| Author | Raza, Danish |
| Call Number | AIT Thesis no. TE-95-04 |
| Subject(s) | Pavements--Pakistan--Maintenance and repair
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering, School of Civil Engineering
|
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. TE-95-04 |
| Abstract | The highway network of Pakistan is being constantly deteriorated under extreme weather
conditions and heavy weights of over-loaded trucks. The National Highway Authority (NHA) is
the agency responsible for maintenance and repair activities on these roads. NHA holds road
condition surveys annually to find out the extent and severity of pavement deterioration. The
decision of triggering the maintenance activities for a pavement section is currently based on a set
of intuitively decided weightage factors assigned to these distresses and other variables. This
decision involves a lot of variables which not only makes it difficult for the manager but
umeliable too. Lack of a proper decision policy can lead to the misuse of valuable funds. This
study presents a systematic approach to evaluate the present serviceability of a pavement section,
predict the future condition of the pavement network and calculate the future budget requirements
on the basis of this prediction.
The approach used in the first step (evaluation of present serviceability) is multiple
regression analysis between the present serviceability rating (given by a panel of highway users)
as dependent variable and some of the most important factors influencing the pavement
performance (including longitudinal roughness, cracking ratio, rut depth and average daily traffic)
as the independent and/or explanatory variables.
Two most important highways of the network, NS and NSS, were studied and
performance evaluation models for both of them were developed. A combined model for the
whole network was also developed using the same technique.
The deterioration model for pavement performance was developed using a S-state Markov
process model with time independent, stationary transition probabilities calculated on the basis of
aggregation of seven years of data. The Markov process was defined by dividing the newly
defined 10-point pavement serviceability index PSI 10 into five states of 2-points each. State-I was
defined as the best condition state comprising of PSI 10 values ranging between 8 to 10. State-S
(PSI 10 = 0-2) was practically a never reaching state because any pavement section would
definitely be rehabilitated before reaching this condition. Transitions of pavement sections from
one state to another were accumulated to formulate the transition probability matrices for both
routes NS and NSS. Transition probability matrix for the whole system was also determined with
the help of combined data.
The existing system of decisions about putting a pavement section under maintenance
activities was critically examined and was found to be not correlated with the functional
performance of the pavements. A regression analysis between PSI 10 and the MIL (maintenance
intervention level) scores calculated by NHA was performed for this purpose. Finally, decision
criteria based on pavement performance and its acceptability survey was presented and
demonstrated with future budget demand calculation. |
| Year | 1996 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. TE-95-04 |
| Type | Thesis |
| School | School of Civil Engineering |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Transportation Engineering (TE) |
| Chairperson(s) | Chen, Jian-Shiuh; |
| Examination Committee(s) | Yordphol Tanaboriboon;Okuyama, Yasuhide;Noppadol Phien-Wej ; |
| Scholarship Donor(s) | Government of Japan |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1996 |