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Partitioned analysis is a method by which sets of time‐dependent ordinary differential equations for coupled systems may be numerically integrated in tandem, thereby avoiding brute‐force simultaneous solution. The coupled systems addressed pertain to fluid—structure, fluid—soil, soil—structure, or even structure—structure interaction. The paper describes the partitioning process for certain discrete‐element equations of motion, as well as the associated computer implementation. It then delineates the procedure for designing a partitioned analysis method in a given application. Finally, examples are presented to illustrate the concepts. It is seen that a key element in the implementation of partitioned analysis is the use of integrated, as opposed to monolithic software.

This paper aims to present an adaptive approach of the generalized finite element method (GFEM) for transient dynamic analysis of bars and trusses. The adaptive GFEM, previously proposed for free vibration analysis, is used with the modal superposition method to obtain precise time-history responses.

The adaptive GFEM is applied to the transient analysis of bars and trusses. To increase the precision of the results and computational efficiency, the modal matrix is responsible for the decoupling of the dynamic equilibrium equations in the modal superposition method, which is used with only the presence of the problem’s most preponderant modes of vibration. These modes of vibration are identified by a proposed coefficient capable of indicating the influence of each mode on the transient response.

The proposed approach leads to more accurate results of displacement, velocity and acceleration when compared to the traditional finite element method.

In this paper, the application of the adaptive GFEM to the transient analysis of bars and trusses is presented for the first time. A methodology of identification of the preponderant modes to be retained in the modal matrix is proposed to improve the quality of the solution. The examples showed that the method has a strong potential to solve dynamic analysis problems, as the approach had already proved to be efficient in the modal analysis of different framed structures. A simple way to perform h-refinement of truss elements to obtain reference solutions for dynamic problems is also proposed.

The full time response of a space frame under impact loading perpendicular to the frame plane is discussed. Theoretical solutions and experimental results are presented and compared. A space frame clamped at its two ends is loaded by a 0.22 lead bullet that hits a mass in the middle of the transversal beam of the frame. The loading time is about 40 to 60 ?sec and the impact impulses in experiment from 0.5 to 1 Ns. The time response of this frame can be divided into four phases where different physical effects are dominant: (a) the ‘loading’ phase where elastic wave motion dominates the time response. Because of the high impact impulses, plastic deformation occurs in the vicinity of the mass and must be included in a theoretical model. The influence of reflections at the corners on the time response is shown; (b) the ‘evolution’ phase. Within this phase, a plastic collapse mechanism develops. Most of this phase is dominated by elastic deformation but local plastic deformations beside the mass are also present. Because many reflections at the corners and the clampings occur within this phase, a modal analysis method is used to predict time histories; (c) the ‘plastic’ phase with plastic zones at the clampings. This phase sets in after the bending wave reaches the clampings. It is characterized by plastic deformation near the clampings and elastic deformation of the other parts of the frame. We used a modal analysis including plastic ‘modes’ to get accurate results; (d) the ‘elastic vibration’ phase.

This paper aims to present a fast and effective approach to tackle complex fluid structure interaction problems that are relevant for the aeronautical design.

High fidelity computer-aided engineering models (computational fluid dynamics [CFD] and computational structural mechanics) are coupled by embedding modal shapes into the CFD solver using RBF mesh morphing.

The theoretical framework is first explained and its use is then demonstrated with a review of applications including both steady and unsteady cases. Different flow and structural solvers are considered to showcase the portability of the concept.

The method is flexible and can be used for the simulation of complex scenarios, including components vibrations induced by external devices, as in the case of flapping wings.

The computation mesh of the CFD model becomes parametric with respect to the modal shape and, so, capable to self-adapt to the loads exerted by the surrounding fluid both for steady and transient numerical studies.

This chapter reviews three main issues in the interactions between air transport and high-speed rail (HSR) in China, namely the interaction between low-cost carriers (LCCs) and HSR, HSR speed effect on airlines, and airline–HSR integration. Studies on these three aspects of airline–HSR interactions have yet been well reviewed, and our chapter aims to fill in this gap. In this chapter, we comprehensively survey literature on the topics, especially studies on Chinese markets that have recently witnessed major HSR developments (and have planned further large-scale HSR expansion in the coming years). Our review shows that, first, compared to full-service carriers, LCCs face fiercer competition from HSR. However, the expansion of HSR network in China can be better coordinated with LCC development. Second, HSR speed exerts two countervailing effects on airline demand and price (the “travel-time” effect and “safety” effect, respectively). Specifically, an HSR speed reduction can have a positive effect on airlines due to longer HSR travel time, but a negative effect on airlines due to improved perception on HSR safety. Third, airline–HSR integration can be implemented through cooperation between airlines and HSR operators and through co-location of airports and HSR stations and can have important implications for intermodal transport and social welfare.

Structural stress and strain in the key components of aircraft structure is important for structural health monitoring and strength assessment. However, the measure of dynamic strain is often difficult to implement because of the complex test equipment and inconvenient measure points, especially in flight test. This study aims to propose an algorithm of dynamic strain estimation using the acceleration response in time domain to simplify the measure of dynamic strain.

The relationship between the strain and acceleration response is established through the sinusoidal response or modal analysis, which is insensitive to the excitation position and form. A band-pass filter is used to obtain the modal acceleration response, and a filter frequency band selection method is proposed. Then, the dynamic strain at the concerned points can be estimated based on the modal superposition principle.

Simulation and experiment are implemented to validate the applicability and effectiveness of the strain estimation method. The estimated strain results agree well with numerical simulation as well as the experimental results. The simplicity and accuracy of the strain estimation method show practicability for dynamic strength and fatigue analysis in engineering applications.

An algorithm of dynamic strain estimation using the acceleration response in time domain is developed. A band-pass filter is used to obtain the modal acceleration response, and a filter frequency band selection method is proposed. The dynamic strain at the concerned points can be estimated based on the modal superposition principle.

Purpose – The objective of this chapter is to draw the attention of policy makers in the fields of urban planning and transport in China to the importance of developing more balanced multi-modal transport systems and the corresponding land-use patterns to support transport systems, particularly walking and cycling in order to address the issues arising from the dense, highly mixed land-use pattern in many Chinese cities. This will help to reverse current planning practices which give car-oriented development top priority and less consideration of walking and cycling.

Methodology – Statistical methods have been applied to analyse modal split in some cities in Japan, Beijing and Shanghai using travel surveys, plus analysis of the experience of policies in various cities around the world, especially in terms of the relationship between the modal shares for public transport and car. Door-to-door travel times have been analysed for Shanghai to understand the potential of cycle or e-bicycle in a dense urban environment.

Findings – The change in travel modal split in Beijing in recent years suggests that simply encouraging public transport cannot control use of car. The data from Japan also shows that normal bus services cannot compete with the car, but it is clear that people will travel less by car if there is a high non-motorized share in the city. Because of the low density of the metro network, the door-to-door travel speed by metro is not as fast as is often imagined, due to the long off-metro time. The people who use metro are often not the people who live very close to metro stations, but some distance away, so improving the connection to the station by cycle or e-bicycle could greatly reduce the total travel time by metro.

Research limitations and implications – More analyses should be conducted in medium-size and small-size cities in China, where the local capacity is low and there is great potential to travel by walking and cycling, but only after clear guidance and policy instruments have been provided by higher authorities.

Practical and social implications – There is still a relatively high share of non-motorized travel in China. Many cities still have extensive cycle infrastructure established under the State Code of Urban Road Transport Planning issued in 1995. Encouraging non-motorized transport systems is not only possible, but also good for the environment, and contributes to travel efficiency and social inclusion.

Originality – This chapter is the summary of several original research studies using primary survey data, encouraging public transport in China. This is the first research to show the great potential of non-motorized mode for controlling car use and improving urban mobility in China. It is also the first chapter to point out the integration of multi-modal transport systems with the corresponding built environment in China.