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Numerical implementation of an anisotropic constitutive model for clays (SANICLAY) is presented. Moreover, a case study in which a soil embankment is placed on a K₀-consolidated over-consolidated clay is analyzed by conducting an elastoplastic fully-coupled finite element analysis. It is shown that anisotropy has significant impact on the ground settlement caused by the placement of soil embankment and on the pore pressure generation and dissipation within the foundation soil. The simulations using SANICLAY favorably compare with the field measurements of ground settlement and pore pressure. The drawbacks of the use of an isotropic elastoplastic model (Cam Clay) are also demonstrated.

Computational simulations are presented for a unique series of centrifuge tests conducted to assess the performance of liquefaction countermeasure techniques. In these centrifuge tests, the dynamic response of an embankment supported on a liquefiable foundation (medium sand) is investigated. The experimental series included: (i) a benchmark test without a liquefaction countermeasure, (ii) foundation densification below the embankment toe, and (iii) use of a sheet-pile containment enclosure below the embankment. This series of experiments documents a wide range of practical liquefaction response mechanisms (including countermeasure implementation). In order to numerically simulate the above centrifuge tests, a new calibrated soil stress-strain constitutive model is incorporated into a two-phase (solid-fluid) fully coupled Finite Element formulation. Comparison of the computational and experimental results demonstrates: (i) importance of post-liquefaction dilative soil behavior in dictating the dynamic response and deformation characteristics of the embankment-foundation system, and (ii) capabilities and limitations of the numerical modeling procedure.

The rigid pavements and rigid base supporting rails can be considered as a strip footing resting over an embankment. In addition, there can also be single or double-strip footings resting over an embankment. These strip footings are influenced by the properties of the soil, slope angle of an embankment, setback distance, and spacing between the footings and the height of embankment. In this study, the bearing capacity factors for the single- and double-strip footings resting over an embankment are evaluated using the finite element method (FEM). The bearing capacity factors $N_c^{\prime }$ and $N_{\gamma }^{\prime }$ are evaluated for different soil friction angles $(\varphi )$, slope angles of embankment $(\beta )$, setback distances $(S)$, embankment heights $(D)$ and spacing between the footings $(t)$. Considering the practical aspect, i.e., the surcharge is not present for footing on an embankment, the $N_q^{\prime }$ is not evaluated in the study. Based on the analysis, it is observed that the bearing capacity factors $N_c^{\prime }$ and $N_{\gamma }^{\prime }$ increase with increase in friction angle of the soil and setback distance and reduce with increase in the slope angle of the embankment. The effect of depth of embankment on the $N_c^{\prime }$ and $N_{\gamma }^{\prime }$ is negligible for smaller friction angles $(\varphi \le 20^{\circ })$, whereas it increases marginally for higher friction angles $(\varphi >20^{\circ })$. Furthermore, the $N_c^{\prime }$ and $N_{\gamma }^{\prime }$ are influenced by the spacing between the footings. This study’s results are compared with the results available in the literature. This study’s results are presented as design charts, and these could be adopted in the practice in routine designs of shallow foundations.

Pond ash is a suitable embankment material for the construction of road. However, this material is not in practice for the construction of railway embankment in India. Very limited basic study is available in the literature. Due to this, study the behavior of pond ash railway embankment under dynamic condition, a pilot project on 'Design of pond ash railway embankment' is carried out by Central Road Research Institute, New Delhi, India. Pond ash was collected from National Thermal Power, Kahalgaon, Bihar, India. In this paper, geotechnical properties of pond ash and local soil are presented. Design and stability analysis of embankment with different height (with or without berm) is carried out considering the uniformly distributed load due to train loading under the water logged and sudden drawdown conditions with earthquake factor. It was observed that critical factor of safety was found for lower height of embankment in comparison to the higher embankment.

Seismic design method of earth structure concerns only the safety factor, the subsidence and the sliding displacement; however, the estimation of the size of slope failures is necessary to judge the remaining function of an embankment. Based on slope stability analysis for a case history in 2009 Suruga Bay Earthquake (Mj6.5), the size of slope failure due to the earthquake was investigated in consideration of the heterogeneity of the ground strength. As a result, we proposed a method for the slope failure size estimation based on the maximum slip surface. The proposed method enables a rational assessment of the functional loss of an embankment in terms of the slope failure size.

The ultimate solution to the high volume of excess foundry sands generated in metal casting facilities is to beneficially reuse them. A variety of possible reuse programs suit the utilization of foundry sands. These programs mainly relate to civil and agricultural applications, e.g., highway embankment, concrete, backfills, topsoil, and growing amendments. Foundry sand exhibits qualified physical, mechanical, or chemical properties for these end-use products and is acknowledged as a marketable resource. Most often, foundry sand is characterized to match a target material, which has been adopted as a standardized component in an end-use product, e.g. fine aggregate in concrete. If the match gives favorable outcomes, the foundary sand is introduced fully or partially replacing the target material to form a technically competitive end-use product, e.g. foundry sand used in concrete. In addition to its engineering qualifications, foundry sand's environmental safety is also ensured to comply with regulations. The chemical characterization of foundry sand needs to be accomplished to demonstrate that it will not pose a thread to environments and human health during reuse programs. This chapter is organized to present the system (foundry) sand operation, foundry sand generation and management, chemical characterization of foundry sand, reuse applications of foundry sand.