Slope Stability Evaluations by Limit Equilibrium and Finite Element Methods Applied to a Railway in the Moroccan Rif

Since 1930, the analysis of slope stability is done according to the limit equilibrium approach. Several methods were developed of which certain remain applicable because of their simplicity. However, major disadvantages of these methods are (1) they do not take into account the soil behavior and (2) the complex cases cannot be studied with precision. The use of the finite elements in calculations of stability has to overcome the weakness of the traditional methods. An analysis of stability was applied to a slope, of complex geometry, composed of alternating sandstone and marls using finite elements and limit equilibrium methods. The calculation of the safety factors did not note any significant difference between the two approaches. Various calculations carried out illustrate perfectly benefits that can be gained from modeling the behavior by the finite elements method. In the finite elements analysis, the shape of deformations localization in the slope is nearly circular and confirms the shape of the failure line which constitutes the basic assumption of the analytical methods. The integration of the constitutive laws of soils and the use of field’s results tests in finite elements models predict the failure mode, to better approach the real behavior of slope soil formations and to optimize its reinforcement.

Atmospheric Pollution due to Road Traffic Case of the Greater Casablanca Region

In the Greater Casablanca, road transport is the second largest emissions source of gaseous pollutants and particles after the industry [ 1 ]. The emitters are mobile and include different categories of vehicles in circulation, in the road network of the region [2]. Air emissions from road transport considered in this study are the exhaust emissions from combustion of fuel during vehicle movement. This is mainly SO2 （sulfur dioxide）, NOx （nitrogen oxides）, CO （carbon monoxide）, CO2 （carbon dioxide）, SP （suspended particulate） [3], VOC （volatile organic compounds）, benzene, lead Pb and cadmium. These emissions depend mainly on the technology of the vehicle （type, fuel, engine size, and age）, the vehicle speed, the engine temperature and ambient temperature [4].

Geophysics Contribution for the Determination of Aquifers with a Case Study

The determination and monitoring of aquifer formations on the eastern border of Moroccan Gharb basin are very difficult because of their spatial and temporal variation. To delimit these formations, a geophysical survey of 52 geoelectric soundings was performed with a mesh of 500 m and electrodes distance between 1000 m and 3000 m. Geoelectric sections and resistivity maps show a horst and graben structure. The correlation of existing oil drillings shows that the Jurassic and Neogene formations are both affected by normal faults causing Jurassic deposits collapse with local thickening of the Miocene deposits, and reverse faults delimiting tectonic slices due to tension caused by prerifaine nappe advance. This fact confirms the generated structure by the resistivity method. The isobath map of resistant formations's roof show average depths extending from 400 to 800 m for calcareous sandstone that are potential aquifers while oil drillings indicate over 1000 m depths.

A New Shrinkage Curve Model, Applied to Moroccan Clayey Soil

On the basis of the existing relation between the soil’s water content and its structural evolution, we elaborate a new analytical model allowing the analysis of the soil’s shrinkage curve according to the limits of its hydro-structural boundaries. This model was conducted on undisturbed clayey soil at Moulel-Bergui, Morocco.

Evaluation of the Contribution of Aerosols in the Contamination of the Environment in the Greater Casablanca

The Greater Casablanca, like the other large cities, has experienced significant urban and industrial development in recent years, this development has certainly helped develop the productive fabric, generate significant employment opportunities for hundreds of thousands of families, but at the expense of the mobility and quality of the environment particularly those of the air. The deterioration of the air quality affects more and more the population＇s health with significant cost and damage to the community, this study aims to quantify the degree of aerosols pollution damage and also its health effects.

Methodological Approach of Decision Support for the Development Choices of an Abandoned Quarry (The Landfill of Mohammedia-Morocco)

The principal component analysis of the landfill of Mohammedia, was carried out by monitoring and spatiotemporal analysis of a number of physical and chemical tracers (temperature, pH, salinity, conductivity, dissolved oxygen, suspended solids, TOC and metal) of superficial waters during the years 2010-2012. It has, on the one hand, to evaluate several options in situations where no possibility is perfect, and secondly, to visualize the distribution of different individuals (wells), which gave an idea of their similarity relative the measured variables revealed two major groups: The group I is close to the proximal region of the river and landfill and submitted to direct influences of the latter and the group II, with transitional character between wells in Group I, which is characterized by a relatively high TOC showing a deteriorated water quality. And for the potential damage caused by the landfill of the waters of river El Maleh, the identification of suitable rehabilitation plan for this landfill becomes a necessity.

First Determination of Source Parameters of Moderate Earthquakes (4.1 ≤ M ≤ 5.1) in Morocco from Spectral Analysis

Recent installation of an array of broad band seismological stations in Morocco allowed us to study the records of five recent (2005-2008) moderate earthquakes (4.1 ≤ M ≤ 5.1) in order to determine their source parameters (seismic moment, fault slip, rupture area and stress drop) from P-wave spectra. We also studied the older Rissani events of 1992 using teleseismic data. Values of Mo, r, Δu and Δσ are, respectively, 1.1 × 1013 - 6 × 1016 Nm;0.50 - 3.9 km;0.8 - 5.8 cm and 0.3 - 1.49 MPa. The results are in accordance with the seismotectonic and geodynamic setting of Morocco as, for instance, the amount of slip along the faults with respect to the relative displacement of Nubia to Iberia (~4 mm·yr-1) determined from GPS data, taking into account the period of stress accumulation. However, some events show very variable corner frequency and low-frequency amplitude values which lead to considerably higher stress drop and fault slip values, especially at the nearest stations, which may reflect some site effects or uncertainties on depth and take-off angles.