Abstract

The concept of transfer functions is well entrenched in mechanistic-empirical (ME) pavement design and essentially represents the performance component of ME design. Initially, transfer functions were relatively simple linear log-log functions relating some critical pavement response parameter to the number of load repetitions that can be sustained at the level of the critical response parameter before a predefined level of damage is reached. Later, given more advanced computing software, the formulation of transfer functions evolved to include continuous, nonlinear models. However, all these models have one common characteristic in the sense that they all include the number of load repetitions in the model formulation. This requires the use of a “time-hardening” approach to accumulate damage under mixed traffic and environmental conditions in a recursive damage simulation process. Unfortunately, the time-hardening process is associated with large numbers of calculations to evaluate the equivalent number of load repetitions at every instance in which the traffic load or pavement variables change. This article presents an alternative approach to the formulation of damage models that is based on the Markov property of memoryless systems. The advantage of using the memoryless model formulation in a recursive damage simulation process is that the calculation of the equivalent number of load repetitions is eliminated from the process. The recursive damage simulation process can also be initiated at any level of damage without knowing the prior history that caused the damage. The formulation and calibration of memoryless damage models are illustrated for the fatigue and plastic strain damage of asphalt concrete mixes.

References

1.
AASHTO
Guide for the Design of Pavement Structures
,
American Association of State Highway and Transportation Officials
,
Washington, DC
,
1993
, 624p.
2.
Theyse
,
H. L.
,
de Beer
,
M.
, and
Rust
,
F. C.
, “
Overview of South African Mechanistic Pavement Design Method
,”
Flexible Pavement Design and Rehabilitation Issues, Transportation Research Record, No. 1539
,
National Research Council
,
Washington, DC
,
1996
, pp. 
6
17
.
3.
NCHRP
Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures, Final Report NCHRP Project 1-37A
,
Transportation Research Board, National Research Council
,
Washington, DC
,
2004
, 219p.
4.
Ullidtz
,
P.
,
Harvey
,
J.
,
Tsai
,
B.-W.
, and
Monismith
,
C.
,
Calibration of Incremental-Recursive Flexible Damage Models in CalME Using HVS Experiments, Research Report UCPRC-RR-2005-06
,
University of California, Pavement Research Center
,
Berkeley and Davis, CA
,
2006
, 222p.
5.
Theyse
,
H. L.
, “
The Precision and Accuracy of Mechanistic-Empirical Pavement Design
,” presented at the
Tenth International Conference on Asphalt Pavements
,
Quebec, Canada
, Aug. 12–17,
2006
,
International Society for Asphalt Pavements
, Lino Lakes, MN, pp. 
987
998
.
6.
Monismith
,
C. L.
,
Ogawa
,
N.
, and
Freeme
,
C. R.
, “
Permanent Deformation Characteristics of Subgrade Soils due to Repeated Loading
,”
Transp. Res. Rec.
, No. 
537
,
1975
, pp. 
1
17
.
7.
Wolff
,
H.
, “
Elasto-Plastic Behaviour of Granular Pavement Layers in South Africa
,” Ph.D. thesis,
University of Pretoria
, Pretoria, South Africa,
1992
.
8.
Steven
,
B. D.
, “
The Development and Verification of a Pavement Response and Performance Model for Unbound Granular Pavements
,” Ph.D. thesis,
University of Canterbury
, Christchurch, New Zealand,
2005
.
9.
“Markov Property,” Wikipedia, The Free Encyclopedia, https://web.archive.org/web/20180306105043/https://en.wikipedia.org/wiki/Markov_property (accessed 17 March
2017
).
10.
Harr
,
M. E.
,
Mechanics of Particulate Media
,
McGraw-Hill
,
New York
,
1977
, pp. 
72
73
.
This content is only available via PDF.
You do not currently have access to this content.