Sökning: "Closed-form solution"

Visar resultat 1 - 5 av 62 avhandlingar innehållade orden Closed-form solution.

1. 1. Efficient Modelling Techniques for Vibration Analyses of Railway Bridges

   Författare :Christoffer Svedholm; Costin Pacoste; Pedro Museros; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Railway bridge; High-speed train; Closed-form solution; Non-proportional damping; Complex mode;

   Sammanfattning : The world-wide development of new high-speed rail lines has led to more stringent design requirements for railway bridges, mainly because high-speed trains can cause resonance in the bridge superstructure. Dynamic simulations, often utilising time-consuming finite element analysis (FEA), have become essential for avoiding such problems. LÄS MER

3. 2. Constitutive Behaviour and Fracture of Adhesive Layers : Inverse Methods and Energetic Balance

   Författare :Svante Alfredsson; Högskolan i Skövde; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; adhesive layer; constitutive behaviour; fracture; energy release rate; shear fracture; mode-mixity; experimental method; inverse solution; multi-material joints; TECHNOLOGY; TEKNIKVETENSKAP; Teknik; Technology;

   Sammanfattning : In the automobile industry, current demands on reduced emissions with maintained or even increased crash worthiness, forces the industry to seek weight-reducing designs. The possibility to use lightweight materials is obviously attractive. At joints, these lightweight materials have to be connected to high-strength or low-cost materials. LÄS MER

4. 3. Stress Effects on Solute Transport in Fractured rocks

   Författare :Zhihong Zhao; Lanru Jing; Ivars Neretnieks; Auli Niemi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fractured rocks; Solute transport; Stress effects; Coupled stress-flow-transport processes; Analytical solution; Particle mechanics model; Fracture surface damage; Discrete element method; Particle tracking method;

   Sammanfattning : The effect of in-situ or redistributed stress on solute transport in fractured rocks is one of the major concerns for many subsurface engineering problems. However, it remains poorly understood due to the difficulties in experiments and numerical modeling. LÄS MER

5. 4. On Model Simplification in System Identification

   Författare :Bo Wahlberg; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Model simplification; System identification;

   Sammanfattning : This report deals with the connection between system identification and model reduction. We propose an identification algorithm that is based on the least squares identification method and either of the model reduction techniques: Frequency weighted truncated balanced realization or frequency weighted optimal Hankel-norm model reduction. LÄS MER

7. 5. Human-structure interaction effect on the dynamic response of footbridges : An analytical and experimental study

   Författare :Daniel Colmenares; Raid Karoumi; Andreas Andersson; Federica Tubino; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; footbridges; dynamics; human induced loads; human structure interaction.; Bro- och stålbyggnad; Structural Engineering and Bridges;

   Sammanfattning : Lightweight, slender and lightly damped footbridges are often susceptible to HumanInduced Loads (HILs) when pedestrian step frequencies coincide with the naturalfrequencies of the structure. For vertical vibrations, this can compromise the serviceabilitylimit state of the system. LÄS MER