Canal and River Levées

533 Pages·1982·9.458 MB·2-540\533

by  PAVOL PETER (Eds.)

Further titles in this series:
1. G. SANGLERAT, THE PENETROMETER AND SOIL EXPLORATION
2. Q. ZÀRUBA and V. MENCL, LANDSLIDES AND THEIR CONTROL
3. Ε. E. WAHLSTROM, TUNNELING IN ROCK
4. R. SILVESTER, COASTAL ENGINEERING, I and II
5. R. N. YOUNG and B. P. WARKENTIN, SOIL PROPERTIES AND BEHAVIOUR
ft. Ε. E. WAHLSTROM, DAMS, DAM FOUNDATIONS, AND RESERVOIR SITES
7. W F. CHEN, LIMIT ANALYSIS AND SOIL PLASTICITY
8. L. N. PERSEN, ROCK DYNAMICS AND GEOPHYSICAL EXPLORATION
Introduction to Stress Waves in Rocks
9. M. D. GIDIGASU, LATERITE SOIL ENGINEERING
10. Q. ZÂRUBA and V. MENCL, ENGINEERING GEOLOGY
11. H. K. GUPTA and B. K. RASTOGI, DAMS AND EARTHQUAKES
12. F. H. CHEN, FOUNDATIONS ON EXPANSIVE SOILS
13. L. HOBST and J. ZAJÎC, ANCHORING IN ROCK
14. B. VOIGT (Editor), ROCKSLIDES AND AVALANCHES, 1 and 2
15. C. LOMNITZ and E. ROSENBLUETH, SEISMIC RISK AND ENGINEERING DECISIONS
lft. C. A. BAAR, APPLIED SALT-ROCK MECHANICS, 1
The In-Situ Behavior of Salt Rocks
17. A. P. S. SELVADURAI, ELASTIC ANALYSIS OF SOIL-FOUNDATION INTERACTION
18. J. FEDA, STRESS IN SUBSOIL AND METHODS OF FINAL SETTLEMENT CALCULA-
TION
19. A. KÉZDI, STABILIZED EARTH ROADS
20. E. W. BRAND and R. P. BRENNER (Editors), SOFT-CLAY ENGINEERING
21. A. MYSLIVEC and Z. KYSELA, THE BEARING CAPACITY OF BUILDING FOUNDA-
TIONS
22. R. N. CHOWDHURY, SLOPE ANALYSIS
23. P. BRUUN, STABILITY OF TIDAL INLETS
Theory and Engineering
24. Ζ. BAZANT, METHODS OF FOUNDATION ENGINEERING
25. À. KÉZDI, SOIL PHYSICS
Selected Topics
2ft. H. L. JESSBERGER (Editor), GROUND FREEZING
27. D. STEPHENSON, ROCKFILL IN HYDRAULIC ENGINEERING
28. P. E. FRIVIK, N. JANBU, R. SAETERSDAL and L. I. FINBORUT (Editors), Ground Freezing
1980
Developments in Geotechnical Engineering 29
CANAL AND RIVER
LEVÉES
by
PA VOL PETER
Department of Civil Engineering,
Slovak Technical University,
Bratislava, Czechoslovakia
ELSEVIER SCIENTIFIC PUBLISHING COMPANY
Amsterdam - Oxford - New York - 1982
Scientific Editor
Prof. Ing. Dr. Stanislav Kratochvil, DrSc.
Reviewers
Prof. Ing. Vaclav Hâlek, DrSc.
Prof. Ing. Julius Soltész, CSc.
Published in co-edition with
VEDA, Publishing House of the Slovak Academy of Sciences, Bratislava
Distribution of this book is being handled by the following publishers
for the U.S.A. and Canada
Elsevier/North-Holland, Inc.,
52 Vanderbilt Avenue
New York, New York 10017
for the East European Countries, China, Northern Korea, Cuba, Vietnam and Mongolia
VEDA, Publishing House of the Slovak Academy of Sciences, Bratislava
for all remaining areas
Elsevier Scientific Publishing Company
1, Molenwerf
P.O. Box 211, 1000 AE Amsterdam, The Netherlands
Library of Congress Cataloging in Publication Data
Peter, Pavol
Canal and River Levées
(Developments in Geotechnical Engineering, 29)
Revised and updated translation of : Kanâlové a ochranné hradze.
Bibliography: p. 540
Includes indexes.
1. Earth dams. 2. Levées. 3. Embankments. I. Title. II. Series.
TC543.P4613 627'.42 81-9833
ISBN 0-444-99726-1 (Vol. 29) AACR2
ISBN 0-444-41622-5 (Series)
© Pavol Peter, Bratislava 1982
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise,
without the prior written permission of the publishers.
Printed in Czechoslovakia
PREFACE
The need has arisen for a comprehensive book for civil engineering designers.
A few books on canal embankments and levées do exist, but they either give
insufficient consideration to the many practical problems, or are limited to special
aspects. In this book, we intend to give a clear explanation of the fundamental
principles of canal embankments and levées calculation and design. It is assumed
that the designer has no prior knowledge of the subject, but has a good
understanding of mechanics and fluid dynamics.
The basis of this English version is the Slovak version, augmented in the first,
sixth and seventh chapter by recent work on dam design, engineering and
maintenance. Some fundamental principles are discussed and illustrated with
applications to practical situations. It is intended that the book can also be used as
a reference source.
The author is grateful to various contractors, organizations (mainly to Hydrocon-
sult, Bratislava) and individuals who permitted the use of their figures and tables.
Most of all, the author would like to thank Professor S. Kratochvil, Associated
Professor V. Hâlek, and Professor J. Soltéfcz for their valuable comments.
INTRODUCTION
Canal embankments and levées are amongst the world's oldest hydroengineering
structures. Their history began many thousands years ago, as is proven by the
remains found in all centres of ancient culture, especially in China, India, Egypt
and Mesopotamia. This fact often leads to the erroneous supposition that the long
history of this type of construction contributes to progress in this particular field of
civil engineering, which should logically have a certain superiority over other
younger branches of the science, for example, hydroelectric works. However,
a thorough study of the present state of the design and construction of levées and
canal embankments persuades us that the reverse is true.
This unfavourable situation is evidenced in the fact that neither modern scientific
knowledge about soil mechanics, hydrogeology and hydrology, nor even experi-
ence in modern construction technology, are taken sufficiently into account when
designing levées and embankments. If we consider the profiles of levées planned or
constructed over the last ten years, we see that new gains in our knowledge of the
functional properties of soils commonly used in earth dams, are ignored both from
the point of view of stability and from the possibilities of seepage and uplift control
in embankment subsoils.
From a comparison and study of older and newer canal embankment cross-sec-
tions, we can see the progress made in perfecting their construction, especially since
1935. At the same time, designers of levées and canal embankments are usually
complacent, drawing their knowledge from traditional earth structures alone. The
main source of learning is found in the treatment of dams, documented by the
international Paris-based organization, Commission Internationale des Grands
Barrages. This institution is systematically developing theory and reassessing
knowledge in this field, while other international societies, International Commis-
sion on Irrigation and Drainage in New Delhi, India and International Central
Board of Irrigation and Power devote themselves mainly to questions of hydraulics
and the wider aspects of irrigation. Drawing knowledge from traditional structures
leads to a simplistic view of planning problems. Drawing knowledge from dam
engineering leads, as with most problems, to an excessively perfectionist view of
their solution ; this results in a substantial increase in construction costs. Even so,
many of the problems remain unsolved, because, despite the relatively modest
12 INTRODUCTION
construction of canal embankments and levées compared with dams, they are not
easier to design. One reason for this is that, whereas for dams one profile is usually
chosen from a wide range, the choice is much more limited for levées. These have
to lie along the direction of water flow where geological conditions are often
complicated. This is true of embankments running through regions beset with
filtration anomalies, where it is necessary to choose active and passive protecting
elements to counter seepage according to totally different criteria from those for
dams.
This fact is extremely important for the further development of embankment
design. It shows that it is necessary to work through these particular problems and
indeed to abandon completely old seepage theories in favour of seeking flew ones.
We shall not be satisfied with past stability analyses of embankments; we shall
rework totally the theory of filtration stability in a subsoil which is based on laws
drawn from Darcy's equation, also the basis of the most commonly used criteria of
K. S. Bligh and E. W. Lane. Previously, these criteria have very often been used
even though they are not really suitable for assessing the real danger in the most
critical cases. We must also revise the idea that seepage, and sometimes the
quantity of springs along the embankment, comprise the main criteria for judging
the threat to the structure and whole surrounding area.
With regard to the inevitability of a reappraisal of our knowledge, we shall
concern ourselves fairly thoroughly with the theory of seepage and calculations of
stability, and also with examining the difficult geological conditions in the actual
subsoil of embankments, not only in completely ideal conditions. From this
standpoint, we also wish to analyse sealing methods and embankment-building
technology, but without losing sight of the fact that our main concern is with the
correct evaluation of dimensions, and solutions to the problems of embankments in
unfavourable geological conditions.
Canal embankments entirely define the upper flow profile of the canal, in order
for it to fulfil safely its function as an artificial water course. This function is laid
down by its basic aim to serve, and according to this we can distinguish between the
embankments of power-station supply canals, irrigation canals — supply and
distribution for the irrigation of land — and waterway canals.
These all present their own problems, especially in the demands of sealing
(protection of the seal in navigation canals) and in the technology of construction.
In this respect, the largest functional variation is found in irrigation canals, for
which we sometimes require impermeability (usually in supply canals) and
elsewhere find that permeability is of little importance (in distribution channels).
We avoid the problems of drainage channels since they are usually below level.
River levées (for the prevention of flooding of land and housing) have a varied
character which demands their inclusion. From the point of view of functional
construction, we can differentiate :
(1) special levées for the protection of housing, towns and land;
INTRODUCTION 13
(2) control levées by which the flow regime is regulated and directed, and the flow
direction controlled, mainly during floods but occasionally also for controlling
flows of ice and floating debris ;
(3) dykes around reclaimed land (overflowed structures and otherwise) for
improving land-usage conditions ;
(4) sea walls and dyke embankments — for protection against waves.
We direct our main attention at solving the problems of protecting control
levées, which we sometimes call anti-flood (or -inundation) dykes. However, we
shall first apply ourselves to common problems closely related to these structures.
SYMBOLS
a storage capacity of a layer (a = Tino) ; coefficient ; distance between two
objects (plates, layers, etc.)
A air content
Ar Archimedean number
b coefficient
Β width of footing; width of canal water
ß, Β pore pressure coefficients
c shear strength parameter; coefficient of hydraulic resistance
Ci coefficient of hydraulic friction
undrained (total stress) shear strength parameter
Cu
coefficient of consolidation ; surface area of dry packing per unit volume
Cv
C constant
a
coefficient of curvature
CD, CL coefficient of drag force and lift force
G coefficient of uniformity of soil
diameter; thickness of the layer (slab, lining, apron, etc.);
length od drainage path ; diameter of grain which can be carried out by
seepage water
</, diameter of sediment particle or of particle with characteristic specific
surface
D depth of footing ; depth below drains to the impermeable layer ; distan-
ce ; thickness of the layer
degree of density and relative density
e distance ; void ratio ; expansion
E energy; Young's modulus
total active thrust ; total passive resistance of earth
modulus of elasticity (after Hooke)
) error function complementary of u=—-= I exp ( — z2) dz
f factor of mechanical friction
hydraulic friction factor
F force ; hydrodynamic force
seepage force
SYMBOLS 15
Fr Froude number
g acceleration due to gravity 9.81 m s~2 (force per unit mass due to
gravity)
G weight of the body
G specific gravity of solid particles ; gravity parameter (G = t> : υ)
s s s
G? gravity parameter ; v related to fictive velocity
s
h water elevation difference between two positions s and s (Hi — H)
0 2
As water elevation difference between exit free water surface and water
table in the well (or ground surface)
H height ; potential energy related to weight of mass — H=p: (gg + h) ;
total elevation difference
/ unit vector in the χ coordinate direction
i material commodity index
m
/ hydraulic gradient ; integral value
7 index of liquidity
L
7p index of plasticity; pressure gradient
/ unit vector in the y coordinate direction, vertical coordinate
/ integral, seepage force
k coefficient of permeability ; the unit vector in the ζ coordinate direction
ko, k k coefficients of permeability according to Darcy (after empirical formulas
u {)
and other)
k, Κ coefficients of permeability in horizontal and vertical directions
h
/, L length ; the direct distance between the ends
m factor of safety (in mechanical stability computation)
M mass
η porosity
n effective porosity
cU
Ν number of equipotential drops
N number of low channels
{
ρ pressure of the liquid (water) ; normal load
/?* piezometric pressure — potential energy related to value p* = p + ggh
Ρ total pressure
P, P total active thrust and total passive resistance (earth pressure)
a p
PI plasticity index
PL(Wp) plasticity limit
q volume of water flowing per unit time (through unit cross-sectional
area) ; volume flux ; surface pressure ; total foundation pressure of the
structure
q specific seepage quantity (q = q: kH)
q* superficial (fictive) velocity
Ο total flow per unit time ; discharge ; surface load
R resistance
16 SYMBOLS
R, r radius, and radius of the small tube (capillary)
R hydraulic radius
H
s path of seepage ; settlement ; total unit of shear strength ; shear strength
5 surface ; cross-sectional area ; degree of saturation ; sand
SF safety factor
t time ; thickness of the sealing
Τ transmissivity of aquifer (T=kD)
T tortuosity of pore channels
k
T time factor of vertical drainage
y
ü average velocity
w, w pore water pressure
w
w pore air pressure
a
U potential of volume forces ; uplift water force ; degree of consolidation
ν discharge velocity
v'f seepage velocity
v fall velocity — settling velocity of a solid particle in a fluid due to gravity
s
V volume ; total velocity vector
w water content ( w — natural, Wopt — optimum)
n
w , W liquid and plastic limits
L P
Χ, Υ, Ζ components of the body force (forces) in the JC, y, ζ axis directions
ζ depth coordinate ; vertical coordinate ; elevation head
a slope angle ; coefficient of drainage effect of a bore hole
β slope angle
γ unit weight
γ' Buoyant unit weight of soil
γ dry unit weight of soil
ά
y unit weight in natural conditions (in the field)
n
/sat saturated unit weight
y unit weight of water
w
δ angle of friction between two different materials
op portion of sand filled in pores of gravel
S heterogeneity coefficient
s
η dynamic viscosity *
6 function of Youkowski
χ relationship
λ modulus of eliptic integral
ν kinematic viscosity
η, ζ horizontal (§, η) and vertical (ζ) coordinates
ρ bulk density
Q dry density
D
Q density of solid particles
S
ρ ι saturated soil density
8β