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Compressed air tunneling through saturated porous media
U N D E R G R O U N D EXCAVATIONS:DYNAMIC LOADS has a great potential to predict quantitatively the higher permeable area. (Authors) 953287 Environmental meamn'es by means of groundwater control considering effects after construction of subway structures I. Koshiishi, A. Nakamura, T. Suzuki & Y. Takagi, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 165-172.
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reinforced concrete supports that were used as structural slabs were adopted to enhance the safety of excavation. 3) As a very deep construction was carried out, the RC diaphragm walls were used as the earth-retaining wall. To reduce the construction cost significantly, an up-to
Sendai City, the capital of the Tohoku District in Japan, is working on placing the Senseki Line underground, and the part that is to be placed under the streets is being constructed by the 'Cut and Cover Method.' For the construction at the gravel-bed section where the groundwater level is high, the authors have adopted S M W (Soil Mixing Wail), that is an impervious earth retainingwall, and planned to penetrate the embedment into bed rock. This wall cuts off most of the aquifer, and as a result,it is feared that plant roots will die due to a dam-up phenomena on the upper stream side and that wells and plants will dry up on the down stream side in the future. In order to deal with this problem, the authors have conceived to control the groundwater flow by means of removing parts of the retaining wall and to backfdl with permeable materials. (from Authors)
The use of compressed air for tunneling through saturated porous media is one of the common tunneling techniques specially when large size boulders are expected at the tunnel face. Upward flow of ground water, associated with compressed air tunneling, occurs and the stability of the surface and subsurface utilities is influenced. In this paper, factors controlling the properties of upward ground water flow are numerically investigated. Moreover, the effect of that upward flow and consequently the upward seepage force on the mobilization of ground movements is studied. (Author)
953288 Ground upheaval at an underground station due to rising groundwater level and subsequent restoration work T. Ishibashi, H. Ikeda & N. Kamata, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 127-134.
953291 Control of catchment area resulting from surface subsidence in plain, with high underground water (in Chinese) Ge Zhonghua & Shen Wen, Journal of China Coal Society, 19(2), 1994, pp 182-187.
An abnormal rise in the groundwater level due to a spell of heavy rain resulted in ground upheaval over a 100 m section at an underground station operated by the East Japan Railway Co. The underground station is located in a cutting protected by U-shaped retaining walls, which are approximately 12 m high and weight approximately 120 if/re. The railway line passes through tunnels on either side of the station. In the restoration work, the elevation of the station structure was reduced by approximately 50 cm by lowering the groundwater level. The space underneath the retaining walls was filled with low-strength non-segregating underwater mortar to ensure the stability of the lowered structure. As the station structure itself was undamaged, it was decided that it should be retained in use. In sections where sufficient lowering could not be achieved, the slabs were demolished and the ground was excavated for installation of new Ushaped slabs. As a measure against buoyancy, the structure was fixed down with ground anchors to provide it with an adequate resistance even if the water level were to rise as far as the ground surface level in future. (Authors)
In accordance with the basic characteristics of a catchment area resulting from subsidence in coal mines with high underground water, a comprehensive method for control of water-logging on the surface is proposed. An all round evaluation of different methods is made and rationalisation of the method confirmed. The water logged area is divided into four categories according to their features and degree of difficulty in control, and all kinds of control models for dealing with each category are also established. (English summary)
953289 Construction of a very deep subway station using cut-and cover method under high groundwater pressure J. Ono & K. Murata, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 187-194. This report concerns the construction of a subway station 40 m deep, 18 m wide and 251 m long. The station crosses existing structures such as a multi service tunnel, sewerage tunnel, the foundations of a huge surface structure called Air Dome, and the like, and also crosses other railways and makes connections with their stations. This station is situated in an aquiferous sand layer with high groundwater pressure. The characteristics of its design are as follows: 1) Since the construction site is in downtown Tokyo, a highly rigid RC diaphragm wall was adopted to minimize the influence of excavation upon neighboring buildings and elevated railway structures. 2) A deep well system was applied to lower the groundwater level and then to stabilize the bottom surface of the excavation. Additionally, large scale steep supports and
Influence of dynamic loads 953292 Dynamic analysis of tunnels S. Abdel-Salam, O. E. Shallan & A. Y. Akl, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 459-468. Dynamic analysis of tunnels is very complicated, where the equation of motion may be solved by many procedures, also the infinite domain of soil must be represented for the wave propagation, and the nonlinear properties of soil must be taken into consideration for a good representation. The aim of this research is to develop a new type of infinite element and use it as a numerical tool to study the seismic behavior of tunnels where a comprehensive program with many capabilities is introduced. (Authors) 953293 Behavior and damage of a Hned tunnel due to ground surface excavation T. Yasuoka & T. Kaneda, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 681-688. Bench blasting operations were carried out above a lined tunnel in a land reclamation site near Osaka in Japan. The 400 m long, 5.5 m wide tunnel was temporarily constructed for muck transportation by belt conveyors. The ground was excavated by 3 m-step bench blasting and the excavation
143A
reinforced concrete supports that were used as structural slabs were adopted to enhance the safety of excavation. 3) As a very deep construction was carried out, the RC diaphragm walls were used as the earth-retaining wall. To reduce the construction cost significantly, an up-to
Sendai City, the capital of the Tohoku District in Japan, is working on placing the Senseki Line underground, and the part that is to be placed under the streets is being constructed by the 'Cut and Cover Method.' For the construction at the gravel-bed section where the groundwater level is high, the authors have adopted S M W (Soil Mixing Wail), that is an impervious earth retainingwall, and planned to penetrate the embedment into bed rock. This wall cuts off most of the aquifer, and as a result,it is feared that plant roots will die due to a dam-up phenomena on the upper stream side and that wells and plants will dry up on the down stream side in the future. In order to deal with this problem, the authors have conceived to control the groundwater flow by means of removing parts of the retaining wall and to backfdl with permeable materials. (from Authors)
The use of compressed air for tunneling through saturated porous media is one of the common tunneling techniques specially when large size boulders are expected at the tunnel face. Upward flow of ground water, associated with compressed air tunneling, occurs and the stability of the surface and subsurface utilities is influenced. In this paper, factors controlling the properties of upward ground water flow are numerically investigated. Moreover, the effect of that upward flow and consequently the upward seepage force on the mobilization of ground movements is studied. (Author)
953288 Ground upheaval at an underground station due to rising groundwater level and subsequent restoration work T. Ishibashi, H. Ikeda & N. Kamata, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 127-134.
953291 Control of catchment area resulting from surface subsidence in plain, with high underground water (in Chinese) Ge Zhonghua & Shen Wen, Journal of China Coal Society, 19(2), 1994, pp 182-187.
An abnormal rise in the groundwater level due to a spell of heavy rain resulted in ground upheaval over a 100 m section at an underground station operated by the East Japan Railway Co. The underground station is located in a cutting protected by U-shaped retaining walls, which are approximately 12 m high and weight approximately 120 if/re. The railway line passes through tunnels on either side of the station. In the restoration work, the elevation of the station structure was reduced by approximately 50 cm by lowering the groundwater level. The space underneath the retaining walls was filled with low-strength non-segregating underwater mortar to ensure the stability of the lowered structure. As the station structure itself was undamaged, it was decided that it should be retained in use. In sections where sufficient lowering could not be achieved, the slabs were demolished and the ground was excavated for installation of new Ushaped slabs. As a measure against buoyancy, the structure was fixed down with ground anchors to provide it with an adequate resistance even if the water level were to rise as far as the ground surface level in future. (Authors)
In accordance with the basic characteristics of a catchment area resulting from subsidence in coal mines with high underground water, a comprehensive method for control of water-logging on the surface is proposed. An all round evaluation of different methods is made and rationalisation of the method confirmed. The water logged area is divided into four categories according to their features and degree of difficulty in control, and all kinds of control models for dealing with each category are also established. (English summary)
953289 Construction of a very deep subway station using cut-and cover method under high groundwater pressure J. Ono & K. Murata, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 187-194. This report concerns the construction of a subway station 40 m deep, 18 m wide and 251 m long. The station crosses existing structures such as a multi service tunnel, sewerage tunnel, the foundations of a huge surface structure called Air Dome, and the like, and also crosses other railways and makes connections with their stations. This station is situated in an aquiferous sand layer with high groundwater pressure. The characteristics of its design are as follows: 1) Since the construction site is in downtown Tokyo, a highly rigid RC diaphragm wall was adopted to minimize the influence of excavation upon neighboring buildings and elevated railway structures. 2) A deep well system was applied to lower the groundwater level and then to stabilize the bottom surface of the excavation. Additionally, large scale steep supports and
Influence of dynamic loads 953292 Dynamic analysis of tunnels S. Abdel-Salam, O. E. Shallan & A. Y. Akl, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 459-468. Dynamic analysis of tunnels is very complicated, where the equation of motion may be solved by many procedures, also the infinite domain of soil must be represented for the wave propagation, and the nonlinear properties of soil must be taken into consideration for a good representation. The aim of this research is to develop a new type of infinite element and use it as a numerical tool to study the seismic behavior of tunnels where a comprehensive program with many capabilities is introduced. (Authors) 953293 Behavior and damage of a Hned tunnel due to ground surface excavation T. Yasuoka & T. Kaneda, in: Tunnelling and ground conditions. Proc. congress, Cairo, 1994, ed M.E.A. Salam, (Balkema), 1994, pp 681-688. Bench blasting operations were carried out above a lined tunnel in a land reclamation site near Osaka in Japan. The 400 m long, 5.5 m wide tunnel was temporarily constructed for muck transportation by belt conveyors. The ground was excavated by 3 m-step bench blasting and the excavation