Underground excavation in jointed rocks

... scaling factor γsi Spacing limit scaling factor defined by discontinuity i γsj Spacing limit scaling factor defined by discontinuity j γsk Spacing limit scaling factor defined by discontinuity ... UNDERGROUND EXCAVATION IN JOINTED ROCKS JIAO XUGUANG (B.Eng.(Hons.),NUS) A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ENGINEERING DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERING NATION...

Ngày tải lên: 30/09/2015, 10:12

... The Earth After Us This page intentionally left blank The Earth After Us What Legacy Will Humans Leave in the Rocks? Jan Zalasiewicz with contributions from ... have been predicting the end of the Earth ever since humans lived in caves Just how does one make sense out of these varied viewpoints?—they all seem individually so plausible Just what is...

Ngày tải lên: 11/06/2014, 09:43

... trends and challenges of underground works in hard rock, in particular with the behaviour of brittle rock In mining, ever increasing international competitiveness has forced the industry to find innovative ... UNDERGROUND WORKS IN HARD ROCK TUNNELLING AND MINING P K Kaiser1 M.S Diederichs2, C D Martin3, J Sharp4, and W Steiner5 ABSTRACT The rock mass arou...

Ngày tải lên: 11/07/2014, 15:20

... tunnel linings in overconsolidated clay Proceedings 7th International Symposium of Institution of Mining and Metallurgy and British Tunnelling Society, Tunnelling 94, London, pp 469-481 Bộjui, H and ... tunnels in difficult ground conditions Campo et al (1997) reported on various grouting and jet grouting works being completed in fine water-bearing soils, during the construct...

Ngày tải lên: 11/07/2014, 15:20

... 338 Tunnelling in weak rocks In other words, the stiffness of elastic zone will decrease drastically with increasing size of the broken zone However, the post-failure stiffness (Kf ) of the ... Type of and depth rock mass Kalawar 280 m Chhibro 600 m γ RQD Jn Jr Ja Jw SRF = = = = = = = Estimated support pressure (kg/cm2 ) After Barton et al (1974)...

Ngày tải lên: 09/08/2014, 16:21

... biotite Graphite distribution varies considerably among the thin sections Fifty-one slides contain graphite as inclusions within plagioclase grains, but not within the matrix Graphite inclusions ... no graphite; only one slide is high in graphite concentration and four have medium graphite concentrations Additionally, rocks where graphite only appears as inclusions in plagi...

Ngày tải lên: 21/09/2015, 21:27

... PRODUCTION Percolation theory in research of oil-reservoir rocks Ass Prof Dr Nguyen Van Phon Hanoi University of Mining and Geology Abstract Following the articles about fractal geometry in the research ... research of oil-reservoir rocks [1, 2], in this article, the author will introduce the application of percolation theory in researching the permeabili...

Ngày tải lên: 17/03/2014, 12:20

... deformation and results of Ar‐Ar dating in this  area  in order  to  constrain  in detail  the spatial  metamorphic evolution  and interpretation  of geodynamic setting of the Indochina.   ... inside this zone, so this W‐E metamorphic shear zone  could  be  representative  for the main  tectonic  boundary  between Kon Tum metamorphic massif and non metamorphic Truong Son belt d...

Ngày tải lên: 22/03/2014, 12:20

Ngày tải lên: 07/07/2014, 12:20

... polarized light, 40x NNH-3 Actinolite in a greenstone Like most monoclinic amphiboles actinolite has birefringence in the lower 2nd order Twinning, possibly relic from the original augite, can be seen ... Cummingtonite in a hornblende - biotite - cummingtonite amphibolite Like most monoclinic amphiboles, birefringence is in the lower second order Cross polarized light, 100x Q-603C Cum...

Ngày tải lên: 29/09/2014, 17:15

... exploitation conditions in Mao Khe coal mine - The sphere of study: study in the characterization of horizontal drilling technology; rotary – percussion drilling technology in the geological conditions ... of study; - Experiment in real conditions; monitoring and collecting real data about rotary - percussion drilling technology in horizontal drilli...

Ngày tải lên: 11/01/2015, 15:47

... the mobilised mass properties of an embedded improved soil raft in an excavation and how the known elemental properties are translated into the mass properties taking into account various in uencing ... Embedded Improved Soil Raft: Mass Properties 2.3 17 Embedded Improved Soil Raft: Mass Properties This section presents a review of studie...

Ngày tải lên: 14/09/2015, 14:09

... understanding of the behaviour of an excavation stabilised with an embedded improved soil berm, in particular the mechanisms involved in restraining the retaining wall; 4) To carry out numerical analyses ... behaviour of embedded improved soil berm in an excavation in present study An embedded improved soil berm behaves like a horizontal pile and...

Ngày tải lên: 15/09/2015, 21:57

... explain major aspects of 3D corner effects in the excavations xviii Nomenclature NOMENCLATURE A cross sectional area of the retaining wall B the width of excavation D distance behind retaining wall ... This assumption is more appropriate for a long trench excavation, such as excavation for pipe laying and drainage works In a cofferdam excavation, such as basement exca...

Ngày tải lên: 16/09/2015, 17:12

... matrix of soil {Pp} Vector of pile- soil interaction forces acting on pile {Ps} Vector of pile- soil interaction forces acting on soil {yo} Vector of lateral soil movements at the pile nodes in the ... (2001) to study the responses of a single pile and pile groups due to excavation- induced soil movement in sand It was reported that the induced bending mom...

Ngày tải lên: 16/09/2015, 17:13