Slope instability of open-pit mines has adverse impacts on the overall mine profitability, safety and environment. The slope of an open-pit mine is crucially influenced by the slope geometry, quality of rock mass and presence of geological features and their properties. The objective of this study is to demonstrate a method to select the optimal overall slope angle of open-pit mines according to three design parameters, namely, safety (e.g., probability of instability), productivity (e.g., profit) and mining costs (e.g., cost of removal of overburden). Therefore, this study attempts a hybrid approach in which numerical modelling is integrated with probabilistic analysis to evaluate the stability of an open-pit mine at various overall slope angles. Two-dimensional elasto-plastic finite-element, RS2D, has been used to develop a series of models at different ultimate slope angles employing shear strength reduction technique (SSRT). Li’s point-estimate method of n3 has been invoked in deterministic analysis to tackle the inherent uncertainty associated with host rock mass properties. The results reveal that the mine profitability increases and the cost of overburden removal decreases as overall slope angle becomes steeper. However, the slope stability deteriorates. Therefore, it is highly advisable to combine these three design parameters (e.g., safety, productivity, and cost) together when selecting overall slope angle of open-pit mines.

Cement kiln dust (CKD) produced in a local cement production plant in Assiut Cement Company-Egypt, along with CKD resulting from combustion of cement were utilized as waste materials. These blends were tested for their water requirements for normal consistency, initial setting times, compression and tensile strengths. The materials used in this research are ``untreated'' CKD. It was collected from electrostatic precipitators and ordinary Portland cement (O.P.C). Several specimens were prepared in the laboratory for the compressive strength testing. The specimens were prepared by proportioning sand and CKD according to selected ratios then adding the optimum percentage of water

In this paper, presents of experimental tests carried out on physical and chemical properties of cement kiln dust. Cement kiln dust is considered a one of waste which produced in a local cement production plant production plant Portland cement manufacturing in Assuit Cement Company-Egypt. The main aim of this study is to examine some factors that influence the performance of a strip footing resting on a sandy slope by the utilization with CKD. This study aims also at establishing relationships between the bearing capacity and the CKD percentage and forming a database for future development of a rational design method. The angle of the slope was taken equal to (42o). Laboratory tests on small scale model were carried out. The experimental model was simulated by the finite element method (FEM) using the computer program PLAXIS. The verification of the numerical results by the corresponding experimental results has been done to emphasis the accuracy of the parameters used in the numerical analysis.

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This paper explores a solution to safeguard buried pipes located near constructions in the Al-Bisri region of Assiut Governorate by utilizing the concept of the characteristic damage state. This issue has escalated due to the increasing rate of construction activity near pipelines, resulting in a multitude of legal disputes. This study investigates the behavior of buried pipes when influenced by newly constructed buildings using the finite element method. The paper employs two-dimensional models of a 12-story reinforced concrete building with a raft foundation and a series of piles supporting the buried pipe. In this study, we used the PLAXIS software, a 2D plane strain program, to conduct numerical investigations. The soil was idealized using the Mohr–Coulomb model with a 15-node triangular element, while the piles and structures were idealized with a five-node isoperimetric beam element. The point of contact between the beam and the soil was represented by the interface element. Our research examined the distance between the pipe and the footing edge and the distance between the piles and the footing edge. The finite element model results provided nodal displacements and element straining actions for analysis. The results shed light on the behavior of the sheet pile wall and sewage pipe in various situations. The largest bending moment in the sewage pipe was seen in the absence of piling, in contrast, to pile support at Rx = 0.75. The bending moment in the pipe expanded and always occurred at the same location as Rx rose. The clay layer next to the pipe’s lateral deformation was significantly reduced after piling, with the greatest deformation occurring at Rx = 0.