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Full-Text Articles in Geotechnical Engineering
Settlement Experienced At A Recently Licensed Nuclear Station, J. T. Chen, L. W. Heller
Settlement Experienced At A Recently Licensed Nuclear Station, J. T. Chen, L. W. Heller
International Conference on Case Histories in Geotechnical Engineering
The settlement experienced at a recently licensed nuclear station demonstrated the need for coordination among geologists, geotechnical engineers and structural engineers to ensure that essential geological knowledge and experience is applied to the design and construction of the structures. The nuclear station had been under construction for a number of years when unexpected settlements were noticed which caused significant concrete cracking of the nuclear service water intake structure. The “seismic Category I” intake structure has an internal dimension of 12 feet wide by 15 feet high, a length of 167 feet with the thickness of walls and roof varied from …
Settlement Observations On Two Mat Foundations, E. Winter, P. Chung
Settlement Observations On Two Mat Foundations, E. Winter, P. Chung
International Conference on Case Histories in Geotechnical Engineering
The performance of two mat foundations is examined. The first case history includes a mat founded over generally granular terrace soils, underlain by a deep clay layer of medium compressibility. The second case history includes a mat over stiff preconsolidated clay. The mats are analyzed based on laboratory test and field pressuremeter data using the Winkler method. The particular approach taken in the analysis includes the determination of the modulus of subgrade reaction for the design using Vesic's method. Vesic (1968). This calculation was developed for pavements but is based on the theory of plates on elastic media which applies …
Settlement Of A Building Founded On Difficult Soil, Iqbal H. Khan, Fathi M. Layas
Settlement Of A Building Founded On Difficult Soil, Iqbal H. Khan, Fathi M. Layas
International Conference on Case Histories in Geotechnical Engineering
Many coastal areas in Benghazi have been reclaimed from lagoons. Quite often such areas are covered by debris, rubbish and other artificial fills over many years. The proximity of these deposits to the Mediterranean Sea coupled with the seasonal moisture variations has resulted in the formation of the so-called Sabkha soils having a high proportion of chemical content. Settlement records of a four storey building founded on sabkha soil are prescuted for seven years. The building underwent large settlement resulting in a tilt from the vertical. It is found that, for Sabkha soils, the measured settlement is larger than that …
Settlement Of A One Floor Building On Soft Clay Beside A Heavy Building, Mohamed A. El-Sohby, Ossama Mazen
Settlement Of A One Floor Building On Soft Clay Beside A Heavy Building, Mohamed A. El-Sohby, Ossama Mazen
International Conference on Case Histories in Geotechnical Engineering
A one floor building was founded on a deposit of normally consolidated soft clay. It was constructed to annex an existing three storey high building founded on piles. After construction, tilting and settlements of the Annexe were detected relative to the existing building. Recorded absolute and differential settlements, monitored over a period of five years, were considerably high. It is shown here that this could be caused by the combined effect of high compressibility, confinement of clay layers and variations in pressure distribution below foundations.
Settlement Performance Of A Mat Foundation On Unsaturated Loess, Alan J. Lutenegger, Bernard D. Remmes, Leo D. Handfelt
Settlement Performance Of A Mat Foundation On Unsaturated Loess, Alan J. Lutenegger, Bernard D. Remmes, Leo D. Handfelt
International Conference on Case Histories in Geotechnical Engineering
Previously reported settlements of structures founded on loess soils in the United States have been limited to cases of rapid deformation: the result of wetting and structural collapse. While the possibility of subsidence is usually a consideration in design, when the potential for wetting does not exist, economics generally govern the use of a shallow foundation system; in which case an accurate prediction of settlement is required. Since most loess deposits occur as unsaturated sediments, the use of one-dimensional consolidation theory is not applicable to the problem of settlement prediction. In 1977, a circular mat foundation was constructed on typical …
Stability Problems In A Deep Excavation In Clay, Gunnar Aas
Stability Problems In A Deep Excavation In Clay, Gunnar Aas
International Conference on Case Histories in Geotechnical Engineering
This paper describes the excavation procedure and some stability problems encountered in connection with a 10-m deep braced excavation in medium soft Oslo clay. Very large deformations in the first excavated sections made it clear that the factor of safety with respect to bottom heave failure was very close to unity, and hence, much lower than the value of 1.5 calculated from a conventional total stress analysis based on vane strength. Thus, the experiences from this excavation yield an excellent opportunity to test new and better methods of stability analysis which have been developed during the last 10 years. Furthermore, …
Repair Of A Reinforced Earth Wall, N. T. Long, J. Livet, M. Boutonnet, J. Marchal, G. Olivier, A. Nabonne, E. Plaut
Repair Of A Reinforced Earth Wall, N. T. Long, J. Livet, M. Boutonnet, J. Marchal, G. Olivier, A. Nabonne, E. Plaut
International Conference on Case Histories in Geotechnical Engineering
The facing of a Reinforced Earth retaining wall, built at an altitude of 1200 m, was damaged during the winter 1981. The repair was achieved quickly and under traffic. The instrumentation carried out on the repairs and the tests run on the backfill material have revealed the action of the frost and its increase in the fortuitous presence of water.
Thrust Evolution On The Shoring Of Two Large Excavations In Geneva, A. Fontana
Thrust Evolution On The Shoring Of Two Large Excavations In Geneva, A. Fontana
International Conference on Case Histories in Geotechnical Engineering
This study presents the results of thrust measures on the shoring of two large excavations, located in downtown Geneva, in fine saturated soils of low capacity and great thickness. Loads were measured by regular extensometer readings, completed in one excavation by three daily readings on VSL load cells. Although the obtained measurements seem puzzling at first sight, their analysis enable to draw some useful conclusions for the design of deep retaining structures.
Use Of Ground Anchors In Residual Soils, R. Kannan, Bengt B. Broms
Use Of Ground Anchors In Residual Soils, R. Kannan, Bengt B. Broms
International Conference on Case Histories in Geotechnical Engineering
In the past decade the use of ground anchors in deep basements has increased in most parts of the world, while their applications in Singapore have been very limited so far because of their interference with adjacent properties. Empirical design methods which are adequate in most cases are still commonly used. Analytical design methods and finite element analysis (FEM) which give better insight into the soil-anchor interaction are gaining popularity. Post grouting is often used for anchors in residual soils and has been found successful. Some case histories from Singapore are presented in this paper.
Load Measurements Of An Anchored Retaining Wall, P. Rocha Filho, N. M. Zeitoune
Load Measurements Of An Anchored Retaining Wall, P. Rocha Filho, N. M. Zeitoune
International Conference on Case Histories in Geotechnical Engineering
Thirty six anchors, corresponding approximately to five per cent of the total anchors of a retaining wall, were instrumented using electrical load cells, aiming to study the variation of the applied load with time associated with the sequencing of construction. It was observed that the average total loss was 25% of the average applied load, which consisted of three major component: rapid loss; long term loss and loss due to adjacent anchors loading.
Anchor Slab Retaining Wall Stands Overtopping Flood, Z. L. Wang, X. M. Wu, Z. S. Zhang
Anchor Slab Retaining Wall Stands Overtopping Flood, Z. L. Wang, X. M. Wu, Z. S. Zhang
International Conference on Case Histories in Geotechnical Engineering
An anchor slab retaining wall which stands seasonal overtopping floods was constructed in 1980 beside a river in the valley of Nanping, Fukien Province, China. Monitor measurements of its stresses and deformations were taken during the mean water level and flood seasons every year since its completion. The results of three years' observations and measurements proved that the wall is stable against floods and the earth pressure is slightly higher than the designed value.
Performance Of A 30 M Deep Instrumented Diaphragm Wall, M. M. Soares
Performance Of A 30 M Deep Instrumented Diaphragm Wall, M. M. Soares
International Conference on Case Histories in Geotechnical Engineering
This paper summarizes the performance of the second instrumented research section of the Rio de Janeiro underground. The first aim of this programme was to establish a simple procedure to design diaphragm walls in soft clay soils. The model of a beam on elastic supports was chosen due to its simplicity and usefulness in the prediction of the wall behaviour. The concrete wall was built using the slurry trench technique and was instrumented to measure the concrete strain, the load on the reinforcement bars, the horizontal displacement and the horizontal earth pressure. It was measured the loads in the two …
Permanent Tieback Retention System, T. C. Anderson, M. E. Lockwood, M. F. Nethero
Permanent Tieback Retention System, T. C. Anderson, M. E. Lockwood, M. F. Nethero
International Conference on Case Histories in Geotechnical Engineering
This paper describes the design, construction, and monitoring of a permanent tieback retention system which permitted a 55-foot-deep excavation for an 16-story addition to the existing Good Samaritan Hospital in Cincinnati, Ohio. Tieback anchor capacity is developed in moderate-to-low-strength shale bedrock with intermittent thin limestone layers. The retention system provides temporary and permanent support for adjacent 5- and 10-story buildings and unbalanced lateral earth pressures due to sloping site topography. A permanently tiedback wall also supports a 17-to-33-foot-deep cut adjacent to the a-story parking structure in lieu of a conventional retaining wall.
Discussions And Replies, Multiple Authors
Discussions And Replies, Multiple Authors
International Conference on Case Histories in Geotechnical Engineering
No abstract provided.
Embankments Built Over Swamps, Samuel Y. Ng, James C. Rudd
Embankments Built Over Swamps, Samuel Y. Ng, James C. Rudd
International Conference on Case Histories in Geotechnical Engineering
Time and environmental constraints necessitated the development of unique methods for building earthen embankments over very deep and soft swamp deposits. Three case histories are presented. Construction techniques included alternate strip embankments, use of flexible vertical and horizontal drains, use of wood chips and high strength geotextile and the conventional stage and preloading techniques. In all cases, field instrumentation including pore-pressure/settlement transducers was installed to monitor the fill placement. The monitoring results were fed into a computer to determine the safety factor against shear failure and amount of settlement. The field monitoring results and predicted values agreed very well.
Failure Of Micaceous Waste Tailings Dam, W. F. Brumund
Failure Of Micaceous Waste Tailings Dam, W. F. Brumund
International Conference on Case Histories in Geotechnical Engineering
The paper describes the failure and reconstruction of an 80 ft. high, 8 acre tailings impoundment in Western North Carolina. The darn was constructed using the upstream method of construction. The coarse fraction of the tailings was used as embankment construction materials; these consisted of coarse to fine sands. The fine fraction tailings consisted of low density, relatively low plasticity, layered fine sands and fine sandy silts with frequent inter bedding of micaceous silty clays. Although a 20.0 ft. section of the darn failed, the fine saturated tailings did not liquefy but rather slumped into the breach. Reconstruction was complicated …
Lake Monona Causeway - Madison, Wisconsin, Usa, W. W. Warzyn, C. A. Stoll
Lake Monona Causeway - Madison, Wisconsin, Usa, W. W. Warzyn, C. A. Stoll
International Conference on Case Histories in Geotechnical Engineering
In 1965 and 1966, a 3,500’ long, hydraulically-placed, highway embankment was constructed over the very soft lakebed deposits of Lake Monona. The compressible deposits, which ranged in thickness from 40’ to 80’, included marl, organic silt and silty clay. An incipient shear failure occurred near the end of the 1965 construction season, necessitating embankment design and construction modifications. Pertinent slope stability and settlement data are summarized, as are time dependent changes in in-situ subsoil parameters. Measured settlements, which currently range from 3’ to more than 12’, agree well with basic consolidation theory and engineering predictions formulated at project inception. General …
Open Pit Mine Rock Dump Geotechnical Evaluation, Z. M. Zovodni, J. D. Tygesen, S. C. Pereus
Open Pit Mine Rock Dump Geotechnical Evaluation, Z. M. Zovodni, J. D. Tygesen, S. C. Pereus
International Conference on Case Histories in Geotechnical Engineering
Open pit mining generally involves moving large quantities of waste rock to disposal areas which are usually located near the mine. This waste rock must be disposed of in a safe, economical, and environmentally acceptable manner. The stability of the waste dump depends to a great extent on the physical properties of the underlying foundation. Information must be obtained to define and assess the strength, consolidation, distribution, topographic and hydrogeologic properties for the foundation materials. Methods for obtaining estimates of the material properties include: laboratory and field testing, back analysis, and indirect estimates from other material properties. Mining operations in …
Peculiar Behaviour Of The Manicouagan 3 Dam's Core, O. Dascal
Peculiar Behaviour Of The Manicouagan 3 Dam's Core, O. Dascal
International Conference on Case Histories in Geotechnical Engineering
The presence of some horizontal or subhorizontal zones of weakness (cracks or decompressed layers) led to high pressure development in the downstream part of the relatively wide till core of Manic 3 dam. A short description of the investigation works to determine the location of the weakness zones and an analysis of the causes which produced these zones are presented in this paper.
Performance Of A Stone Column Supported Embankment, R. R. Goughnour, R. D. Barksdale
Performance Of A Stone Column Supported Embankment, R. R. Goughnour, R. D. Barksdale
International Conference on Case Histories in Geotechnical Engineering
The proposed expansion of ramps connecting Interstate Route 664 with Interstate Route 64 at Hampton, Virginia involved numerous high embankments and bridge structures over marshlands. Potential problems of embankment stability and excessive long term, post construction settlements were further complicated by very strict environmental constraints on acceptable construction methods. The solution chosen was stabilization of the in situ soils by the installation of stone columns. A description is given of stone column design, construction, field embankment instrumentation, and embankment performance for the first two years of operation. Four theories for predicting settlements of stone column reinforced ground are briefly reviewed. …
Performance Of An Embankment On Peat, R. E. Olson
Performance Of An Embankment On Peat, R. E. Olson
International Conference on Case Histories in Geotechnical Engineering
A widely held view is that rates of compression of peats are controlled by secondary effects and thus cannot be analyzed using primary consolidation theory. Data are presented here for the time rates of settlement of an embankment on peat. Theoretical analyses based on laboratory vertical and radial flow consolidation tests, and utilizing a finite difference scheme, indicated that the soil had undergone a degree of mass flow and was disturbed during or before jetting of sand drains, but that the field settlements could be predicted rationally using primary consolidation theory.
Performance Of Trial Embankment On Soft Clay, T. Shibata, H. Sekiguchi
Performance Of Trial Embankment On Soft Clay, T. Shibata, H. Sekiguchi
International Conference on Case Histories in Geotechnical Engineering
This paper is concerned with the interpretation of the observed and predicted performances of a full-scale trial embankment, which was constructed for the design purposes regarding a new bypass road to be constructed over soft clay adjacent to existing structures. The prediction based on the finite element analyses and the determination of soil parameters are briefly outlined. The results of comparison show adequate agreement between the predicted and observed field time-dependent deformation behavior throughout the entire loading history. However, if the predictions from the present FE-analyses are made by using the soil parameters measured in the laboratory, a correction factor …
Powerhouse Slope Behavior, Fort Peck Dam, Montana, J. V. Hamel, G. S. Spencer
Powerhouse Slope Behavior, Fort Peck Dam, Montana, J. V. Hamel, G. S. Spencer
International Conference on Case Histories in Geotechnical Engineering
Landslides occurred in the Bearpaw shale slope adjacent to the powerhouses at Fort Peck Dam in the geologic past. Excavation of the slope toe for construction of reservoir outlet works in 1934 initiated progressive sliding of colluvium which continued to 1974. The active slide area had an average movement rate of 4 ft/yr from 1944-1945 and average movement rates of 1-2 ft/yr from 1953-1971. These movements caused no distress to the powerhouses or other facilities. In 1974, the slope was stabilized by excavating 1.6 x 106 cu. yd. of material, resulting in a 1 on 6 overall slope. A field …
Slide Stabilization With Gravel Trenches, E. G. Wardlaw, L. A. Cooley, A. E. Templeton, R. L. Fleming Jr.
Slide Stabilization With Gravel Trenches, E. G. Wardlaw, L. A. Cooley, A. E. Templeton, R. L. Fleming Jr.
International Conference on Case Histories in Geotechnical Engineering
A different method of slide stabilization using gravel trenches is described. The design, construction, and performance monitoring of the gravel trenches are discussed together with a history of the slide, description of the soils, and mechanism of failure. The applications and limitations of this method of slide stabilization are also evaluated.
The Delayed Failure Of A Large Cutting In Hong Kong, R. R. Hudson, S. R. Hencher
The Delayed Failure Of A Large Cutting In Hong Kong, R. R. Hudson, S. R. Hencher
International Conference on Case Histories in Geotechnical Engineering
A large cutting in decomposed granite failed after five days of dry weather following an extremely intense rainstorm in August 1982. The history of the slope and surrounding area is described and three theories that might explain the delayed nature of the failure are proposed.
The Failure Of A Cut Slope On The Tuen Mun Road In Hong Kong, S. R. Hencher, R. P. Martin
The Failure Of A Cut Slope On The Tuen Mun Road In Hong Kong, S. R. Hencher, R. P. Martin
International Conference on Case Histories in Geotechnical Engineering
The investigation and analysis of two landslides in a recently-constructed cut slope in weathered granite are described in detail. The failures are attributed partly to complex geological conditions which caused a perched water table to develop in the major scar. Adverse jointing contributed to the minor failure. The original site investigation was not sufficiently detailed to identify the important geological and hydrogeological aspects of the site. Conclusions are drawn with respect to the usefulness of back analysis for identifying failure mechanisms.
The Foundation Of The Right Bank In Wadi-Zarat Dam, M. A. Benltayf, M. Atalla, K. Rabah
The Foundation Of The Right Bank In Wadi-Zarat Dam, M. A. Benltayf, M. Atalla, K. Rabah
International Conference on Case Histories in Geotechnical Engineering
The geotechnical engineering characteristics of a calcareous crust formation are evaluated in order to determine the feasibility of its stability under the right bank of Wadi Zarat Dam. The crust is a rock similar, extremely heterogeneous, material with location of collapsing susceptibility when saturated. The formation is caverned and locally very permeable and can present a risk of losing the reservoir water, dissolution, settlement, and piping. In this case study, several alternatives to treat the crust formation are presented, discussed, and compared. Rational justifications for the adopted solution are given and the predicted performance during operation of the dam is …
Assessment Of Seismic Stability Of Earth Dams By Comparative Methods, Rodney J. Huang, Marshall L. Silver
Assessment Of Seismic Stability Of Earth Dams By Comparative Methods, Rodney J. Huang, Marshall L. Silver
International Conference on Case Histories in Geotechnical Engineering
Seismic stability of embankment dams and their foundations has been a major concern in recent years because of notable incidents such as the behavior of the Lower San Fernando dam in the San Fernando Earthquake. Sophisticated and involved analytical methods have been developed to study the behavior of dams in earthquakes. Predicted seismic behavior agrees well with measured seismic behavior in the few case histories that exist of seismically induced distress in dams. However, for many dams, the level of information or effort required for a complete sophisticated seismic analysis is not warranted. For such cases it is possible to …
Earthquake Damages To Earth Dams And Levees In Relation To Soil Liquefaction And Weakness In Soft Clays, W. S. Wang
Earthquake Damages To Earth Dams And Levees In Relation To Soil Liquefaction And Weakness In Soft Clays, W. S. Wang
International Conference on Case Histories in Geotechnical Engineering
In this paper, a number of case histories of typical earthquakes dams and levees which have been damaged by earthquakes occurred in past two decades in China are reported in some details along with data obtained from field and laboratory investigations as well as some analytical results. These damages are mainly due to liquefaction of saturated cohesionless or less cohesive soils and slippage in weak soft clays. It is concluded that, in order to avoid severe earthquake damages, earth dams and levees should be compacted to dense state and any liquefiable soils and weak soft clays in foundations should be …
General Report For Theme Five Case Histories In Geotechnical Earthquake Engineering, Gonzalo Castro
General Report For Theme Five Case Histories In Geotechnical Earthquake Engineering, Gonzalo Castro
International Conference on Case Histories in Geotechnical Engineering
No abstract provided.