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Limit behavior of stone arch bridges
184A
EXCAVATIONS:TUNNELS
rock to simulate the ground shock in earthquake. Thus the dam-water-foundation system was excited by these blast shock waves travelling through the foundation rock. The theoretical calculated results basically agree with those measured in the field. The results show that the mathematical models of multiple excitation analysis of arch dams are reasonable. (English summary) 9643O7 Limit behavior of stone arch bridges P. Clemente, A. Oechiuzzi & A. Raithel, Journal of Structural Engineering- ASCE, 121(7), 1995, pp 1045-1050. In this paper, iterative methods to fmd the minimum thickness under dead loads and the collapse mechanism and load factor when acting also live loads are proposed. The results of a comprehensive numerical investigation are shown, which can be easily used in the safety check of stone arches. (from Authors) 9643O8 Seismic performance of mnitispsn simply supported slabon-girder steel highway bridges M. Dicleli & M. Bruneau, Engineering Structures, 17(1), 1995, pp 4-14. The seismic response of existing highway bridges, never designed to resist earthquakes, is studied. It is found that the response of two-span simply supported bridges is highly dependent on the stiffness of f'LXedbearings on the abutments, but this effect vanishes as the number of spans increases. The transverse direction seismic capacity of bridges having more than two spans is not a function of the number of spans. These bridges may be damaged by earthquakes having peak accelerations less than 0.20 g. However, bridges with identical end-to-end length but subdivided into a smaller number of spans are found to be more vulnerable to seismic excitations than those with larger number of spans. Increasing span length is also found to have a negative impact on the seismic capacity of these bridges. (from Authors) 964309 Inelsstic respouse of the Cypress Viaduct to the Loma Prleta eare~luake S. K. Kunnath & J. L. Gross, Engineering Structures, 17(7), 1995, pp 485-493. The inelastic damage evaluation of a typical double-deck bent of the Cypress Viadu~ which collapsed during the 1989 Loma Prieta earthquake is presented. The results of time-history analyses, which include a prediction of member damage, indicate that collapse was initiated by a shear failure of the pedestal regions. (from Authors)
EXCAVATIONS General 964310 A view of Paris' Meteor project: forging a new relationship between city and metro D. Bernard, Tunnelling & Underground Space Technology, 10(3), 1995, pp 343-352. The author traces the development of the Paris metro and examines the current situation with regard to its underground transportation network. The paper presents arguments for enhancing the underground environment as a specific space; extending the principles of surface layout to the underground development; and expanding opportunities for commercial activities and provision of services in underground space. (from Author)
Geological factors 964311 Die baageologisehen Verhaltnisse beim Bau der 7. Mnschine des Donaukraftwerkes Ybbs-Persenbeug (The engineering geelogleal eonditious) E. H. Weiss & G. Jung, Felsbau, 13(4), 1995, pp 187o193. For the construction of an additional unit at the Austrian Danube H I P numerous construction measures had to be applied because of limited space. The evaluation of the investigation program is described, especially the results of the water permeability tests in rocks and the degree of fissuring in the rock mass. The planniug of the rock support was to a large extend influenced by the engineering geological model of the rock conditions. During the excavation works the ground deformations have been monitored precisely to check the effectivity of the support measures. (English summary)
Stresses around openings 964312 Energy analysis of depresmrized reek fracture (in Chinese) Hun Anzeng, Kong Yuanbo, Li Shiping & Li Yushou, Journal - China Coal Society, 20(4), 1995, pp 389-392. Tests of marble samples were made under depressurized pressure by using stiff electro-hydrnnlic serve machine in order to simulate fracture of surrounding rocks in underground excavation. The results show that energy consumed changes significantly when rock samples are fracmx~ in depressurized and pressurized conditions. (English summary)
Excavation failure mechanisms 964313 Prediction of mining conditions at depth in Kristineberg mine, Sweden A. Nystrom, S. Sandstrom, N. Krauland & M. Board, Transactions - Institution of Mining & Metallurgy, Section A, 104(Sept-Dec), 1995, pp AI69-A177. In an attempt to address ground control problems at Swedish cut-and-fill mines a project entitled 'Mining at depth' was initiated in the late 1980s. The project was subdivided into two general areas: the prediction of mining conditions at depth and the adaptation of cut-and-fill ~nlniug to such conditions; and the assessment and improvement of support methods at present and future depths. These aspects of the investigation were addressed by means of simple, elastic, mine-scale numerical models for optimization of stope sequencing and more detailed, stope-scale models for simulation of the failure processes around a stope and the interaction of rock mass and support. The results of the predictive modelling were used as a basis for altering the interval between levels and stope sequencing at the mine. Several stages of ground support during the life of a stope were identified and have been implemented. Significant increases in productivity and redu~dons in mining costs have been achieved as a result of the modifications. (from Authors)
Tunnels 964314 Hazardous tunnelling, US style ANON, Tunnels & Tunnelling, 27(9), 1995, p 13. This short article discusses the problems encountered during tunnelling projects as presented at the 12th Rapid Excavation and Tunnelling Conference, June 1995, San Francisco. The projects included tunnelling through gasolene-contaminated ground below residential areas for the 1.5 mile twin-bore, northeast extension of the Baltimore Metro. Other contaminant problems in tunnelling projects are reviewed. (C.Palce)
EXCAVATIONS:TUNNELS
rock to simulate the ground shock in earthquake. Thus the dam-water-foundation system was excited by these blast shock waves travelling through the foundation rock. The theoretical calculated results basically agree with those measured in the field. The results show that the mathematical models of multiple excitation analysis of arch dams are reasonable. (English summary) 9643O7 Limit behavior of stone arch bridges P. Clemente, A. Oechiuzzi & A. Raithel, Journal of Structural Engineering- ASCE, 121(7), 1995, pp 1045-1050. In this paper, iterative methods to fmd the minimum thickness under dead loads and the collapse mechanism and load factor when acting also live loads are proposed. The results of a comprehensive numerical investigation are shown, which can be easily used in the safety check of stone arches. (from Authors) 9643O8 Seismic performance of mnitispsn simply supported slabon-girder steel highway bridges M. Dicleli & M. Bruneau, Engineering Structures, 17(1), 1995, pp 4-14. The seismic response of existing highway bridges, never designed to resist earthquakes, is studied. It is found that the response of two-span simply supported bridges is highly dependent on the stiffness of f'LXedbearings on the abutments, but this effect vanishes as the number of spans increases. The transverse direction seismic capacity of bridges having more than two spans is not a function of the number of spans. These bridges may be damaged by earthquakes having peak accelerations less than 0.20 g. However, bridges with identical end-to-end length but subdivided into a smaller number of spans are found to be more vulnerable to seismic excitations than those with larger number of spans. Increasing span length is also found to have a negative impact on the seismic capacity of these bridges. (from Authors) 964309 Inelsstic respouse of the Cypress Viaduct to the Loma Prleta eare~luake S. K. Kunnath & J. L. Gross, Engineering Structures, 17(7), 1995, pp 485-493. The inelastic damage evaluation of a typical double-deck bent of the Cypress Viadu~ which collapsed during the 1989 Loma Prieta earthquake is presented. The results of time-history analyses, which include a prediction of member damage, indicate that collapse was initiated by a shear failure of the pedestal regions. (from Authors)
EXCAVATIONS General 964310 A view of Paris' Meteor project: forging a new relationship between city and metro D. Bernard, Tunnelling & Underground Space Technology, 10(3), 1995, pp 343-352. The author traces the development of the Paris metro and examines the current situation with regard to its underground transportation network. The paper presents arguments for enhancing the underground environment as a specific space; extending the principles of surface layout to the underground development; and expanding opportunities for commercial activities and provision of services in underground space. (from Author)
Geological factors 964311 Die baageologisehen Verhaltnisse beim Bau der 7. Mnschine des Donaukraftwerkes Ybbs-Persenbeug (The engineering geelogleal eonditious) E. H. Weiss & G. Jung, Felsbau, 13(4), 1995, pp 187o193. For the construction of an additional unit at the Austrian Danube H I P numerous construction measures had to be applied because of limited space. The evaluation of the investigation program is described, especially the results of the water permeability tests in rocks and the degree of fissuring in the rock mass. The planniug of the rock support was to a large extend influenced by the engineering geological model of the rock conditions. During the excavation works the ground deformations have been monitored precisely to check the effectivity of the support measures. (English summary)
Stresses around openings 964312 Energy analysis of depresmrized reek fracture (in Chinese) Hun Anzeng, Kong Yuanbo, Li Shiping & Li Yushou, Journal - China Coal Society, 20(4), 1995, pp 389-392. Tests of marble samples were made under depressurized pressure by using stiff electro-hydrnnlic serve machine in order to simulate fracture of surrounding rocks in underground excavation. The results show that energy consumed changes significantly when rock samples are fracmx~ in depressurized and pressurized conditions. (English summary)
Excavation failure mechanisms 964313 Prediction of mining conditions at depth in Kristineberg mine, Sweden A. Nystrom, S. Sandstrom, N. Krauland & M. Board, Transactions - Institution of Mining & Metallurgy, Section A, 104(Sept-Dec), 1995, pp AI69-A177. In an attempt to address ground control problems at Swedish cut-and-fill mines a project entitled 'Mining at depth' was initiated in the late 1980s. The project was subdivided into two general areas: the prediction of mining conditions at depth and the adaptation of cut-and-fill ~nlniug to such conditions; and the assessment and improvement of support methods at present and future depths. These aspects of the investigation were addressed by means of simple, elastic, mine-scale numerical models for optimization of stope sequencing and more detailed, stope-scale models for simulation of the failure processes around a stope and the interaction of rock mass and support. The results of the predictive modelling were used as a basis for altering the interval between levels and stope sequencing at the mine. Several stages of ground support during the life of a stope were identified and have been implemented. Significant increases in productivity and redu~dons in mining costs have been achieved as a result of the modifications. (from Authors)
Tunnels 964314 Hazardous tunnelling, US style ANON, Tunnels & Tunnelling, 27(9), 1995, p 13. This short article discusses the problems encountered during tunnelling projects as presented at the 12th Rapid Excavation and Tunnelling Conference, June 1995, San Francisco. The projects included tunnelling through gasolene-contaminated ground below residential areas for the 1.5 mile twin-bore, northeast extension of the Baltimore Metro. Other contaminant problems in tunnelling projects are reviewed. (C.Palce)