Structural integrity of a reinforced concrete structure and a pipe outlet under hydrogen detonation conditions

    Research output: Book/ReportReport

    Abstract

    Structural integrity of a reinforced concrete wall and a pipe penetration under detonation conditions in a selected reactor building room of Olkiluoto BWR were studied. Hydrogen leakage from the pressurised containment to the surrounding reactor building is possible during a severe accident. Leaked hydrogen tends to accumulate in the reactor building rooms where the leak is located leading to a stable stratification and locally very high hydrogen concentration. If ignited, a possibility to flame acceleration and detonation cannot be ruled out. The structure may survive the peak detonation transient because the eigenperiod of the structure is considerably longer than the duration of the peak detonation. However, the relatively slowly decreasing static type pressure after a peak detonation damages the wall more severely. Elastic deformations in reinforcement are recoverable and cracks in these areas will close after the pressure decrease. But there will be remarkable compression crushing and the static type slowly decreasing over pressure clearly exceeds the loading capacity of the wall. Structural integrity of a pipe outlet was considered also under detonation conditions. The effect of drag forces was taken into account. Damping and strain rate dependence of yield strength were not taken into consideration. The boundary condition at the end of the pipe line model was varied in order to find out the effect of the stiffness of the pipeline outside the calculation model. The calculation model where the lower pipe end is free to move axially, is conservative from the pipe penetration integrity point of view. Even in this conservative study, the highest peak value for the maximum plastic deformation is 3.5%. This is well below the success criteria found in literature.
    Original languageEnglish
    Number of pages40
    Volume73
    Publication statusPublished - May 2002
    MoE publication typeD4 Published development or research report or study

    Fingerprint

    Structural integrity
    Detonation
    Concrete construction
    Reinforced concrete
    Pipe
    Hydrogen
    Crushing
    Elastic deformation
    Yield stress
    Drag
    Strain rate
    Plastic deformation
    Accidents
    Reinforcement
    Pipelines
    Damping
    Stiffness
    Boundary conditions
    Cracks

    Keywords

    • Non-linear reinforced concrete
    • pipe outlet
    • hydrogen detonation
    • finite element analysis

    Cite this

    @book{e9123f42e8324a6f8d1e314531565ed0,
    title = "Structural integrity of a reinforced concrete structure and a pipe outlet under hydrogen detonation conditions",
    abstract = "Structural integrity of a reinforced concrete wall and a pipe penetration under detonation conditions in a selected reactor building room of Olkiluoto BWR were studied. Hydrogen leakage from the pressurised containment to the surrounding reactor building is possible during a severe accident. Leaked hydrogen tends to accumulate in the reactor building rooms where the leak is located leading to a stable stratification and locally very high hydrogen concentration. If ignited, a possibility to flame acceleration and detonation cannot be ruled out. The structure may survive the peak detonation transient because the eigenperiod of the structure is considerably longer than the duration of the peak detonation. However, the relatively slowly decreasing static type pressure after a peak detonation damages the wall more severely. Elastic deformations in reinforcement are recoverable and cracks in these areas will close after the pressure decrease. But there will be remarkable compression crushing and the static type slowly decreasing over pressure clearly exceeds the loading capacity of the wall. Structural integrity of a pipe outlet was considered also under detonation conditions. The effect of drag forces was taken into account. Damping and strain rate dependence of yield strength were not taken into consideration. The boundary condition at the end of the pipe line model was varied in order to find out the effect of the stiffness of the pipeline outside the calculation model. The calculation model where the lower pipe end is free to move axially, is conservative from the pipe penetration integrity point of view. Even in this conservative study, the highest peak value for the maximum plastic deformation is 3.5{\%}. This is well below the success criteria found in literature.",
    keywords = "Non-linear reinforced concrete, pipe outlet, hydrogen detonation, finite element analysis",
    author = "Arja Saarenheimo and Ari Silde and Kim Calonius",
    note = "Project code: V1SU00138",
    year = "2002",
    month = "5",
    language = "English",
    isbn = "87-7893-129-0",
    volume = "73",

    }

    TY - BOOK

    T1 - Structural integrity of a reinforced concrete structure and a pipe outlet under hydrogen detonation conditions

    AU - Saarenheimo, Arja

    AU - Silde, Ari

    AU - Calonius, Kim

    N1 - Project code: V1SU00138

    PY - 2002/5

    Y1 - 2002/5

    N2 - Structural integrity of a reinforced concrete wall and a pipe penetration under detonation conditions in a selected reactor building room of Olkiluoto BWR were studied. Hydrogen leakage from the pressurised containment to the surrounding reactor building is possible during a severe accident. Leaked hydrogen tends to accumulate in the reactor building rooms where the leak is located leading to a stable stratification and locally very high hydrogen concentration. If ignited, a possibility to flame acceleration and detonation cannot be ruled out. The structure may survive the peak detonation transient because the eigenperiod of the structure is considerably longer than the duration of the peak detonation. However, the relatively slowly decreasing static type pressure after a peak detonation damages the wall more severely. Elastic deformations in reinforcement are recoverable and cracks in these areas will close after the pressure decrease. But there will be remarkable compression crushing and the static type slowly decreasing over pressure clearly exceeds the loading capacity of the wall. Structural integrity of a pipe outlet was considered also under detonation conditions. The effect of drag forces was taken into account. Damping and strain rate dependence of yield strength were not taken into consideration. The boundary condition at the end of the pipe line model was varied in order to find out the effect of the stiffness of the pipeline outside the calculation model. The calculation model where the lower pipe end is free to move axially, is conservative from the pipe penetration integrity point of view. Even in this conservative study, the highest peak value for the maximum plastic deformation is 3.5%. This is well below the success criteria found in literature.

    AB - Structural integrity of a reinforced concrete wall and a pipe penetration under detonation conditions in a selected reactor building room of Olkiluoto BWR were studied. Hydrogen leakage from the pressurised containment to the surrounding reactor building is possible during a severe accident. Leaked hydrogen tends to accumulate in the reactor building rooms where the leak is located leading to a stable stratification and locally very high hydrogen concentration. If ignited, a possibility to flame acceleration and detonation cannot be ruled out. The structure may survive the peak detonation transient because the eigenperiod of the structure is considerably longer than the duration of the peak detonation. However, the relatively slowly decreasing static type pressure after a peak detonation damages the wall more severely. Elastic deformations in reinforcement are recoverable and cracks in these areas will close after the pressure decrease. But there will be remarkable compression crushing and the static type slowly decreasing over pressure clearly exceeds the loading capacity of the wall. Structural integrity of a pipe outlet was considered also under detonation conditions. The effect of drag forces was taken into account. Damping and strain rate dependence of yield strength were not taken into consideration. The boundary condition at the end of the pipe line model was varied in order to find out the effect of the stiffness of the pipeline outside the calculation model. The calculation model where the lower pipe end is free to move axially, is conservative from the pipe penetration integrity point of view. Even in this conservative study, the highest peak value for the maximum plastic deformation is 3.5%. This is well below the success criteria found in literature.

    KW - Non-linear reinforced concrete

    KW - pipe outlet

    KW - hydrogen detonation

    KW - finite element analysis

    M3 - Report

    SN - 87-7893-129-0

    VL - 73

    BT - Structural integrity of a reinforced concrete structure and a pipe outlet under hydrogen detonation conditions

    ER -