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Evaluating calculated risk in geotechnical engineering
IOIA 843190 Water flow into undersea mine workings Garritty, P lnt J Min Engng VI, N3, Oct 1983, p237-251 Production at a number of mines operating off the North East coast of the UK has been seriously affected by the percolation of significant quantities of water onto working coal faces. A detailed study of factors affecting the incidence and distribution of water inflows has been undertaken, using operational, geological and hydrological data. Analysis indicates that major inflows are a consequence of dynamic strata deformations, which induce discontinuities within the overburden capable of transmitting water from overlying aquiferous formations into workings. Operations tend to encounter excessive water inflows when: (1) cover to the Permian aquifer is less than 100m or major Coal Measure aquifers exist within about 45m of workings; (2) tensile face strains induced at the base of the Permian exceed 6ram/m; (3) sandstone strata forms less than one third of the overburden, implying a lack of competence in the seam roof; (4) major strata 'weights' or 'breaks' occur; and (5) faults or other major discontinuities are present in the roof strata. Auth.
843191 Method for shaft sinking using advanced release of hydrostatic pressure of quicksand layers at large depths (In Polish) Sztelak, J Zesz Nank Politech Siask, Gorn Nl12, 1982, P49-56 A method of shaft sinking under conditions of intensive water influx is described, particularly suitable where there are quicksand strata at depth. A shaft is sunk by conventional methods to a point where the shaft bottom is 20m from the sand layer. The bottom is then reinforced with a concrete layer and water draining boreholes are drilled through the bottom at a 70 deg angle. The draining boreholes create a drawdown cone around the shaft and reduce water influx to the shaft. When water inflow decreases to below 0.5cu m/min, shaft sinking is renewed.
843192 Post-construction seepage toward tunnels in variable head aquifers Bello-Maidonado, A A Proc 5th Congress of the International Society for Rock Mechanics, Melbourne, 10-15 April 1983 V1, PBI I I-BI I7. Publ Rotterdam: A. A. Balkema, 1983 A model is proposed for the prediction of values and variations of total inflow to a tunnel driven through unlimited, free and recharged aquifers with constant hydraulic head over the tunnel. The model is extended to cover groundwater flow into tunnels driven in aquifers with variable head for the construction and post completion period.
Influence o f d y n a m i c loads due to e x p l o s i o n s or earthquakes 843193 Resistance of a mechanical support without special protection against dynamic loading (In Czech) Budirsky, S Uldi I1"31, N4, April 1983, P142-146 Discusses the mechanism of the dynamic action of the solid rock mass on a support and develops a mathematical simulation of the behaviour of a support without special protection under the effect of sudden loading.
Surface Structures See also: 843333. 843383
843194 Calcutta Metro: contract section 1611 Roy, T lnst Civ Engr Proc V74, Nov 1983, P871-883 A special construction method was required for this 60m length of cut and cover excavation, due to: (1) restricted head room and (2) the proximity of piers and abutments which are on shallow spread foundations, on water-surcharged fine silty sand. Following the construction of temporary walling consisting of cast-in-situ liner piles and interlocking panels a reinforced temporary raft was installed. Finally the bottom slab (permanent raft) and the top slab were laid. Problems encountered during the work were the existence ofcavities requiring sand filling and grouting and inflows of liquid to semi-plastic soil.
843195 Evaluating calculated risk in geotechnical engineering Whitman, R V J Geotech Engng Div ASCE VIIO, NGT2, Feb 1984, P145188 Some of the applications of applied probability to geotechnical engineering are discussed: (1) separating systematic and random errors when evaluating uncertainty in the stability of slopes, (2) safety factors in connection with the analysis of liquefaction, (3) optimizing the design of an embankment in the face of uncertainty concerning stability, (4) risk evaluation for an industrial facility built over potentially liquefiable soils and (5) risk evaluation for earth dams. 59 refs.
843196 Design of pipelines in mudslide areas Bea, R G; Aurora, R P J Pet Technol V35, NI2, Nov 1983, P1985-1995 A design strategy is presented for routing and configuring pipelines in mudslide areas. This strategy is illustrated with a case study of a pipeline in the Mississippi River Delta. The case study focuses on the geotechnical aspects of pipeline settlement, flotation, and analysis of mudslide forces and stresses.
843197 Limit analysis and stability of excavations (In French) Pastor, J Proc lOth International Conference on Soil Mechanics and Foundation Engineering, Stockholm, 15-19 June 1981 V3, P505-508. Pub/Rotterdam: A. A. Balkema, 1981
843198 Urban refuse and used fires in civil engineering (In French) Cartier, G; Long, N T; Pouget, P; Bargillat, R; Cudennec, J P Proc lOth International Conference on Soil Mechanics and Foundation Engineering, Stockholm, 15-19 June 1981 V3, P603-606. Publ Rotterdam: A. A. Balkema, 1981 Presents two examples to illustrate construction of embankments on urban and industrial waste materials. The use of old tyres as a means of soil reinforcement is also demonstrated.
D a m s and e m b a n k m e n t s See also: 843015, 843040, 843305
843191 Method for shaft sinking using advanced release of hydrostatic pressure of quicksand layers at large depths (In Polish) Sztelak, J Zesz Nank Politech Siask, Gorn Nl12, 1982, P49-56 A method of shaft sinking under conditions of intensive water influx is described, particularly suitable where there are quicksand strata at depth. A shaft is sunk by conventional methods to a point where the shaft bottom is 20m from the sand layer. The bottom is then reinforced with a concrete layer and water draining boreholes are drilled through the bottom at a 70 deg angle. The draining boreholes create a drawdown cone around the shaft and reduce water influx to the shaft. When water inflow decreases to below 0.5cu m/min, shaft sinking is renewed.
843192 Post-construction seepage toward tunnels in variable head aquifers Bello-Maidonado, A A Proc 5th Congress of the International Society for Rock Mechanics, Melbourne, 10-15 April 1983 V1, PBI I I-BI I7. Publ Rotterdam: A. A. Balkema, 1983 A model is proposed for the prediction of values and variations of total inflow to a tunnel driven through unlimited, free and recharged aquifers with constant hydraulic head over the tunnel. The model is extended to cover groundwater flow into tunnels driven in aquifers with variable head for the construction and post completion period.
Influence o f d y n a m i c loads due to e x p l o s i o n s or earthquakes 843193 Resistance of a mechanical support without special protection against dynamic loading (In Czech) Budirsky, S Uldi I1"31, N4, April 1983, P142-146 Discusses the mechanism of the dynamic action of the solid rock mass on a support and develops a mathematical simulation of the behaviour of a support without special protection under the effect of sudden loading.
Surface Structures See also: 843333. 843383
843194 Calcutta Metro: contract section 1611 Roy, T lnst Civ Engr Proc V74, Nov 1983, P871-883 A special construction method was required for this 60m length of cut and cover excavation, due to: (1) restricted head room and (2) the proximity of piers and abutments which are on shallow spread foundations, on water-surcharged fine silty sand. Following the construction of temporary walling consisting of cast-in-situ liner piles and interlocking panels a reinforced temporary raft was installed. Finally the bottom slab (permanent raft) and the top slab were laid. Problems encountered during the work were the existence ofcavities requiring sand filling and grouting and inflows of liquid to semi-plastic soil.
843195 Evaluating calculated risk in geotechnical engineering Whitman, R V J Geotech Engng Div ASCE VIIO, NGT2, Feb 1984, P145188 Some of the applications of applied probability to geotechnical engineering are discussed: (1) separating systematic and random errors when evaluating uncertainty in the stability of slopes, (2) safety factors in connection with the analysis of liquefaction, (3) optimizing the design of an embankment in the face of uncertainty concerning stability, (4) risk evaluation for an industrial facility built over potentially liquefiable soils and (5) risk evaluation for earth dams. 59 refs.
843196 Design of pipelines in mudslide areas Bea, R G; Aurora, R P J Pet Technol V35, NI2, Nov 1983, P1985-1995 A design strategy is presented for routing and configuring pipelines in mudslide areas. This strategy is illustrated with a case study of a pipeline in the Mississippi River Delta. The case study focuses on the geotechnical aspects of pipeline settlement, flotation, and analysis of mudslide forces and stresses.
843197 Limit analysis and stability of excavations (In French) Pastor, J Proc lOth International Conference on Soil Mechanics and Foundation Engineering, Stockholm, 15-19 June 1981 V3, P505-508. Pub/Rotterdam: A. A. Balkema, 1981
843198 Urban refuse and used fires in civil engineering (In French) Cartier, G; Long, N T; Pouget, P; Bargillat, R; Cudennec, J P Proc lOth International Conference on Soil Mechanics and Foundation Engineering, Stockholm, 15-19 June 1981 V3, P603-606. Publ Rotterdam: A. A. Balkema, 1981 Presents two examples to illustrate construction of embankments on urban and industrial waste materials. The use of old tyres as a means of soil reinforcement is also demonstrated.
D a m s and e m b a n k m e n t s See also: 843015, 843040, 843305