CE3010: CE30 10: Transpo ransportatio rtation n Engin Engineerin eering gI Atul Narayan, S. P. IIT Madras
August 13, 2015
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Class timings
Classes will be in the A slots on Monday, Thursday and Friday
Additional classes on Tuesday A slot if required.
Please keep yourself available for all the A slots of the semester. Do not commit yourself to any activity on A slots.
Contact Information
My office is at 238H.
You can contact me at
[email protected] or
[email protected]
For any questions or discussion, just stop by my office. We will fix an appointment if we cannot meet then. Your contact information?
Course contents and schedule
Course contents and schedule will be mailed to you.
Reference Textbooks for course
Chakroborthy and A. Das, Principles of Transportation Engineering, Prentice-Hall of India, 2003. C. S. Papacostas and P. D. Prevedouros, Transportation Engineering and Planning, Third Edition, Prentice Hall, 2001. Khanna and Justo Highway Engineering, Ninth Edition, Nemchand, 2011 J. H. Banks, Introduction to Transportation Engineering, Mc-Graw Hill Book Company, 2002. P. H. Wright and K. K. Dixon, Highway Engineering, John Wiley & Sons, Seventh Edition, 2004. C. J. Khisty and B. K. Lall, Transportation Engineering An Introduction, Prentice- Hall of India, 2002. Yang Huang, Pavement Analysis and Design, Pearson, 2004. Yoder, E.J., and Witczak, Principles of Pavement Design, 2nd ed. John Wiley and Sons, 1975. R. Horonjeff and F. X. McKelvy, Planning and Design of Airports, Mc-Graw Hill International Editions, 1993.
References for Pavement Design and Analsysis section
Textbook Yang H. Huang (2004). Pavement Analysis and Design, Pearson. Additional References Yoder and Witczak (1975), Principles of Pavement Design, John Wiley and Sons. IRC 37 (2012) and IRC 58 (2002)
Grading Policy
Assignments: Mid-Semester Examination: End-Semester Examination:
20% 30% 50%
Assignments
Students can work on assignments in groups of maximum two.
One submission per group is enough.
Due dates are as listed in the calendar.
Classroom Policy
Any form of misconduct including cheating, plagiarism, fabrication, etc. will not be tolerated. Any student caught doing so will be assured maximum punishment.
If the submission of two or more groups have the same content with same mistakes, both groups will be given zeros for that problem.
Attendance rules of IIT Madras will be strictly followed .
Please turn off all cell phones before coming to class.
Please be courteous to fellow students. Do not disrupt the class by talking, using your cell phone, etc.
Note-taking
Attend all classes and write down notes whenever it appears important. Reading materials will be sent to you once the lecture topic is finished. Please use the reference textbooks for background reading.
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Primary learning objectives
To design flexible and rigid pavements using the Indian Roads Congress design methods To evaluate when it would be necessary to modify the design methods
Design Process
Source:MEPDG Flexible Pavement Design Guide
Subordinate learning objectives
To analyze the stress-strain distribution in pavements for given loading conditions. To estimate pavement distresses based on stresses and strains in pavement structure. To explain the effect of mechanical properties on pavement behavior and performance. To analyze the stresses and distresses caused by vehicle loading. To estimate the expected volume of traffic in design life
Levels of learning
Remembering : Describing, identifying
Understanding: Interpreting, explaining
Applying: Executing, Implementing
Analyzing: Comparing, Deconstructing
Evaluating: Expringmenting, Judging
Creating: Desiging, Constructing
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Aggregates
Aggregates are granular materials such as river gravel, crushed stone or sand. It is the longest english word you can type with the left hand (standard typing procedure)
(a) Sand
(b) River Gravel
(c) Granite
Bitumen
Bitumen is a processed form of the residue obtained in fractional distillation of petroleum. It is also known as asphalt or asphalt cement.
Bituminous concrete
Bituminous concrete is the compacted mixture of bitumen and aggregates. It is also known as bituminous mixture, asphalt concrete, asphalt mixture and hot-mix asphalt (HMA).
(a) Loose Mix
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Typical Pavement Structure Seal Coat Surface Course Binder Course
Base Course
Sub-base Course
Subgrade
Tack Coat Prime Coat
Seal Coat
It is a thin layer of bitumen with or without crushed aggregates embedded in it.
It is also known as chip seal or bituminous surface treatment.
It is mainly useful in colder climates.32
It is used for: Waterproofing the surface Improving skid resistance Improving surface finish and sealing surface cracks
Surface Course
It is the top-most layer in an asphalt concrete pavement.
The layer is usually made with dense-graded HMA.
Open graded HMA with adequate porosity may also be used.
It is also known as wearing course.
Purpose: To provide resistance to frictional stresses caused by moving vehicles To provide skid resistance To waterproof the pavement structure
It is meant to wear with repetitions of vehicle loading.
It can be periodically rehabilitated during the design period.
Binder Course
It is the layer below the surface course. Purpose: To distribute the stresses due to vehicle loading over a large area To reduce the stresses and strains in the underlying layers To reduce the cost of the pavement
The binder course consists of HMA with larger aggregates and smaller binder content.
Tack Coat and Prime Coat
Both prime coat and tack coat are thin layers of bitumen. Hot bitumen, bituminous emulsion or cut-back asphalt is sprayed on the surface for the coats. Their purpose is to ensure bond between pavement layers. Difference between tack coat and prime coat Since tack coat is between two HMA layers, it need not penetrate either layers. Prime coat should penetrate the underlying layer to be effective
Base and Sub-base Course
Additional layers over the subgrade to reduce stresses on the subgrade Both layers are similar. The subbase is usually constructed using cheap and poorer quality material compared to the base layer. Types of base layers: Untreated aggregate base Asphalt treated base Reclaimed asphalt pavement Chemically treated base (with cement, lime, etc.) Crushed slag
Subgrade
Natural geological formation in the construction site over which the pavement is constructed. Sometimes the top of the subgrade is prepared through compaction.
Outline
First-day information Introduction to Pavement Design Introduction to Flexible Pavement Materials Introduction to Flexible Pavement Structure Distresses of Flexible Pavements
Types of Distresses of Flexible Pavements
Alligator cracking
Longitudinal and transverse Cracking,
Rutting
Bleeding
Joint reflection cracking
Alligator Cracking
It is caused by fatigue
“Bottom-up” mechanism of crack propogation
Source: PavementInteracti
Longitudinal cracking
Possible causes include “top-down” fatigue and joint location
Source: PavementInteractive.org
Transverse cracking
Caused by contraction of bituminous layers at low temperatures
Rutting
Permanent deformation along wheel path
Rutting may be accompanied by swelling
Source: PavementInteractive.org
Bleeding
Bleeding is bitumen being squeezed out of the mixture
Caused by poor mix design - lack of air voids
Source: PavementInteractive.org
