Upload
others
View
13
Download
0
Embed Size (px)
Citation preview
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
Experimental Investigations of Local Scour around
Mahanadi Bridge Piers Using HEC-RAS 5.0.0
Sriparna Paul1
1Assistant Professor, Department of Civil Engineering,
Bhubaneswar Institute of Technology, Bhubaneswar, Odisha, India.
ABSTRACT
Engineering is typically concerning avoiding failures and investigation why failures occur and ways that
to repair the matter. There is a desire to know the conditions giving rise to past failures and ways that
to avoid such failures in order that loss of life will be reduced. The hydraulic structures are crucial
structures that necessitates a significant asset to build and serves a vital risk in monetary growth. Thus,
the hydraulic bridges must be protected from the breakdown by non-stop supervising, safeguarding and
suggesting a few mandatory refurbish works. For this reason, this research is on the subject of the
major universal reasons of bridge collapse which is the local scour. In this research, Hydrologic
Engineering Centre River Analysis System (HECRAS) Program was adapted in order to estimate local
scour around the bridge piers. For this research to go smoothly, one of the major bridge was well
thought out i.e. Mahanadi bridge. The Mahanadi Bridge was built up over the Mahanadi River. This
bridge is one of the oldest structure in Odisha state and therefore, their impacts should be pre-
meditated and evaluated. The collision of the bridge construction are estimated from the bed analysis
during different periods including the latest hydrographical survey for the river Mahanadi in the middle
of the Odisha. This paper investigates the behavior and the failure mechanism of the bridge both of the
time using HECRAS Model. To be aware of the characteristics of bridge failures under scour conditions
and supply helpful information for scour step. This paper describes the failure causes and suggests
engineering lessons to be learned and also compares well between the computed scour depth from the
HECRAS Program and the observed value.
Keywords: Bridge Collapse, Bridge Piers, HEC-RAS, Hydrographical survey, Local Scour, Local scour depth,
Mahanadi Bridge, Mahanadi River.
Page 61 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
I. INTRODUCTION
The bridge failures result in excessive repairs, loss
of accessibility, or even death (Chiew, 1995).The
potential cost including human toll and monetary
cost of bridge failure due to scour damage has
highlighted the need for scour protection/reduction
methods. A large depth of foundation is required
for bridge piers to overcome the effect of scour
which is a costly proportion. Therefore, for safe and
economical design, scour around the bridge piers is
required to be controlled. The bridge piers require
deep and expensive pier embedment in rivers. To
reduce this depth of embedment, efforts have been
made by armoring devices like the riprap around
the pier (Brice et. al., 1978; Croad, 1993;
Parola,1993; Yoon et. al., 1995; Worman 1989,
(Lim and Chiew, 1996 and 1997); Lim, 1998;
Chiew and Lim, 2000; Lim and Chiew, 2001) and
by flow altering devices like an array of piles in
front of the pier (Chabert and Engeldinger, 1956
and Melville and Hadfield,1999), a collar around
the pier (Schneible, 1951; Thomas 1967; Tanaka
and Yano 1967; Ettema 1980; Chiew, 1992; kumar
et. al., 1999, Zarrati et. al., 2004, Zarrati et. al.,
2006), submerged vanes (Odgard and Wang 1987),
a delta-wing-like fin in front of the pier (Gupta and
Gangadharaiah, 1992), a slot through the pier
(Chiew, 1992; Kumar et. al., 1999) and partial pier-
groups (Vittal et. al., 1994).
II. FLOW PATTERN AND MECHANISM OF
SCOURING
The vortex system and down-flow are the principal
causes of local scour. At the upstream face of the
pier, the approach flow velocity goes to zero. This
causes an increase in pressure. Due to this
phenomenon the water surface level in front of pier
increases. As the flow velocity decreases from the
surface to the bed, the dynamic pressure on the pier
face also decreases downwards. The downflow digs
a hole in front of the base of the pier, rolls up and
by interaction with the coming flow forms a
complex vortex system (Fig.1.)
Figure 1: Diagrammatic flow pattern at a
cylindrical pier
Flow altering devices can be more economical,
especially when the riprap material in required
amount is not available near the bridge site or is
expensive. However, there are certain limitations on
the use of these flow altering devices to reduce the
scour depth at piers. A slot may be blocked by
floating debris. In addition to this, its construction
Page 62 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
is difficult. Sacrificial piles may become ineffective
when the flow approaching the piers changes its
direction. A thin collar plate skirting around bridge
piers (Fig. 2) at or below the bed level which
diverts the down flow and shields the streambed
from its direct impact is therefore, a very effective
mean of protection against scour.
Figure 2: Collar around round nosed rectangular pier.
III. SITE DESCRIPTION
The Mahanadi is a major river in East
Central India. It drains an area of around 141,600
square kilometres (54,700 sq mi) and has a total
course of 858 kilometres (533 mi) Mahanadi is also
known for the Hirakud Dam.[1] The river flows
through the states of Chhattisgarh and Odisha.
Mahanadi Bridge, Cuttack is connecting Kiakata
and Boudh. This bridge over river Mahanadi is
felicitating communication between Sambalpur,
Rairakhol, Kadligarh, Bimaharajpur and Subalaya
with Boudh town. It is the second biggest bridge in
Odisha. The work on this bridge was started on
22.04.1998 and completed on 31.12.2002.
Page 63 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
Salient Features of Mahanadi Bridge :
Length of Bridge 1830 Meters & 8.40 Meters
wide
Superstructure : Simply supported 45.75
Meters PSC box spans (40 Nos.)
Approach Road & Retaining Wall : 2100
Meters Surajgarh side & 1420 Meters
Nadigaon side.
Foundation - Pile Foundations (1200 mm dia)-
Piers 39 Piers x 4 nos x 16 M (Avg.) = 2496
Meters, - Abutments 2 nos x 9 x 20 M (Avg.) =
360 Meters, Total = 2856 Meters.
Expansion Joint - Strip Seal type (345 Rmtrs.).
Various minor structures were also executed
on approach Roads.
IV. FIELD DATA MEASUREMENTS
The field work are bed material sampling and the
collected geometric data for the bridge. The bed
material sampling was done by taking three
samples from the bed material of the section near
piers, at the location of 0.25, 0.5 and 0.75. The
width of the river in the cross section in order to
conduct the grain size analysis. These samples
finally mixed well to reduce the error of
measurement and get a homogenous sample.
Page 64 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
The cross section data are obtained from
Bhubaneswar Water Resources Directorate
(BWRD).
V. SCOUR MONITORING USING DEPTH-
MEASURING INSTRUMENTATION
Given the importance of the scour problem, a range
of instrumentation has been developed to monitor
scour hole development. These instruments can be
broadly categorized as follows: single use devices,
pulse or radar devices, buried or driven rod
systems, sound-wave devices, fiber-Bragg grating
devices and electrical conductivity devices. They
are described separately in the following sub-
sections.
5.1 Single-use devices :
Single-use devices consist of float-out devices and
tethered buried switches (NCHRP, 2009; Briaud et
al., 2011) that can detect scour at their locations of
installation. These devices are installed vertically in
the riverbed, near a pier or abutment of scour of
interest, and work on the principle that when the
depth of scour reaches the installation depth of the
device, they simply float out of the soil. Although
these are very simple mechanical devices, they have
a number of distinct disadvantages. They require
expensive installation, and have only a single use
before they must be re-installed and can only
indicate that the scour depth has reached the
position of the device. As a result, they give no
Page 65 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
further information on the maximum scour depth
reached. Tethered buried switches must also be
directly hard-wired to a data acquisition system and
as such are susceptible to debris damage. Float out
devices have a finite amount of stored power,
which means they have to be replaced eventually as
part of normal maintenance procedures.
5.2 Pulse or radar devices
Pulse or radar devices utilize radar signals or
electromagnetic pulses to determine changes in the
material properties that occur when a signal is
propagated through a changing physical medium
(Forde et al., 1999). This typically occurs at a water
sediment interface and thus this type of device can
detect a depth of scour at a particular location.
Time-domain reflectometry (TDR) is a method that
uses changes in the dielectric permittivity constants
between materials to determine a depth of scour at a
particular location (Yu and Yu, 2009). This method
was originally developed by electrical engineers
who were interested in detecting discontinuities
along power and communication lines (Yankielun
and Zabilansky, 1999).
5.3 Fiber-Bragg grating
Fiber-Bragg grating sensors are a form of piezo-
electric device (Sohn et al., 2004). These types of
sensors operate based on the concept of measuring
strain along embedded cantilever rods to generate
electrical signals, which can indicate the
progression of scour along the rod. It has been
found that the shift of the Bragg wavelength has a
linear relationship with the applied strain in the
axial direction (Lin et al., 2006). An embedded rod
that becomes partially exposed due to scour will be
subjected to hydrodynamic forces from the flow of
water that induce bending in the exposed rod. This
bending allows the strain sensors to detect that the
rod is free. If a number of strain gauges are
positioned along the rod, the progression of scour
may be monitored. These devices perform
particularly well in monitoring the change in scour
depth with time at their installed location and are
relatively cheap to fabricate.
5.4 Driven or buried rod devices
Buried or driven rod systems include such systems
as the magnetic sliding collar, the “Scubamouse”,
the Wallingford “Tell- Tail” device and mercury tip
switches. These instruments work on the principle
of a manual or automated gravity-based physical
probe that rests on the streambed and moves
downward as scour develops. The gravity sensor is
usually positioned around a buried or driven rod
system in the streambed. It must be sufficiently
large to prevent penetrating into the streambed
while in a static state. A remote sensing element is
typically used to detect the change in depth of the
gravity sensor. This device provides a relatively
straightforward method to monitor scour depth
progression; however, there are a number of
disadvantages.
Page 66 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
5.5 Sound wave devices
A number of devices have been developed that use
sound waves to monitor the progression of scour
holes. They work on the same principle as devices
that use electromagnetic waves, in that waves are
reflected from materials of different densities thus
establishing the location of the watere sediment
interface. This device typically employs a coupled
acoustic source transducer and receiver transducer
that are placed immediately below the water
surface. As the system is towed manually across the
water surface, the source transducer produces short
period pulsed acoustic signals at regular time or
distance intervals. The high frequency seismic
pulse propagates through the water column and into
the subterranean sediments below. This device can
build up profiles of the streambed as some of the
acoustic energy is reflected back to the receiver
when the water sediment interface is encountered.
By combining the signals from multiple locations
and using estimated seismic interval velocities, the
time depth profile can be converted into a depth
profile. Some disadvantages of the system include:
(1) noise with variable streambeds leads to the
crossing-over of signals, (2) both the source and
receiver need to be submerged, meaning that data
cannot be obtained continuously over sand bars,
and (3) the device also requires significant manual
input, which may make it unsuitable as a viable
monitoring regime in a lot of cases. If used
correctly, however, it can provide a very accurate
map of the channel sub-features. Echo sounders
work in a very similar manner to reflection seismic
profilers and can be used to determine scour hole
depths (Anderson et al., 2007). The only major
difference is that they emit higher frequency
acoustic source pulses and due to the rapid
attenuation of the high frequency pulsed acoustic
energy, relatively little signal is transmitted or
reflected within the sub-bottom sediment.
VI. EXPERIMENTAL SET-UP
A series of experiments was conducted at round
nosed rectangular bridge piers models with and
without collar plate skirted around the pier in
uniform cohesionless sediment in steady stated
uniform flow clear water conditions at flow
intensity of 0.95.
Experiments were conducted in a glass sided
rectangular re-circulating tilting flume, 11.0 m
long, 0.756 m wide and 0.55 m deep. Water was
supplied to the flume from an overhead tank, which
got its supply from the laboratory water supply
system. The scour depth at the piers was measured
with a 3 mm diameter point gauge mounted on the
mobile carriage that traversed the flume. The scour
depths could be measured to within 0.1 mm using
point gauge.
At the end of each experiment the water supply to
the flume was gradually stopped and the water was
drained off the flume with extreme care so that the
scour hole and scour patterns developed by the flow
around the model piers, were not disturbed.
Page 67 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
The sediment and mean flow parameters used in
this investigation are listed in table 1.
Since in present study clear-water experiments were
conducted using uniform coarse sediment of 0.95
mm median diameter, duration of 6 hours was
considered adequate. In the case of experiments
with collar, test duration was more.
The mean flow parameters used in this
investigation
Properties of sediment used
Depth of flow, Y0 (m) = 0.14
d84.1 (mm) = 1.03
Mean velocity, U0 (m/s) = 0.391 d15.9 (mm) = 0.73
Threshold velocity, Uc (m/s) = 0.4127 Median Size, d50 (mm) = 0.95
Critical shear velocity, U*c (m/s) = 0.029 Geometric Mean Size, dg (mm) = 0.867
Froude Number, Fr = 0.3328 Geometric Standard, G (mm) = 1.187
Average energy slope, S0 = 0.001 Specific Gravity, Ss = 2.65
Fall Velocity of Sediment, W0 (m/s) = 0.1
Shape Factor, Ψ = 1
Angle of Repose, = 32o
Table 1: The mean flow parameters and Properties of sediment used in present study.
Page 68 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
The dimensions of pier and collar are shown in
Fig.3.
Figure 3: Round nosed rectangular pier without and with collar at 0o angle of attack respectively.
6.1 Collection of Data and Analysis
Detailed measurements of the scoured area around
the model piers were made with the help of point
gauge and finally photographs were taken as shown
in Fig 6. . .
6.2 Experimental data
The data on scour depth variation along and across
the flow direction at round nose rectangular pier
with and without collars were collected from the
experiments. The observed scour profiles along
flow direction at 0° and 15° angles of attack are
shown in figure 4 and Fig.5 respectively. Similar
profiles were drawn for other cases considered in
present study.
Figure 4: Experimental data observed at round nosed rectangular pier without and with collar at 0o angle of attack.
Page 69 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
Figure 5: Experimental data observed at round nosed rectangular pier without and with collar at 0o angle of attack.
Figure 6: Photographs showing placement of collars around pier and scour pattern formed after the
experiment.
Page 70 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
VII. RESULTS AND ANALYSIS
The analysis of results obtained from present
experimental study was made for the following
cases:
Round nosed rectangular pier without collar.
Round nosed rectangular pier with one collar.
Round nosed rectangular pier with two collars
The percent reduction in scour depth, length of
scour hole and width of scour hole at round nose
rectangular pier with and without collar at 0°and
15° angles of attack are shown in table 2.
Table 2: Maximum Scour Depth, Length of scour
hole and width of Scour hole observed at round
nose rectangular pier without and with collar.
Observed Maximum Scour Depth at round nose
rectangular pier without and with collar (cm)
Angle of Attack Without Collar With one Collar
0° 7.9 0.0
15° 9.1 6.65
Angle of Attack Without Collar With two Collars
0° 7.9 0.0
15° 9.1 2.75
Observed Length of Scour Hole at round nose
rectangular pier without and with collar (cm)
Angle of Attack Without Collar With one Collar
0° 60 0.0
15° 60 65
Angle of Attack Without Collar With two Collars
0° 60 0.0
15° 60 19
Table Observed Width of Scour Hole at round
nose rectangular pier without and with collar
(cm)
Angle of Attack Without Collar With one Collar
0° 25 0.0
15° 30 22.5
Angle of Attack Without Collar With two Collars
0° 25 0.0
15° 30 8.0
Page 71 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
VIII. CONCLUSIONS
The reduction in scour depth, length of scour
hole and width of scour hole with one collar
and two collars with respect to the pier without
collar at 0° angle is found to be 100.0 %.
Scour reduction at the pier with one collar at
15° angle of attack is observed as 26.92 %.
Scour reduction at the pier with two collars at
15° angle of attack is observed as 69.78 %.
As compared to pier without collar, the length
of scour hole with one collar at 15° angle of
attack increases by 7.69% while the width of
scour hole at 15° angle of attack reduces by
25%.
As compared to pier without collar, the length
of scour hole with one collar at 15° angle of
attack reduces by 68.33% and the width of
scour hole at 15° angle of attack reduces by
73.33%.
REFERENCES
[1] Brice, J. C., Bloggett, J.C. and others
(1978).” Countermeasures for Hydraulic
Problems at Bridge piers”, Vol. 1 and
2,FHWA-78-162 & 163, Federal Highway
Administration, U.S. Department of
transportation, Washington, D.C.
[2] Breusers, N.H.C. and Raudkivi,
A.J.(1991).“Scouring”, 2nd Hydraulic
Structures Design Manual, IAHR, A.A.
BALKEMA/ROTTERDAM, The
Netherlands.
[3] Chiew Y.M. (1984),’ local scour at bridge
piers,’ Rep. No. 335, School of Engrg.,
Univ. of Auckland, Auckland, New
Zeeland.
[4] Chiew Y.M. (1995),’ Mechanics of riprap
failure at bridge piers’, j. of Hydraulic
Engineering, ASCE, vol. 121,No. 9, pp.
635-643.
[5] Chiew, Y.M. and Melville, B.W. (1987),
‘Local Scour at bridge piers,’ J. Hydr. Res.,
25(1),15-26.
[6] Chiew, Y.M.(1992), Scour Protection at
Bridge Piers”, J. Hydr. Engrg., ASCE,
118(9), 1260-1269.
[7] Chiew Y.M. and Lim, F. H. (2000), ‘Failure
Behavior of riprap layer at bridge piers
under live-bed conditions,” J. Hydr. Engrg.,
ASCE, 126(1),43-55.
[8] Croad, R.N. (1993), ‘ bridge pier scour
protection using riprap,’ central laboratories
report no. PR3-0071, works consultancy
services, N.Z.
[9] Maynord, S.T. (1995),’ Gabion mattress
channel protection design’, J. of Hydraulic
Engineering, ASCE, vol. 121, No. 7, pp.
519-522.
[10] Graf, W.H. and ISTIARTO, (2002), ’Flow
pattern in the scour hole around a cylinder’,
Page 72 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
journal of hydraulic research, vol. 40, No v.
1, pp. 13-20.
[11] Ettema, R., Mostafa, E.A., Melville, B.W.
and Yassin, A.A.(1998),”Local Scour at
Skewed Piers,“ J. Hydr. Engrg.,ASCE,
124(7), 756-759.
[12] Kumar, V, Ranga Raju, K.G. and Vittal,
N.(1999).”Reduction of Local Scour around
Bridge Piers Using Slot and Collar”,
Technical Note, J. Hydr. Engrg., ASCE,
125(12), 1302-1305.
[13] Lagasse, P.F., Thompson, P.L. and Sabol.,
S.A. (1995).”Guarding Against Scour”,
Civil Engrg. ASCE, June.
[14] Lim, F.H. and Chiew, Y.M. (1997),’ Failure
behavior of riprap layer around bridge
piers,’ proc., 27th conf. of IAHR, Managing
water, coping with scaracity and abundance,
184-189.
[15] Melville, B.W. and Raudkivi, A.J.(1997).”
Flow characteristics in Local Scour at
Bridge Piers”, J. Hydr. Research IAHR, 15,
373-380.
[16] Parola, A.C.(1993),”Stability of riprap at
bridge piers”, J. Hydr. Engrg. ASCE, 119,
1080-1093.
[17] Posey, C.J. (1974),’tests of scour protection
for bridge piers,’ J. Hydr. Engrg., ASCE,
100(12),1773-1783.
[18] Richardson, E.V., Harrison, L.J., and Davis,
S.R.(1993).’ Evaluating scour at bridge
piers.’ Rep. No. FHWA-IP-90-017 HEC 18,
Federal highway Administration,
Washington, DC.
[19] Raudkivi, A.J. (1991).”Loose Boundary
Hydraulics, 3rd Edition, Pergamon Pess.
[20] Raudkivi, A.J. (1991).’ Scour at bridge
piers.’ In Scouring, Ed. H. Breusers and A.J.
Raudkivi, A.A. Balkema, Rotterdam. NL.
[21] Raudkivi, A.J. and Ettema, R.(1997).”
Effect of Sediment gradation on Clear
Water Scour”, J. Hydr. Div ASCE,
103(HY10), 1209-1213.
[22] Raudkivi, A.J. and Ettema, R.(1983).” Clear
Water Scour around Cylindrical Piers”, J.
Hydr. Engrg. ASCE, 109(3), 338-350.
[23] Worman, A. (1989),” Riprap Protection
Without Filter Layers”, ”, J. Hydr. Engrg.
ASCE, 115(12), 1615-1629.
[24] Yoon, T.H., Yoon, S.B. and Yoon, K.S.
(1995).” Design of riprap for Scour
Protection around Bridge Piers”, 26th IAHR
Congress, U.K., Vol. 1., pp. 105- 110.
[25] Lim F.H.and Chiew, Y.M.(1996),stability of
riprap layer under live-bed conditions’ proc.,
Ist Inter. Conf. On new/emerging concepts
for rivers, RiverTech’96, Vol.2, 830-837.
[26] Lim, F.H. and Chiew, Y.M. (1997),’ Failure
behavior of riprap layer around bridge
piers,’ proc., 27th conf. of IAHR, Managing
water, coping with scaracity and abundance,
184-189.
Page 73 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
[27] Lim, F.H. (1998),’Riprap protection and its
failure mechanisms’, Athesis submitted to
the School of civil and structural
enginerring, nanyang technological
university,sigapore in fulfillment of the
requirements for the degree of doctor of
philosophy.
[28] Johnson, P.A. and Dock, D.A. (1996). “
Prababilistic Bridge Scour Estimates”, J.
Hydr. Engrg., ASCE, 124(7), 750-754.
[29] Koopaei, K.B. and E.M. Valentine, 2003.
Bridge pier sdcour in self formed laboratory
channels. technical report, university of
Glasgow, Glasgow, U.K.
[30] Research Design Standards Organization,
Lucknow (1972), Scour around piers,
Bridges and Floods Report No. RBF-10.
[31] Ahmed, F., and Rajaratnam N. (1998). ‘
Flow around bridge Piers’, Am. Soc. Civ.
Engrg., J. Hydr. Engrg., 124(3),288-300.
[32] Brice, J. C., Bloggett, J.C. and others
(1978).” Countermeasures for Hydraulic
Problems at Bridge piers”, Vol. 1 and
2,FHWA-78-162 & 163, Federal Highway
Administration, U.S. Department of
transportation, Washington, D.C.
[33] Breusers, N.H.C. and Raudkivi, A.J.(1991).
“Scouring”, 2nd Hydraulic Structures
Design Manual, IAHR, A.A.
BALKEMA/ROTTERDAM, The
Netherlands.
[34] Chiew Y.M. (1984),’ local scour at bridge
piers,’ Rep. No. 335, School of Engrg.,
Univ. of Auckland, Auckland, New
Zeeland.
[35] Chiew Y.M. (1995),’ Mechanics of riprap
failure at bridge piers’, j. of Hydraulic
Engineering, ASCE, vol. 121,No. 9, pp.
635-643.
[36] Chiew, Y.M. and Melville, B.W. (1987),
‘Local Scour at bridge piers,’ J. Hydr. Res.,
25(1),15-26.
[37] Chiew, Y.M.(1992), Scour Protection at
Bridge Piers”, J. Hydr. Engrg., ASCE,
118(9), 1260-1269.
[38] Chiew Y.M. and Lim, F. H. (2000), ‘Failure
Behavior of riprap layer at bridge piers
under live-bed conditions,” J. Hydr. Engrg.,
ASCE, 126(1),43-55.
[39] Croad, R.N. (1993), ‘ bridge pier scour
protection using riprap,’ central laboratories
report no. PR3-0071, works consultancy
services, N.Z.
[40] Maynord, S.T. (1995),’ Gabion mattress
channel protection design’, J. of Hydraulic
Engineering, ASCE, vol. 121, No. 7, pp.
519-522.
[41] Graf, W.H. and ISTIARTO, (2002), ’Flow
pattern in the scour hole around a cylinder’,
journal of hydraulic research, vol. 40, No v .
1, pp. 13-20.
[42] Ettema, R., Mostafa, E.A., Melville, B.W.
and Yassin, A.A.(1998),”Local Scour at
Page 74 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
Skewed Piers,“ J. Hydr. Engrg.,ASCE,
124(7), 756-759.
[43] Kumar, V, Ranga Raju, K.G. and Vittal,
N.(1999).”Reduction of Local Scour around
Bridge Piers Using Slot and Collar”,
Technical Note, J. Hydr. Engrg., ASCE,
125(12), 1302-1305.
[44] Lagasse, P.F., Thompson, P.L. and Sabol.,
S.A. (1995).”Guarding Against Scour”,
Civil Engrg. ASCE, June.
[45] Lim, F.H. and Chiew, Y.M. (1997),’ Failure
behavior of riprap layer around bridge
piers,’ proc., 27th conf. of IAHR, Managing
water, coping with scaracity and abundance,
184-189.
[46] Melville, B.W. and Raudkivi, A.J.(1997).”
Flow characteristics in Local Scour at
Bridge Piers”, J. Hydr. Research IAHR, 15,
373-380.
[47] Parola, A.C.(1993),”Stability of riprap at
bridge piers”, J. Hydr. Engrg. ASCE, 119,
1080-1093.
[48] Posey, C.J. (1974),’tests of scour protection
for bridge piers,’ J. Hydr. Engrg., ASCE,
100(12),1773-1783.
[49] Richardson, E.V., Harrison, L.J., and Davis,
S.R.(1993).’ Evaluating scour at bridge
piers.’ Rep. No. FHWA-IP-90-017 HEC 18,
Federal highway Administration,
Washington, DC.
[50] Raudkivi, A.J. (1991).”Loose Boundary
Hydraulics, 3rd Edition, Pergamon Pess.
[51] Raudkivi, A.J. (1991).’ Scour at bridge
piers.’ In Scouring, Ed. H. Breusers and A.J.
Raudkivi, A.A. Balkema, Rotterdam. NL.
[52] Raudkivi, A.J. and Ettema, R.(1997).”
Effect of Sediment gradation on Clear
Water Scour”, J. Hydr. Div ASCE,
103(HY10), 1209-1213.
[53] Raudkivi, A.J. and Ettema, R.(1983).” Clear
Water Scour around Cylindrical Piers”, J.
Hydr. Engrg. ASCE, 109(3), 338-350.
[54] Worman, A. (1989),” Riprap Protection
Without Filter Layers”, ”, J. Hydr. Engrg.
ASCE, 115(12), 1615-1629.
[55] Yoon, T.H., Yoon, S.B. and Yoon, K.S.
(1995).” Design of riprap for Scour
Protection around Bridge Piers”, 26th IAHR
Congress, U.K., Vol. 1., pp. 105- 110.
[56] Lim F.H.and Chiew, Y.M.(1996),stability of
riprap layer under live-bed conditions’ proc.,
Ist Inter. Conf. On new/emerging concepts
for rivers, RiverTech’96, Vol.2, 830-837.
[57] Lim, F.H. and Chiew, Y.M. (1997),’ Failure
behavior of riprap layer around bridge
piers,’ proc., 27th conf. of IAHR, Managing
water, coping with scaracity and abundance,
184-189.
[58] Lim, F.H. (1998),’Riprap protection and its
failure mechanisms’, Athesis submitted to
the School of civil and structural
enginerring, nanyang technological
Page 75 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
university,sigapore in fulfillment of the
requirements for the degree of doctor of
philosophy.
[59] Johnson, P.A. and Dock, D.A. (1996). “
Prababilistic Bridge Scour Estimates”, J.
Hydr. Engrg., ASCE, 124(7), 750-754.
[60] Koopaei, K.B. and E.M. Valentine, 2003.
Bridge pier sdcour in self formed laboratory
channels. technical report, university of
Glasgow, Glasgow, U.K.
[61] Research Design Standards Organization,
Lucknow (1972), Scour around piers,
Bridges and Floods Report No. RBF-10.
[62] Brice, J.C. and Blodgett, J.C. (1978).
Countermeasures for Hydraulic Problems at
Bridges, Vol. 1 & 2, Federal Highway
Administration, U.S. Department of
Transportation, pp. 10-23.
[63] Chiew, Y.M. (1992). Scour Protection at
Bridge Piers, J. of Hydr. Engrg. ASCE,
118(9), pp.1260-1269.
[64] Chiew, Y.M. (1995). Mechanics of riprap
failure at bridge piers, J. of Hydr. Engrg.
ASCE, 121(9), pp. 635-643.
[65] Chiew, Y.M. and Lim, F.H. (2000). Failure
behavior of riprap layers at bridge piers
under live-bed conditions, Journal of
Hydraulic Engineering, ASCE, 126(1), pp.
43-55.
[66] Croad, R.N. (1993). Brid
[67] ge pier scour protection using riprap,
Central Laboratories Report No. PR3-0071,
Works Consultancy Services, N.Z.
[68] Ettema, R. (1980). Scour at bridge piers,
Rep. No. 216, School of Engrg. University
of Auckland, Auckland, New Zealand.
[69] Gupta, A.K. and Gangadharaiah, T. (1992).
Local scour reduction by a delta wing-lick
passive device, Proc., 8th Congr. of Asia and
Pacific Reg. Div., 2, CWPRS, Pune, India,
pp. B471-B481.
[70] Kumar, V., Ranga Raju, K.G. and Vittal, N.
(1999). Reduction of local scour around
bridge piers using slot and collar, Technical
Note, J. Hydr. Engrg. ASCE, 125(12), pp.
1302-1305.
[71] Lim, F.H. (1998). Riprap protection and its
failure mechanisms, A thesis submitted to the
School of civil and structural engineering,
Nanyang Technological University,
Singapore in fulfillment of the requirements
for the degree of doctor of philosophy.
[72] Lim, F.H. and Chiew, Y.M. (1996).
Stability of riprap layer under live-bed
conditions, Proc., Ist Inter. Conf. On
new/emerging concepts for rivers,
RiverTech’96, Vol.2, pp. 830-837.
[73] Lim, F.H. and Chiew, Y.M. (2001).
Parametric study of riprap failure around
bridge piers, J of Hyd Research, Vol. 30,
No. 1, pp. 61-72.
[74] Lim, S.Y. (1997). Equilibrium clear-water scour
around and abutments, J. of Hydr. Engrg.,
Page 76 of 77
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 13, 2019 (Special Issue) © Research India Publications. http://www.ripublication.com
ASCE, 123(3): 237-243.
[75] Odgaard, A.J. and Wang, Y. (1987). Scour
prevention at bridge piers, Hydr. Engrg. 87,
R.M. Ragan, ed., National Conference,
Virginia, 523-527.
[76] Parola, A.C. (1993). Stability of riprap at
bridge piers, J. of Hydr. Engrg. ASCE, 119,
1080-1093.
[77] Schneible, D.E. (1951). An investigation of
the effect of bridge pier shape on the
relative depth of scour, M.Sc. Thesis,
Graduate College of the State, University of
Iowa, Iowa City, Iowa.
[78] Tanaka, S. and Yano, M.(1967). Local scour
around a circular cylinder, Proc. 12th
Congress I.A.H.R., Ft. Collins, Colorado,
Vol. 3, pp. 193-201.
[79] Thomas, Z. (1967). An Interesting hydraulic
effect occurring at local scour, Proc. 12th
Congress, I.A.H.R., Ft. Collins, Colorado,
Vol. 3, pp. 125-134.
[80] Vittal, N., Kothyari, U.C. and Haghighat,
M. (1994). Clear water scour around bridge
piers group, J. Hydr. Engrg, ASCE, 120(11),
1309-1318.
[81] Worman, A. (1989). Riprap protection
without filter layers, J. Hydr. Engrg., ASCE,
115(12), 1615-1630.
[82] Yoon, T.H., Yoon, S.B. and Yoon, K.S.
(1995). Design of riprap for scour protection
around bridge piers, 26th IAHR Congress,
UK, Vol. 1, pp. 105-110.
[83] Zarrati, A.M., Gholami, H. and Mashahir,
M.B. (2004). Application of collar to
control scouring around rectangular bridge
piers, Journal of Hydraulic Research, IAHR,
42 (1) 97-103.
[84] Zarrati, A.M., Nazariah, M. and Mashahir,
M.B. (2006). Reduction of local scour in the
vicinity of bridge pier group using collars and
riprap, Journal of Hydraulic Engineering,
ASCE,132(2).
Page 77 of 77