Effects of various surcharge loading conditions on the stability of soil slopes

The stability of soil slopes is a theme which has great significance within the field of civil engineering, this paper will focus on the analysis of soil slopes under varying surcharge loads. There are two main methods used in the analysis of soil slopes the first is the most commonly used method, the limit equilibrium method (LEM) and the second is a finite element method (FEM) which is becoming more commonly used due to three-dimensional analysis aspect. It is suggested by [1] that the factor of safety is greater for three-dimensional analysis compared to that of two-dimensional analysis. As the accuracy of software packages continues to improve (FEM) will be more commonly used by civil engineers. In this study both analysis methods are used to analyse the effects on various surcharge loading conditions on the stability of soil slopes. By using two different approaches to the analysis of different surcharge conditions, two sets of data are produced both of which can be compared to validate the work. As this topic is widely studied previous papers with a similar research question where used as reference to compare results [2, 3]. The purpose of this study is to highlight the importance of understanding the effects of surcharge loading, it can be seen from previous studies that the focus is generally based on other factors such as the cohesion of the soil, the slope angle, the friction angle and the soil parameters. Whilst they are all individually important, the surcharge loading conditions are often neglected never investing the effects different loads would have on the stability of the soil slope. This shows a gap in the current field of study which this paper will investigate

Numerical investigation into the effect of various surcharge loadings on propped wall excavations and embankments

Several guidance and formulation have been developed in the literature to account for the analysis of external surcharges adjacent to a propped excavation but less attention has been paid to the presence of sloping ground or embankments. However, CIRIA C760 states that the actual ground profile should be modelled and analysed as a series of surcharge loading over the extent of the active side of the wall. In this research, two braced excavation models were analysed of which one was the actual ground profile and the second with a series of surcharge loading representing the embankment adjacent to the excavation. The accuracy, efficiency, and conservation of the proposed approaches were examined on a propped cantilever wall excavation using a finite element geotechnical analysis software PLAXIS 2D. The models were analysed and examined in terms of the bending moment and deflection of the diaphragm wall and the prop load, the model with the actual ground profile was also investigated for any thrust load on the support system should the embankment or sloping ground fail in shear. The results were presented, and comparisons were made. Merits and advantages of the proposed numerical approach were discussed

Narrative Literature Review on Target Cash Conversion Cycle, Speed of Adjustment and Determinants

The purpose of this paper is to review research on target cash conversion cycle, speed of adjustment and determinants of CCC and suggest agenda for future research. Using narrative literature review method, the present study reviews 339 journal articles. Detailed narrative review reveals that target cash conversion cycle, speed of adjustment and determinants of CCC phenomenon are not fully explored and need the attention of researchers

Stability and Asymptotic Behavior of the Causal Operator Dynamical Systems Using Nonlinear Variation of Parameters

The operator T from a domain D into the space of measurable functions is called a nonanticipating operator if the past informations is independent from the future outputs. We will use the solution to the operator di§erential equation y0(t) = A(t)y(t)+f(t; y(t); T(y)(t)) to analyze the solution of this operator di§erential equation which is generated by a perturbation (t) = g(t; yt ; T2(yt)). When this perturbation is from a measurable space then the existence and uniqueness of the solution to the operator di§erential equation will be studied. Finally, we use the nonlinear variation of parameters for nonanticipating operator di§erential equations to study the stability and asymptotic behavior of the equilibrium solution

Modeling and Solution Approaches for Non-traditional Network Flow Problems with Complicating Constraints

In this dissertation, we model three network-based optimization problems. Chapter 2 addresses the question of what the operation plan should be for interdependent infrastructure systems in resource-constrained environments so that they collectively operate at the highest level. We develop a network-based operation model of these systems that accounts for interdependencies among them. To solve this large-scale model, a solution approach is proposed that relatively quickly generates high-quality solutions to the problem. Chapter 3 presents a routing model for a single train within a railyard with the objective of minimizing the total length traveled by train. The difference between this problem and the traditional shortest path is that the route must accommodate the length of the train at any time, subject to yard tracks’ configuration. This problem has application in the railway industry where they need to solve the single-train routing problem repeatedly for simulations of train movements in large complex yards. We develop an optimal polynomial-time algorithm that solves an important special case of the problem. Chapter 4 extends the problem defined in Chapter 3 to a two-train routing problem with the objective of minimizing the overall time possible to schedule the routes in a conflict-free manner. We propose a routing problem that indirectly aims to decrease the overall scheduling time for the two trains. We develop a scheduling model that compares the performance of the solution obtained by the proposed routing model with the solutions obtained by solving the problem as two separate single-train yard routing problems. The comparison indicates a better performance obtained by the proposed routing model for specific problems

Linkage between gold and the stock market in India

India is one of the biggest consumers of gold on the planet. Nufazil Altaf Ahangar shows that gold has been a better safe-haven asset for investors in the country in times of crisis than stocks and shares. He argues, therefore, that policy-makers should take steps to create a more efficient gold market in India

MULTISCALE INVESTIGATION OF DROPWISE CONDENSATION ON A SMOOTH HYDROPHILIC SURFACE

The objective of this work is to identify the fundamental mechanism of dropwise condensation on a smooth solid surface by probing the solid-vapor interface during phase-change to evaluate the existence and structure of the thin film and the initial nucleus that develop during condensation. In this work, an automated Surface Plasmon Resonance imaging (SPRi) instrument with the ability to perform imaging in intensity modulation and angular modulation is developed. The SPRi instrument is used to probe (in three dimensions) the adsorbed film that forms on the substrate during dropwise condensation. SPRi with a lateral resolution of ~ 4-10 μm, thickness resolution of 0.1-1nm, and temporal resolution of 200-10,000 frames per second can measure water films that are monolayer to multilayer in thickness. The governing mechanism of dropwise condensation is investigated in detail for stable dropwise condensation on a smooth hydrophilic substrate. The study shows nucleation is the first step in dropwise condensation and no film greater than a monolayer exists between droplets during stable dropwise condensation. Our result confirms previous experimental works in support of nucleation theory as the mechanism of dropwise condensation. Our observation of unstable dropwise condensation of steam on a smooth hydrophilic surface shows presence of a several nanometers thick water film between droplets during dropwise condensation. This data matches with previous experimental work in support of film rupture theory. In summary, our results indicate nucleation theory or film rupture theory may be valid for special experimental settings. And, neither of these two theories are a comprehensive theory than can explain the physics of dropwise condensation