Sökning: "prestressed"

Visar resultat 1 - 5 av 30 avhandlingar innehållade ordet prestressed.

  1. 1. Steel fibrous cement based composites: material and mechanical properties : behavior in the anchorage zones of prestressed bridges

    Författare :Lutfi Ay; KTH; []
    Nyckelord :process improvement of bridges; prestressed concrete; high performance concrete;

    Sammanfattning : This PhD thesis is divided into two parts. Part one dealswith the development of the material and the mechanicalproperties of Steel Fibrous Cement Based Composites (SFCBC) forimproving bridge design and construction. It familiarizes thehydration mechanisms of the high performance concrete with thehelp of Powers´ and Jensen´s models. LÄS MER

  3. 2. Analysis and Implementation of Preconditioners for Prestressed Elasticity Problems : Advances and Enhancements

    Författare :Ali Dorostkar; Maya Neytcheva; Thomas Huckle; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; FEM; Saddle point matrix; Preconditioning; Schur complement; Generalized Locally Toeplitz; Prestressed elasticity; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : In this work, prestressed elasticity problem as a model of the so-called glacial isostatic adjustment (GIA) process is studied. The model problem is described by a set of partial differential equations (PDE) and discretized with a mixed finite element (FE) formulation. LÄS MER

  4. 3. Shear and Torsion Interaction in Prestressed Hollow Core Slabs

    Författare :Helén Broo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shear-torsion capacity; hollow core unit; shear and torsion interaction; non-linear finite element analyses; hollow core slab; precast prestressed concrete; hollow core floor;

    Sammanfattning : There are many applications in which hollow core units are subjected to combined torsion and shear, for example in floors supported on three edges and in floors with openings. The traditional calculation method for combined shear and torsion in hollow-core units adds stresses from various sources without taking into account deformations and compatibility within the unit or restraint at the boundaries. LÄS MER

  5. 4. Assessment of Long-Term Losses in Prestressed Concrete Structures - Application for Nuclear Reactor Containments

    Författare :Peter Lundqvist; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; KstrConcrete; Nuclear reactor containments; prestressed concrete; prestress losses; bonded tendons; creep; shrinkage; relaxation; prediction models; resonance frequency; acoustoelasticity.;

    Sammanfattning : Most nuclear reactors, both in Sweden and worldwide, are enclosed by a prestressed concrete containment. The main purpose of the containment is to prevent any radioactive discharge to the environment in the event of a major internal accident. LÄS MER

  7. 5. Using prestressed steel fiber reinforced high performance concrete in the industrilization of bridge structures

    Författare :Lutfi Ay; KTH; []
    Nyckelord :Prestressed concrete; Casting steel fiber reinforced concrete; Bridges Casting steel fiber reinforced concrete; Bridges;

    Sammanfattning : .... LÄS MER