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Behaviour of a propped retaining wall: results of a numerical experiment
28A was introduced and has developed over the years. Sufficient knowledge and data has been collected to allow reasonable predictions of the time and extent of failures.
851248 Some difficulties associated with the limit equilibrium method of slices Ching, R K H; Fredlund, D G Can Geotech J V20, N4, Not" 1983, P661-672 Several analytical problems associated with the limit equilibrium method of slices are discussed. These occur primarily in the numerical procedure as a result of the interslice force assumptions and geometric conditions imposed on the stability computations. Suggestions to circumvent these problems are made.
851249 Back calculations of slope failures by the secant method. Technical note Nguyen, V U Geotechnique V34, N3, Sept 1984, P423-427 A recent development in slope analysis is reviewed. Back calculations of slope failure, interpretated as an optimization process is systematically and effectively carried out by the secant method. The method is suitable for back calculations involving a maximum of three unknown geomechanical parameters and requires a few iterations for convergence. A graphic representation of the range of possible solutions in obtainable for sensitivity analyses.
851250 Cement stabilisation of railings and the security of tips Llewellyn, L I D Mine Quarry V13, NS, May 1984, P28-33 In the South Wales coalfields, UK, mine washery tailings are being stabilised by mixing with a small percentage of Portland cement prior to their being disposed of to tip. A preferred method of tip construction has also been developed.
851251 Rapid tunneling solves Utah's landslide crisis Byce, J Tunnlg Technol Newsi N45, March 1984, 5P A massive landslide down the western slope of the Spanish Fork Canyon, Utah, USA, created an earthern dam. The dam created a lake in the canyon from the continuing runoff from melting snowpack. The slide also blocked vital rail and highway routes. Emergency measures to alleviate this problem involved: (I) construction of a temporary water diversion tunnel to prevent overflowing of the lake, and (2) rapid driving of new railroad tunnels around the landslide area.
851252 Stabilization of a high pit slope by means of huge cable anchors prepared in Czechoslovakia Zajic, J Proc International Symposium on Rock Bolting, Abisko, 28 August-2 September 1983 1>613-615. Publ Rotterdam: A. A. Balkema, 1984 Stabilization of several hundred metres high mountain slopes of crystalline rock above a very large open pit mine in a Tertiary brown-coal basin is at present under preparation in northwestern Bohemia. The principal stabilizing system will consist of 100 to 200MN anchors made of steel ropes fixed in long galleries. Auth.
851253 Surface coal mine spoil stability study, eastern coal province. Volume 1 Swanson, P G; Giese. C: Jones. J S US Bureau of Mines report OFR 52( 1)-84.25 Aug 19,~3. 168P The objective of this project was to quantitatively assess the slope stability problems associated with coal surface mining in the eastern coal province and to recommend spoil placement techniques that provide for slope stability. Data were collected for 11 minesites in Alabama, Kentucky, Ohio. Pennsylvania. Tennessee, and West Virginia. A site was selected in each of the six States on which a detailed investigation was conducted. The investigations included drilling through the slide into solid ground beneath, collecting samples at various depths for identification, and for laboratory tests. A topographic survey and field monitoring was conducted to determine field conditions at each slide. It was concluded that there are numerous factors related to the geologic and topographic conditions within the region that contribute substantially to the problems of spoil stability. The most significant factor appears to be the steep topography of the areas being mined. Auth.
Avail: NTIS, Springfield, Va 22161, USA (PB 84-178672) 851254 Surface coal mine spoil stability study, eastern coal province. Volume 2 Swanson, P G; Giese, C; Jones, J S US Bureau of Mines report OFR 52(2)-84.25 Aug 1983, 351P The objective of this project was to quantitatively assess the slope stability problems associated with coal surface mining in the eastern coal province and to recommend spoil placement techniques that provide for slope stability. Data were collected from 11 minesites in Alabama, Kentucky, Ohio, Pennsylvania, Tennessee, and West Virginia. Volume 2 contains the field data of each site collected during the study. A review of the site geology, a stratigraphic section, and a geologic structure map is provided for each site.
Avail: NTIS, Springfield, Va 22161, USA (PB 84-178680) 851255 Surface coal mine spoil stability study, eastern coal province. Manual of practice Swanson, P G; Giese, C; Jones, J S US Bureau of Mines report OFR 52(3)-84, 25 Aug 1983, 41P The manual applies the predictive matrices developed in a parent study for use in evaluating the stability of typical mine spoil slopes. The values of internal friction and pore pressure coefficient are derived for many varied slope conditions. The results can be used in conventional stability analysis equations to assist mine operators or regulatory personnel in evaluating spoil stability from very limited information.
Avail: NTIS, Springfield, Va 22161, USA (PB 84-178698) Earth retaining structures 851256 Behaviour of a propped retaining wail: results of a numerical experiment Potts, D M; Fourie, A B Geoteeimique I'34, N3, Sept 1984, P383-404 The behaviour of a single propped retaining wall has been modelled by finite element methods using an elasto-plastic constitutive law to represent the soil. The model was used to in-
29A vestigate the effects of method of construction (excavation or backfilling) and the coefficient of earth pressure at rest in situ. The results of the investigation indicate that for excavated walls in soils with a high initial coefficient of earth pressure value prop forces and wall bending moments greatly exceed those predicted by current design methods. For backfilled and excavated walls in soil with low initial coefficient of earth pressure at rest, displacements are much smaller and conventional design methods produce conservative values of prop forces and bending moments.
851257 Differential slice approach to the problem of retaining wall loading. Short communication Michalowski, R L lnt J Num Anal Meth Geomech VS, N5, Sept-Oct 1984, P493-502 A differential slice technique is applied in order to obtain the solution for the pressure distribution on rigid retaining walls. The technique is based on a statical analysis of a plane differential slice, for which only the global equilibrium is required. An analytical solution to the problem is found for a non-cohesive material and a linear slip surface. For more complicated cases the numerical solution is required. Auth.
851258 Sheet pile design earth pressure for strip load Steenfelt, J S; Hansen, B J Geotech Engng Div ASCE VllO, NGTT, July 1984, P976986 In order to demonstrate the effect from a strip load on the design of sheet pile wails, the earth pressure on a rigid vertical wall rotating about a point near the top of the wall is calculated for cohesionless soil using Brinch Hansen's earth pressure theory. A complete analytical solution corresponding to the calculation of the earth pressure by means of a circular failure arc is given together with charts demonstrating the results for the (plane) internal angle of friction = 30 deg. It is shown that the surcharge/unit weight ratio and the position of the strip load have significant influence on the design loads and that simple rules-of-the-thumb should be carefully examined in order to ensure safe design procedures. Auth.
851259 Temporary retaining structures session of the XV Italian Congress on Geotechnics (In Italian) Scarpelli, G Riv ltal Geotec VI7, N4, Oct-Dec 1983, P232-238 The main contributions to the session on temporary retaining structures are summarized.
Influence o f dynamic loads due to explosions or earthquakes 851260 Earthquake-soil structure interaction, spring and dasbpot models, and real soil behaviour Pender, M J Bull N Z Nat Soc Earthq Engng VI6, N4, Dec 1983, P320330 The earthquake response of a simple soil-structure interaction system is discussed. The nonlinear hysteretic properties of the soil on which the structure is founded are modelled. It is found that the nonlinear soil behaviour leads to a reduction in the response of the structure. Auth. RMMS.
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F
851261 Effects of reservoir bottom absorption on earthquake response of concrete gravity dams Fenves, G; Chopra, A K Earthq Engng Struct Dynam VI1, N6, Nor-Dec 1983, P809829 851262 Seismic behaviour of gravity dams founded on low shear strength soil Tucovic, I V Int Water Power Dam Constr V35, N1, Jan 1983, P28-31 An 'acceptable sliding condition' is proposed, for the maximum credible earthquake, where differential movement of the dam and its foundations is allowed that will not jeopardize the structural integrity.
851263 Seismic displacements in slopes by limit analysis Chang, C J; Chen, W F; Yao, J T P J Geotech Engng Div ASCE Vl10, NGT7, July 1984, P860874 An extended and modified version of the pseudo-static slope stability analysis is used to evaluate the critical state and the subsequent displacement response of slopes to earthquakes. The upper-bound pseudo-static limit analysis is applied for the determination of critical state of slopes, in this case, the yield acceleration and corresponding failure mechanism. Based on the calculated yield acceleration and the critical failure surface, Newmark's analytical procedure is then used to assess the soil displacements of slopes, which are subjected to a given earthquake load. The technique avoids the complexities of the stress strain analysis approach and the inaccuracies of conventional pseudo-static analysis.
851264 Evaluation of kinematic interaction of soil-foundation systems by a stochastic model Hoshiya, M; Ishii, K Soil Dynam Earthq Engng V2, N3, July 1983, P128-134 The kinematic interaction of an embedded rectangular foundation by the random vibration theory is evaluated. The formulation is based on the fact that statistical correlation of ground motions at different points decreases as the distance between the points increases. Three different types of structure are analysed with the model: a large scale inground tank; a foundation whose material is cement-mixed soil-improved ground; and a multi storey building.
851265 Deformation of centrifuge models of clay embankments due to 'bumpy road' earthquakes Kutter, B L Soil Dynam EarthqEngng V2, N4, Oct 1983, P199-205 A new apparatus, called the 'Bumpy Road' has been developed to impose earthquake-like vibrations on centrifuge models. The apparatus has been used in model tests on kaolin embankments in order to verify the validity of using sliding block calculations to predict permanent displacements. The results indicate softening of the soil during an earthquake should be taken into account in the analysis, and a simple degradation model can be used to do this. In one model test, strain softening and pore pressures induced by the earthquake apparently induced collapse of the model a few seconds after the earthquake.
851248 Some difficulties associated with the limit equilibrium method of slices Ching, R K H; Fredlund, D G Can Geotech J V20, N4, Not" 1983, P661-672 Several analytical problems associated with the limit equilibrium method of slices are discussed. These occur primarily in the numerical procedure as a result of the interslice force assumptions and geometric conditions imposed on the stability computations. Suggestions to circumvent these problems are made.
851249 Back calculations of slope failures by the secant method. Technical note Nguyen, V U Geotechnique V34, N3, Sept 1984, P423-427 A recent development in slope analysis is reviewed. Back calculations of slope failure, interpretated as an optimization process is systematically and effectively carried out by the secant method. The method is suitable for back calculations involving a maximum of three unknown geomechanical parameters and requires a few iterations for convergence. A graphic representation of the range of possible solutions in obtainable for sensitivity analyses.
851250 Cement stabilisation of railings and the security of tips Llewellyn, L I D Mine Quarry V13, NS, May 1984, P28-33 In the South Wales coalfields, UK, mine washery tailings are being stabilised by mixing with a small percentage of Portland cement prior to their being disposed of to tip. A preferred method of tip construction has also been developed.
851251 Rapid tunneling solves Utah's landslide crisis Byce, J Tunnlg Technol Newsi N45, March 1984, 5P A massive landslide down the western slope of the Spanish Fork Canyon, Utah, USA, created an earthern dam. The dam created a lake in the canyon from the continuing runoff from melting snowpack. The slide also blocked vital rail and highway routes. Emergency measures to alleviate this problem involved: (I) construction of a temporary water diversion tunnel to prevent overflowing of the lake, and (2) rapid driving of new railroad tunnels around the landslide area.
851252 Stabilization of a high pit slope by means of huge cable anchors prepared in Czechoslovakia Zajic, J Proc International Symposium on Rock Bolting, Abisko, 28 August-2 September 1983 1>613-615. Publ Rotterdam: A. A. Balkema, 1984 Stabilization of several hundred metres high mountain slopes of crystalline rock above a very large open pit mine in a Tertiary brown-coal basin is at present under preparation in northwestern Bohemia. The principal stabilizing system will consist of 100 to 200MN anchors made of steel ropes fixed in long galleries. Auth.
851253 Surface coal mine spoil stability study, eastern coal province. Volume 1 Swanson, P G; Giese. C: Jones. J S US Bureau of Mines report OFR 52( 1)-84.25 Aug 19,~3. 168P The objective of this project was to quantitatively assess the slope stability problems associated with coal surface mining in the eastern coal province and to recommend spoil placement techniques that provide for slope stability. Data were collected for 11 minesites in Alabama, Kentucky, Ohio. Pennsylvania. Tennessee, and West Virginia. A site was selected in each of the six States on which a detailed investigation was conducted. The investigations included drilling through the slide into solid ground beneath, collecting samples at various depths for identification, and for laboratory tests. A topographic survey and field monitoring was conducted to determine field conditions at each slide. It was concluded that there are numerous factors related to the geologic and topographic conditions within the region that contribute substantially to the problems of spoil stability. The most significant factor appears to be the steep topography of the areas being mined. Auth.
Avail: NTIS, Springfield, Va 22161, USA (PB 84-178672) 851254 Surface coal mine spoil stability study, eastern coal province. Volume 2 Swanson, P G; Giese, C; Jones, J S US Bureau of Mines report OFR 52(2)-84.25 Aug 1983, 351P The objective of this project was to quantitatively assess the slope stability problems associated with coal surface mining in the eastern coal province and to recommend spoil placement techniques that provide for slope stability. Data were collected from 11 minesites in Alabama, Kentucky, Ohio, Pennsylvania, Tennessee, and West Virginia. Volume 2 contains the field data of each site collected during the study. A review of the site geology, a stratigraphic section, and a geologic structure map is provided for each site.
Avail: NTIS, Springfield, Va 22161, USA (PB 84-178680) 851255 Surface coal mine spoil stability study, eastern coal province. Manual of practice Swanson, P G; Giese, C; Jones, J S US Bureau of Mines report OFR 52(3)-84, 25 Aug 1983, 41P The manual applies the predictive matrices developed in a parent study for use in evaluating the stability of typical mine spoil slopes. The values of internal friction and pore pressure coefficient are derived for many varied slope conditions. The results can be used in conventional stability analysis equations to assist mine operators or regulatory personnel in evaluating spoil stability from very limited information.
Avail: NTIS, Springfield, Va 22161, USA (PB 84-178698) Earth retaining structures 851256 Behaviour of a propped retaining wail: results of a numerical experiment Potts, D M; Fourie, A B Geoteeimique I'34, N3, Sept 1984, P383-404 The behaviour of a single propped retaining wall has been modelled by finite element methods using an elasto-plastic constitutive law to represent the soil. The model was used to in-
29A vestigate the effects of method of construction (excavation or backfilling) and the coefficient of earth pressure at rest in situ. The results of the investigation indicate that for excavated walls in soils with a high initial coefficient of earth pressure value prop forces and wall bending moments greatly exceed those predicted by current design methods. For backfilled and excavated walls in soil with low initial coefficient of earth pressure at rest, displacements are much smaller and conventional design methods produce conservative values of prop forces and bending moments.
851257 Differential slice approach to the problem of retaining wall loading. Short communication Michalowski, R L lnt J Num Anal Meth Geomech VS, N5, Sept-Oct 1984, P493-502 A differential slice technique is applied in order to obtain the solution for the pressure distribution on rigid retaining walls. The technique is based on a statical analysis of a plane differential slice, for which only the global equilibrium is required. An analytical solution to the problem is found for a non-cohesive material and a linear slip surface. For more complicated cases the numerical solution is required. Auth.
851258 Sheet pile design earth pressure for strip load Steenfelt, J S; Hansen, B J Geotech Engng Div ASCE VllO, NGTT, July 1984, P976986 In order to demonstrate the effect from a strip load on the design of sheet pile wails, the earth pressure on a rigid vertical wall rotating about a point near the top of the wall is calculated for cohesionless soil using Brinch Hansen's earth pressure theory. A complete analytical solution corresponding to the calculation of the earth pressure by means of a circular failure arc is given together with charts demonstrating the results for the (plane) internal angle of friction = 30 deg. It is shown that the surcharge/unit weight ratio and the position of the strip load have significant influence on the design loads and that simple rules-of-the-thumb should be carefully examined in order to ensure safe design procedures. Auth.
851259 Temporary retaining structures session of the XV Italian Congress on Geotechnics (In Italian) Scarpelli, G Riv ltal Geotec VI7, N4, Oct-Dec 1983, P232-238 The main contributions to the session on temporary retaining structures are summarized.
Influence o f dynamic loads due to explosions or earthquakes 851260 Earthquake-soil structure interaction, spring and dasbpot models, and real soil behaviour Pender, M J Bull N Z Nat Soc Earthq Engng VI6, N4, Dec 1983, P320330 The earthquake response of a simple soil-structure interaction system is discussed. The nonlinear hysteretic properties of the soil on which the structure is founded are modelled. It is found that the nonlinear soil behaviour leads to a reduction in the response of the structure. Auth. RMMS.
22 I
F
851261 Effects of reservoir bottom absorption on earthquake response of concrete gravity dams Fenves, G; Chopra, A K Earthq Engng Struct Dynam VI1, N6, Nor-Dec 1983, P809829 851262 Seismic behaviour of gravity dams founded on low shear strength soil Tucovic, I V Int Water Power Dam Constr V35, N1, Jan 1983, P28-31 An 'acceptable sliding condition' is proposed, for the maximum credible earthquake, where differential movement of the dam and its foundations is allowed that will not jeopardize the structural integrity.
851263 Seismic displacements in slopes by limit analysis Chang, C J; Chen, W F; Yao, J T P J Geotech Engng Div ASCE Vl10, NGT7, July 1984, P860874 An extended and modified version of the pseudo-static slope stability analysis is used to evaluate the critical state and the subsequent displacement response of slopes to earthquakes. The upper-bound pseudo-static limit analysis is applied for the determination of critical state of slopes, in this case, the yield acceleration and corresponding failure mechanism. Based on the calculated yield acceleration and the critical failure surface, Newmark's analytical procedure is then used to assess the soil displacements of slopes, which are subjected to a given earthquake load. The technique avoids the complexities of the stress strain analysis approach and the inaccuracies of conventional pseudo-static analysis.
851264 Evaluation of kinematic interaction of soil-foundation systems by a stochastic model Hoshiya, M; Ishii, K Soil Dynam Earthq Engng V2, N3, July 1983, P128-134 The kinematic interaction of an embedded rectangular foundation by the random vibration theory is evaluated. The formulation is based on the fact that statistical correlation of ground motions at different points decreases as the distance between the points increases. Three different types of structure are analysed with the model: a large scale inground tank; a foundation whose material is cement-mixed soil-improved ground; and a multi storey building.
851265 Deformation of centrifuge models of clay embankments due to 'bumpy road' earthquakes Kutter, B L Soil Dynam EarthqEngng V2, N4, Oct 1983, P199-205 A new apparatus, called the 'Bumpy Road' has been developed to impose earthquake-like vibrations on centrifuge models. The apparatus has been used in model tests on kaolin embankments in order to verify the validity of using sliding block calculations to predict permanent displacements. The results indicate softening of the soil during an earthquake should be taken into account in the analysis, and a simple degradation model can be used to do this. In one model test, strain softening and pore pressures induced by the earthquake apparently induced collapse of the model a few seconds after the earthquake.