Sökning: "Rock stress"

Visar resultat 21 - 25 av 106 avhandlingar innehållade orden Rock stress.

1. 21. Evaluation of rock mass strength criteria

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

   Sammanfattning : Knowledge of the rock mass behaviour in general, the failure process and the strength in particular, is important for the design of all kinds of underground excavations. One of the most common ways of estimating the rock mass strength is by using a failure criterion. LÄS MER

3. 22. Pure shear fracture of brittle rock : a theoretical and laboratory study

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

   Sammanfattning : This doctoral thesis deals with determination of Mode II fracture toughness, KIIc, for rock. Three types of specimens, antisymmetric four-point bending, direct shearing and compression-shear specimens, are experimentally and numerically investigated. LÄS MER

4. 23. Post-failure behaviour of brittle rock

   Författare :Hossein M. Hakami; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mining and Rock Engineering; Gruv- och Berganläggningsteknik;

   Sammanfattning : The study of the post-failure behaviour of brittle rocks in the laboratory needs stiff and servo-controlled testing machines. Yet, the problem is not completely solved unless a suitable feedback signal is created for the servo-loop of the testing machine. LÄS MER

5. 24. Water powered percussive rock drilling : process analysis, modelling and numerical simulation

   Författare :Göran Tuomas; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vattenteknik; Water Resources Engineering;

   Sammanfattning : This thesis is devoted to problems, processes and systems related to the recently developed water powered percussive rock drilling method. The technology, which uses ordinary water to drive down-the-hole hammers, has been used to produce more than 6 million meters of blast holes within the mining industry. LÄS MER

7. 25. The Underground as a Storage Facility. Modelling of Nuclear Waste Repositories and Aquifer Thermal Energy Stores

   Författare :Thomas Probert; Matematisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; exponential decay; modelling; fractured rock; classical mechanics; quantum mechanics; Mathematical and general theoretical physics; relativity; statistical physics; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; relativitet; kvantmekanik; gravitation; statistisk fysik; termodynamik; Environmental technology; pollution control; kontroll av utsläpp; Miljöteknik; conformal flow; heat as a tracer; KBS-3; stress field; temperature field; analytical solution; salt buoyancy; groundwater flow; nuclear waste repository; aquifer thermal energy storage; Fysicumarkivet A:1998:Probert;

   Sammanfattning : The underground is a vast region, which is, too a large extent, unused by man. It has a large potential as a storage facility due to its vastness and availability. This thesis, which consists of eleven papers and reports, deals with nuclear waste repositories in solid rock and with aquifer thermal energy storage systems. LÄS MER