Sökning: "Direct Shear"

Visar resultat 6 - 10 av 96 avhandlingar innehållade orden Direct Shear.

  1. 6. Pure shear fracture of brittle rock : a theoretical and laboratory study

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

    Sammanfattning : This doctoral thesis deals with determination of Mode II fracture toughness, KIIc, for rock. Three types of specimens, antisymmetric four-point bending, direct shearing and compression-shear specimens, are experimentally and numerically investigated. LÄS MER

  3. 7. Analysis and control of transitional shear flows using global modes

    Författare :Shervin Bagheri; Dan Henningson; Alessandro Bottaro; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; flow control; hydrodynamic stability; global modes; jet in crossflow; flat-plate boundary layer; laminar-turbulent transition; Arnoldi method; Koopman modes; balanced truncation; direct numerical simulations.; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : In this thesis direct numerical simulations are used to investigate two phenomenain shear flows: laminar-turbulent transition over a flat plate and periodicvortex shedding induced by a jet in cross flow. The emphasis is on understanding and controlling the flow dynamics using tools from dynamical systems and control theory. LÄS MER

  4. 8. Peak Shear Strength of Rock Joints – Towards a Methodology for Prediction Based on Field Data

    Författare :Francisco Ríos Bayona; Fredrik Johansson; Diego Mas Ivars; Stefan Larsson; José Muralha; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rock joints; peak shear strength; DEM; matedness; aperture; Bergssprickor; skjuvhållfasthet; DEM; sprickans passning; sprickvidd; Jord- och bergmekanik; Soil and Rock Mechanics;

    Sammanfattning : The rock joint shear strength at field scale is an important design parameter and remains a challenge for rock mechanics engineers. In Sweden, there exist a large number of concrete dams that are founded on rock masses which in many cases contain sub-horizontal rock joints. LÄS MER

  5. 9. Discrete element technique for modeling high-speed railway tracks

    Författare :Alireza Ahmadi; Stefan Larsson; Carl Wersäll; Liang Cui; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polygonal particles; Direct shear test; Particle scaling; Bal- lasted track; DEM; Polygonala partiklar; direkt skjuvförsök; partikelskalning; ballastspår; DEM; Soil and Rock Mechanics; Jord- och bergmekanik;

    Sammanfattning : The Discrete element method (DEM) is a methodology to investigatethe interactions among granular materials. It analyzes the behavior of par-ticulate environments by solving force-displacement equations that adhereto Newton’s second law of motion. LÄS MER

  7. 10. Experiments on oblique transition in wall bounded shear flows

    Författare :Per Elofsson; KTH; []
    Nyckelord :;

    Sammanfattning : This thesis considers laminar-turbulent transition in wall bounded shear flows, with a focus on transition emanating from a pair of oblique disturbance waves. The oblique waves interact nonlinearly and transfers disturbance energy into streamwise vortices, which generate streamwise streaks through a linear mechanism that operates also at conditions where stability theory predicts decay of all eigenmodes. LÄS MER