Sökning: "concrete"

Visar resultat 36 - 40 av 1184 avhandlingar innehållade ordet concrete.

  1. 36. Material properties related to fire spalling of concrete

    Författare :Robert Jansson; Avdelningen för Byggnadsmaterial; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Concrete; thermal properties; fire spalling; polypropylene fibres;

    Sammanfattning : Despite almost 100 years of research, the fundamentals of fire spalling of concrete are not yet fully understood. Many different theories exist, each trying to describe the coupling between different phenomenon leading to fire spalling. Some of these phenomenon have been investigated and are presented in this thesis. LÄS MER

  3. 37. Toward Realistic Failure Evaluations for Concrete Buttress Dams

    Författare :Jonas Enzell; Anders Ansell; Erik Nordström; Andreas Sjölander; Richard Malm; Leif Lia; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; concrete dams; buttress dams; stability analysis; dam failure behavior; physical model tests; FEM; betongdammar; lamelldammar; stabilitetsanalys; dammbrott; fysiska modellförsök; FEM; Betongbyggnad; Concrete Structures;

    Sammanfattning : Concrete dams, complex structures supporting massive loads, have traditionally been assessed using simplified 2D analytical stability analyses based on the rigid body assumption. Previous studies have shown that 3D behavior, such as the interaction between the monoliths and the valley's geology, can greatly impact the load-bearing capacity of gravity dams but remains largely unexplored in buttress dams. LÄS MER

  4. 38. Reliability-based assessment procedures for existing concrete structures

    Författare :Joakim Jeppsson; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; concrete; reliability theory; service life; assessment; monitoring; hydraulic engineering; Civil engineering; offshore technology; soil mechanics; Väg- och vattenbyggnadsteknik;

    Sammanfattning : A feasibility study of reliability theory as a tool for the assessment of present safety and residual service life of damaged concrete structures has been performed in order to find a transparent methodology for the assessment procedure. It is concluded that the current guidelines are open to interpretation and that the variation in the results obtained regarding the structural safety is too great to be acceptable. LÄS MER

  5. 39. Plasticity and Damage Mechanics for Modeling Concrete Failure

    Författare :Peter Grassl; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlocal; concrete; localization; plasticity; damage;

    Sammanfattning : Concrete structures exhibit strongly non-linear and complex mechanical behavior. Hence, they are nowadays often analyzed by means of the finite element method, whereby a realistic description of the material behavior is decisive for the validity of the results. LÄS MER

  7. 40. Condition assessment of concrete dams in cold climate

    Författare :Rikard Hellgren; Anders Ansell; Richard Malm; Anders Wiberg; Fernando Salazar González; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dam safety; dams; data analysis; monitoring; statistical models; hydraulic structures; static ice loads; concrete dams; cold regions; Betongbyggnad; Concrete Structures;

    Sammanfattning : Dams in many countries are approaching their expected service life. Proper assessment of the aging dams structural health increase the knowledge of the current safety, and allow for better planning of renovation and rebuilding investments. LÄS MER