Sökning: "Hydraulic Structures"

Visar resultat 1 - 5 av 55 avhandlingar innehållade orden Hydraulic Structures.

  1. 1. Multiphase models for freeze-thaw actions and mass transport in concrete hydraulic structures

    Författare :Daniel Eriksson; Anders Ansell; Richard Malm; Erik Nordström; Stefan Jacobsen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Degradation; Hydraulic structures; Air-entrained concrete; Multiphase models; Multiphysics; Long-term moisture conditions; Freeze-thaw; Hysteresis; Absorption; Calcium leaching; Finite Element Method; Concrete Structures; Betongbyggnad;

    Sammanfattning : A crucial task for civil engineers is to make appropriate designs of new concrete structures and assessments of existing structures to ensure a long service life and sustainable use of the infrastructure. This doctoral thesis aims to increase the understanding of how advanced mathematical models can be used to describe phenomena and processes governing concrete degradation and thereby ultimately contribute to improving tools for design and assessments. LÄS MER

  3. 2. Moisture Conditions and Frost Resistance of Concrete in Hydraulic Structures

    Författare :Martin Rosenqvist; Avdelningen för Byggnadsmaterial; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydraulic Structures; Hydro Power; Concrete Dams; Concrete; Frost Resistance; Scaling; Spalling; Moisture Absorption; Macroscopic Ice Lens Growth;

    Sammanfattning : Owing to the winter conditions in Sweden, the effects of frost action may have a considerable impact on the deterioration of concrete. Both superficial and internal damage, which are suspected to have been caused by frost action, have been found in concrete in hydraulic structures. LÄS MER

  4. 3. Frost-induced deterioration of concrete in hydraulic structures : Interactions between water absorption, leaching and frost action

    Författare :MARTIN ROSENQVIST; Avdelningen för Byggnadsmaterial; []
    Nyckelord :Vattenbyggnader; Dammar; Betong; Cement; Vattenabsorption; Vattenmättnadsgrad; Nedbrytning; Frostbeständighet; Spjälkning; Makroskopisk islinsbildning; Urlakning; Synergi; Hydraulic structures; Dams; Concrete; Cement; Water absorption; Degree of saturation; Deterioration; Frost resistance; Spalling; Macroscopic ice lens growth; Leaching; Synergy;

    Sammanfattning : Frost deterioration of concrete can result in severe consequences to the safety, durability and functionality of a structure since it impairs the strength of the concrete. Frost damage may occur to structures that are in contact with water and subjected to frost action. LÄS MER

  5. 4. Numerical models for degradation of concrete in hydraulic structures due to long-term contact with water

    Författare :Daniel Eriksson; Anders Ansell; Richard Malm; Erik Nordström; Katja Fridh; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; degradation; deterioration mechanisms; hydraulic structures; air-entrained concrete; multiphase model; long-term moisture conditions; pore size distribution; freezing; partially saturated; finite element method; Civil and Architectural Engineering; Byggvetenskap;

    Sammanfattning : The durability of concrete is of major concern in all types of concrete structures where the combined effect of exposure conditions and the type and quality of the concrete material usually determines the rate of degradation. Furthermore, there are synergy effects between different deterioration mechanisms, which means that the combined rate of degradation is higher than the sum of the individual rates of each mechanism. LÄS MER

  7. 5. 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