Laidi Zahiri

• Doctor of Mechanical Engineering
• Head of Department at Université Hassan II Casablanca

External corrosion is a significant issue that can lead to ruptures in long-distance liquid transportation facilities such as pipelines. Highlighting the need for regular monitoring of their condition, which can compromise their integrity and safety. Three types of external corrosion defects were studied since it is necessary in some to prioritize...

This article proposes a new approach to optimize the cooperation of three robots for the assembly and welding of two parts using the LM algorithm of artificial intelligence. The proposed method aims to enhance the robots' cooperation and ensure a precise and efficient assembly and welding process. The simulations are conducted using Matlab/SimMecha...

This paper proposes an inverse dynamics solution for two cooperative robots in a low depth milling application, by using the Levenberg-Marquardt algorithm. The objective is to achieve precise and coordinated control of the motions of the two robots working cooperatively to perform a milling task on a part. The proposed solution involves modeling th...

This study explores the intricacies of employing two cooperative robotic manipulators for milling operations. Path planning, tool feed rate regulation, and cutting force management constitute essential elements in the milling process executed by these two collaborative robots. The two cooperative robots' milling process requires the coordination of...

This work highlights the use of artificial intelligence (AI) in fracture mechanics, in particular to solve complex problems such as the fracture of a corroded pipeline subjected to both internal pressure and axial compressive stress. The paper describes the use of artificial neural networks (ANN), a popular technique in AI, to replace the empirical...

Phase change materials (PCMs) hold promise for enhancing building energy efficiency. Smart walls with PCMs effectively control indoor temperatures, reducing heating and cooling energy use. This study examines five PCM configurations within a smart wall, including a reference wall, PCM1 wall, PCM2 wall, a dual PCM wall, and a novel configuration in...

Polymer nanocomposites reinforced with nanofillers are widely used in different engineering fields, due to their attractive mechanical properties. In this study, the static response of polymer nanocomposite beams (PNB) reinforced with functionally graded single-walled boron nitride nanotubes (FG-SWBNNT) and resting on elastic foundations (EF) is in...

The thermal insulation of buildings based on ecological materials resets the excellent solution to decrease the impact of inorganic materials on the environment, using materials of biological origins, such as Durian, Bagasse, Date Palm, Pineapple Leaves, Wood fibers, etc. With their low intrinsic energy, they can improve the quality of the environm...

Steel pipes used for conveying pressurized fluids are often defective due to manufacturing error, improper handling or construction materials. These defects may be in the form of cracks which propagate until the mechanical structure is fractured, or in the form of dent which produce a local concentration of stress and thus weaken the structure. In...

Pipelines are commonly used to transport energy over long distances. If this structure is subjected to an internal pressure of variable amplitude loading, such as water hammer waves, the structural damage caused by the presence of a defect can be exacerbated. Previous research by the authors resulted in the development of finite element models to e...

Snail shell particles are used to reinforce a thermoplastic matrix which is Polypropylene (PP) widely employed in the plastic industry. This bio filler has several interesting properties offering the bio-composite studied more thermo mechanical advantages, low density and lower cost in addition to meet current requirements of sustainable developmen...

The current challenge in the composites field is to obtain lighter and less expensive materials in addition to solve environmental and sustainable development problems. The use of bio load composites is a solution to these industrial requirements. Among the loads which have attracted the attention of researchers in last years, we will cite animal h...

Pipelines are a highly dependable method of transporting fluids under pressure. These pipelines, like any mechanical structure, can have flaws. The severity of these defects can be exacerbated if the pipeline transports corrosive fluids. The primary objectives of this paper are to compare the various types of cracking defects that can occur in a lo...

Steel pipes used for conveying pressurized fluids are often defective due to manufacturing error, improper handling or construction materials. These defects may be in the form of cracks which propagate until the mechanical structure is fractured, or in the form of dent which produce a local concentration of stress and thus weaken the structure. In...

Pipelines used for the transport of pressure fluids may have defects due to design error, external impact, or corrosion. These failures take the form of cracks that propagate until the mechanical structure is broken. A comparative study of three main causes of pipe failures (Dent defect, crack welding defect and corrosion defect) was presented and...

The radiative cooling is a natural phenomenon, which allows rejecting the heat energy stocked by earthly objects by radiation outward, through the atmosphere-window (8-13µm). In this work, a numerical modeling of a photovoltaic thermal panel was evaluated by using the TRNSYS simulation software. The numerical model was validated by comparing the PV...

The pipes used for the transport of fluids under pressure can show defects due to a manufacturing error or because of corrosion or an impact with a foreign body. These defects appear in the form of cracks, which propagate until the fracture of the mechanical structure. This paper deals with stress corrosion defects in the steel pipe API X52 and, in...

Increased recycling of PVC has become a requirement in industrial and scientific research level. Several studies will be realized. To confirm and check the recycled materials performance, it will be important to go through numerical modeling, which consists not only in validating the results of the experiments, but also in predicting what happens w...

Robotics is a very dynamic field, which has been evolving diligently in these recent years. The pandemic disease hitting the world actually is accelerating significantly this development of robotics. The robot is a main factor that helps to ensure the distanciating in order to minimize the spread of this disease (Covid-19).Our contribution concerns...

During service, oil and gas pipelines may be exposed to cyclical loads during service, which may lead to a structural failure. Failure is due in most cases to cracks in the structure. Mechanics of the propagation of surface cracks pose a serious challenge and, therefore, models are required to help analyze it. In this study, a nonlinear model is pr...

The radiative cooling is a natural phenomenon, which allows rejecting the heat energy stocked by earthly objects by radiation outward, through the atmosphere-window (8–13 µm). In this work, a combination of the solar heating and the radiative cooling technologies by using a photovoltaic-thermal collector (PVT) has been investigated. A numerical mod...

La Total Productive Maintenance (TPM) est une de marche pour ame liorer continuellement le rendement des ressources de production [1-2]. Elle inte gre le management, l'e coute et la responsabilisation des ope rateurs. La TPM a pour objectifs de perfectionner le taux de rendement synthe tique (TRS) [3], de rendre le processus de fabrication et les e...

Les conduites utilisées pour le transport de fluides sous pression peuvent présenter des défauts dûs à une erreur de fabrication ou à un impact avec un corps étranger ou à une corrosion. Ces défauts se présentent sous forme de fissures [2] qui se propagent jusqu'à la rupture de la structure mécanique. Ce papier traite les défauts de corrosion sous...

Wind energy is natural and renewable like solar energy; it is an inexhaustible source. Morocco, like many other countries in the world, is embarking on a new strategy aimed at improving its production of electricity from non-polluting sources. In this article, we aim to evaluate the wind potential in the region of Mohammedia by relying on statistic...

Water hammer pressure wave may occur in pipelines transporting fluids when a sudden change in flow occurs. To model this phenomenon, the method of characteristic technic is used to solve mathematical equations describing the transient flow in the pipe considering the transportation of four different fluids. The results of pressure variation are the...

The pipelines used to transport pressurized fluids may contain defects due to manufacturing errors or impacts with a foreign body. These defects can occur in the form of cracks that propagate until the rupture of the mechanical structure. These cracks can be present in the three materials constituting the welded pipe (base metal, welding metal and...

Steel pipelines that transport pressurized fluids can contain a dent defect which is a permanent deformation of the outer wall due to an impact with a foreign body. This defect induces a high local stress concentration. This paper presents an optimized numerical model based on finite elements to assess the stress concentration factor around constra...

This paper presents a study of the effect of plain dents caused by accidental impact on the integrity of steel pipelines. The objective of the work is to assess the effect of dent configuration (constrained and not constrained) and dent shape (spherical, transverse and longitudinal) on the harmfulness of the defect. The main elements of an experime...

- Déterminer numériquement la distribution des contraintes par la MEF dans un tube métallique sous pression interne uniforme présentant un défaut du type fissure de forme semi-elliptique. - Evaluer le facteur d’intensité de contrainte pour différentes dimensions de fissure et sous différentes pressions internes. - Conclure quant à l’effet de la pr...

This paper is a contribution to the evaluation of the stress concentration factor using finite element method in dented pipes subjected to internal cyclic pressure. Various approaches for determining the stress concentration factor (Kt) are presented: two numerical approaches in the elasto-plastic range and one in the elastic range. A numerical pro...