Khadija Baba

Use of the Method of Concrete Lozenges to Strengthening the Slopes Stability: Assessment of the Safety Factor by the Finite Element Method

The major problem of unsaturated slope is the variation of their volumetric water content which is an important factor in the variation of mechanical parameters of soils into the subsurface. It can also influence the soil shear strength; consequently several methods were proposed to improve the unsaturated slope stability including the concrete lozenges technique. It is a new technique used to protect slopes. It constituted a non-continuous mesh mask on the slop, having the effect of collecting and transporting runoff water on the slope. Using the finite element method, the objective of this paper was to study both how the value of soil volumetric water content and the safety factor changed by the use of this new technique. Indeed, the safety factor is <1 for the shallow soil and increases with depth. Simulation and calculation results demonstrated that the proposed technique is capable of making the amount of soil masse affected, less than 1 m.

The Influence of Spectral Responses on the Structures Heights

The earthquakes are abrupt and sudden, and, in few seconds, they can lead to huge casualties. Nowadays, several approaches can be used to better know the seismic movement than we can expect when and where will have an earthquake. These approaches kind, always begins with a full study of the seismic action: the seismic birth, the wave formation and propagation, accelerometers and associated spectrum representation, etc.

Modeling Landslides by the Finite Element Method: Application to an Embankment on a Railway in the Moroccan Rif

Slope instability is one of the problems that often affects the stability of civil engineering infrastructure. These unstable slopes have often led to excessive damage resulting in high budgets to maintain these infrastructures.

The Liquefaction Potential of Sandy Silt Layers Using the Correlation Between Penetrometer Test and SPT Test

Liquefaction is a hazardous and temporary phenomenon by which a soil saturated with water loses some or all of its resistance. The undrained conditions and a cyclic load increase the pores water pressure inside the soil and therefore a reduction of the effective stress.

Numerical Simulations of Ground Improvement Using Stone Columns in “Bouregreg Valley”

The soil is generally a heterogeneous material with very variable characteristics. Soil’s main issues are reflected through low bearing capacity and significant deformations (settlement) under loads. For Geotechnical experts, such problems present a challenge in many Moroccan regions like Rabat (Bouregreg Valley) and the northern regions. To overcome these defects, stone columns are used as a soil improvement technique to reduce settlement and to increase the foundations’ bearing capacity on soft clay soil. The benefits arise from the fact that there is a partial replacement of the compressible soil by a more competent material (compacted stone aggregates). Moreover the stone columns are highly permeable and act as vertical drains facilitating the soft soil’s consolidation and improving the foundation’s performance. Numerical modeling is a simple and effective method to approach the real behavior of soils reinforced by stone columns. It allows settlement analysis, lateral deformation, vertical and horizontal stresses in order to understand the behavior of columns and soil. It also has the advantage of integrating the settlements of the underlying layers, especially those of least resistance. The aim of this paper is to study the numerical simulation’s results. The properties of the soft soil correspond to “Bouregreg valley”-soil. This paper is structured as follows: the first part provides the soil conditions and the parameters related to columns and the second part presents 3D finite element analyses that study the stone columns’ performance. These 3D analyses aim to clarify the most important parameters, the influence of the constitutive models and the column geometry. The study also shows the mechanisms of functioning and interactions of stone columns vis-a-vis the various parameters characterizing the granular material “ballast” and the surrounding soil.