Sökning: "plane state stress"

Visar resultat 1 - 5 av 31 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 :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 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

  3. 2. Experimental characterization and numerical modeling of compression perpendicular to the grain in wood and cross-laminated timber

    Författare :Shaheda T. Akter; Thomas K. Bader; Erik Serrano; Jan Oscarsson; Reinhard Brandner; Linnéuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rolling shear; biaxial testing; stress combination; RT-plane; moisture influence; rolling shear creep; digital image correlation; strain field; CLT connection; rotational stiffness; rullskjuvning; biaxiell undersökning; spänningskombination; RT-plan; fuktpåverkan; krypning vid rullskjuving; digital bildkorrelation; töjningsfält; KLTanslutning; rotationsstyvhet; Byggteknik; Civil engineering;

    Sammanfattning : Compression perpendicular to the grain (CPG) of wood is a typical loading situation in timber structures. It has been an extensively studied research topic for decades, due to the highly ductile behavior of wood under such loading, the large variations in mechanical properties, and the relevance of these properties in structural design. LÄS MER

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

    Författare :Magnus Stridh; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; 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

  5. 4. Wafer-level heterogeneous integration of MEMS actuators

    Författare :Stefan Braun; Göran Stemme; Martin A. Schmidt; KTH; []
    Nyckelord :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

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

    Författare :Christer Ljunggren; Luleå tekniska universitet; []
    Nyckelord :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