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The plateau of Settat is formed by Paleozoic age formations surmounted by a subhorizontal cover made up mainly of Cretaceous sedimentary rocks formed of limestones, sandstones and clays with alternating marly limestones and marls. The study area is characterized by a dry to semi-dry climate, an endorheic hydrographic network that flows into the plain, and is affected by a hydraulic fracturing network of WNW-ESE and NE-SW directions. These factors cause repetitive and cyclical disturbances and disorders recorded on the railway section between Settat and Machraa Ben Abbou and are due to the shrinkage-swelling of the clay formations. The statistical and critical analysis of the defects identified by the device of measuring the geometric parameters of the railway, coupled with an exploitation of the Optical and Radar satellite images, made it possible to refine the geological, hydrological and structural study of the plain studied. These approaches have shown that this hazard has been favored by the existence of recent clayey and swelling formations under the influence by the climatic, hydrological and geological contrasts marked by intense hydraulic fracturing of the zone.

The problems of the stability of the mineral-bearing structure ST2 at 560 m of depth in the east zone of Bou-azzer mine disturbs the advance of the exploitation. The geological and structural study based on field observations and the analysis of core drilling shows the presence of altered and fractured diorite surmounted by cobalt mineralization. Based on the empirical methods of Barton (Q-system) and Bieniawski (RMR) the bed rock is classified as poor quality. The analytical study made it possible to dimension supporting by bow-pieces and bolting. The existence of several types of discontinuities (fault, diaclases and joints) has made the realization of numerical simulation by the finite elements method very difficult. These discontinuities create a network of natural fractures which cut out the blocks in various forms likely to be detached or slip into the excavation, thus encouraging the infiltration of water creating pressure on the massif. The classical studies show their limits in practice for installation of supporting because they must take into account the characteristics of discontinuities. Hence a structural analysis of the massif is essential. The cracking survey of ST2 at 560 m of depth in the east zone of Bou-azzer mine at 560m of depth, and their processing by the DIPS software, showed the existence of three main families of discontinuity NW-SE with a dip of 75SW, NS subverticale and NE-SW with a dip of 57NW, and two families of minor joints NW-SE and NE-SW with successive dips of 40SW and 75SE. The analysis of fracturing surveys allowed us to evaluate the risks of falling blocks and the families of discontinuity responsible for them, and to limit the zones presenting a risk of slip and the families responsible for them. The importance of this study is of knowing how and where to put supporting to be opposed to the risk of fall and tilting of the blocks, caused by the network of discontinuities of the massif.

Water erosion is a natural phenomenon, the severity of which is related to several parameters depending on the raindrop impact, the characteristics of the soil and the level of human intervention. The risk of water erosion occurs in both drainage basins and road and rail slopes. Indeed, this phenomenon can be aggravated causing major gullies and landslides. The PK 94 of the Taourirte-Nador railway line, located in the oriental region of Morocco, whose slopes are formed by silt-clay formations experiencing intense erosion. The Moroccan experience for the slopes protection of water erosion knows the use of several methods in particular; concrete arcades and methods based on biological engineering. The objective is to contribute to this subject by proposing the use of concrete lozenges technique. It have the advantage of reducing both the area at risk of erosion and especially the length of slope which is an important factor in the Revised Universal Soil Loss Equation RUSLE used to quantify the quantities of soil eroded.

Nowadays, many assumptions hold that returning to rammed earth construction could be a solution to the energy challenges of the time. These assumptions are based on the ability of the material to maintain a comfortable indoor temperature regardless of the outdoor climatic variations. However, its influence on the energy performance of buildings remains little explored so far. This paper comes in this order of ideas. It is devoted to study and evaluate the energy efficiency of rammed earth buildings compared to those in concrete structure and masonry envelope. It takes as case study two buildings: one is traditional, entirely built with the technique of rammed earth; the other is constructed of concrete. In order to compare between their performances, we have performed a simulation of the thermal behavior of each by the dynamic thermal simulation software Design Builder.

Throughout the last decades, many authors have published empirical correlations between rock mass classification systems that have arisen from a series of measurements and observations with the special conditions of the work site; this means that the validity of these expressions is strongly dependent on the knowledge of the original data from which they were deduced. Consequently, none of these expressions are universal nowadays. In recent years, the principal corps B3 “CPB3” of IMITER mine area has witnessed massive mining activities involving a large amount of underground excavation, the rock mass characteristics are undoubtedly the essential requirements for empirical design and numerical modeling. Therefore, the research carried out aims to provide a new specific inter-relation between the most widespread Quality Indexes, Bieniawski’s RMR Quality Index, Barton’s Q Quality Index and Palmström’s RMi Mass index utilizing the data gathered from the jointed volcano-sedimentary rock mass of the “CPB3”. The “CPB3” mining level is located in Imiter silver mine, eastern Anti-Atlas, Morocco, at a depth of 500m. A total of 128 rock blocks were examined for the rock mass quality using the three characterization systems, the outcrop mapping was carried out on freshly parallel exposed faces in the horizontal south to north direction. After processing and plotting the in-situ measured data, several equations of the three indexes has been investigated using regression modeling to analyze the obtained results and find the most suitable equation with the highest correlation coefficients. These relationships were then compared with those reported in the literature. The proposed regression models reveal strong correlations between RMR, Q and RMi indexes with high values of accuracy coefficients so that they can be used to estimate the “CPB3” underground rock mass quality for the range of RMR between 30% and 80%. The developed mathematical formulations of the geomechanicalindexes will certainly offer an effective tool to geologist and geotechnical professionals in the decision-making process, preliminary design phase, stability problems and suggestions of the required supporting system and techniques without the expense of more resources or time.

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.Nowadays many semi-empirical methods are used to introduce a proposition to evaluate the liquefaction's potential using the in-situ test results. The objective of this paper is to study their ability to correctly predict the liquefaction potential by modelling our case using finite element methods.The study is based on the data of Cone Penetration Tests experimental results of the Casablanca-Tangier High-Speed Line exactly between PK 116 + 450 and PK 116 + 950 and near of Moulay-Bousselham city. It belongs to the Drader-Soueir basin region which is located in the North-West of Morocco.This region had a specific soil’s formation, the first 50 meters are characterised by the existence of sand layers alternating with layers of clay. These formations are very loose and saturated which suggests the possibility of soil liquefaction.We present and discuss the results of applying the Olsen method [1], the Juang method [2] and the Robertson method [3], in the evaluation of liquefaction susceptibility.Apart from the previous empirical analysis to evaluate the liquefaction potential, numerical modelling is performed in this study.

The study concerns the cartography of the spatio-temporal evolution of the embankments of the road network of the Oued Ouergha watershed using data from the Landsat images on the one hand, and the modeling of soil stability processes. On the other hand. This region experiences an intense destabilization linked to the combination of several natural factors, such as the brutality and the abundance of the precipitations and the outcrop on the marls and limestones of Cretaceous. Human intervention in this vulnerable environment accentuates its fragility through the clearing and degradation of vegetation cover. The analysis of satellite data has shown that the most degraded soils are not necessarily those with the highest rate of erosion over the past fifteen years and that some well-developed soils are unstable areas after clearing and their non-rational exploitation. Human intervention and the choice of road routes sometimes, combined with climate change, remain the most important factors in weakening and increasing the vulnerability of the slopes. The results obtained made it possible to identify and monitor vulnerable zones at the Ouergha watershed scale, where interventions are needed to limit the processes of slope degradation and their impact on the various road access routes in the region.

The amount of household waste produced by the mainly urban population in Morocco continues to increase year after year. Morocco is thus confronted with the problems of storage and disposal of this waste, which are composed largely of organic matter, bio-waste. In the recent past, these wastes have been buried in wild dumps or in old quarries located in areas close to urban centers without any treatment or control. This can constitute significant risks both for public health and the environment and for the future of the socio-economic activities of the country. For which evaluating municipal landfills is vital due to the importance of health and environmental issues and the possibility of contravening environmental and engineering criteria and principles. The present research is conducted using new techniques of approach among others, the analytical hierarchy process AHP, which will allow us to weight and combine all criteria and to classify their respective weights, as well as the use of GIS which will contribute to the evaluation of these criteria in order to determine whether the choice of the current site according to the results of our study meets the requirements of a controlled landfill respecting the environment.

Caused by earthquakes in the marine environment, tsunamis are often of particular violence. Pests, their damage far exceeds those caused by earthquakes earthquakes. In Morocco, seismic sensors in the national network often detect earthquakes in the marine environment. However, specialists minimize their threat given the peculiarity of the Moroccan ocean zone. The latter is characterized by the importance of the length of the faults and the depth of the seismic focus.This work can be considered as a first approach to the study and understanding tsunamis. Although Morocco has known since historical times, earthquakes and tsunamis along its coasts.This preliminary study is mainly intended to show the contribution of the numerical simulation of tsunamis, with a concrete application of the 1755 Tsunami of Lisbon based on the four source zones involving the five potentially tsunamigenic faults that are generally mentioned in the literature for this major event.

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.The northern region in Morocco has an important seismic activity, indeed, this region has been struck during its history by many destructive earthquakes. In this paper, we present and discuss the Mediterranean earthquake, January 25, 2016, saved in ZGH station located in Zeghanghane near of Nador city, Morocco.In this case, we determine the spectral response of the ground motion for ZGH station, and study his influence on the structures as well as make a comparison with the requirements of the Moroccan seismic construction regulations (RPS) 2000 revised in 2011.

The use of finite element analysis has become widespread in geotechnical practice as means of optimizing engineering tasks; it can be easily applied to the treated areas by stone columns, which are a method of improving the soil having low geotechnical properties and likely to deform significantly under load action, by incorporating granular material (commonly called ballast) compacted by remounting passes, so they act mainly as inclusions with a higher stiffness, shear strength than the natural soil. Moreover the stone columns are highly permeable and act as vertical drains facilitating consolidation of the soft soil improving the performance of the foundation. However the characteristics of this granular material influence the behavior of soft soils treated by the stone columns technique, especially: the friction angle, the cohesion, the modular ratio and the constitutive model. The choice of the constitutive model depends on many factors but, in general, it is related to the type of analysis that we intend to perform. Numerical modeling must consider the diversity of the materials nature, the complex geometry of structures-land and the behavior of materials generally nonlinear (permanent deformation). It is a simple and effective alternative to approach the real behavior of soils reinforced by stone columns and the influence of materials characteristics, 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. This paper aims to study the mechanisms of functioning and interactions of stone columns with the surrounding ground, and vis-à-vis the various parameters characterizing the granular material "ballast" and the surrounding soil, which influence the behavior of the improved soil, The paper presents, in the first part, soil conditions and the parameters associated with columns, is then presented 3D finite element analyses, so the parametric study was carried out varying several properties especially granular material properties.

Masonry is often used in the most of reinforced concrete structure constructions as a filling material that is important on structural characteristics. Structural contribution in the calculations was neglected or misunderstood, mainly due to the lack of a practical calculation methods and an appropriate regulatory tool.The analysis of frames filled with masonry is very complex. This complexity is linked from one part to the difference in the nature of elements and its behavior that make up the masonry itself (brick and mortar) and their interaction, and on the other part, for the large dispersion that characterizes the bricks as well as the execution's quality parameters which make it difficult to define reliable criteria for the masonry. The objective of this work is to experimentally highlight the influence of the hollow brick masonry filler, commonly used in Morocco, on reinforced concrete frames subject to lateral stresses, to deepen understanding the seismic behavior of the masonry structures by evaluating the structural performance of a specimen wall. These experimental results will be compared to those found by modeling prototypes, using SAP 2000 software, based on various approaches and models as well as other results deduced from the other researchers. The experimental study was carried out according to standard NF EN 1052-3 on two reinforced concrete frames, of dimensions (2m X 1.6m), the one with the masonry filling, and the other without filling in order to determine the initial characteristic resistance to the shearing of the masonry walls. The obtained results showed that a filling has a beneficial effect on rigidity which can be doubled compared to an empty frame. in the same way the lateral resistance. But this effect is much contrasted; it depends a lot on the characteristics essentially of the materials (bricks and concrete). This is the main reason, which justifies the divergence of the results deduced from the nine models that we used.

The Moroccan road network has a linear of more than 57,000 km divided into national, regional, provincial and unclassified roads. Population growth, the transport of goods and the mobility of people require the construction of new links between regions and the maintenance of existing ones. Indeed, several factors, such as rainfall and floods, can cause enormous damage to existing infrastructure. Among the most at-risk areas is the GHARB region, especially the province of Kénitra, represented in this study by Provincial Road RP4209, which includes flood-prone areas with abundant watercourses, associated with poor type of soil. To mitigate these phenomena and to try to reduce their impacts, in particular on the components of a road, one of the appropriate solutions remains the treatment of soils. This process is increasingly practiced in the construction industry, improves the geotechnical and mechanical characteristics of soils without having to go through the contribution of materials from other regions, all for the purpose of a valuation of materials in place by treatment with lime, different hydraulic binders, or industrial products, which will provide an economic and environmental gain

The swelling phenomenon appears seriously when changing the soil-moisture conditions. The swelling pressure induced by the expansive soil can causes unfavourable problems or instability for the civil structures. So, understanding the soil behavior is considered a valuable work for engineers and consultants in the geotechnical and civil engineering sectors. In reality, the assessment of the swelling pressure of expansive soil depends, first of all, of test conditions related to the change of soil-moisture, as it happens, the influence of the combination “loading-start wetting” and also the unloading process after saturation. To this end, we establish an experimental study on the green clay of Tangier to evaluate the swelling pressure by using oedometer apparatus. Secondly, attention is bore to the combination “initial water content-dry density”, another factor related to the change of the soil-moisture, to show the influence of initial state condition on the swelling pressure.

The Soil and subsoil survey are performed by direct and indirect methods. The direct methods are the investigations of field and laboratory while indirect methods are the geophysical methods. These allow, from one or more physical properties, to find out the underground's structure nondestructively. Geophysical methods for characterizing subsurface have long been used, in geotechnical, hydrogeological and environmental studies. For our study, we used the electrical resistivity's method. 52 geoelectric soundings VES was performed with a mesh of 500 m and electrodes distance between 1000 m and 3000 m. The interpretation of these VES allows the determination of the vertical succession of formations in place. In order to have a lateral facies variation, we used geostatistical methods for having adequate data that can be used in the input file of inversion's code Res2Dinv. The 2D images of the subsoil obtained confirm and complement the results of the correlations of oil drilling that are in this region. Thus, the study area also has a horst and graben structure. This study also allowed us to locate the sandstone formations that extend in two places along a North-South direction.

The soil is generally a heterogeneous material presenting very variable characteristics. In a general way, the main problems related to soils are: low bearing capacity, deformations under static or dynamic loads, large displacements and large settlements of soft soil where the soil moves according to a fixed ground water table. The development of soil mechanics and geotechnical engineering has led to the amelioration of a wide range of soil improvement techniques. These techniques consist in modifying the characteristics of the ground by physical action or by incorporating columnar inclusions made of highly compacted gravel or granular material into the original soil. Stone column is one of the soft ground improvement methods, applicable to a wide range of soil strata and an economical method of support in compressible and cohesive soils. However, there are many difficulties in quantitative analysis of soil column interaction due to the fact that bearing capacity and consolidation behavior of stone column-mat foundation system is affected by various parameters. In the present study, mechanism and various parameters of stone column behavior are investigated by loading tests. Also, tests results are compared to the finite element numerical modeling “Plaxis 2D” (case study: the embankment under the bridge “Moulay Youssef, Rabat/Salé”).