(AUTONOMOUS)
B. Tech VII Semester Supplementary Examinations, May 2018
(Regulations: VCE-R11/R11A)
PAVEMENT ANALYSIS AND DESIGN
(Civil Engineering)
Date: 28 May, 2018 AN Time: 3 hours Max Marks: 75
Answer ONE question from each Unit
All Questions Carry Equal Marks
Unit I
1. Explain how the subgrade soil and climatic factors affect the design of flexible pavement
design.
10M
Explain in step by step procedure the determination of Equivalent Wheel Load Factors.
5M
2. With a neat diagram explain the composition and functions of each layers of a
bituminous pavement system.
5M
With a neat diagram analyze the variation in vertical stress, with depth, in a single layer
for a flexible pavement. A circular load of radius 15cm with uniform contact pressure of
7kg/cm2 is applied on the surface of a homogeneous elastic mass. Determine the vertical
stress under the center of the load at a depth of 45cm from the surface using both the
vertical stress distribution chart and formula.
10M
Unit II
3. State the assumptions made by Westergaard in analysis of stresses in rigid pavement. 5M
A cement concrete pavement slab of thickness 20cm is constructed over a granular subbase
having modulus of reaction 15kg/cm3 .The maximum temperature difference
between the top and bottom of the slab during summer day and night is found to be
180C. The spacing between the transverse contraction joint is 4.5m and that between
longitudinal joints is 3.5 m. The design wheel load is 5100kg, radius of contact area is
15cm, modulus of CC is 3x105kg/cm2, Poisson's ratio is 0.15 and coefficient expansion of
CC is 10x10-6 per oC and friction coefficient is 1.5. Calculate warping stresses at interior,
edge and corner.
Fig.1
10M
4. With a neat sketch explain warping stresses developed in Concrete pavement. 7M
Explain in detail how critical stresses are calculated in concrete pavement.
8M
Unit III
5. With a neat sketch explain Expansion joint. 7M
Explain Cement-soil stabilization. 8M
Cont…2
2
6. Draw a neat sketch showing the layout of all the types of joints that occur in Cement
Concrete pavements and write down the reason for providing the following types of
joints:
i. Expansion joints
ii. Contraction joints
7M
Design a flexible pavement using IRC 37:2001 from the following data:
Subgrade CBR
No. of commercial vehicles per day at the latest count 2660
Lane distribution factor 0.75, Annual rate of traffic growth
Design life 10 years
Time from last traffic count to the end of construction 2 years.
Axle Load (Tonnes) of total vehicles
20 1.1
16 7.5
12 24
10 28
8 39.4
8M
Unit IV
7. Explain the importance of conducting stripping test on road aggregates. Indicate the
advantages and limitations of this test.
10M
Mention the desirable properties of bituminous mix for pavement surface course.
5M
8. Brief out the construction procedure of water bound macadam base and any
rectifications of defects that can be carried out.
10M
Brief out the step by step procedure of carrying out ductility test on bituminous
specimen.
5M
Unit V
9. Explain the different types of failures in rigid pavement. 10M
With a neat sketch explain rutting.
5M
10. Explain Benkelman beam method with neat sketch. 10M
List atleast 5 different types distress in rigid pavement and explain one in detail. 5M