1. Indian Institute of Technology Bhubaneswar, India
Evaluation of Stiffness of Cement Stabilized Granular Lateritic Soils using UPV Test
Presented by
Dr. Umesh Chandra Sahoo
Indian Institute of Technology Bhubaneswar, India
4th International Conference on Transport Infrastructures (ICTI)

2. OUTLINE OF PRESENTATION
Introduction
Ultrasonic Pulse Velocity Test
Materials and Methods
Results and Discussions
Conclusions
References

3. Introduction
Ultrasonic Pulse Velocity
Materials and Methods
Results and Discussions
Conclusions
References

4. INTRODUCTION Typical section of flexible pavement Bituminous layer
Base
Sub-base
Subgrade
Granular Base
Granular Sub-Base

5. INTRODUCTION
Huge length of roads are being constructed in India through various development programmes.
Scarcity of good quality natural aggregates in many places has become a hindrance to road construction
Transportation of crushed stones from a larger distance causes:
Waste of energy
Increase in hauling cost
Air pollution

6. Granular Lateritic Soil
INTRODUCTION
It has prompted to explore the availability of marginal aggregates, locally available granular soils and waste materials and to investigate the feasibility of using these materials in the structural layers of pavements.
Usually do not meet the specifications
locally available soils
marginal aggregates
recycled materials
Granular Lateritic Soil

7. Granular Lateritic Soil
INTRODUCTION
Granular Lateritic Soil
Tropical or subtropical residual soil
Rich in iron & aluminium oxide

8. Granular Lateritic Soil
INTRODUCTION
Granular Lateritic Soil
Approximately 3.5% area of India

9. INTRODUCTION
Stabilisation of granular lateritic soil can be employed to make it suitable for subbase and base layer
Bitumious layer
Base
Subbase
Subgrade

10. Flexural modulus for cement bound/ stabilized materials
INTRODUCTION
Recent Approach of Pavement Analysis
Mechanistic Pavement Design
Material Properties
Elastic Modulus
Flexural modulus for cement bound/ stabilized materials

11. INTRODUCTION Flexural Modulus
For an isotropic, homogeneous and elastic material, when the material is flexed i.e., allowed to bend by applying force which is perpendicular to the longitudinal direction of material, the stiffness of the material that resists the bending is known as flexural modulus.
Determined by applying cyclic load on a beam sample in a flexure test arrangement
This test simulates the stress strain gradient observed in stabilized layers of any pavement
However, determination of flexural modulus is a tedious and time consuming

12. Common Tests used for characterization of stabilized materials:
INTRODUCTION
Common Tests used for characterization of stabilized materials:
Unconfined Compressive Strength Test (UCS)
Flexural Strength (FS)
Indirect Tensile Strength (ITS)

13. INTRODUCTION
Non-Destructive Tests which may be used for characterization of stabilized material
Ultrasonic pulse velocity test (UPV test)
Rebound hammer tests
Seismic modulus tests
Very fast and rapid methods

14. INTRODUCTION
Non-Destructive Tests which may be used for characterization of stabilized material
Ultrasonic pulse velocity test (UPV test)
Rebound hammer tests
Seismic modulus tests
Rebound value : A relative measurement of surface hardness

15. INTRODUCTION
Non-Destructive Tests may be used for characterization of stabilized material
Ultrasonic pulse velocity test (UPV test)
Rebound hammer tests
Seismic modulus tests
Ultrasonic pulse travels through the mass media; hence, pulse velocity is a relative measurement the elastic properties of the whole mass rather than any surface properties

16. UPV Test on stabilized materials
INTRODUCTION
UPV Test on stabilized materials
Many researchers have established relationships between pulse velocity and physico- mechanical properties of concrete, but few studies on cement stabilized soils.
The relationships developed by Mandal et al (2016) as given below do not address the flexural modulus of the materials, which is desired for mechanistic pavement design.
UPV test can also be employed for performance study of constructed stabilized pavements as it is a rapid method of determining the in-situ modulus.

17. INTRODUCTION Objective of this study:
Predicting strength and stiffness of cement stabilized granular lateritic soils using UPV test

18. Introduction
Ultrasonic Pulse Velocity
Materials and Methods
Results and Discussions
Conclusions
References

19. ULTRASONIC PULSE VELOCITY
Ultrasonic waves are stress waves with frequency more than 20 kHz in solid media
When a electrodynamic pulse is applied to any material, 3 types of stress waves are generated.
P-wave (Longitudal/Primary wave)
Body wave
Stress waves
S-wave (Shear wave)
R-wave (Raleigh wave)
Surface wave

20. ULTRASONIC PULSE VELOCITY
Due to the transmission of P wave or Primary wave, particles move in the same direction (longitudinal) as the direction of wave propagation.
Transverse waves or S waves result in movement of particles in a direction perpendicular to the direction of wave.
As the P waves are much faster than S-waves, the arrival of P-wave is recorded first and used for determination of velocity.

21. ULTRASONIC PULSE VELOCITY TEST
t is the transmission time
l is the length of transmission of pulse
Different Transmission modes in UPV test l
UPV test arrangement

22. ULTRASONIC PULSE VELOCITY TEST
The strain range of particles in UPV testings are very small i.e, less than <10-6
Propagation of ultrasonic pulse inside a material depends on the materials properties
Important parameters of wave propagation which can be quantified with the material elastic properties in small strain range are velocity and attenuation.
However, out of these two parameters, velocity is related to the elastic and mechanical properties.

23. ULTRASONIC PULSE VELOCITY TEST
UPV Test
Elastic property: Constrained Modulus
Constrained modulus : Stiffness of the material which is a measure of resistance of the particle movement in longitudinal direction due to compression or P wave or longitudinal wave in a mass media either in ultrasonic test or due to seismic wave
Vp is ultrasonic pulse velocity in m/s , t is transmission time in sec and l is transmission distance in meter, ρ is density kg/m3, μ is dynamic Poisson's ratio.

24. Introduction
Ultrasonic Pulse Velocity
Materials and Methods
Results and Discussions
Conclusions
References

25. Detailed Experimental Program
MATERIALS AND METHODS
Characterization of granular lateritic soil
Characterization of cement bound material
Strength and Modulus test
Ultrasonic Pulse Velocity Test
Unconfined Compressive Strength
Indirect Tensile Strength
Flexural Strength
Flexural Modulus
Detailed Experimental Program

26. Characterization of the Granular Lateritic Soil
MATERIALS AND METHODS
Characterization of the Granular Lateritic Soil
Property
Lateritic soil
Gravel (%)
40.8
Sand(%)
50.1
Silt and clay (%)
9.1
Classification (as per USCS) SW
Specific Gravity
2.71
Liquid limit
48.25
plastic limit
31.58
Plasticity index
16.67
Natural moisture content 3%
OMC
12.7
MDD (kN/m3)
19.15

27. MATERIALS AND METHODS Unconfined Compressive Strength (UCS)
Indirect Tensile Strength (IDT)
Lateritic Soil + Cement % : 2, 3, 4, 6, 8, 10
Uniaxial Compression test
Strain rate: 1.25mm/min
It is a failure test 60
100
115
115

28. MATERIALS AND METHODS Flexural Beam Test
Monotonic flexure test for determining flexural strength (FS) or modulus of rupture (MOR);
Cyclic flexure test for determining the flexural modulus
CLS Beam Sample P 75
Monotonic Flexure Test
Flexural Strength

29. MATERIALS AND METHODS Cyclic Flexure Test Loading Frequency= 1Hz
time
Loading Frequency= 1Hz
Stress Ratio = 0.3
Flexural Modulus:

30. Ultrasonic Pulse Velocity Test on the Samples
MATERIALS AND METHODS
Ultrasonic Pulse Velocity Test on the Samples
Samples were prepared at OMC & MDD and cured for 28 days
Transducers used are of 50mm in diameter and maximum resonant frequency of 50 kHz.
Three replicate tests were conducted for each specimen in longitudinal direction and the average value was taken.

31. Introduction
Ultrasonic Pulse Velocity
Materials and Methods
Results and Discussions
Conclusions
References

32. RESULTS AND DISCUSSIONS
Relationship Between Ultrasonic Pulse Velocity and Cement Content
Pulse velocity varies from 1.18 km/s to 2 km/s for CLS for the cement dosage of 2% to 10%.
Strong correlation observed between cement content and pulse velocity.
Ultrasonic pulse velocity increases with increase in cement content, almost linearly, which is in line with the previous studies on cemented materials (Barisic et al. 2016).

33. RESULTS AND DISCUSSIONS
Relationship Between Ultrasonic Pulse Velocity and UCS value

34. RESULTS AND DISCUSSIONS
Relationship Between Ultrasonic Pulse Velocity and Flexural Strength

35. RESULTS AND DISCUSSIONS
Relationship Between Ultrasonic Pulse Velocity and IDT

36. RESULTS AND DISCUSSIONS
Relationship Between Ultrasonic Pulse Velocity and Flexural Modulus

37. RESULTS AND DISCUSSIONS
Relationship Between Constrained Modulus and Flexural Modulus

38. Introduction
Ultrasonic Pulse Velocity
Materials and Methods
Results and Discussions
Conclusions
References

39. CONCLUSIONS
Ultrasonic pulse velocity tests can ideally be used to assess the strength and stiffness parameters of the CLS used in subbase and base layers of any pavement.
Correlations developed under this study can be suitably used for the cement stabilized lateritic soils within the range of UCS from 2 to 10 MPa.ments.
More tests on similar materials need to be conducted for establishing generalized relationships.

40. Introduction
Ultrasonic Pulse Velocity
Materials and Methods
Results and Discussions
Conclusions
References

41. SELECTED REFERENCES
Austroads. (2012). Guide to Pavement Technology Part 2: Pavement Structural Design. Austroad, Sydney, Australia.
Barisic, I., Dimter, S. and Rukavina, T. (2016). Characterization of Cement Stabilized Pavement layers with ultrasound testing. Technical Gazette, 23 (2), 447‑453.
IS (1992). Method of Non-destructive testing of concrete, Part 1: Ultrasonic pulse velocity. Bureau of Indian Standard, New Delhi, India.
Mandal, T., Tinjum, J. M., Gokce, A., & Edil, T. B. (2016). Protocol for testing flexural strength, flexural modulus, and fatigue failure of cementitiously stabilized materials using third-point flexural beam tests. Geotechnical Testing Journal, 39(1),
Rio, L. M., Jimenez, A., Lopez, F., Rosa, F. J., Rufo, M. M. and Paniagua, J. M. (2004). Characterization and hardening of concrete with ultrasonic testing. Ultrasonics, (42), 527–530.
Yesiller, N., Hanson, J., Rener, A., and Usmen, M. (2001). Ultrasonic testing for evaluation of stabilized mixtures. Transportation Research Record: Journal of the Transportation Research Board, 1757,

42. Thank you
Thank You