Sökning: "Fracturing"

Visar resultat 6 - 10 av 57 avhandlingar innehållade ordet Fracturing.

1. 6. Determination of virgin rock stresses by fracturing methods

   Författare :Christer Ljunggren; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mining and Rock Engineering; Gruv- och Berganläggningsteknik;

   Sammanfattning : .... LÄS MER

3. 7. Excavation damage from blasting with emulsion explosives : Quality control and macro fracturing in the remaining rock

   Författare :Henrik Ittner; Håkan Schunnesson; Daniel Johansson; Radoslava Ivanova; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gruv- och Berganläggningsteknik; Mining and Rock Engineering;

   Sammanfattning : Excavation damage is usually regulated in Swedish infrastructure tunnel contracts as it can influence the quality and lifecycle cost for tunneling projects. The topic is important for underground constructions with a long operation period such as tunnels for public transport, permanent access tunnels in mines or underground repositories for nuclear waste. LÄS MER

4. 8. Rock damage caused by underground excavation and meteorite impacts

   Författare :Ann Bäckström; Robert Zimmerman; John A Hudson; Flavio Lanaro; Pekka Särkkä; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Excavation Damage Zone EDZ ; Fracture analysis; Pre-existing fractures; Class II behaviour; 3D laser scanning; Impact fracturing; Geoengineering; Geoteknik;

   Sammanfattning : The intent of this thesis is to contribute to the understanding of the origin of fractures in rock. The man-made fracturing from engineering activities in crystalline rock as well as the fracturing induced by the natural process of meteorite impacts is studied by means of various characterization methods. LÄS MER

5. 9. Understanding Zircon Geochronology - Constraints from Imaging and Trace Elements

   Författare :Andrius Rimsa; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hydrothermal; Petrology; mineralogy; hydraulic fracturing; Sveconorwegian; incipient charnockite; EBSD; cathodoluminescence; REE; Zircon; U-Pb geochronology; geochemistry; Petrologi; mineralogi; geokemi; Kerala Khondalite Belt;

   Sammanfattning : Formation of incipient charnockite in Söndrum, SW Sweden and the Kerala Khondalite Belt (KKB), S. India is accompanied by zircon growth. The age of the dehydration event is constrained by dating newly formed zircon to 1397±4 Ma (2?, MSWD=1.7) in Söndrum and ca. LÄS MER

7. 10. On the hot crack formation during solidification of iron-base alloys

   Författare :Karin Hansson; KTH; []
   Nyckelord :hot cracking; hot tearing; cracking fracturing ; tearing; ductility; brittleness; embrittlement; fractures; ductile brittle transition; solidification; iron; copper; nickel; Invar; steels; free machining steels; stainless steels; penetration; crack;

   Sammanfattning : Hot cracking during solidification is a severe problem inmany casting processes, for example in continuous casting.Combinations of low strength and low ductility of the materialat high temperatures and applied tensile stress can cause hotcracking. LÄS MER