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Articles 131161 - 131190 of 136202
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Grand Coulee Riverbank Stabilization – Case History Of The Design Of Remedial Measures, J. Lawrence Von Thun
Grand Coulee Riverbank Stabilization – Case History Of The Design Of Remedial Measures, J. Lawrence Von Thun
International Conference on Case Histories in Geotechnical Engineering
Planned peaking operations at Grand Coulee Dam will cause river fluctuations of up to 1 feet daily for the authorized plant and up to 38 feet daily for a proposed plant expansion. Treatment of the historically unstable riverbanks was required to offset the destabilizing effect of the peaking operations. Consideration of the geologic history of the bank materials, estimation of future pore pressure conditions, formulation of the stabilization criteria, and the success in reducing pore pressure levels in varved clays in the bank were some of the important aspects of this project.
Performances Of Some Embankment Dams In India, T. Ramamurthy
Performances Of Some Embankment Dams In India, T. Ramamurthy
International Conference on Case Histories in Geotechnical Engineering
The performance in terms of pore pressure and deformation of five earth and earth-rock-fill dams is briefly presented. These darns are located in different geologic formations. Their pore pressure response has been low due to relatively longer construction periods. The deformation behaviour has been similar to the dams constructed earlier. The valley ratio seems to influence the strain condition along the height and longitudinal axis of the embankment darn.
Quest And Probe Related To Erosion In The Wrap-Around Of An Embankment, R. J. R. Cardia
Quest And Probe Related To Erosion In The Wrap-Around Of An Embankment, R. J. R. Cardia
International Conference on Case Histories in Geotechnical Engineering
CESP's divers team found several basalt blocks scattered on the stilling basin of a power plant. Water flowing through bottom outlets was initially supposed to cause erosion in the upstream rip-rap of the wrap-around. Events chronologically reported are: Underwater inspection; removal of materials; monitoring devices behavior; hydraulic tests. Hinder analyses led to recognition of misunderstanding on anomalous mechanism and misconception on the actual sources for the hauled rubbish.
Reconsideration Of Failure Initiating Mechanisms For Teton Dam, G. A. Leonards, L. W. Davidson
Reconsideration Of Failure Initiating Mechanisms For Teton Dam, G. A. Leonards, L. W. Davidson
International Conference on Case Histories in Geotechnical Engineering
A review of failure mechanisms previously suggested for Teton Dam indicated that they were not fully supported by all the available data. The original mechanisms are reviewed and a failure initiation mechanism is then proposed which does satisfy all the available data, and laboratory tests supporting this mechanism are presented. Additional lessons to be learned from the failure are listed.
Slip Failure Of Embankment On Soft Marine Clay, K. Y. Yong, S. T. Ting
Slip Failure Of Embankment On Soft Marine Clay, K. Y. Yong, S. T. Ting
International Conference on Case Histories in Geotechnical Engineering
The results of an investigation carried out at a site before and after the slip failure of an embankment on soft marine clay are presented. An evaluation of the possible causes for the slip failure and the remedial measures taken after the failure are also included. It appears that overstressing of the ground might have led to the movement of the soft soil. The compressible soils were subjected to an increase in stress without a comparable increase in foundation shear strength. This increase in horizontal stress resulted in the horizontal displacement of the soil as evident by the presence of …
Stability Of An Erratic Tailings Deposit, P. C. Kotzias, A. C. Stamatopoulos, B. Karas
Stability Of An Erratic Tailings Deposit, P. C. Kotzias, A. C. Stamatopoulos, B. Karas
International Conference on Case Histories in Geotechnical Engineering
150 million cubic meters of erratic colliery spoils were deposited between 1971 and 1983 close to the Kardia lignite fields, in Greece. The heap finally reached satisfactorily an escalating height of 73 m. Field reconnaissance, collation of local experience and geotechnical investigations were performed during midstage of deposition. They aimed at an optimal configuration of the fill in progress, within the possibilities allowed by extensive earth moving operations. Present paper out- 1ines the approach and the methodology used to arrive at strength parameters and slope design of a highly inhomogeneous massive comprising variegated soils, marls and encaptured lignites.
Stability Of Hill Slopes And Foundation Condition At Radio Astronomy Centre Ootacamand, R. K. Katti, V. S. Chandrasekaran, A. Parthasarathy, K. K. Moza
Stability Of Hill Slopes And Foundation Condition At Radio Astronomy Centre Ootacamand, R. K. Katti, V. S. Chandrasekaran, A. Parthasarathy, K. K. Moza
International Conference on Case Histories in Geotechnical Engineering
Stability aspects of hill slopes and foundation considerations of Radio Astronomy Centre at Ootacamand are described. The analysis of slopes indicated that if joints are not covered, the material in joints may lose strength and the slopes may enter a state of instability. Footings with inclined legs were found to resist the horizontal forces, pull and overturning movements. Lime piles adopted for strengthening soft material at one of the tower locations were found to be effective.
Stability Of Shannon Embankments, K. R. Massarsch, M. O. Fives
Stability Of Shannon Embankments, K. R. Massarsch, M. O. Fives
International Conference on Case Histories in Geotechnical Engineering
During the operating life of the Shannon Embankments, stability and seepage problems have occurred which caused concern regarding long term safety. The geology was studied, a comprehensive scheme of field and laboratory investigation was undertaken and the stability was analyzed and back calculated under failure conditions. The relative significance of various parameters was studied and provided the basis for the design of remedial measures. This paper deals in detail with the study of the stability of one embankment section (Fort Henry) and the recommendations on remedial measures.
The Santa Helena Dam On Compressible Foundation, Vinod K. Garga, Arnaldo V. Rocha, Homero G. Ramos
The Santa Helena Dam On Compressible Foundation, Vinod K. Garga, Arnaldo V. Rocha, Homero G. Ramos
International Conference on Case Histories in Geotechnical Engineering
The Paper describes the performance of a 28 m high compacted earthfill dam for water supply in Northeast Brazil. For mainly economic reasons, the dam was founded, in part, over soft to very soft silty clays to a depth exceeding 8 metres. Large diameter sand drains were provided to accelerate consolidation in the foundation during construction. Maximum construction settlements of approximately 240 cm were recorded. Results of settlement of spillway structures, pore pressure measurements in the fill and long term settlements, are described in this paper. Transverse cracking of fill occurred as a result of large deformations in the compressible …
The Use Of Limited Field Observation In Remedial Design, J. P. Sully, G. I. Mcphail
The Use Of Limited Field Observation In Remedial Design, J. P. Sully, G. I. Mcphail
International Conference on Case Histories in Geotechnical Engineering
As a consequence of a slope failure, an investigation was carried out to determine the present and future stability of a gold tailings dam in the Orange Free State, South Africa. Recommendations were also required concerning the type of remedial measure(s) necessary in order to permit continued deposition of the tailings waste product on the dam. The field and laboratory investigation involved sampling of the tailings and foundation soils and installation of piezometers at various locations around the dam. The paper describes how, using data obtained from a limited monitoring period, evaluation of in-situ parameters enabled prediction of future phreatic …
Guest Lecture – Foundation Engineering For Gravity Structures In The Northern North Sea, Ove Eide, Knut H. Andersen
Guest Lecture – Foundation Engineering For Gravity Structures In The Northern North Sea, Ove Eide, Knut H. Andersen
International Conference on Case Histories in Geotechnical Engineering
During the past 10 years, 15 gravity structures have been installed in the northern North Sea. As new gravity structures are being designed for installation on softer soils and at greater depths, they still pose a great challenge to soil mechanics and foundation engineering. Great improvements have been made during the 10-year period. This applies to soil investigations, in-situ measurements, undisturbed sampling, laboratory testing and design analyses. Compared to structures on land, offshore gravity structures are characterised by large foundation areas, the installation method, and the cyclic wave loading state. The paper reviews investigation methods, site and soil conditions, construction …
Rock Borer Attack On Juaymah Trestle Concrete Piles, E. A. Wiltsie, W. C. Brown, K. Al-Shafei
Rock Borer Attack On Juaymah Trestle Concrete Piles, E. A. Wiltsie, W. C. Brown, K. Al-Shafei
International Conference on Case Histories in Geotechnical Engineering
Rock boring mollusks and sponges are infesting the concrete cylinder piles supporting the Juaymah NGL Trestle located in the western Arabian Gulf. The calcareous aggregate used in pile fabrication provides a favorable substrate for borer activity. Rock boring organisms are common in the Arabian Gulf and typically inhabit nearshore reefs and exposed limestone bottom areas. Although the entire trestle wetted area is subject to attack, infestation is concentrated in the area adjacent to reefs and limestone, on the down current pile face and near the water surface. Boring organisms pose a significant threat to the trestle structural integrity, in that …
A Comparison Of Methods Of Estimating The Attenuation Of Earthquake Strong Ground Motion, O. W. Nuttli, R. B. Herrmann
A Comparison Of Methods Of Estimating The Attenuation Of Earthquake Strong Ground Motion, O. W. Nuttli, R. B. Herrmann
International Conference on Case Histories in Geotechnical Engineering
Strong ground-motion attenuation relations take on a variety of forms, depending upon the parameters used to express the relations and upon the geographic area for which the equations are developed. In general the strong ground-motion parameters, namely acceleration, velocity, displacement and response spectra ordinates, are taken to be proportional to the distance from the earthquake source to the site, to the magnitude or some measure of the strength of the earthquake source, and to loss factors resulting from transmission of energy through the inelastic earth. In certain areas of the world, where strong-motion data are abundant, empirical relations can be …
A Geotechnical Study For Land-Use Planning Purposes, F. Ciuffi
A Geotechnical Study For Land-Use Planning Purposes, F. Ciuffi
International Conference on Case Histories in Geotechnical Engineering
The purpose of this paper is to describe the different stages and the final results of a geotechnical study for use by planners in zoning a seismic area in the south of Italy. Particular attention is given the method followed to draw a “Geotechnical Seismic Zoning Map”. Also described in summary fashion are a number of dynamic laboratory tests carried out and their results.
Assessment Of Earthquake Size From Rock Fracture Dimensions Of Seismic Source In Geotechnical Earthquake Engineering Investigations, L. S. Srivastava
Assessment Of Earthquake Size From Rock Fracture Dimensions Of Seismic Source In Geotechnical Earthquake Engineering Investigations, L. S. Srivastava
International Conference on Case Histories in Geotechnical Engineering
The paper presents two case histories of rock fractures resulting in strong ground motion. Case I describes the November 27, 1971 rock burst involving 270 m long rupture with displacement of 15 mm in Nundydroog mine in Kolar Gold Field in Karnataka State, India, which resulted in damage to buildings on the surface and underground works in the mine. The event was recorded as an earthquake by seismic stations and the computed magnitude ml = 3.9 of the rockburst compares well with magnitude mb= 4.6 determined from the recorded seismogram. Case II describes April 5, 1976 rock …
Behavior Of Some Earth Dams On Liquefiable Soil, A. Popovici, V. Perlea, L. Corda
Behavior Of Some Earth Dams On Liquefiable Soil, A. Popovici, V. Perlea, L. Corda
International Conference on Case Histories in Geotechnical Engineering
The 1977 March 4 Vrancea earthquake emphasized several zones with liquefiable materials on Romanian territory. Some earth dams of such zones, placed to over 200 km from the earthquake epicenter were damaged. Important hydropower works are at present in different design or construction stages in such area, comprising long earth dams. The Seismic analysis procedure applied to their design was based on the finite element method. Some characteristic cross - sections of the earth dams in different versions have been studied. The analysed sections had different shapes (with and without stabilizing benches downstream) and included different zoning of the materials …
Pile Foundations Under Liquefied Soils, Liu Huishan, Qiao Taiping
Pile Foundations Under Liquefied Soils, Liu Huishan, Qiao Taiping
International Conference on Case Histories in Geotechnical Engineering
The Tangshan and Haichen earthquakes gave engineers a chance to examine the aseismic behaviors of various structures and provided valued information for further revision of aseismic regulations. The results of investigation of pile foundations resting on potentially liquefied soils herein presented. In addition, some supplementary laboratory tests were also performed to clarify some phenomena. Based upon the investigation in situ and shaking table tests authors made some analysis and comments on pile foundation design in this paper.
Post-Earthquake Failure Of A Tailings Dam Due To Liquefaction Of Pond Deposit, Kenji Ishihara
Post-Earthquake Failure Of A Tailings Dam Due To Liquefaction Of Pond Deposit, Kenji Ishihara
International Conference on Case Histories in Geotechnical Engineering
At the time of the Izu-Ohshima-Kinkai earthquake of January 15, 1978 in Japan, two darns retaining tailings from Mochikoshi gold mine failed, leading to a release of a large volume of tailings. One of the darns, No.1 dike, collapsed almost simultaneously with the shaking of the main shock, but another darn, No.2 dike, failed about 24 hours later at a time when there was no shaking. The failure of the No.1 dike is known to have been triggered by the liquefaction which developed in the tailings deposit in the impoundment pond. The cause of the failure in the No.2 dike …
Seismic Motion Selection Criteria For Dam Design, G. Rodolfo Saragoni
Seismic Motion Selection Criteria For Dam Design, G. Rodolfo Saragoni
International Conference on Case Histories in Geotechnical Engineering
In recent years, new seismic design methods for earthdam, based on finite element have been used. These methods generally require selection criteria of seismic ground motion to be used for the design. Most standard criteria used are maximum ground acceleration and linear response spectra. These criteria fail to predict seismic dam response due to strong nonlinear soil behavior characterized by large permanent displacement, shear modulus degradation and damping increasing with shear strain deformation variation, increase of water pore pressure and large variation of natural period of dam. A criterion based on the potential destructiveness of earthquake motion is proposed. This …
Seismic Response And Liquefaction Analysis By An Approximate Method, M. Hyodo, T. Yamanouchi, J. Hashizume
Seismic Response And Liquefaction Analysis By An Approximate Method, M. Hyodo, T. Yamanouchi, J. Hashizume
International Conference on Case Histories in Geotechnical Engineering
Presented is a simplified procedure for performing the dynamic effective stress analysis. An equivalent linear method is applied to the procedure. It is assumed, in this method, that the variations of the shear modulus and damping factor due to strain level and effective stress are independent one another. That is, firstly the total stress analysis is done in order to obtain the effective strain. Then the effective stress analysis is carried out and the moduli are varied due to the variation of the effective stress only. The accuracy of the result is checked by comparing it with that of nonlinear …
Surface Damage Of Tangshan Earthquake And Characteristics Of Response Spectrum Of Ground Movement, S. D. Zhao, H. Q. Fang
Surface Damage Of Tangshan Earthquake And Characteristics Of Response Spectrum Of Ground Movement, S. D. Zhao, H. Q. Fang
International Conference on Case Histories in Geotechnical Engineering
The intensive ground movement of seismic region was an essential factor in causing ground damages. Damages in historical events signified that the extent of destruction not only conformed to the epicentral distance but also related to geomorphology, soil type and ground structure. Different combination of ground lithology may reflected directly the enhancement and attenuation of seismic wave during its propagation and it had also dominating influence on ground movement, different damages and seismic excitation of the same ground. Hence the amplitude and type of seismic response spectra were determined. In this paper, ground movement and damage feature on geomorphology units …
The Role Of Case Studies In The Evaluation Of Soil Liquefaction Potential, H. Bolton Seed
The Role Of Case Studies In The Evaluation Of Soil Liquefaction Potential, H. Bolton Seed
International Conference on Case Histories in Geotechnical Engineering
Field evidence concerning soil liquefaction is reviewed and a number of case studies are summarized. Examples of the use of case studies in developing an understanding of the liquefaction phenomenon, both on level ground due to earthquake shaking and in slopes due to earthquake and static stress applications are presented.
Dynamic Response And Static Analysis Of Rcc Space Frames Supporting High Speed Centrifugal Machines With Coupled Soil-Structure Interaction, Dilip K. Chakravorty, Dhiman K. Ghosh, H. N. Batavyal
Dynamic Response And Static Analysis Of Rcc Space Frames Supporting High Speed Centrifugal Machines With Coupled Soil-Structure Interaction, Dilip K. Chakravorty, Dhiman K. Ghosh, H. N. Batavyal
International Conference on Case Histories in Geotechnical Engineering
The paper reviews the current state of the art on the dynamic and static analyses of RCC space frames supporting high speed centrifugal machines e.g. large turbogenerators and compressors. The need to include the effects of soil-structure interaction formulations on overall behaviour of various analytical models are highlighted, At the same time, the uncertainties involved in evaluating essential geotechnical parameters and paucity of reliable and elaborate information from the machine manufacturers are discussed. The analysis and design aspects of this inter-disciplinary problem are illustrated with two typical design case studies selected from authors’ own experience in this specialised field. The …
Forge Hammer Foundation On Dilative Soil, S. J. Yang
Forge Hammer Foundation On Dilative Soil, S. J. Yang
International Conference on Case Histories in Geotechnical Engineering
The property of dilative soil will further change when the dynamic force with different frequency acts on soil surface. So far, the physical process of this change remains unknown. However, it has been observed in the field test that dynamic force would increase the amount of the crevice of dilative soil and destroy the soil by combining with the external water.
Foundation-Bearing-Rotor Interaction Problem In Controlling Vibrations In A 120 Mw Turbo Generator, Krishen Kumar, Shamsher Prakash
Foundation-Bearing-Rotor Interaction Problem In Controlling Vibrations In A 120 Mw Turbo Generator, Krishen Kumar, Shamsher Prakash
International Conference on Case Histories in Geotechnical Engineering
A two-pole turbogenerator posed problem of resonance and excessive vibrations at the operating speed during test runs in the Test-bed. The entire system comprising the foundation, pedestals supporting the generator, journal bearing seats, bearing oil-film, and the rotor has been modeled and analysed for computing the rotor's critical speeds as also the foundation's natural frequencies. Some of the system's parameters have been derived from actual tests. Sensitivity analysis for the rotor's critical speed that coincided with the operating speed of machine showed that this critical speed is relatively insensitive to the foundation mass as well as stiffness, and largely depends …
General Report For Theme Six – Case Histories In Machine Foundations, Richard D. Woods
General Report For Theme Six – Case Histories In Machine Foundations, Richard D. Woods
International Conference on Case Histories in Geotechnical Engineering
No abstract provided.
Machine Foundations In Power Plant And Other Industries- Case Studies, K. G. Bhatia
Machine Foundations In Power Plant And Other Industries- Case Studies, K. G. Bhatia
International Conference on Case Histories in Geotechnical Engineering
Studies on dynamic behaviour of turbo-generator foundations of various ratings have been carried out. Salient response parameters have been identified, Field vibration measurements taken on a 200 MW T.G. foundation have been reported. Measurements taken under intermittent coast-up and constant speed conditions have been analysed using FFT analyser and the frequency response thus obtained has been presented and discussed. From the signature analysis, high vibration peaks associated with the soil vibration modes have been observed. Analytical study carried out for 200 MW TG foundation also indicated the significance of soil structure interaction effect on the dynamic response. Based on the …
Vibration Studies Of Block Type Machine Foundations, S. K. Guha
Vibration Studies Of Block Type Machine Foundations, S. K. Guha
International Conference on Case Histories in Geotechnical Engineering
Detailed vibration measurements were undertaken at eight block type machine foundations with different supporting soil conditions. These extensive measurements were supplemented by theoretical vibration calculations using principally Barkan's method but, at times, using methods of Reissner, Pauw, Richart and Ford and Haddow. The results of prototype experiments and theoretical studies on various compressor foundations described above as also on similar foundations in the country justify broadly the validity of various theories, particularly Barkan’s method, though these are based on somewhat different concepts. Design criteria for foundations are generally described in terms of limiting values of amplitudes of displacement at the …
General Report For Theme Seven – Case Histories In Rock Mechanics, Alfred J. Hendson Jr.
General Report For Theme Seven – Case Histories In Rock Mechanics, Alfred J. Hendson Jr.
International Conference on Case Histories in Geotechnical Engineering
No abstract provided.
Mechanised Rock Tunneling In Adverse Conditions, I. Mcfeat-Smith
Mechanised Rock Tunneling In Adverse Conditions, I. Mcfeat-Smith
International Conference on Case Histories in Geotechnical Engineering
Several case histories are presented in order to highlight the way in which unexpected adverse geological conditions promote large delays in rock tunnelling. These are selected from tunnels which have been excavated by drill and blast, roadheader and fullface tunnel boring machines. In each case the important properties of rock affecting the progress rates obtained are identified together with the nature of the tunnelling problems encountered.