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"This book provides a state-of-the-art review of the fail-safe and damage tolerance approaches, allowing weight savings and increasing aircraft reliability and structural integrity.The application of the damage tolerance approach requires extensive know-how of the fatigue and fracture properties, corrosion strength, potential failure modes and non-destructive inspection techniques, particularly minimum detectable defect and inspection intervals. In parallel, engineering practice involving damage tolerance requires numerical techniques for stress analysis of cracked structures. These evolved from basic mode I evaluations using rough finite element approaches, to current 3D modeling based on energetic approaches as the VCCT, or simulation of joining processes. This book provides a concise introduction to this subject."

"This textbook provides a step-by-step approach to numerical methods in engineering modelling. The authors provide a consistent treatment of the topic, from the ground up, to reinforce for students that numerical methods are a set of mathematical modelling tools which allow engineers to represent real-world systems and compute features of these systems with a predictable error rate. Each method presented addresses a specific type of problem, namely root-finding, optimization, integral, derivative, initial value problem, or boundary value problem, and each one encompasses a set of algorithms to solve the problem given some information and to a known error bound. The authors demonstrate that after developing a proper model and understanding of the engineering situation they are working on, engineers can break down a model into a set of specific mathematical problems, and then implement the appropriate numerical methods to solve these problems."

"This book provides a concise discussion of fatigue crack growth (FCG) failure and lifing analysis methods for metallic aircraft structures and components. After a reasonably concise historical review, surveys are made of (i) the importance of fatigue for aircraft structural failures and the sources of fatigue nucleation and cracking, (ii) contemporary FCG lifing methods, and (iii) the Quantitative Fractography (QF) required for determining the actual FCG behaviour. These surveys are followed by the main part of the book, which is a discussion, using case histories, of the applicabilities of Linear Elastic Fracture Mechanics (LEFM) and non-LEFM methods for analysing service fatigue failures and full- and sub-scale test results. This discussion is derived primarily from the experiences of the Defence Science and Technology Group in Melbourne, Australia, and the Netherlands Aerospace Centre, Marknesse, the Netherlands."

"This book deals with the most recent numerical modeling of adhesive joints. Advances in damage mechanics and extended finite element method are described in the context of the finite element method with examples of application. The book also introduces the classical continuum mechanics and fracture mechanics approach and discusses the boundary element method and the finite difference method with indication of the cases they are most adapted to. At the moment there a no numerical technique that can solve any problem and the analyst needs to be aware of the limitations involved in each case."

"ABSTRACTThe development and extension of large cities creates a need of multiple shallow tunnels in the soft ground of built areas. Excavating a tunnel generates ground displacements and deformations which can affect existing buildings and services in urban sites and can lead to unacceptable damages. Prediction of the ground settlement caused by the tunnel excavation has been a major engineering challenge. A numerical simulation using finite element method was implemented in the aim of developing a procedure for forecasting the movement induced by tunneling. This study describes the modelling procedure, comparing one procedure in a complete stages of modelling (called phases modelling) taking into account different phases simulating the different kinds of interaction between the tunnel and the soil (deconfinement, lining installation, pore pressure applied on the lining, and weight of the lining) and one in a simple way called `deconfinement modeling', simulating the excavation using a stress decrease vector exerted on the excavation boundary in the opposite to the initial ground stress described by a scalar parameter A. (the deconfinement rate). A shallow lined tunnel is analyzed in a two dimensional analyses, and observations are made for the settlement at the surface and at the tunnel crown, the deformations of the tunnel opening, and the stress path around the tunnel. Comparison is conducted using two soil models : the Mohr-Coulomb model and the CJS model. Observations of the results and comparison with the experimental data demonstrate that the deconfinement modeling is adequate for the analyses of settlement induced by tunneling only if a good modeling of the soil behavior is considered."

"This book presents new methods of numerical modelling of tube heat exchangers, which can be used to perform design and operation calculations of exchangers characterized by a complex flow system. It also proposes new heat transfer correlations for laminar, transition and turbulent flows. A large part of the book is devoted to experimental testing of heat exchangers, and methods for assessing the indirect measurement uncertainty are presented. Further, it describes a new method for parallel determination of the Nusselt number correlations on both sides of the tube walls based on the nonlinear least squares method and presents the application of computational fluid dynamic (CFD) modeling to determine the air-side Nusselt number correlations. Lastly, it develops a control system based on the mathematical model of the car radiator and compares this with the digital proportional-integral-derivative (PID) controller. The book is intended for students, academics and researchers, as well as for designers and manufacturers of heat exchangers."

"ABSTRAKPenelitian ini mencoba untuk membuat model numeik dan memilihparameter yang sesuai dari data eksperimental dari sistem angkur pada betonpada tahun 2007 di LGCIE INSA Lyon. Dalam penelitian ini menggunakan metodelemen hingga dengan software CAST3M yang mana elemen yang digunakan 2D.Ada dua elemen penting, pertama elemen beton berupa QUA4 dan elemen bajaterbentuk dari elemen BARR. Rangkaian elemen ini terbentuk dari 3 ukuran untukmelihat konvergensi dari perhitungan.Hasil ditunjukkan pada kurva gaya-perpindahan dan diagram teganganregangan.Hasil gaya maksimal yang muncul dekat satu sama lain yaitu 251.25-258.62 kN dan juga perpindahan maksimum ialah 12mm. Angkur pada beton iniruntuh pada baja sesuai dengan hasil eksperimental.

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ABSTRACTThis internship wants to try building a model of numeric and choice theright parameter from the experimental data of anchor system in concrete in 2007at LGCIE INSA Lyon. It uses the finite element method in software CAST3Mwhich the elements are in 2D. There are two elements important, firstly concreteelement is taken from QUA4 and after for steel element is formed by elementBARR. The mesh is formed in 3 sizes for regarding the calculation convergence.Results are shown in force-displacement curve and stress-deformationdiagram. The maximum forces which appear are close to each other, that are251.25-258.62 kN and also the maximum displacement are 12mm. The concreteanchor is failed by shank fracture that is similar with the results of experimental."

"Mengukur tingkat kerusakan struktural akibat gempa telah dipelajari oleh banyak peneliti karena sulit untuk memastikan apakah struktur bangunan yang dirancang untuk bertahan hidup. Dalam penelitian sebelumnya, metode deteksi kerusakan struktural menggunakan frekuensi alami untuk mengindikasikan kerusakan. Namun, metode ini tidak spesifik secara spasial, juga tidak sensitif terhadap kerusakan. Dengan demikian, indeks kerusakan diperkenalkan sebagai alat untuk mengukur kerusakan pada skala tertentu dari nol hingga satu. Di antara berbagai jenis indeks kerusakan, indeks kerusakan Park-Ang digunakan.Model struktur bangunan yang akan dianalisis adalah struktur baja dengan sistem rangka yang diperkuat secara eksentrik. Sistem EBF memiliki karakteristik luar biasa yang memiliki ketangguhan energi gas buang yang tinggi dan kekakuan yang cukup untuk mencegah tekuk. Ini memiliki karakteristik saat memegang bingkai dan bingkai yang diperkuat secara konsentris.Model 2D bangunan EBF dengan variasi jumlah cerita (satu, tiga dan lima cerita) diidentifikasi tentang perilaku, indeks kerusakan dan frekuensi alami. Perilaku bangunan EBF diidentifikasi dengan mengamati analisis push-monotonik dan semi-siklik. Indeks kerusakan struktur bangunan EBF diidentifikasi menggunakan program OpenSees. Selanjutnya, frekuensi alami yang juga mengukur tingkat kerusakan diidentifikasi menggunakan SAP2000. Dengan menentukan indeks kerusakan dan frekuensi alami, tingkat kerusakan dapat diidentifikasi dan juga korelasi antara keduanya dapat diamati.

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Measuring the level of structural damage due to an earthquake has been studied by many researchers because it is difficult to ascertain whether the structure of the building that is designed to survive. In previous studies, structural damage detection methods use natural frequencies to indicate damage. However, this method is not spatially specific, nor is it sensitive to damage. Thus, the damage index was introduced as a tool to measure damage on a specific scale from zero to one. Among the various types of damage index, Park-Ang damage index is used.

The building structure model to be analyzed is a steel structure with an eccentrically reinforced frame system. The EBF system has exceptional characteristics that have high exhaust energy toughness and enough stiffness to prevent buckling. It has the characteristics of a moment holding frame and concentrically reinforced frame.

2D models of EBF buildings with variations in the number of stories (one, three and five stories) identified about behavior, damage index and natural frequency. The behavior of EBF buildings is identified by observing push-monotonic and semi-cyclic analyzes. The EBF building structure damage index was identified using the OpenSees program. Furthermore, natural frequencies that also measure the level of damage are identified using SAP2000. By determining the damage index and natural frequency, the level of damage can be identified and also the correlation between the two can be observed."

"Tiang pancang spun pile merupakan jenis dari tiang pancang yang paling sering digunakan di Indonesia. Sebagai salah satu elemen struktur, spun pile memiliki fungsi yang sangat penting dalam memastikan bangunan dapat berdiri sesuai dengan rencana yang diinginkan. Rencana ini berkaitan dengan rencana dari perilaku struktur ketika terdapat beban yang bekerja, terutama ketika terjadi beban gempa. Hal ini diperlukan karena struktur tidak dapat secara terus menerus menahan gaya yang terjadi pada tiap elemen. Ketika diberikan pembebanan, maka struktur akan mengalami displacement yang mengakibatkan adanya deformasi. Deformasi ini dapat membuat struktur mengalami kerusakan, dimana kerusakan (damage) ini dapat bersifat mikro maupun makro. Apabila kerusakan yang terjadi masih bersifat mikro, maka struktur masih dapat kembali ke bentuk semula. Sedangkan ketika terjadi kerusakan makro, maka pada umumnya akan terjadi crack yang mengakibatkan penurunan kekuatan dari struktur. Selain itu, pada kondisi ini struktur akan berdeformasi secara permanen dan tidak dapat kembali ke bentuk semula. Oleh karena itu, penguji akan melakukan analisis pushover terhadap spun pile untuk melihat bagaimana perilaku damage yang terjadi dengan menggunakan finite element.

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Spun pile is the most commonly used type of pile in Indonesia. As one of the structural elements, spun pile has a very important function in ensuring that the building can stand according to the desired plan. This plan relates to the plan of the structure's behavior when there are working loads, especially when earthquake loads occur. This is necessary because the structure cannot continuously withstand the forces that occur in each element. When given loading, the structure will experience displacement which results in deformation. This deformation can make the structure damaged, where this damage can be micro or macro. If the damage that occurs is still micro, then the structure can still return to its original form. Meanwhile, when macro damage occurs, cracks will generally occur which result in a decrease in the strength of the structure. In addition, in this condition the structure will be permanently deformed and cannot return to its original shape. Therefore, the examiner will conduct a pushover analysis of the spun pile to see how the damage behavior occurs using finite element."