. It helps in selecting eco-sensitive regions for preparedness and planning suitable response strategies whenever spill incident occurred.

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China is facing an increasing urbanization in the edge area surrounding main metropolises. This paper targets at analyzing the construction mechanism of land use planning near suburban college towns. Theories and methods such as typical case analysis, mathematical model, and space capacity analysis were used to quantify the mechanism. A typical suburban block, Zijingang Campus Town of Zhejiang University was taken as the case. Since the key index (floor area ratio) indicates the construction intension of a patch of land, it is necessary to examine its appropriate range. The analysis result shows that there are differences in architectural prosperity and urban function by means of several designs. According to the guidelines of urban master planning and urban detailed plan, the Appropriate Floor Area Ratio (AFAR) calculated and deduced based on Economic Floor Area Ratio (EFAR) and Max/Min Floor Area Ratio (MFAR) can be useful in ratifying land development intensity, predicting future tend and evaluating city planning projects.

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This paper has presented a design method of local inhabitant-oriented layout of slab house cluster including two main tasks: 1) analyzing inhabitants' preferences on environmental conditions in “Yangtze River Delta” Area in China through a household investigation; 2) simulating layout evaluated by the inhabitants' preferences. The investigation results showed: the local inhabitants have their own characteristics on environmental conditions, such as general preferences on layouts with dwelling units, roads, green land and individual preferences related with age, sex, occupation etc. The simulation results showed the local design criterions, such as the most suitable height of house, the green land size and the conjunction way between dwelling units and their relations with the types of houses.

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