Cultural Exchange Program between Egypt and Bulgaria Fayoum University

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1 Fayoum University Maintenance Decisions Due to traffic loading and the environment, pavements gradually deteriorate in serviceability with time to a terminal level, which may be defined as failure. The rate of deterioration often accelerates as failure approaches. To reduce the rate of deterioration, Maintenance and Rehabilitation (M&R) activities should be applied through a maintenance plan to preserve pavement condition, safety, and ride quality, leading to achieving pavement design life in a cost effective manner 1 2

2 Maintenance Decisions How can we get the Maintenance Decision? 3 R 3 W How can we get the Maintenance Decision? Right Treatment on the Right Pavement at the Right Time 3 4

3 How can we get the Maintenance Decision? is the suitable Maintenance Decision? How can we get the Maintenance Decision? Where is the suitable section To begin with? Where 5 6

4 How can we get the Maintenance Decision? When should be applied? When How can we get the Maintenance Decision? Where When 7 8

5 Distress-By-Distress Surface Treatment Milling & Overlay Reconstruction Number of Sections 3 Sections Maintenance Alternatives (Maintenance Alternatives) 3 Maintenance Alternatives 2 = 8 Alternatives Do Maintenance Do Nothing Number of Sections 9 10

6 Number of Sections 10 Sections Maintenance Alternatives (Maintenance Alternatives) 10 Maintenance Alternatives Do Maintenance Do Nothing 2 = 1024 Alternatives Number of Sections Maintenance Alternatives Number of Sections Maintenance Alternatives Do Nothing Surface Treatment 200 Sections Milling & Overlay Reconstruction for AC Layers (Maintenance Alternatives) Reconstruction up to Subgrade Number of Sections = Number cannot be written 11 12

7 Maintenance Decision Decision Tree Most of highway agencies identify pavement maintenance needs based on a single index such as the Pavement Condition Index (PCI), which is a good indicator for general pavement condition, but not necessarily as good in determining appropriate maintenance treatments. Furthermore, some highway agencies make maintenance decisions based on individual distress levels to avoid complex combinations between distress levels (types, quantity, and severity) and possible maintenance alternatives, of which many are possible. To consider all possible combinations, a large number of alternatives arise

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10 10 Distress Types L M H L M H L M H L M H M&R Alternatives Huge Number of Condition States Schematic Illustration of the Relationships Between Distress Levels and Maintenance Alternatives If the condition states were regrouped into smaller representative numbers (say three or four), then the number of analysis schemes in a typical decision tree (e.g., if then else) could be significantly reduced. The following simple principles illustrate how to address the complex combinations between distress levels and possible maintenance alternatives 19 20

11 10 Distress Types L M H L M H L M H L M H M&R Alternatives Distress-By- Distress Repair Patching Crack Sealing Surface Dressing Localized Repair State Schematic Illustration of Reducing the Number of Analysis Using Localized Maintenance In this regard, research was initiated by Abo-Hashema et. al at Cairo University in Egypt aiming to develop an integrated practical decision tree based on the previous concept to assist highway agencies in identifying the current maintenance needs. The developed decision tree builds its maintenance decision criteria on the basis of the density of required localized maintenance (patching, crack sealing, etc.) and not on the basis of the distress density (Abo-Hashema and Sharaf 2004, Abo-Hashema 1999)

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