Menu

International Dubal 2 1 PG student, Department

0 Comment

 International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 10 | Oct -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 30
A STUDY OF BEHAVIOR OF RCC BOX CULVERT UNDER THE INFLUENCE
OF STATIC AND DYNAMIC LOADS IN ACCORDANCE WITH IRC
Mahesh D. Kakade1, Rajkuwar A. Dubal 2
1 PG student, Department of civil (structural) engineering, JSPM’s RSCOE, Tathawade, Pune, Maharashtra, India
2 Associate professor, Department of civil (structural) engineering, JSPM’s RSCOE, Tathawade, Pune,
Maharashtra, India
———————————————————————***———————————————————————
Abstract – Box culvert problem is a complicated example of
soil structure interaction where the relative stiffness between
the backfill soil and the culvert materials is critical factor in
the load carrying capacity of culverts. Culvert is provided
under earth embankment for crossing of water course like
streams. across the embankment, as road embankment cannot
be allowed to obstruct the natural water way This project
deals with study of some of the design parameters of box
culverts like effect of earth pressure and depth of cushion
provided on top slab of box culverts and the relative study of
box full and box empty conditions is done using finite element
analysis tool ANSYS. The finite element model of ANSYS can be
compared with numerical models as a plain strain problem.
Furthermore box culvert with cushion or without cushion is
also compared for different cases.
Key Words: Box culvert, FEA, Ansys, IRC.
1. INTRODUCTION
Box Culverts consists of two Horizontal and two vertical slabs
built monolithically which are ideally suited for a road or
railway bridge crossing with high embankments crossing a
stream with a limited flow. If the discharge in a drain or
channel crossing a road is small, and if the bearing capacity of
the soil is low, then the box culvert is an ideal bridge
structure. The height of the vent generally doesn’t exceed 3
meters. Box culverts are economical due to their rigidity and
monolithic action and separate foundation are not required
because the bottom slab is resting directly on the soil, serves
as raft. For a box culvert, the top slab requires to withstand
the dead loads, live loads from moving traffic, earth pressure
on sidewalls, water pressure from inside, and pressure on the
bottom slab besides self weight of the slab. The structure is
designed like a rigid frame using moment distribution
method to obtain final distributed moments on the basis of
the relative stiffness of the slab and vertical walls. A few
things like depth of cushion, coefficient of earth pressure for
lateral pressure on walls, width or angle of dispersion for live
loads on box without cushion and with cushion for structural
deformation are important items where opinion of the
designers vary and therefore need to be studied in much
detail. These affect the design significantly and therefore,
required to be assessed correctly for designing a safe
structure. Therefore an attempt is made to study with
cushion and without cushion for static and moving live load
in box full and box empty conditions.
What is a Culvert?
Culvert is a tunnel structure constructed under roadways
or railways to provide cross drainage or to take electrical or
other cables from one side to other. The culvert system is
totally enclosed by soil or ground.
Materials for Culvert Construction
Culverts are like pipes but very large in size. They are made of
many materials like
I. Concrete
II. Steel
III. Plastic
IV. Aluminum
V. high density polyethylene
In most cases concrete culverts are preferred. Concrete
culverts may be reinforced or non-reinforced. In some cases
culverts are constructed in site called cast in situ culverts.
Precast culverts are also available. By the combination above
materials we can also get composite culvert types.
Types of Culverts
Following are the types of culverts generally used in
construction:
Pipe culvert (single or multiple)
Pipe Arch (single or multiple)
Box culvert (single or multiple)
Arch culvert
Bridge culvert
Pipe Culvert (Single or Multiple)
Pipe culverts are widely used culverts and rounded in
shape. The culverts may be of single in number or multiple. If
single pipe culvert is to be used then larger diameter culvert
is installed. If the width of channel is greater, then we will go
for multiple pipe culvert system. They are suitable for larger
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 10 | Oct -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 31
flows very well. The diameter of pipe culverts ranges from 1
meter to 6m. These are made of concrete or steel etc.
Pipe Arch Culvert (Single or Multiple)
Pipe arch culverts means nothing but they looks like half
circle shaped culverts. Pipe arch culverts are suitable for
larger water flows but the flow should be stable. Because of
this arch shape fishes or sewage in the channel is easily
carried to the outlet without stucking at the inlet or at the
bottom of channel. This type of culverts can also be provided
in multiple numbers based on the requirement. They also
enhance beautiful appearance.
Box Culvert (Single or Multiple)
Box culverts are in rectangular shape and generally
constructed by concrete. Reinforcement is also provided in
the construction of box culvert. These are used to dispose
rain water. So, these are not useful in the dry period. They can
also be used as passages to cross the rail or roadway during
dry periods for animals etc. Because of sharp corners these
are not suitable for larger velocity. Box culverts can also be
provided in multiple numbers if the width of channel is large.
Arch Culvert
Arch culvert is similar to pipe arch culvert but in this case an
artificial floor is provided below the arch. For narrow
passages it is widely used. The artificial floor is comprised of
concrete and arch is also of concrete. Steel arch culverts are
also available but very expensive so less used.
Bridge Culvert
Bridge culverts are generally provided on canals or
rivers and also used as road bridges for vehicles. For
this culvert a foundation has to be laid under the
ground surface. A series of culverts is laid and
pavement surface is then laid on top this series of
culverts. Mostly these are rectangular shaped culverts
and can replace the box culverts if artificial floor is not
necessary.
2. METHODOLOGY
2.1 Introduction
The finite element method (FEM) is the most popular
simulation method to predict the physical behavior of
systems and structures. Since analytical solutions are in
general not available for most daily problems in engineering
sciences numerical methods like FEM have been evolved to
find a solution for the governing equations of the individual
problem. Much research work has been done in field of
numerical modelling during last thirty years which has
enabled engineers today to perform simulations close to
reality. Nonlinear phenomena in structural mechanics like
nonlinear material behavior, large deformations or contact
problems have become standard modelling tasks. Due to a
rapid development in the hardware sector resulting in more
powerful processors together with decreasing costs of
memory it is nowadays possible and easy to perform
simulations even for models with millions of degrees of
freedom. In a mathematical sense the finite element solution
always just gives us an approximate numerical solution of the
considered problem. Sometimes it’s not always an easy task
for an engineer to decide whether the obtained solution is a
good or bad one. If experimental or analytical results are
available it is very easily possible to verify any finite element
result. However, to predict any structural behaviour in a
reliable way without experiments every user of a finite
element package must have a certain background about the
finite element method in general. In addition, he should also
have fundamental knowledge of the applied software to be
able to judge the appropriateness of the chosen elements and
algorithms. This paper is has tried to show a summary of
ANSYS capabilities to obtain results of finite element analyses
as accurate as possible.
2.2 Materials properties
The characteristics of the real properties of materials
are presented in Table 3.1 Materials properties of box
culvert were as follows.
Table -1 Material properties
Sr.No. Material Property Value
1
Reinforcing
bar
Yield stress
fsy(MPa) 250
Ultimate
strengthfsu
(MPa)
350
Young’s modulus
Es(MPa) 200 103
Poisson’s ratio µ 0.3
Ultimate tensile
strain et 0.25
2 Concrete
Compressive
strengthfsc(MPa) 42.5
Tensile
strengthfsy(MPa) 3.553
Young’s modulus
Ec(MPa) 32920
Poisson’s ratio µ 0.15
Ultimate
compressive
strain es
0.045
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 10 | Oct -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 32
2.3 Material modeling

The definition of the proposed numerical model was
made by using finite elements available in the ANSYS code
default library. SOLID186 is a higher order 3-D 20-node solid
element which represents quadratic displacement behavior.
This element is defined by 20 nodes which have three
degrees of freedom per node: translations in the nodal x, y,
and z directions. The element supports plasticity, hyper
elasticity, creep, stress stiffening, large deflection, and also
large strain capabilities. It also has mixed formulation
capability to simulate deformations of nearly incompressible
elastoplastic materials, and fully incompressible hyper elastic
materials. The geometrical representation of has been shown
in SOLID186 fig 2.5.
This SOLID186 3-D 20-node homogenous/layered
structural solid were adopted to discretize the concrete slab,
which are also able to simulate cracking behavior of the
concrete under tension (in three orthogonal directions) and
crushing in compression, to evaluate the material nonlinearity
and also to enable the inclusion of reinforcement
(reinforcement bars scattered in the concrete region).The
element SHELL43 is defined by four nodes which have six
degrees of freedom at each node. The deformation shapes are
linear in both in-plane directions. The element allows for
plasticity, creep, stress stiffening, large deflections, and large
strain capabilities. The representation of the steel section has
been made by the SHELL 43 elements, which allow the
consideration of non-linearity of the material and show linear
deformation on the plane in which it is present. CONTA174 is
used to exhibit contact and sliding between 3-D “target”
surfaces (TARGE170) and a deformable surface which is
defined by this element. The element is applicable to 3-D
structural and coupled field contact analyses. The geometrical
representation of CONTA174 is show in fig 2.2. Contact pairs
couple general axisymmetric elements with standard 3-D
elements. A node-to-surface contact element represents
contact between two surfaces by specifying one surface as a
group of nodes. The geometrical representation of is show in
TARGET 170 fig 2.3.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

The TARGET 170 and C0NTA 174 elements were used
to represent the contact slab-beam interface. These
elements are able to simulate the existence of pressure
between them when there is contact, and separation
between them when there is not. The two material
contacts also take into account friction and cohesion
between the parties.
Fig.no.2.2 CONTA 174
Fig.no.2.3 TARGET 170
Fig.no.2.4 Shell 43
Fig.no.2.5 Beam 189
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 10 | Oct -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 33
Fig. 2.6 Solid 186
2.4. Failure criterion
Two limits are established to define the ultimate load for each
finite element investigation: a lower and an upper bound,
corresponding to concrete compressive strains of 0.2%, and
0.35%, respectively. These two limits define an interval in
which the composite beam collapse load is located. A third
limit condition, hereinafter referred to as the stud failure
point, can also be reached when the composite beam’s most
heavily loaded stud reaches its ultimate load, as defined from
the appropriate push-out tests. If the stud failure point is
located before the lower bound of concrete (i.e., the
corresponding load of the stud failure point is smaller than
the lower bound load) then the mode of failure of the
composite beam is considered as stud failure. Conversely, if
the stud failure point is located after the upper bound of
concrete, the mode of failure should be assumed as being
concrete crushing. For the intermediate case, where the stud
failure point lies between the lower and upper bounds of
concrete, than the mode of failure could be either of the two.
Therefore, the proposed finite element model is able to
predict the failure modes associated with either slab crushing
or stud failure.
Fig. no. 2.7 Constitutive relation for the steel of the
reinforcement
Fig. no. 2.8 Constitutive relation for the concrete
3. PROBLEM STATEMENT
Clear span: 3 m
Clear height: 3 m
Top slab thickness: 0.42 m
Bottom slab thickness: 0.42 m
Side wall thickness: 0.42 m
Unit weight of concrete: 24 kN/m3
Unit weight of earth: 18 kN/m3
Unit weight of water: 10 kN/m3
Co-efficient of earth pressure at rest: 0.5
Total cushion on top: 0.0 m
Thickness of wearing coat: 0.065 m
Carriageway 2 lane divided
Concrete grade M25 = 25 Mpa
Steel grade Fe 415 = 415 Mpa
Modular ratio: 10
n (for depth of neutral axis): 0.294
j (for effective depth): 0.902
k (for moment of resistance): 1.105 Mpa
All dimensions are in meter unless mentioned otherwise.
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 10 | Oct -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 34
All moments are in kN-m and shear force in kN unless
mentioned otherwise.
Fig no. 3.1 Cross section of box culvert
4. ANALYSIS OF STRUCTURE
Table -2 Bending moment calculations
Load Case
Maximum distributed moments
at supports
MAB MDC MAD MDA
Total
load
Maximum
of all cases 71.89 30.12 71.89 30.12
Braking
force
Distributed
moments
at support
48.90 48.90 48.90 48.90
Design
moments
Support
moments
including
braking
120.79 79.02 120.79 79.02
5. RESULTS AND DISCUSSION
Comparison of results for box full condition with cushion
and without cushion
Chart -1: Total deformation
Chart -2: Normal stress
Chart -3: Principal stress
Chart -4: Von-misces stress
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 10 | Oct -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 35
Chart -5: Shear stress
6. CONCLUSION
The total deformation for box full without cushion
condition is more than box full with cushion condition.
The normal stress for box full without cushion condition
is more than box full with cushion condition.
The maximum principle stress for box full without
cushion condition is more than box full with cushion
condition.
The equivalent stress for box full without cushion
condition is more than box full with cushion condition.
The shear stress for box full without cushion condition is
less than box full with cushion condition.
7. ACKNOWLEDGEMENT
I express my sincere gratitude and respect to my project
guide Prof. R. A. Dubal and Prof. G. R. Patil, Professor
department of structure (Civil), Rajarshi Shahu college of
Engineering, Pune for their valuable suggestions, timely
support and encouragement. I thank them for numerous
useful suggestions apart from valuable guidance to me.
I would like to convey my sincere gratitude to my friends,
colleagues and all the staff members of department of
structure (Civil) for their support and encouragement. The
meaning of work is incomplete without paying regards to my
respected parents and family whose blessings and continuous
encouragement have shown me the path to achieve my goals.
REFERENCES
? Sarah L. Orton, J. Erik Loehr, Andrew Boeckmann,;
and Garrett Havens, “Live-Load Effect in Reinforced
Concrete Box Culverts under Soil Fill”, American
Society of Civil Engineers, published in 2015
? Neha Kolate, Molly Mathew, Snehal Mali, “Analysis
and Design of RCC Box Culvert”, International
Journal of Scientific & Engineering Research, ISSN
2229-5518, Volume 5, Issue 12, December-2014
? A. C. Lande, S. K. Kamane, S. A. Mahadik, “Finite
Element Analysis of Box Culvert”, 3rd World
Conference on Applied Sciences, Engineering &
Technology 27-29 September 2014
? Komal S. Kattimani, R. Shreedhar, “Parametric
Studies of Box Culverts”, International Journal of
Research in Engineering and Science (IJRES) ISSN
(Online): 2320-9364, ISSN (Print): 2320-9356,
Volume 1 Issue 1, May. 2013
? Anil K. Garg and Ali Abolmaali, “Finite-Element
Modeling and Analysis of Reinforced Concrete Box
Culverts”, Journal of Transportation Engineering,
Vol. 135, No. 3, March 1, 2009
? B.N. Sinha & R.P. Sharma, “Rcc Box Culvert –
Methodology and Designs Including Computer
Method”, Journal of the Indian Roads Congress,
October-December 2009
? E. Awwad, M. Mabsout , S. Sadek , and K. Tarhini,
“Finite Element Analysis of Concrete Box Culverts”,
American Society of Civil Engineers, published in
2000
? Shad M. Sargand, Glenn A. Hazen, “Structural
Evaluation of Box Culverts”, Journal of Structural
Engineering, Vol. 118, No. 12, December, 1992.
ASCE, ISSN 0733-9445/92/0012-3297
? IRC: 5 – 1998
? IRC: 6 – 2000
? IS:456–2000

x

Hi!
I'm Rick!

Would you like to get a custom essay? How about receiving a customized one?

Check it out