SURFACE STRUCTURES:DAMS & EMBANKMENTS
approach embankment. The design of piles loaded by lateral
soil movements is problematic in that existing design
approaches are generally inconsistent or show poor correlation with available data. New empirical design charts are
presented to allow an assessment of maximum pile bending
moment and pile head deflection based on the relative soilpile stiffness and current loading level. A new analytical
approach is also developed on the basis of a simple
deformation mechanism. The method accounts for the main
features of the problem through an approximate representation of the embankment-soil-pile interaction, and is shown to
compare favourably with centrifuge model test data. Recommendations for the design of pile groups for loading from
lateral soil movements are also given. (Authors)
951236
Lateral load capacity of single piles in sand
M. Mahmoud & E. Burley, Proceedings ICE: Geotechnieal
Engineering, 107(3), 1994, pp 155-162.
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This paper investigates the behaviour of single unrestrained
(flee-headed) scale model piles installed vertically in a
cohesionless seabed sand, subjected to static lateral loading.
A study is made of some of the parameters which influence
the lateral load capacity of single piles; these are breadth,
depth of embedment and the cross-sectional shape of the pile.
Variations of lateral load with the above parameters show
that the behaviour of laterally loaded piles is essentially
controlled by all of these parameters. In order to illustrate
these relationships further, test results are presented in terms
of Broms dimensionless groups H/~'KpB' and LIB for
different stages of loading corresponding to different pile
head lateral displacement ratios (x/B). (from Authors)
951237
Lateral load analysis of mingle piles and drilled shafts
J. M. Duncan, L. T. Evans Jr & P. S. K. Ooi, Journal of
Geotechnieal Engineering - ASCE, 120(6), 1994, pp 10181033.
The p-y method of analysis models nonlinear behavior, and is
an effective method of designing deep foundations subjected
to lateral loads. Deflections and bending moments calculated
using p-y analyses have usually been found to he in good
agreement with field measurements. This paper describes a
method of analysis, the characteristic load method (CLM)
that is simpler than p-y analyses, but that closely approximates p-y analysis results. The method uses dimensional
analysis to characterize the nonlinear behavior of laterally
loaded piles and drilled shafts by means of relationships
among dimensionless variables. (from Authors)
33A
Dams and embankments
951239
Detection of water leakage from dams by self-potential
method
N. H. AI-Saigh, Z. S. Mohammed & M. S. Dahham,
Engineering Geology, 37(2), 1994, pp 115-121.
A self-potential survey of streaming potentials along the
eastern embankment of a dam was very successful in locating
leakage areas and determining the relative intensity of
discharge. Self-potential measurements have shown negative
anomalies of up to 100 mV in amplitude. The width of the
discharge areas ranged between about 40 m and 150 m.
Repeated observations of SP data at two different reservoir
levels showed no great change in the leakage flow behaviour.
(from Authors)
951240
The practice of developing criteria of the safe state of an
earth dam with respect to slope stability
N. A. Kxasil'nikov, Hydrotechnical Construction, 27(12),
1993, pp 732-737; translated from: Gidrotekhnieheskoe
Stroitel'stvo no. 12, 1993, pp 43-47.
This article examines how to develop graphs or dependences
making it possible to establish on the basis of the water level
in piezometers the value of the stability factor of a dam slope
at a specific time and, in particular, to determine the
maximum allowable values of the water level in piezometers
corresponding to the standard value of the slope stability
factor in all operating regimes of the structure. The values of
the maximum allowable indices (MAIs) developed for piezometers installed on structures provide a prompt evaluation of
the state of the dam by operating personnel and can be used
when analysing and interpreting the data of on-site measurements by monitoring and measuring instruments on earth
dams. A method is given for developing the MAIs, the
composition of the accompanying topographic and survey
works, geotechnical and other investigations is shown. The
introduction fo these recommendations into practice will
promote a decrease of the failure rate of earth dams. (from
Authors)
951241
Formulation of hydrodynamic pressures in cracks due to
earthquakes in concrete dams
R. Tinawi & L. Guizani, Earthquake Engineering &
Structural Dynamics, 23(7), 1994, pp 699-715.
A new analytical development of the seismic hydrodynamic
pressure inside pre-existing cracks on the upstream face of
concrete dams is presented. The finite control volume
approach is utilized to derive an expression for the seismic
hydrodynamic pressure using the continuity principle and the
linear momentum theorem for the fluid inside the crack. The
derived pressure expression is a function of the relative crackopening acceleration and velocity. (from Authors)
951238
Lateral load analysis of g r o u p of piles aod drilled shafts
P. S. K. Ooi & M. Duncan, Journal of Geotechnical
Engineering. ASCE, 120(6), 1994, pp 1034-1050.
951242
Reliability analysis of sediment control steel dams
S. Katsuki & D. M. Frangopol, Structural Safety, 15(1-2),
1994, pp 131-148.
This paper presents a simple method (the group amplification
procedure) for estimating pile group deflections and maximum bending moments. The method is applicable to groups
of drilled shafts as well as groups of piles. Group lateral
deflections and the maximum bending moment in the most
severely loaded pile in the group are estimated by multiplying
the values for single piles by amplification factors (which have
values larger than unity). (from Authors)
This study presents a reliability analysis method for sediment
control steel dams under rock impact loading. Because of the
ability to develop significant postelastic deformations prior to
failure, sediment control steel dams are analyzed by the
incremental elastoplastic approach. The proposed method
takes into account the axial-bending-torsional interaction as
well as all uncertainties associated with the loading, including
impact location, impact angle, rock mass, and rock velocity.
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