Culverts Types, Design,
Installation and Materials
By: Haseeb
Jamal
Definition
An opening through
an embankment for the conveyance of water by means of pipe or an enclosed
channel.
Or.
It is a transverse
and totally enclosed drain under a road or railway.
Types
of Culverts
1.
Pipe
Single or Multiple
2.
Pipe
Arch Single or Multiple
3.
Box
Culvert Single or Multiple
4.
Bridge
Culvert
5.
Arch
Culvert
Pipe culverts are made of smooth steel,
corrugated metal, or concrete material. Their primary purpose is to convey
water under roads, although a variety of wildlife use them as passageways.
Pipe culverts typically range from 1- 6
feet in diameter and are the least expensive type of culvert. Round culverts
are best suited to medium and high stream banks.
Pipe
Arch Single or Multiple
Pipe-arch culverts provide low clearance,
openings suitable for large waterways, and are more aesthetic. They may also
provide a greater hydraulic advantage to fishes at low flows and require less
road fill.
Box
Culvert Single or Multiple
Box culverts are used to transmit water
during brief runoff periods. These are usually used by wildlife because they
remain dry most of the year.
They can have an artificial floor such as
concrete.
Box culverts generally provide more room
for wildlife passage than large pipe culverts. Box culverts are usually made up
of Reinforced Concrete (RCC)
Arch
Culvert
A pipe arch culvert is a round culvert
reshaped to allow a lower profile while maintaining flow characteristics. It is
good for installations with shallow cover.
Materials used for arch culverts are RCC,
Corrugated Metal or Stone Masonry.
Design
of Reinforced Concrete Culverts
Location
Ideally, the axis of a culvert should
coincide with that of the natural streamed and the structure should be straight
and short.
This may require modification of the
culvert alignment and grade.
Often it is more practical to construct the
culvert at right angles to the roadway.
However, the cost of any change in stream
channel location required to accomplish this should be balanced against the
cost of a skewed alignment of the culvert, and changes in channel hydraulics
should be considered.
Grade
and camber
The culvert invert gradient should be the
same as the natural streambed to minimize erosion and silting problems.
Foundation settlement should be countered
by cambering the culvert to ensure positive drainage.
Entrance
and outlet conditions
It is often necessary to enlarge the
natural channel a considerable distance downstream of the culvert to prevent
backwater from entering the culvert.
Also, enlargement of the culvert entrance
may be required to prevent pending above the culvert entrance.
The entrance and outlet conditions of the
culvert structure directly impact its hydraulic capacity.
Rounding or beveling the entrance corners
increases the hydraulic capacity, especially for short culverts of small cross
section.
Scour problems can occur when abrupt
changes are made to the streamed flow line at the entrance or outlet of the
culvert.
Materials
used
Foundation
material
Materials to be used for the culvert pipe
foundation should be indicated on the drawings. Refer to the geotechnical
foundation report for the project.
Bedding materials
Bedding class and materials for culverts
should be indicated on the drawings.
When designing the bedding for a box
culvert, assume the bedding material to be slightly yielding, and that a
uniform support pressure develops under the box section.
Purpose
and Use
Culverts are used in roads, bridges, and
berm construction to prevent flooding and washing out of roads.
They also minimize erosion, build-up of standing water, and provide pathways for run-off.
Haseeb Jamal
I
am a Civil Engineer, graduated from University of Engineering and Technology,
Peshawar, Pakistan in 2010. I also have a PG-Diploma in Disaster Management and
MS in Urban Infrastructure Engineering (In Progress). My expertise include
civil related softwares like AutoCAD, SAP2000, MS Project, Primavera, MS Office
and GIS. My technical skills include project management, monitoring and
evaluation, structural assessment, disaster risk management, Quantity survey,
land survey, material testing, site management and technical writing. I am
trained in writing project progress reports as well as proposals and concept
papers. I have also received advanced training on surveying, proposal writing,
Monitoring and Evaluation of projects as well as organizations.
I
have worked as Project Engineer at National Research and Development
Foundation, Peshawar and CENCON Associates. I also worked with Spectra
Engineering Solutions as Senior Civil Engineer in monitoring of World Bank and
UNDP funded projects all over Khyber Pakhtunkhwa and FATA. Currently, I am
working as Deputy Manager Development at NayaTel, Peshawar.
https://www.aboutcivil.org/culvert-definition-types-culvert-materials.html
https://www.aboutcivil.org/culvert-definition-types-culvert-materials.html
https://www.google.com/search?sxsrf=ALeKk03W7p6VwprOX45yhXm2WQ4ha48l5g:1609573853878&source=univ&tbm=isch&q=Culverts+Types+images&sa=X&ved=2ahUKEwjd8LLu4fztAhWU-mEKHUV5C6AQjJkEegQIAxAB&biw=1517&bih=724
No comments:
Post a Comment