Sökning: "plane state stress"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden plane state stress.

  1. 1. Shear cracks in concrete structures subjected to in-plane stresses

    Författare :Richard Malm; Håkan Sundquist; Kent Gylltoft; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Shear; plane state stress; crack width; FE analysis; design standards; serviceability state; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

    Sammanfattning : After only two years of service, extensive cracking was found in the webs of two light-rail commuter line bridges in Stockholm, the Gröndal and Alvik bridges. Due to this incident it was found necessary to study the means available for analysing shear cracking in concrete structures subjected to in-plane stresses. LÄS MER

  2. 2. Modeling Unsteady flow Effects in 3D Throughflow Calculations

    Författare :Magnus Stridh; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; throughflow; turbomachinery; mixing-plane; rotor-stator interaction; cascade; Deterministic stress terms; Linear harmonic; compressor; preconditioned GMRES; Unsteady; linear Navier-Stokes; turbine;

    Sammanfattning : The flow field in a transonic multistage compressor is compressible, three-dimensional and highly unsteady and can be predicted in principle by the exact time-accurate Navier-Stokes equations. The high Reynolds number encountered in multistage turbomachinery together with the wall-bounded nature of the flow environment however prevent the use of DNS to solve the exact N-S equations. LÄS MER

  3. 3. Wafer-level heterogeneous integration of MEMS actuators

    Författare :Stefan Braun; Göran Stemme; Martin A. Schmidt; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Microelectromechanical systems; MEMS; silicon; wafer-level; integration; heterogeneous integration; transfer integration; packaging; assembly; wafer bonding; adhesive bonding; eutectic bonding; release etching; electrochemical etching; microvalves; microactuator; Shape Memory Alloy; SMA; NITINOL; TiNi; NiTi; cold-state reset; bias spring; stress layers; crossbar switch; routing; switch; switch array; electrostatic actuator; S-shaped actuator; zipper actuator; addressing; transfer stamping; blue tape; Computer engineering; Datorteknik;

    Sammanfattning : This thesis presents methods for the wafer-level integration of shape memory alloy (SMA) and electrostatic actuators to functionalize MEMS devices. The integration methods are based on heterogeneous integration, which is the integration of different materials and technologies. LÄS MER

  4. 4. New developments in hydrofracturing stress measurement techniques and a comparison to the HTPF method

    Författare :Christer Ljunggren; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mining and Rock Engineering; Gruv- och Berganläggningsteknik;

    Sammanfattning : This thesis describes two hydraulic methods for rock stress measurements; hydraulic fracturing and hydraulic tests on pre-existing fractures (the HTPF method). It includes theories to evaluate stress field information for somewhat extraordinary stress and field situations, experimental investigations and field measurements. LÄS MER

  5. 5. On fracture of layered materials

    Författare :Jens Gunnars; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : This thesis is concerned with fracture in layered bimaterials. Fracture of coatings is considered to some extent. The behaviour of cracks growing normal to bimaterial interfaces is studied with the objective to clarify conditions for crack-tip shielding and amplification. LÄS MER