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Reduced models for dynamic analysis of high-speed railway bridges

Today a dynamic analysis is often performed with the use of advanced finite element software. An advanced model normally produces precise results. Analyzing these large models of bridges is however time consuming and a detailed description of the geometry, supports and material properties must be known. In an early stage of a project a reduced model could significantly reduce the time needed to perf

Analysis of Settlements of Test Embankments During 50 Years - A Comparison Between Field Measurements and Numerical Analysis

This report is dealing with time dependent settlements calculated with numerical methods and subsequent comparisons with field measurements. The numerical computations in this report have been performed using Plaxis, a two-dimensional numerical program based on the finite element method. Plaxis is very practical for solving complex geotechnical problems involving settlements or slope stability.

Bärförmåga hos aluminiumprofiler för glasfasader

The work presented in this thesis deals with investigation of methods to evaluate simultaneous moment and normal force capacity for symmetrical and unsymmetrical thin walled aluminium beams. The beams are supplied by Sapa Building System AB and is used in their glass facade system SFB 4150. The system is constructed in a way that makes it possible to make large glass facades. It is then of interes

Finite Element Modeling of Rubber Bushing for Crash Simulation - Experimental Tests and Validation

Until recently, the general level of detail in full car crash models has not allowed a physical modeling of rubber bushings with solid elements. This is partly because of the difficulty in modeling the complex characteristic of rubber, but also due to limited understanding of the mechanical properties of rubber materials. The main focus of this Master’s thesis project is to develop a new and im

Grävpålar - Dimensionering, utförande och användningsområden

Foundations of buildings and structures are laid with various methods, both deep and shallow foundations. Piling is the most common method of deep foundations while spread footings are often used in shallow foundations, especially in buildings with column frame. An alternative is to use a composite pile foundation where piles and spread footings or piles and a base slab are used to carry the loads

Momentreduktion i spontvägg

Examensarbetet behandlar fenomenet momentreduktion. Reduktionen uppstår då en spontvägg deformeras och krafterna i jorden omfördelas. I arbetet har fyra olika spontdimensioneringsmetoder behandlats som på olika sätt leder till ett dimensionerande moment. Tre av dessa är handberäkningar och den fjärde är en jämförande beräkning som görs i finita elementprogrammet PLAXIS. Två av handberäkningsmetThe thesis deals with the phenomenon of moment reduction. The reduction occurs when a sheet pile wall deforms and forces of the soil are redistributed. Four different methods of designing sheet pile walls are treated that in different ways lead to a design moment. Three out of these design methods are made by hand calculations and the fourth is a comparative assessment carried out in the finite

Implementering av CALFEM för Python

The objective of this dissertation is to implement a large part of CALFEM functions to Python and to explore libraries and software in addition to NumPy needed to achieve a comparable environment for CALFEM. No actions will be taken to improve or change existing programming. Comparison of code and description of the main differences when writing in Python is done to simplify the transition for exis

Sidostabiltet för limträbågar

Limträbågar med lång spännvidd har ofta ett väldigt högt och slankt tvärsnitt. Detta medför risk för vippningsinstabilitet. En jämnsymmetrisk belastning av bågen ställer oftast inte till något problem, men då bågen belastas osymmetriskt uppkommer stora böjmoment som ökar risken för instabilitet markant. Raka balkar som belastas med punktlaster eller utbredda laster får ett tryck i balkens överkanGlulam arches with long span often have a very high and slender cross-section. This may cause lateral torsional buckling of the arch. A symmetrical loading doesn’t usually become a problem, but if the arch is loaded asymmetrical there will be large bending moments that increases the risk of instability significantly. Straight beams that are subjected to point loads or distributed loading will be s

Flexible Beams in Dymola

Mechanical systems can be modeled by connecting rigid bodies with loads and other components. Prescribed motions and initial values can be defined in a system. The behaviour of the rigid bodies can then be studied and their motions can be computed. If a body is elastic the motion of some defined points are not identical to a rigid body when loads are affected. To model a mechanical system the dyna

Vibration Analysis of Underground Tunnel at High-Tech Facility

Max-lab is a national laboratory operated jointly by the Swedish Research Council and Lund University. Nowadays, the Max project consist of three facilities (three storage rings): MAX I, MAX II, MAX III and one electron pre-accelerator called Max Injector. A new storage ring is needed due to improved nanotechnology. MAX IV is planned to be the next generation Swedish synchrotron radiation facilit

Träs tryckfasthet vinkelrätt fiberriktningen

At present there are no concrete guidelines how to calculate the pressure resistance capacity of the timber at the load perpendicular to grain. The test options ASTM, CEN and ICO gives three different results in testing of an equal body. With this knowledge the value for the characteristic compressive strength capacity of the pressure perpendicular to the grain will be reduced to 2.7 MPa. The reduc

Design of Equipment for Characterization of Elastomers Using Impact Testing

Ett viktigt moment vid tillverkning av kartongmaterial till livsmedels-förpackningar är laminatorn. I laminatorn täcks råpappersmaterialet av smält polymer i det så kallade nypet. Nypet i sin tur består av en stor kylvals och en mindre gummiklädd nypvals. Genom att styra kraften som verkar på nypvalsen kan kontakttrycket i nypet regleras. Vinkelhastigheten med vilken nypvalsen roterar är stor och

Design of Foundations for Wind Turbines

The Swedish government has specified a goal for the Swedish wind power that in 2020 it will generate 30 TWh of energy per year. This should be compared with the present energy produced from wind power of 2.5 TWh / year. To meet these goals, several thousand new wind turbines have to be built. Today, we build the most land-based wind turbines on strong and stiff soils, but probably in the future

Arkitektur och konstruktion i vertikal stad

En teoretisk vertikal stad konstrueras i ett samarbete mellan en student från Arkitektprogrammet och en student från Väg och vattenprogrammet. Den vertikala stadens vision är att skona naturen från horisontellt växande städer genom att bygga uppe i luften och endast ha ett litet fotavtryck på marken som påverkar naturen minimalt. Den vertikala staden vill genom att bygga en kompakt stad där samhäl

Vibation Reduction by Shaping the Terrain Topography

MAX-lab is a synchrotron radiation laboratory run in cooperation between Lund University and the Swedish Research Council. It currently consists of three stor-age rings, however, construction has begun of the fourth. MAX IV will be located outside of the Lund University Faculty of Engineering campus, in the northeastern part of Lund. Induced by the development in material technology at the nanomet

Traffic Induced Vibrations at Road-Bridge - Experimental and Numerical Analysis

In the north-east part of Lund, Sweden, the MAX IV facility is (in the event of writing this thesis) under construction. MAX IV is a synchrotron radiation facility which has a high requirement regarding low vibrations. Within this thesis a nearby road-bridge for the highway E22 was studied using experimental and numerical methods. The aim was to determine the magnitude of the road-bridge influence

Structural Response With Regard to Explosions

When a structure is subjected to an explosion, it will have a response that differs from the one that arises from a static load. Engineers are used to design for static loads but the common knowledge of how to design for explosions is weak. There are guidelines for how to design for explosions with simplified methods but they are partly outdated and the explanation of how they are derived is vague

Användarnas egenuttryckta behov och talboksverksamhetens framtid : den svenska talboksverksamheten ur ett användar- och empowermentperspektiv

The aim of this master’s thesis is to examine how the Swedish model for production and distribution of talking books to the print disabled can be designed in the future, on the basis of the self-expressed needs of the users. Three questions were formulated in order to achieve this aim: 1. What needs do the users, according to themselves, have in relation to talking books to achieve equal means of

"Att komma igång med motoriken i själen igen" - En kvalitativ studie av Arbetsförmedlingens stöd och insatser till människor med missbruksproblematik

Author: Kajsa Nilsson Title: To get started with the motor in the soul again Supervisor: Dolf Tops The purpose of this study was to examine the opportunities and support the Employment Ser-vice can provide people with substance abuse problems. In my study I have used a qualitative approach in the form of four semi-structured interviews with social consultants. Social Con-sultants working in th

Att bli vuxen med en sällsynt diagnos - En kvalitativ studie om övergången från barn- till vuxenvård

Sällsynta diagnoser är en bred grupp diagnoser som, trots att de var för sig är mycket ovanliga, tillsammans drabbar ett stort antal personer. På senare tid har framsteg inom forskningen lett till att medellivslängden ökat för många av dessa diagnoser och allt fler patienter uppnår vuxen ålder. Detta har skapat en ny patientgrupp som vuxensjukvården har svårt att ta hand om. Många utredningar har Background: Rare diseases, a diverse group of conditions which each represent few patients, are a challenge for the Swedish health care system. Despite efforts by the European Union and Swedish institutions to address these patients’ needs, there is still a lack of scientific studies and political initiatives when it comes to adult patients living with these diagnoses. Many patient organizations h