Traditionally, shore protection revetments are designed by limit equilibrium method developed by Pilarczyk (Pilarczyk, et.al, 1998; Breteler, et.al, 1998; Pilarczyk, 2003). The method is also applicable for determining thickness of concrete mattress required to withstand a certain height of waves. However, the method cannot predict deformation of concrete mattress subjected to repetitive wave loads. This paper elaborates the modeling of concrete mattress against the dynamic loading of waves by means of Finite Element Method (Plaxis 2D). It is found that the conventional method is adequate in determining thickness of concrete mattress required against wave height with a factor of safety against lift off in the order of 3.5. The movement of the concrete mattress can be assessed by simulating the wave loads as a concentrated sinusoidal dynamic load at the point of wave impact.

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Desertification is one of the most critical geo-environmental problems. The purpose of this research is to develop the sustainable and high added value anti-desertification method by utilizing medicinal plant licorice (Glycyrrhiza uralensis). It is one of the most valuable medicinal plants which grow naturally in arid region, such as Mongolia and China, but the distribution area is decreasing recently. Therefore, planting licorice in Mongolian arid region by simple and inexpensive method could be “sustainable and high added value greening”, which can satisfy geo-environmental improvement, expansion of distribution area of licorice, and conservation of natural ecological resource at the same time. In order to achieve these purpose, we developed Greening Soil Material (GSM), which is pipe-shaped and has several times higher water and nutrient retention capacity for planting licorice in deteriorated area. In this paper, cultural experiments were conducted in sandy ground simulated arid region and Non-habitat of licorice in Mongolia by using GSM in order to grasp suitable soil water and calcium condition, setting direction and outer layer processing were examined for survival and growth of licorice. It could be revealed that 1) medicinal ingredient in the root tended to become higher by using GSM whose available moisture has 3 to 10 times higher than the Mongolian soils, 2) root length and weight became bigger by using GSM which contains around 18% of CaCO3, 3) survival rate of the conditions setting GSM horizontally was higher than the conditions setting GSM vertically, 4) survival rate of the conditions which GSM contained 10% of compost or potting soil as the dry weight ratio was higher than other conditions, and 5) the more Ca2+ had been kept in the GSM, the higher survival rate was.

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Granulated Blast Furnace Slag (GBFS) is expected to be a useful earthwork material because GBFS increases in shear strength due to its hydration reaction under the natural environment. Authors have already clarified the physical and mechanical properties in the process of hardening by laboratory tests and in-situ case studies. When the earth structures consisted of GBFS which was hardened by a long-term curing are collapsed by external factors such as earthquake, the shear strength is considered to be recovered by its self-restoration due to generation of hydrates at collapsed boundaries. In this study, the self-restoration characteristics induced by the hydration reaction were investigated by observing the hardening process of GBFS which was taken from the in-situ embankment constructed 11 years ago. In addition, a method to estimate the increase of shear strength of GBFS with time was proposed.

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Leachate emanating from solid waste deposited in landfill possess dissolved or an entrained environmentally harmful substances. They consist of soluble organic and inorganic compounds as well as suspended particles. These leachates also have a distinguishing characteristic in that they are highly variable and contain significantly elevated concentrations of undesirable material derived from the waste. Depending on whether leachate flow increases (during rainy season) and decreases (during dry/summer season) can change the composition. The concentration of waste change dramatically changes over the life of the landfill due to chemical degradation and biological decay of organic matter present. Consequently, the physical characteristics also vary considerably depending on the age of the waste. This paper brings out the effect of aging on the leachate characteristics from a municipal solid waste located at the Terra Firma Biotechnologies Ltd situated at Gundlahalli village in Doddaballapur taluk, near Bangalore. For the sake of comparison the leachates from two different parts of the site one from the location where old waste was dumped and another from the location where the waste was dumped relatively recently during the same period. Thus the two leachate samples from the same site representing different stages degradation of waste were collected to represent leachate from old waste and another from relatively fresh waste. The samples were analyzed for various physicochemical parameters to estimate its pollution potential. The results showed that most of the parameters examined in the leachate samples such as colour, conductivity, hardness, BOD, COD, TOC were found higher in the fresh leachate than aged leachate. In addition, low BOD/COD ratio of <0.1 in aged leachate and BOD/COD ratio of 0.33 in fresh leachate are observed. This shows that the major portion is organic matter which is not quickly biodegradable in the leachate from Terra Firma Biotechnology. The compost site is non-engineered solid waste landfill, which has neither bottom liner system nor any leachate collection and treatment system. Hence, leachate may percolate through subsoil causing pollution to ground water and surface water resources. Further the properties of soil below can change due to changing composition of the pore fluid.

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Soil has a great role in construction of any structure. In order to improve the behaviour of the soil, various ground improvement methods are available. Methods like chemical stabilisation, cement stabilisation has been adopted for stabilising cohesionless soils in the construction industry. The inherent drawbacks of these methods are not new to the industry. In the absence of a popular method which can act as an alternative to this, it has been widely used. Soil has microorganisms which are capable of developing strength in the soil, with modification of the existing environment. This is microbial geotechnology. Microbial geotechnology promises to provide a solution for the existing problems along with addressing the environmental issues related to other methods like chemical stabilisation. Work in the aspects of strength improvement has been going on in the world. Unlike conventional methods, the durability of Microbially Induced Calcite Precipitation (MICP) treated soils is of great concern and this paper makes an attempt to study the durability aspects of the MICP treated soils. This paper presents behaviour of MICP soils with respect to strength under different environmental conditions. The strength and durability of poorly graded sand (SP), silty sand (SM) and clayey sand (SC) soils were treated with MICP studied and compared in this paper

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