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2D modelling of resistivity and magnetotelluric data from the Belvedere Spinello salt mine, Italy
U N D E R G R O U N D EXCAVA~ONS:SUB~DENCE concrete segments, because the level of the groundwater, which can not be lowered, the unstable ground and the extraordinary road traffic conditions exclude the possibility of an open cut construction. Shaft and tunnels are to be built into strata of silt and clay. An Earth-Pressure-BalancedShield has been chosen for the construction of the tunnels. The starting and end length of the tunnels were scaled and stabilized by jet grouting. This made it possible to break out the tunnel openings in the diagram walls and to install the startrings with seals. The very limited space in the shaft made assembly, starting operation and the first 50 m of the tunnel drive extremely difficult and required a precise pre-planning of all the operations. The tunnel drive ends blind after 370 m, where the machine has to be dismantled under the protection of ground injection and with the loss of the first shield cylinder. Tunnel excavation of the second tunnel starts with a new shield cylinder, which will also be lost at the end of the drive. After the end of the tunnelling works an in-situ concrete invert with a drainage pipe and a cable channel will be installed. (from English summary)
Groundwater problems 957368 2D modelling of resistivity and magnetotenuric data from the Belvedere SpineHo salt mine, Italy V. Liiceto, G. Santarato & A. Zerilli, Geophysical Prosecting, 43(1), 1995, pp 77-89. In this mine an extensive mining program has caused the development of underground cavities f'dled with brine and the migration of which has been great environmental concern. This paper presents the results of a multidimensional interpretation of a two-phase resistivity and magnetotelluric (MT) survey, performed in an attempt to determine the complex conductivity structure of the mine area and to gain information on brine development and migration pathways. A conductivity model was developed, integrating available geological and driU-hole information. The interpretation of the MT data, collected five years after the acquisition of the resistivity data, shows a conductive feature of depth that is not resolved in the resistivity interpretation. This feature has been interpreted as a thick brine zone that has developed as a result of mining during the interval between the resistivity and the MT measurements. (from Authors) 957369 Improving ground characteristics D. J. Lees, Tunnels & Tunnelling, 27(3), 1995, pp 33-36. Discusses how drainage can be used in underground excavations and tunnelling to improve soil and rock conditions in water bearing ground. The influence of geology, drainage and dewatering methods for stabilisation, longterm drainage, groundwater seepage, the use of tunnels for drainage and recharge in areas where variations in groundwater occur, and drainage works for the rehabilitation of old tunnels are considered. (J.M.McLanghlin) 957370
Hydrogeologische Aspekte yon Tunndprojekten (Hydrogeological aspects of tunnel projects) G. Lombardi, Felsbau, 12(6), 1994, pp 452-457. The water conditions to be met in underground works may be even more severe than the rock conditions themselves. Water has a great influence both at construction time as well as during the life of the underground works. In this paper some aspects are dealt with which are related to the permeability of the rock mass such as: self-such induced concentration of water in the main faults, very high gradients and thus
353A
hydraulic generated forces near the opening, as well as possible settlements on the ground surface which may endanger existing structures like dams. (English summary) 957371 Hydrogenlogisehe Voruntersuchungen fur den SemmeringBasistunnel Mit besonderer Berucksichtigung yon Isoto-
penmessungen (Hydrogeological investigations for the Semmering railway tunnel, with separate consideration of isotope data) P. Reichl & H. Zojer, Felsbau, 12(6), 1994, pp 458-465. The 'Eisenbahnhochleistungsstrecken AG' is planning to construct a 22 km long railway tunnel through the Semmering mountain massif, which will connect the towns Murzzuschlag and Gloggnitz. The geological and hydrogeologieal set-up of the Semmering massif is extremely complicated. Many geological units, that make up the different nappes are exposed in this small area. The difference in the litbology and complicated structural setting of the rock units results in individual drainage systems in the massif. Regular hydrogeological monitoring has been going on since 1989. The evaluation of isotope data, combined with the results of other classical methods explains the drainage characteristics and storage capacities of the different rock units. (from English summary) 957372 Auswirkungen des Stollenvortriebs Kaponig auf die Berg-
wnsser-verhaltuisse (Effects of the Kaponig exploration tunnel on joint water conditions) P. Knoll, P. Ramspacher, G. Riedrnuller & A. Steidl, Felsbau, 12(6), 1994, pp 481-485. During the heading of the pilot tunnel Kaponig, which is driven through rock sequences of the Obere Schieferhulle a large amount of water inflow has been encountered over the first 1300 m, where overlying strata reach a thickness of several hundred meters. It is assumed that this high amount of water ingress in the tunnel is caused by deep-reaching loosening of the rock mass as a consequence of creeping mass movements. (English summary)
Surface subsidence, caving and rockbursts 957373
The environmental impact of mining in the province of Kntowice, Poland C. Rosik-Dulewska & L. Jarzebski, Coal International, 243(3), 1995, pp 109-110. Discusses the problems resulting from the extraction of hardcoal, zinc and lead ores from below the surface of Katowice. Extensive damage is caused to the environment and to surface installations by subsidence and earth movements, whilst tipping of mine spoil leads to a degradation of the landscape. Ways of combating these problems are discussed, such as back-filling using mine debris and the utilisation of wastematerial for industrial purposes. Reference is also made to the pollution caused by the diseharge of both saline and radioactive mine waters into rivers and surface water-courses.
(Authors) 957374
A study of the influence of weak viscoplastic strata in mine tunnels using finite element analysis R. Boughrarou & D. J. Reddish, International Journal of Rock Mechanics & Mining Sciences, 32(1), 1995, pp 71-75.
Groundwater problems 957368 2D modelling of resistivity and magnetotenuric data from the Belvedere SpineHo salt mine, Italy V. Liiceto, G. Santarato & A. Zerilli, Geophysical Prosecting, 43(1), 1995, pp 77-89. In this mine an extensive mining program has caused the development of underground cavities f'dled with brine and the migration of which has been great environmental concern. This paper presents the results of a multidimensional interpretation of a two-phase resistivity and magnetotelluric (MT) survey, performed in an attempt to determine the complex conductivity structure of the mine area and to gain information on brine development and migration pathways. A conductivity model was developed, integrating available geological and driU-hole information. The interpretation of the MT data, collected five years after the acquisition of the resistivity data, shows a conductive feature of depth that is not resolved in the resistivity interpretation. This feature has been interpreted as a thick brine zone that has developed as a result of mining during the interval between the resistivity and the MT measurements. (from Authors) 957369 Improving ground characteristics D. J. Lees, Tunnels & Tunnelling, 27(3), 1995, pp 33-36. Discusses how drainage can be used in underground excavations and tunnelling to improve soil and rock conditions in water bearing ground. The influence of geology, drainage and dewatering methods for stabilisation, longterm drainage, groundwater seepage, the use of tunnels for drainage and recharge in areas where variations in groundwater occur, and drainage works for the rehabilitation of old tunnels are considered. (J.M.McLanghlin) 957370
Hydrogeologische Aspekte yon Tunndprojekten (Hydrogeological aspects of tunnel projects) G. Lombardi, Felsbau, 12(6), 1994, pp 452-457. The water conditions to be met in underground works may be even more severe than the rock conditions themselves. Water has a great influence both at construction time as well as during the life of the underground works. In this paper some aspects are dealt with which are related to the permeability of the rock mass such as: self-such induced concentration of water in the main faults, very high gradients and thus
353A
hydraulic generated forces near the opening, as well as possible settlements on the ground surface which may endanger existing structures like dams. (English summary) 957371 Hydrogenlogisehe Voruntersuchungen fur den SemmeringBasistunnel Mit besonderer Berucksichtigung yon Isoto-
penmessungen (Hydrogeological investigations for the Semmering railway tunnel, with separate consideration of isotope data) P. Reichl & H. Zojer, Felsbau, 12(6), 1994, pp 458-465. The 'Eisenbahnhochleistungsstrecken AG' is planning to construct a 22 km long railway tunnel through the Semmering mountain massif, which will connect the towns Murzzuschlag and Gloggnitz. The geological and hydrogeologieal set-up of the Semmering massif is extremely complicated. Many geological units, that make up the different nappes are exposed in this small area. The difference in the litbology and complicated structural setting of the rock units results in individual drainage systems in the massif. Regular hydrogeological monitoring has been going on since 1989. The evaluation of isotope data, combined with the results of other classical methods explains the drainage characteristics and storage capacities of the different rock units. (from English summary) 957372 Auswirkungen des Stollenvortriebs Kaponig auf die Berg-
wnsser-verhaltuisse (Effects of the Kaponig exploration tunnel on joint water conditions) P. Knoll, P. Ramspacher, G. Riedrnuller & A. Steidl, Felsbau, 12(6), 1994, pp 481-485. During the heading of the pilot tunnel Kaponig, which is driven through rock sequences of the Obere Schieferhulle a large amount of water inflow has been encountered over the first 1300 m, where overlying strata reach a thickness of several hundred meters. It is assumed that this high amount of water ingress in the tunnel is caused by deep-reaching loosening of the rock mass as a consequence of creeping mass movements. (English summary)
Surface subsidence, caving and rockbursts 957373
The environmental impact of mining in the province of Kntowice, Poland C. Rosik-Dulewska & L. Jarzebski, Coal International, 243(3), 1995, pp 109-110. Discusses the problems resulting from the extraction of hardcoal, zinc and lead ores from below the surface of Katowice. Extensive damage is caused to the environment and to surface installations by subsidence and earth movements, whilst tipping of mine spoil leads to a degradation of the landscape. Ways of combating these problems are discussed, such as back-filling using mine debris and the utilisation of wastematerial for industrial purposes. Reference is also made to the pollution caused by the diseharge of both saline and radioactive mine waters into rivers and surface water-courses.
(Authors) 957374
A study of the influence of weak viscoplastic strata in mine tunnels using finite element analysis R. Boughrarou & D. J. Reddish, International Journal of Rock Mechanics & Mining Sciences, 32(1), 1995, pp 71-75.