Sökning: "Uppsprickning"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet Uppsprickning.

  1. 1. Restraint Effects in Concrete Bridges : A Study of Cracking due to Thermal Actions and Shrinkage in Portal Frame Bridges

    Författare :Erik Gottsäter; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tvång; Betong; Uppsprickning; Temperaturlast; Plattrambro; FE-analys; Restraint; Concrete; Cracking; Thermal action; Portal frame bridge; FE-analysis;

    Sammanfattning : Thermal actions and shrinkage cause volume changes in concrete structures. In structures which are restrained from movements, the restraint effects can cause cracking. However, when cracking occurs, the structure can deform to some extent, which reduces the restraint stresses and thus also the crack widths. LÄS MER

  3. 2. New constraints on paleoreconstructions through geochronology of mafic dyke swarms in North Atlantic Craton

    Författare :Mimmi Nilsson; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; baddeleyit; U-Pb; geokronologi; large igneous province; mantelplym; superkontinent; paleorekonstruktion; North Atlantic craton; baddeleyite; Large Igneous Province; Mantle plume; supercontinent; paleoreconstruction; U-Pb; geochronology; North Atlantic craton;

    Sammanfattning : Earth history is punctuated by a series of events of supercontinent amalgamation and break-up. Fragments of old continents display rifted margins and orogenic sutures that testify their involvement in supercontinent cycles. LÄS MER

  4. 3. Modelling of localized failure with emphasis on band paths

    Författare :Robert Tano; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : Avhandlingen behandlar hur uppsprickning i material kan modelleras med finita element inom vilka sprickan modelleras som ett språng i förskjutningsfältet. Denna metod har visat sig ge en bättre möjlighet att beräkna sprickvägar oavsett hur elementnätet är utformat än vad några vanliga kontinuummetoder klarar av. LÄS MER

  5. 4. Inventory of geomechanical phenomena related to train-induced vibrations from tunnels

    Författare :Andreas Eitzenberger; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Geoteknik; Soil Mechanics; Mining and Rock Engineering; Gruv- och berganläggningsteknik;

    Sammanfattning : Banverket is expecting that the number of railway tunnels in densely populated areas will increase over the next 20 years due to the lack of available space on the ground surface, but also since the railway is considered an environmentally friendly solution of transportation for the future. The need for good predictions of vibration and noise levels in dwellings along the planned tunnels is therefore evident. LÄS MER

  7. 5. Durability of sprayed concrete : steel fibre corrosion in cracks

    Författare :Erik Nordström; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : A combination of sprayed concrete technique and steel fibre technology gives obvious advantages when saving the work needed to place conventional reinforcement. In rock strengthening applications this is most accentuated. Sprayed concrete in general, made by skilled workmen, will generally be of high quality and good durability. LÄS MER