Seepage flow around tunnels in swelling rock

Seepage flow around tunnels in swelling rock

188A EXCAVATIONS:GROUNDWATER Seepage flow equations, usually formulated in a fixed cocordinate system are here reformulated within a frame of refere...

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188A

EXCAVATIONS:GROUNDWATER

Seepage flow equations, usually formulated in a fixed cocordinate system are here reformulated within a frame of reference that advances together with the tunnel heading. The governing equations contain the advance rate as an additional parameter, and are solved by the finite-element method. The quasi-steady state (i.e. the steady state in the moving frame of reference) can then be computed in a single step. Thanks to the economy of the proposed method, it has been possible to carry out comprehensive parametric studies, the results of which are presented in a dimensionless form. Appficability to poroclastic problems is also addressed. (from Author) 964347 Seepage flow around tunnels in swemng rock G. Anagnostou, International Journal for Numerical & Analytical Methods in Geomechanics, 19(10), 1995, pp 705724. The swelling phenomenon in tunneling is numerically modelled as a coupled hydraulic-mechanical process. This paper focuses on the significance of the constitutive seepage flow equations and the hydraulic boundary conditions. The observed absence of swelling deformations at the tunnel walls and the crown can be explained as a consequence of varying hydraulic boundary conditions. Results show that the nonlinearity of the unsaturated flow equations has a decisive qualitative influence on the predicted deformation field. (from Author) 964348 Alberta Lake ~ b l i ~ e d after draining to mine coal S. Sumer, L. Pitts, J. McCulioch & H. Quan, Mining Engineering, 47(11), 1995, pp 1015-1019. East Pit Lake is an artificially created lake that resulted from the remediation and reclamation of surface coal mining operations at TrausAlta Utilities' Whitewood Mine in the Wabamun area west of Edmonton, Alberta. The original excavation resulted from the creation of a mine end cut at the northern extent of the mining operation. Based on the simulations, the area in and around the lake was contoured to ensure that adequate littoral zones, average depths and slopes were maintained. When remediation was completed, the site was reclaimed with subsoiling and soil development, and seeded to native vegetation. The lake was subsequently assessed for its ability to support a recreational fishery. The results have been encouraging, with reclamation efforts nearing successful completion. (from Authors) 964349 Der Manefelder Knpferscbieferbergbau im gdnzugsgebiet des Snssen Sees - Geologische Voraussetzungen, Kulturlandschaftswandel and okologische Probleme (The Mansfeld copper shale mine in the catchment area of the Sussex See: geological conditions, variations in the cultivated landscape and ecological problems) G. Schmidt, Berichte zur Deutschen Landeskunde, 69(1), 1995, pp 93-110. A study was made of the effects of copper shale mining at Mansfeld in the catchment area of the Susser See. An attempt was made to ascertain the extent to which data obtained on individual sites in the area are representative of zones of the mine developed at particular times. In addition the study aimed to clarify whether the individual mining areas can be distinguished from each other by characteristic heavy metal contents in the soil and metal distribution patterns. It was shown that not only had each stage in the development of mining left visible traces in the form of different spoil heaps, but also that the different stages can be distinguished from each other from data on the content and distribution of heavy metals in the soil. (P.Cooke) 964350 Die grundwmmerverhaltalsse beim bauder 7. Maschiue des Dooankraftwerkes Ybbs-Persenbeug (The groundwater conditions) W. Einsiedler & G. Jung, Felsbau, 13(4), 1995, pp 231-235.

The construction of an additional unit in the Austrian Danube HPP required the excavation of an intake- and an outlet channel next to the impounded Danube river. Hydrogeologically two layers can be distinguished on the site. This report compares the groundwater conditions before excavation with situations prevailing during two important construction stages. The interaction of the different seating measures with the groundwater is discussed as well. (English summary) 964351 Influence of waters from sulfide mines and their dumps on surficial waters, soils, and plants H. Puchelt, Z. Berner, J. Castro & T. Rude, in: Water-rock interaction. Proc. symposium, Vladivostok, 1995, ed Y.K. Kharaka & O.V. Chudacv, (Balkema), 1995, pp 899-900. Sulfides from mines and their dumps are oxidized on contact with air and percolating waters. Only after oxidation can the elements contained in them be mobilized. The resultant ions migrate in waters and soils and can be tramferred to plants. Their uptake depends on the plant species, soil conditions and pH and can be measured by means of a transfer factor. Acceptable concentrations of elements in foodstuff are given in terms of the threshold values by WHO or national health agencies. Distributions of elements between different parts of a plant depend on their concentrations in the soil and on the mineralogical composition and physico-chemical parameters of the soil. (Authors) 964352 The diamond mining quarries of east Siberia as a factor affecting surflcial water quality V. N. Borisov, S. V. Alexeev & V. A. Pleshevenkova, in:

Water-rock interaction. Proc. symposium, Vladivostok, 1995, ed Y.K. Kharaka & O.V. Chudacv, (Balkema), 1995, pp 863-865. The diamond deposits in East Siberia have been developed in open-pits under extremely hard conditions. The sedimentary sequence is frozen to the 140-600 m depth, and below it is saturated in chloride brines with mineralization % 100-400 g/ 1. In the zone of mining works the brines flow into diamondrecovering quarries. Kimberlites, as well as host carbonate rocks contain easily-soluble minerals, e.g. halite and gypsum. Besides, the mining infrastructure encompasses some thousands of citizens. These factors affect the hydrochemical regime of the northern rivers, and this is exemplified by Udachnaya pipe. (Authors) 964353 Consequence of the Kizel coafleld acid mine water disposal into karst cavities N. G. Maximovich, V. N. Kataev & S. M. Blinov, in: Waterrock interaction. Proc. symposium, Vladivostok, 1995, ed Y.K. Kharaka & O.V. Chudaev, (Balkema), 1995, pp 885888. Discharge of acid coal mine water into carbonate karst cavities leads to: 1 - changes of surface and underground water composition, 2 - filling of karst cavities with ironbearing deposits, and 3 - changes in the hydrogeological and hydrological regimes of the region. This paper reviews the results of coal mine water discharge in the West Urals Kizel coal basin. (Authors) 964354 Water-mineral interaction in repositories of spent fuel from nuclear power stations T. Paces, in: Water-rock interaction. Proc. symposium, Vladivostok, 1995, ed Y.K. Kharaka & O.V. Chudaev, (Balkema), 1995, pp 889-890. There will be four Russian made power reactors operating in the Czech Republic. The spent fuel from these reactors likely will be stored in metal containers for emplacement in granitic caverns at 300-1000 m depth. Possible water-rock interactions in this setting and the environmental concerns are covered in this report. (Author)