A nice thing about standards

The paper documents the implementation of automated data exchange process as an alternative to the manual workflow an architect needs to go through if he wants to comply with the EPR and acoustic regulations imposed by recent Flemish standards. This application is able to import specific IFC files and interpret its information. It automatically acquires the information needed and performs the calculations. The results of the calculation are then displayed through a user-friendly interface, to enable a designer evaluate his design and immediately make improvements to his model. This application was tested in a case-study using an exemplary BIM model. The overall functionality of the communication process from BIM to the application is analysed and the resulting concerns are outlined

Fatigue damage identification in threaded connection of tubular structures through in-situ modal tests

The use of threaded connection is a valuable alternative to conventional welding in tubular constructions, e.g. pipelines, drill pipes and deep water risers. Those applications are normally exposed to environmental hazards – wave induced vibrations, temperature changes, etc. – as well as subjected to severe service conditions. A classical way to determine fatigue strength in many engineering situations is to calibrate material models by means of ad hoc designed experiments. Unfortunately, it is very difficult in this case even under laboratory conditions due to complicated stress and strain states in the contacting tapered helical thread surfaces of the connection. Therefore, a classical four-point bending fatigue test setup has been built with a real pipe specimen of 3.75 meter long, consisting of two standard API pipes connected by a threaded coupling, under unsymmetric (non-zero average) load control cycles. A complete vibration study has been carried out based on input-output modal tests for the entire period of the fatigue experiment. Input excitation is due to hammer impact and responses are recorded by accelerometers and by reusable dynamic strain gauges. The measured modal strains from the dynamic strain gauges allow for direct calculation of the modal curvatures, rather than deriving approximately from acceleration information. By comparing the measured modal parameters with those of a numerical model of the same structure in undamaged condition, damage detection, localization in the coupling and quantification are possible. This study leads to the following conclusion of practical use: the recent advancement in modal analysis, i.e. the reference based input-output combined deterministic-stochastic subspace identification, makes it possible to identify the structural modal properties from in-situ modal tests, which are performed while the fatigue test is ongoing. In this way the fatigue test is uninterrupted to avoid the problem of stress and strain disturbances happened in un-reversing load cycles test

Groove design for form fit joints made by electromagnetic pulse crimping

The electromagnetic pulse process can be an alternative for many conventional production processes. It can be used for perforating, cutting, welding, forming and crimping. In this thesis, the latter will be investigated in detail, with the emphasis on tubular joints bearing axial tension and/or torsion loading. To get acquainted with the subject, first a literature study was performed concerning the general principles of electromagnetic pulse crimping. Because a new field shaper had to be designed, literature on this topic was also consulted. Finally, the design and use of grooves in crimp joints was studied. It has been reported that an inner piece (mandrel) with additional grooves in the joining zone significantly increases the strength of a crimped joint [1]. However, the information on electromagnetic pulse crimping with a mandrel with more than one groove is very limited. Therefore one of the main goals of this thesis is to determine an optimal design for a mandrel with two grooves used for axially loaded joints. A combination of finite element simulations and experiments was used to draw preliminary conclusions involving the double groove design. In a later stage torsional joints will be designed and suitable filler materials to realize leak proof joints will be evaluated

Weldability of micro-alloyed high-strength pipeline steels using a new friction welding variant

An innovative welding method for fully automatic joining of pipelines has been developed. The proposed welding procedure is a variant of the conventional friction welding process. A rotating intermediate ring is used to generate heat necessary to realise the weld. The working principles of the welding process are described. The weldability of the micro-alloyed high-strength pipeline steel API-5L X65 is experimentally investigated. It was found that the new welding process is suitable for joining this material. When welding with a sufficiently low heat input, a high weld quality is obtained. Under these circumstances the weld strength, ductility and impact toughness are high and fulfil the requirements of the commonly used standard EN 12732 for joining pipes

Friction welding of ceramics to metals

This paper discusses the progress in a master thesis about friction welding of ceramics to metals. An existing friction welding machine has to be adapted for the experimental part of this research. The required capabilities of this machine are discussed in this paper. As an introduction, a general explanation about friction welding is given. The results of a literature survey on friction welding of ceramics to metals are discussed. The aim of this survey was to determine the process parameters required to obtain a good weld quality. It became clear that few literature exists on friction welding of these materials and that the cited values for the process parameters vary widely. Based hereon, a range of process parameter values was used to make certain design choices. Because a laboratory machine is aimed at, it has to be able to function at varying settings of the process parameters, including testing at higher rotational speeds. Finally, process windows illustrating sound combinations of friction pressure and specimen diameter are calculated. The design choices entail certain restrictions on the capabilities of the machine. These restrictions define the boundaries of the process windows

Finite element modelling of several physical engineering problems

This paper presents the application of the Finite Element Method (FEM) to a wide range of physical engineering problems and analysis types. It summarises some of the research works carried out by the author using FEM. The types of analysis, which are coved in this paper, include linear and non-linear stress analysis, heat transfer analysis, diffusion analysis, coupled thermal-stress and coupled diffusionstress analysis, fracture mechanics analysis and modelling of macro-cracks, fatigue damage initiation and crack propagation analysis, modal analysis, transient dynamics analysis and traffic flow analysis.This paper presents the application of the Finite Element Method (FEM) to a wide range of physical engineering problems and analysis types. It summarises some of the research works carried out by the author using FEM. The types of analysis, which are coved in this paper, include linear and non-linear stress analysis, heat transfer analysis, diffusion analysis, coupled thermal-stress and coupled diffusionstress analysis, fracture mechanics analysis and modelling of macro-cracks, fatigue damage initiation and crack propagation analysis, modal analysis, transient dynamics analysis and traffic flow analysis.C