- Email: [email protected]
Stability of slope embankments to withstand rainfall erosion on Dubai roads
52A 921400 Slope instability phenomena in Greece: a statistical analysis Koukis, G; Ziourkas, C lnt Assoc Engng Geol Bull N43, April 1991. P47-60 Landslide frequency in Greece is increasing. A statistical analysis of slide phenomena is presented, based on 800 case studies reported up to 1986. Frequency distributions and consequences on different geological formations, and influences of altitude, rainfall, slope angle and orientation, and weathering are examined. Interrelations between the various parameters are investigated. Engineering geological and landslide frequency and distribution zonation maps have been prepared.
921401 Geological properties of large-scale highspeed landslides and their mechanism models Xiaoning, W lnt Assoc Engng Geol Bull N43, April 1991. P93-99 The influences of stratigraphy and lithology, structural geology, slide spatial conditions, slide inducing parameters, and manner of movement of the sliding mass have been studied for high speed landslides. Three typical mechanisms are established: high position sliding (or sliding-collapse) landslide, energy releasing and friction decreasing landslide, and structural energy releasing landslide. Typical conditions for each and case studies of their occurrence are described.
921402 Approach to the physics and the modeling of submarine flowslides Norem, H; Locat, J; Schieldrop, B Marine Geotechnol V9, N2, April-June 1990, P93-1ll Submarine flowslides are considered to consist of dense flow close to the sea bed and a turbidity current above. The former component is analysed, considering a granular material for which viscoplastic behaviour predominates. A two dimensional finite difference code and constitutive laws developed to describe the flow of granular materials are used. Predictions agree reasonably well with observed behaviour. To improve results, the upper boundary conditions and flow in the macroviscous region must be incorporated.
921403 Effects of abandoned underground workings on open pit slope design Watters, R J; Rehwoldt, E; Coulthard, J Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P721-728. Publ Rotterdam: A A Balkema, 1990 Heap leaching of low grade deposits recovered by open pit mining over abandoned underground workings is used in the western USA. The influence of irregularly distributed voids on open pit slope stability is not easily analysed by conventional methods. Analyses using the programs STABL5 (2D limit equilibrium) and FLAC (explicit finite difference) have therefore been used to examine failure path sensitivity to underground workings and fault zones, deformation and stress state of the slopes, and overall safety factors. Results indicate the methods used are successful and that old workings do not have major implications to slope stability.
9214O4 Mixed-material slope design: a case history Kendorski, F S; Myers, D A; Grenot, C H Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P729-736. Publ Rotterdam." ,4 ,4 Balkema, 1990 Mining a deeply dipping quartzite (65-70 deg) underlain by highly weathered shale, which acts as a soil, is examined. The technique used was to tunnel into the lowest exposure, and remove the toe by blasting, splitting the quartzite along a single plane and leaving quartzite facing on the slope. Problems arise if blocks do not detach, leaving the weak underslope, or the facing is removed, exposing the weak shale. Rock and soil mechanics analyses are presented and economic comparisons made between reducing extraction ratio to maintain thicker facing or accepting ore dilution and the need to cut the slope back to ensure stability. 921405 Rainwater inflow influence on open pit rock slope activities Mandzic, E H Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P737-742. Publ Rotterdam: ,4 A Balkema, 1990 The Smreka open pit iron ore mine is over 400m deep. Over 100 million cubic m of rock is permanently in movement on the north slope. This has been monitored since tension cracks first occurred in 1976. Cumulative data on surface movements, rainwater inflow and groundwater movement, and activity on the slope are presented. Rainwater inflow is seen to be the most important influence on stability. Time delay between rainfall and slope movement has been established, and is used in planning of mining activity. 921406 Investigation of sea cliff stability Miyake, T T; Vakili, J; Steiner, E A; Ayas, M Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P849-856. Publ Rotterdam." A A Balkema, 1990 Stability of a 60m cliff on the southern flank of the Palos Verdes Peninsula, California, has been investigated. Bedrock is of the Monterey Formation, mainly gently dipping shales, siltstones, and sandstones, interlayered with intrusive basalts and tufts. Alteration of the tufts has led to man)' large landslides. Site characterisation and investigation are described. Two dimensional analysis based on the simplified Bishop method, and three dimensional analysis using the program CLARA, based on the extended Bishop method, have been carried out. The two analyses provide significantly different safety factors. 921407 Stability of slope embankments to withstand rainfall erosion on Dubai roads Chahrour, M A C; Sharafi, A A Proc 2nd International Conference on Foundations and Tunnels, London, 19-21 September 1989 112, P231-243. Publ Edinburgh: Engineering Technics Press, 1989 Road embankments in Dubai are generally constructed using cemented (Sabkha) or dune sands. The desert climate with occasional severe rainstorms results in severe erosion problems. Laboratory tests evaluated erosion resistance of Sabkha and dune sands, with and without cement and other additives, wet mix macadam, and wadi gravel road base material. Wet-dry durability was also examined. Based on these results, full scale tests of embankment sections treated by in situ cement stabilisation or by replacement of the top layers by
© 1992 Pergamon Press pie. Reproduction not permitted
53A imported Sabhka, wadi gravel, or wet mix were evaluated. Cost-benefit analysis indicates stabilisation of the existing embankment is preferred.
instrumentation scheme consists of convergence tapes, precision extensometers, and fixed, dual axis precision inclinometers.
921408 Practical approach for hazard evaluation of rock slopes in mountainous areas Barisone, G; Bottino, G Proe 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V3, P1509-1515. Publ Rotterdam: A A Balkema, 1990
921412 Sllp in the chalk cliffs at Brighton Corbett, B O Proc International Chalk Symposium, Brighton, 4-7 September 1989 P527-531. Publ London: Thomas Telford, 1990
A method developed to establish the risks associated with potentially unstable slopes and assist planning of monitoring and remedial measures is described. It is based on practical experiences of different areas in the Western Alps, and divides the slope into 5 hazard classes, based on Bieniawski's RMR and possible failure mechanisms of the rock mass, taking account of the relative orientation of slope and joint system and the residual friction angle of the slope. Hazard maps are illustrated. 921409 Cold lahar flows from Galunggung volcano (Indonesia) and their influence on life environments Brotodihardjo, A P P Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V3, P1517-1523. Publ Rotterdam: A A Balkema, 1990 The unexpected eruptions from the volcano in 1982-1983 expelled some 370 million cubic m of pyroclastic materials. During and since the eruptions cold lahar flows occurred during periods of heavy rainfall. The largest destroyed dams, embankments, and surface structures. Remedial and restorative measures are described. Coarse flow material can be used in construction whilst the transported fine material improves the fertility of the soil. Although no flows have occurred since 1988, the possibility of further movement remains. 921410 Lateral spreads and landslide hazards to the Northern Appenine. The example of Mt. Fumaiolo (Emilia Romagna) and Chiusi della Verna (Tuscany) Canuti, P; Casagli, N; Garzonio, C A; Vannocci, P Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V3, P1525-1535. Publ Rotterdam: A A Balkema. 1990 Deep and wide gravitational slope phenomena are found in regions of the Alps and Northern Appenines, particularly where hard, blocky rock masses overlie plastic shaly or clayey complexes. Lateral spread is seen, often accompanied by toppling failure and/or wedge detachment from the blocky rock mass. The geology of two such regions is described, including the joint systems. Landslide hazards are assessed. 921411 Kinematics of mountain-splitting processes based on continuous monitoring Glawe, U Proc International Conference on Mechanics of Jointed and Faulted Rock, Vienna, 18-20 April 1990 P141-148. Publ Rotterdam: A A Balkema, 1990 Continuous monitoring of cracks opening in a large limestone block on a sheared zone in Carinthia, Austria, is described. Strain-time curves have been developed which indicate underlying linear creep and phases of accelerated splitting, the latter being associated with water supply into the rock mass. The
A slip involving approximately 700 cubic metres of material occurred following heavy rainfall, after a path had been constructed from the top to bottom of a cliff in Brighton. The cliff consists of Upper Chalk overlain by a cover of Coombe deposits. Two major joint sets are visible and run from top to bottom of the cliff. The mechanism of the chalk slip and other possible failure mechanisms, effects of joint water, and other factors regarding stability are discussed. 921413 Stability of slopes in upper Cretaceous chalks in Israel Arkin, Y Proc International Chalk Symposium, Brighton, 4-7 September 1989 P533-540. Publ London: Thomas Telford, 1990 Seasonal and diurnal changes in natural water content have a direct effect on the stability of carbonate rock slopes in Israel. Excess water reduces the bulk density and thus strength, and the accompanying tensile stresses weaken it further, leading to failure. In view of these effects, a monitoring exercise was conducted at two sites with freshly excavated road cuts. Details of the investigations, geology of the area, and the stability analysis that followed are presented.
Earth retaining structures See also: 921264 921414 Pressure of clay backfill against retaining structures Clayton, C R I; Symons, I F; Hiedra-Cobo, J C Can Geotech J V28, N2, April 1991, P282-297 When cohesive backfills are used, lateral pressures are developed in three main stages: placement, compaction, and burial; horizontal stress reduction at constant moisture content; and swelling or consolidation at approximately constant vertical stress. The magnitude of pressure changes in each case has been examined in laboratory and pilot scale studies using clays of intermediate and high plasticity. Inadequacies of analyses developed for granular soils to describe observed behaviour are examined. Preliminary numerical studies indicate likely effects of plasticity and moisture content. 921415 Effect of footing shape on behaviour of cantilever retaining wall. Technical note Horvath, J S J Geoteeh Engng Div ASCE VII7, N6, June 1991, P973-978 Finite element modelling using the program SSTIPNM was used to examine the influence of the shape of the footing of a cantilever retaining wall on its performance. Four designs, sloped bottom and flat bottom with a shear key at the toe, below the stem, or at the heel, were considered. Translation and rigid body motion during and after construction were assessed. The sloped bottom alternative appears to perform best, but requires 13% more concrete than keyed alternatives.
© 1992 Pergamon Press plc. Reproduction not permitted
921401 Geological properties of large-scale highspeed landslides and their mechanism models Xiaoning, W lnt Assoc Engng Geol Bull N43, April 1991. P93-99 The influences of stratigraphy and lithology, structural geology, slide spatial conditions, slide inducing parameters, and manner of movement of the sliding mass have been studied for high speed landslides. Three typical mechanisms are established: high position sliding (or sliding-collapse) landslide, energy releasing and friction decreasing landslide, and structural energy releasing landslide. Typical conditions for each and case studies of their occurrence are described.
921402 Approach to the physics and the modeling of submarine flowslides Norem, H; Locat, J; Schieldrop, B Marine Geotechnol V9, N2, April-June 1990, P93-1ll Submarine flowslides are considered to consist of dense flow close to the sea bed and a turbidity current above. The former component is analysed, considering a granular material for which viscoplastic behaviour predominates. A two dimensional finite difference code and constitutive laws developed to describe the flow of granular materials are used. Predictions agree reasonably well with observed behaviour. To improve results, the upper boundary conditions and flow in the macroviscous region must be incorporated.
921403 Effects of abandoned underground workings on open pit slope design Watters, R J; Rehwoldt, E; Coulthard, J Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P721-728. Publ Rotterdam: A A Balkema, 1990 Heap leaching of low grade deposits recovered by open pit mining over abandoned underground workings is used in the western USA. The influence of irregularly distributed voids on open pit slope stability is not easily analysed by conventional methods. Analyses using the programs STABL5 (2D limit equilibrium) and FLAC (explicit finite difference) have therefore been used to examine failure path sensitivity to underground workings and fault zones, deformation and stress state of the slopes, and overall safety factors. Results indicate the methods used are successful and that old workings do not have major implications to slope stability.
9214O4 Mixed-material slope design: a case history Kendorski, F S; Myers, D A; Grenot, C H Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P729-736. Publ Rotterdam." ,4 ,4 Balkema, 1990 Mining a deeply dipping quartzite (65-70 deg) underlain by highly weathered shale, which acts as a soil, is examined. The technique used was to tunnel into the lowest exposure, and remove the toe by blasting, splitting the quartzite along a single plane and leaving quartzite facing on the slope. Problems arise if blocks do not detach, leaving the weak underslope, or the facing is removed, exposing the weak shale. Rock and soil mechanics analyses are presented and economic comparisons made between reducing extraction ratio to maintain thicker facing or accepting ore dilution and the need to cut the slope back to ensure stability. 921405 Rainwater inflow influence on open pit rock slope activities Mandzic, E H Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P737-742. Publ Rotterdam: ,4 A Balkema, 1990 The Smreka open pit iron ore mine is over 400m deep. Over 100 million cubic m of rock is permanently in movement on the north slope. This has been monitored since tension cracks first occurred in 1976. Cumulative data on surface movements, rainwater inflow and groundwater movement, and activity on the slope are presented. Rainwater inflow is seen to be the most important influence on stability. Time delay between rainfall and slope movement has been established, and is used in planning of mining activity. 921406 Investigation of sea cliff stability Miyake, T T; Vakili, J; Steiner, E A; Ayas, M Rock Mechanics Contributions and Challenges: Proc 31st US Symposium, Golden, 18-20 June 1990 P849-856. Publ Rotterdam." A A Balkema, 1990 Stability of a 60m cliff on the southern flank of the Palos Verdes Peninsula, California, has been investigated. Bedrock is of the Monterey Formation, mainly gently dipping shales, siltstones, and sandstones, interlayered with intrusive basalts and tufts. Alteration of the tufts has led to man)' large landslides. Site characterisation and investigation are described. Two dimensional analysis based on the simplified Bishop method, and three dimensional analysis using the program CLARA, based on the extended Bishop method, have been carried out. The two analyses provide significantly different safety factors. 921407 Stability of slope embankments to withstand rainfall erosion on Dubai roads Chahrour, M A C; Sharafi, A A Proc 2nd International Conference on Foundations and Tunnels, London, 19-21 September 1989 112, P231-243. Publ Edinburgh: Engineering Technics Press, 1989 Road embankments in Dubai are generally constructed using cemented (Sabkha) or dune sands. The desert climate with occasional severe rainstorms results in severe erosion problems. Laboratory tests evaluated erosion resistance of Sabkha and dune sands, with and without cement and other additives, wet mix macadam, and wadi gravel road base material. Wet-dry durability was also examined. Based on these results, full scale tests of embankment sections treated by in situ cement stabilisation or by replacement of the top layers by
© 1992 Pergamon Press pie. Reproduction not permitted
53A imported Sabhka, wadi gravel, or wet mix were evaluated. Cost-benefit analysis indicates stabilisation of the existing embankment is preferred.
instrumentation scheme consists of convergence tapes, precision extensometers, and fixed, dual axis precision inclinometers.
921408 Practical approach for hazard evaluation of rock slopes in mountainous areas Barisone, G; Bottino, G Proe 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V3, P1509-1515. Publ Rotterdam: A A Balkema, 1990
921412 Sllp in the chalk cliffs at Brighton Corbett, B O Proc International Chalk Symposium, Brighton, 4-7 September 1989 P527-531. Publ London: Thomas Telford, 1990
A method developed to establish the risks associated with potentially unstable slopes and assist planning of monitoring and remedial measures is described. It is based on practical experiences of different areas in the Western Alps, and divides the slope into 5 hazard classes, based on Bieniawski's RMR and possible failure mechanisms of the rock mass, taking account of the relative orientation of slope and joint system and the residual friction angle of the slope. Hazard maps are illustrated. 921409 Cold lahar flows from Galunggung volcano (Indonesia) and their influence on life environments Brotodihardjo, A P P Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V3, P1517-1523. Publ Rotterdam: A A Balkema, 1990 The unexpected eruptions from the volcano in 1982-1983 expelled some 370 million cubic m of pyroclastic materials. During and since the eruptions cold lahar flows occurred during periods of heavy rainfall. The largest destroyed dams, embankments, and surface structures. Remedial and restorative measures are described. Coarse flow material can be used in construction whilst the transported fine material improves the fertility of the soil. Although no flows have occurred since 1988, the possibility of further movement remains. 921410 Lateral spreads and landslide hazards to the Northern Appenine. The example of Mt. Fumaiolo (Emilia Romagna) and Chiusi della Verna (Tuscany) Canuti, P; Casagli, N; Garzonio, C A; Vannocci, P Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V3, P1525-1535. Publ Rotterdam: A A Balkema. 1990 Deep and wide gravitational slope phenomena are found in regions of the Alps and Northern Appenines, particularly where hard, blocky rock masses overlie plastic shaly or clayey complexes. Lateral spread is seen, often accompanied by toppling failure and/or wedge detachment from the blocky rock mass. The geology of two such regions is described, including the joint systems. Landslide hazards are assessed. 921411 Kinematics of mountain-splitting processes based on continuous monitoring Glawe, U Proc International Conference on Mechanics of Jointed and Faulted Rock, Vienna, 18-20 April 1990 P141-148. Publ Rotterdam: A A Balkema, 1990 Continuous monitoring of cracks opening in a large limestone block on a sheared zone in Carinthia, Austria, is described. Strain-time curves have been developed which indicate underlying linear creep and phases of accelerated splitting, the latter being associated with water supply into the rock mass. The
A slip involving approximately 700 cubic metres of material occurred following heavy rainfall, after a path had been constructed from the top to bottom of a cliff in Brighton. The cliff consists of Upper Chalk overlain by a cover of Coombe deposits. Two major joint sets are visible and run from top to bottom of the cliff. The mechanism of the chalk slip and other possible failure mechanisms, effects of joint water, and other factors regarding stability are discussed. 921413 Stability of slopes in upper Cretaceous chalks in Israel Arkin, Y Proc International Chalk Symposium, Brighton, 4-7 September 1989 P533-540. Publ London: Thomas Telford, 1990 Seasonal and diurnal changes in natural water content have a direct effect on the stability of carbonate rock slopes in Israel. Excess water reduces the bulk density and thus strength, and the accompanying tensile stresses weaken it further, leading to failure. In view of these effects, a monitoring exercise was conducted at two sites with freshly excavated road cuts. Details of the investigations, geology of the area, and the stability analysis that followed are presented.
Earth retaining structures See also: 921264 921414 Pressure of clay backfill against retaining structures Clayton, C R I; Symons, I F; Hiedra-Cobo, J C Can Geotech J V28, N2, April 1991, P282-297 When cohesive backfills are used, lateral pressures are developed in three main stages: placement, compaction, and burial; horizontal stress reduction at constant moisture content; and swelling or consolidation at approximately constant vertical stress. The magnitude of pressure changes in each case has been examined in laboratory and pilot scale studies using clays of intermediate and high plasticity. Inadequacies of analyses developed for granular soils to describe observed behaviour are examined. Preliminary numerical studies indicate likely effects of plasticity and moisture content. 921415 Effect of footing shape on behaviour of cantilever retaining wall. Technical note Horvath, J S J Geoteeh Engng Div ASCE VII7, N6, June 1991, P973-978 Finite element modelling using the program SSTIPNM was used to examine the influence of the shape of the footing of a cantilever retaining wall on its performance. Four designs, sloped bottom and flat bottom with a shear key at the toe, below the stem, or at the heel, were considered. Translation and rigid body motion during and after construction were assessed. The sloped bottom alternative appears to perform best, but requires 13% more concrete than keyed alternatives.
© 1992 Pergamon Press plc. Reproduction not permitted