. Daoud Use 1 of Micro Paver Program for Pavement Maintenance Management System (PMMS) of Roads in Central and Eastern Sudan

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1 . Daoud Use 1 of Micro Paver Program for Pavement Maintenance Management System (PMMS) of Roads in Central and Eastern Sudan ABSTRACT Dr Galal A Ali 1, Mohamed Eisa 2 and Elsir Suleiman 3 Pavement maintenance management system (PMMS) incorporates a systematic procedure for pavement evaluation using pavement condition index (PCI). They also determine effective and economic management of maintenance expenditures. PCI computation by PAVER or Micro PAVER is based on determination of defects. In this paper the Micro PAVER was applied to roads in central and eastern regions of Sudan. Field survey data on the road network carried out by the National Highway Authority (NHA) were used. A total of 676-km sections were selected from the central region. PCI was then computed following 8 sequential steps. To evaluate Port Sudan road network applying PAVER and Micro PAVER, visual inspection survey was conducted in Hadal zone, Port Sudan. The zone had 14 km of road network length. Data was analyzed by PAVER/Micro PAVER, PCI computed, conditions evaluated and the required maintenance determined. The Micro PAVER evaluation results indicated that 52.3 % of the distresses were attributed to environmental effects, 21.7 % were load-related and 26 % due to other causes. Performance curves were developed for 10- year analysis and prediction period for central Sudan road network. PCI values computed by the Micro PAVER were compared with NHA values obtained using PAVER manual. The comparison was favorable. Analysis of 41-km of Hadal road network sections using PAVER manual resulted in 94 % excellent and 6 % in very good condition. Maintenance actions recommended for Hadal roads were routine maintenance for 91 %, 8 % preventive maintenance and 1 % major rehabilitation. For localized maintenance, 76 % did not require maintenance, 41 % patching and 9 % crack/slurry seal. Evaluation of central Sudan roads showed need for maintenance and rehabilitation (M&R). The results indicated that the majority of these roads had low PCI. Lack of maintenance created severely distressed pavements requiring rehabilitation. Establishment of maintenance departments equipped with modern evaluation tools, financial capabilities and trained personnel cannot be overemphasized. The PAVER and/or Micro PAVER were found suitable to Sudan PMMS for their efficiency and simplicity of implementation. PCI.. - مستخلص PCI Professor Assistant Professor, and Consult Building Eng. (SES), and Road Sudan Research University of Science and Technology. 2. Institute, Consulting U. of Engineer, K. Khartoum, Sudan 3. Lecturer, Civil Engineering Department, Red Sea University, Port, Sudan Journal of BRR VOL 12 July

2 1. Introduction Pavement maintenance management systems (PMMSs) introduce systematic, objective and consistent procedure to evaluate existing and future pavement structural and functional conditions. PMMS also provides a means to help mange pavement maintenance expenditure more effectively and economically by incorporating in the system an applicable approach to manage pavements and allowing for multiple budget options and scenarios that assist in formulation of maintenance and rehabilitation works (4, 2). PMMS typically employs a pavement rating system known as pavement condition index (PCI) as the basis for evaluation of current and future pavement conditions. From the predicted future pavement condition, multiple budget and maintenance strategies can be run to determine the most cost-effective maintenance treatment for the pavement (3, 4). 1.1 Pavement distress and identification manual Pavement distress is caused by various factors or a combination of factors including lack of structural capacity, inadequate design, inferior material quality (5), poor construction techniques and/or lack of preventive maintenance (6). Pavement performance depends on proper design of both asphalt mix and the pavement structure. Dissatisfaction of both elements simultaneously will result in premature failure of the pavement as illustrated in Figure 1 (7). Fig. 1- Premature Failure of Ebeid Khatim Road(7) Surface distresses are broadly classified as several types of cracking, disintegration: in the form of raveling and weathering, potholes, rutting, corrugation, shoving, depression, etc. In general, pavement experts were able to identify around 19 distress types that may occur in flexible pavements (8). A detailed description of the entire distress types may be found elsewhere (9). The most worldwide distress manual with detailed information about each distress type in flexible pavements has been developed by US army corps of engineers (3), and later adopted by the American Society for Testing and Materials under the designation ASTM D for roads and parking lots (10). 2. Pavement Condition Rating: The PAVER method Several methods are in use for pavement condition rating. These include the UK Burro- Snaith Model, BSM, Oman PMMS and South Dakota method, to name a few (1, 11). PCI is an index which shows the present condition of pavement according to simultaneous Journal of BRR VOL 12 July

3 evaluation of distress type, density and severity The standard PCI uses a scale of 7 different categories; a specific version of PCI scale uses only 3 categories, with different colors assigned by Micro Paver to illustrate different situations within the scales. Concurrently, present condition is related to pavement quality (PQ) with the characterizing descriptions excellent, very good.etc. to fail. This relation between PCI and PQ is shown in Figure 2 (12). Also shown is the simplified custom version with quality scales reduced to three categories. Fig. 2- PCI-Pavement Quality Relation Source: Micro Paver 5.3 Manual (12) The Paver method relies on PCI to evaluate a pavement. Its computation is based on evaluation of pavement surface condition by determining distress type, extent and severity. The fact that the Paver evaluation method depends on nineteen defects ranks it the most detailed pavement management system. Evaluation process begins with field survey, dividing the road network into sections which in turn are subdivided into equal-distance units, 5-km in this study. Each unit must be evaluated by the Paver model. The calculation of PCI involves the following steps: Division of the pavement section into sample units; Determination of defect type, distribution and severity; Determination of the Deduct Value (DV) for each distress type and each severity level using the corresponding DV curves; Computation of total deduct value (TDV) as the sum of DVs of all distress types. Finding the corrected DV (CDV) accounting for interaction among distress types; Calculation of the sample unit PCI from PCI = CDV. The Section PCI is then the average of the PCI values obtained for the Section samples. Determination of the pavement section condition rating. The Micro PAVER computer program facilitates the evaluation of road network pavements. It is used as a pavement management tool to store the inventory information, distress data and pavement condition index (PCI) values. Condition assessment can be performed fast and easily by using this software. The Micro PAVER possesses capabilities of pavement network inventory; pavement condition rating; development of pavement condition deterioration models; performing condition analysis; determination of maintenance and rehabilitation (M&R) needs; and analyzing the corresponding different budget scenarios. Figure 3 shows the general framework, organization and operation of Micro Paver system. The PAVER and Micro PAVER methods have the advantages of possessing accumulative causes of distresses, detailed subjective distress identification photos, wellwritten manual and easy to understand and implement; and worldwide popularity. In this paper the Micro Paver was applied to roads in central and eastern regions of Sudan. Journal of BRR VOL 12 July

4 Network Inventory Network analysis Data Base Project analysis Inspection scheduling Project condition Detailed Condition Survey and Evaluation Budget scenario Actual budget Prioritize Identification of R &feasible M alternatives Work plan Project list Selection of best Alternatives Fig. 3 General Framework, Organization and Operation of Micro Paver System 3. Application of Micro PAVER to Central Sudan Roads 3.1 Data source and management A field survey of the functional condition of the country s road network was carried out by the National Highway Authority (NHA, 2005). The inspection covered the national highway paved Network in Sudan. For the purpose of this study, 5 road network links consisting of 7 sections for a total length 676 km were selected from the central region. Table 1 summarizes the characteristics and other details of the network road sections selected in Central Sudan (Figure 4). Each of the 7 network sections was uniform regarding traffic, geometry, pavement type, construction history and environment,. The sections were subdivided into units of 5-km long and 7-m wide providing unit area of 35,000 m 2 and having uniform pavement condition. Table 1 - Characteristics and other details of network roads selected in Central Sudan Link ID, Name and Construction Year Section ID Section Name Section Length, km Overlay Year & Type 09S1 Khartoum-Medani, S1/1 Khartoum-El-Kamleen AC* 09S1/2 El-Kamleen - Medani AC* M-S Medani-Sennar, 1980 M-S Medani-Sinnar E3 Sennar Kosti, E3/1 Sinnar-Jebel Moya 26 AC* 18E3/2 Jebel Moya- Kosti 99 AC* 13S3 Kosti-Elduwaim, S3 Kosti-Elduwaim ST** 13S2 Elduwaim-J Aulia, S2/1 Elduwaim-Jebel Aulia ST** *AC = asphalt concrete **ST = surface treatment Journal of BRR VOL 12 July

5 Figure 5 presents the hypothesized performance trends that were not monitored to include the effects of overlaying twice in 1978 and 1984, respectively (the red lines), but rather the full pavement life performance curve (blue line). Typical distress data entry to Micro Paver is illustrated in Figure Results, analysis and PCI output reports The Micro PAVER reports contain summary charts and values of pavement condition index (PCI) The chart reports include selected pavement statistics presented in chart format such as pavement area, number of sections, average section PCI and area weighted PCI grouped by pavement age. The PCI report provides comprehensive section information during the last inspection including section percentages corresponding to the conditions indicated (Figure 7), percentages and conditions for all sections (Figure 8). Fig. 5 - Construction and Overlay Records in Micro PAVER: Khartoum-Medani Link. Fig. 6 - Typical Distress Survey Data Entry into Micro Paver program Pct Sections Failed Very Poor Poor Fair Good Very Good Excellent Condition at Last Insp Fig. 7 Pavement Condition during the Last Inspection against Percentage of Section Avg Condition (PCI) Fig. 4 Central Sudan study location network Network ID Fig. 8 - Average Pavement Condition vs Network Section Numbers Journal of BRR VOL 12 July

6 Table 2 - Central Sudan road network sections: Percent of distress Deduct Values Section Name Section ID Section length, km % Loadrelated distresses % Climaterelated distresses Other causes Khartoum-El-Kamleen El-Kamleen - Medani 09S1/ Medani-Sinnar 09S1/ Sinnar-Jebel Moya M-S Jebel Moya- Kosti 18E3/ Kosti-Elduwaim 18E3/ Elduwaim-Jebel Aulia 13S Average percentage Fig. 9 - Percentages of Major Causes of Distresses in Central Sudan Road Network 3.4 Network condition analysis and prediction The Micro PAVER frequency report computes the excepted condition of each pavement section. The condition analysis views condition performance for each link or all network links including all sections of the link or links, as in Figure 10, as well as the individual sections. A typical performance curve is illustrated for the latter case in Figure 11 for 10-year analysis and prediction period. Fig Performance Curve for All Network Links and Deterioration with Time Journal of BRR VOL 12 July

7 Fig Performance Curve for El-Kamleen- Medani Section and Deterioration with Time 3.5 Comparison of PCI values from Micro Paver with the corresponding NHA values: Central Sudan network sections Figure 12 presents a comparison between the PCI values computed using the Micro Paver with the corresponding NHA values for Central Sudan network sections. The PCI values for all sections are shown on the bar chart. The figure indicates that the comparison is favorable although the NHA used the manual procedure. However, there is a distinct difference between the two determinations for Sennar Jebel Moya section probably due to the short length of the section, 26 km only while the other six sections are around 100-m long. Since the Micro Paver applies a precise computational program, the NHA method might have not been capable of predicting a more accurate PCI value for this section due to less number of 5-km sample units to provide a reliable average for the section. Fig Comparison of PCI values from Micro Paver with the Corresponding NHA values: Central Sudan network sections 4. Application of Micro PAVER to Eastern Sudan Roads 4.1 Data source and management To analyze Port Sudan road network using PMMS technique, detailed visual inspection survey was conducted to Hadal zone illustrated in Figure 13 (15). The zone had about 14 km of road network length. A pavement condition inspection form to contain the data of all sections of Hadal road network was prepared for this purpose. An objective of this study was to investigate the possibility of applying the Micro PAVER to much smaller network length compared to the network of section 3 above. Journal of BRR VOL 12 July

8 The inspection data was analyzed by the PAVER method and Micro PAVER software to determine the PCI value for each section of the zone network. The results were then evaluated to determine the surface condition of the network roads and the required maintenance. Acquiring data required for the application of Micro PAVER and the application of the system were considered in a manner similar to that executed in the central network study. However, the observed number of distress types was 8 types rather than the identified 19. This was due to the ages of the road network which were in the range of 2-4 years in service, and the nature of the city traffic compared to rural and suburban commercial traffic. Fig. 13 Eastern Sudan Study Location Network: Hadal Zone, Port Sudan (14) 4.2 Hadal road network condition assessment and prediction After inspection of Hadal road network, condition assessment of each section was performed using both manual PAVER and Micro PAVER software. The PCI value for each section was determined and the current condition identified. Over time, Port Sudan PMMS database will contain a great amount of historical pavement condition data regarding the network. This information can be used to develop pavement performance models that predict pavement performance. Table 3 summarizes the % of Deduct Values for the three causes of distresses. Journal of BRR VOL 12 July

9 Table 3 Per cent of Deduct Values for various Section ID distress causes Loadrelated cause Climaterelated cause Other causes Average Generating strategies for maintenance actions Establishment of Port Sudan pavement management system requires development and application of maintenance strategies in order to effectively maintain the roadway network. The maintenance options when combined with identified road condition, such as PCI, lead to determination of specific maintenance and rehabilitation actions (15). Figures 14a and 14b present, respectively, suggested feasible maintenance and rehabilitation (M&R) options for Hadal and Port Sudan road networks according to PAVER maintenance strategies. It is worth mentioning that for the entire city network the other M&R actions shown in Figure 14b should be considered in addition to those of Figure 14a to account for the lowrated road sections. The broad maintenance and rehabilitation strategies needed for roadway network will be determined based on current PCI of pavements. Thereafter, the road maintenance agency will be able to plan and prepare budget needed at the network level. Recommended M&R actions based on calculated PCI PCI = PCI = PCI = PCI = No maintenance (Do Nothing) Routine maintenance Preventive maintenance Corrective maintenance Fog seal Crack sealing Local repairs Drainage cleaning Slurry seal Thin overlay Chip seal Partial patching Full depth patching Milling Figure 14a - Proposed alternative M&R actions for Flexible Pavements of Hadal Road Network (PCI ) Journal of BRR VOL 12 July

10 PCI = PCI = PCI = 0-25 Minor rehabilitation Major rehabilitation Reconstruction 50 mm overlay with patching Milling plus 50mm overlay Recycle and recompact plus 75 mm overlay 75 mm overlay with patching Removal and replacement of entire pavement structure Geometric and safety improvement 200 mm recycle plus 40 mm AC overlay Figure 14b - Proposed alternative M&R actions for Flexible Pavements of Port Sudan City Road Network (PCI 0-55) 4.4 Results and analysis of Hadal road network Analysis of Hadal roads network resulted in 94% of sections in excellent condition and 6% were in very good condition according to PAVER manual method. Application of the Micro PAVER method resulted in 9 % satisfactory, 82 % in good condition and 9 % in fair condition. Regarding maintenance action for Hadal road network sections, 91% need routine maintenance, 8% require preventive maintenance and 1% needs major rehabilitation. In term of localized maintenance for the network, 76% do not require maintenance action, 9% need surface patching, 6% deep patching, 6% crack sealing and 3% slurry seal. 5. Conclusions and Recommendations Condition evaluation of central Sudan road network showed that the current status is in urgent need of an emergency program for pavement maintenance, rehabilitation and reconstruction. The results of the study for the 676-km road network in the area indicated, in general, that the majority of these roads possessed high distress indices and low values of pavement condition index (PCI) irrespective of the road classification. The lack of maintenance over the past decades created severely distressed pavements requiring comprehensive rehabilitation programs. The current maintenance practices are not based on scientific procedures. Appropriate methods should be developed and adopted to assist in the decision-making process related to improvement and upgrading significant parts of the road network. To accomplish such requirements utilizing advances and recent techniques in pavement industry, related authorities should resort to development of appropriate pavement maintenance management systems (PMMSs). These are crucial prerequisites to proper pavement performance evaluation and implementation of applicable maintenance policies for satisfactory performance during the design life. A typical situation might be cited for Port Sudan urban roads following the construction of extensive road network. Journal of BRR VOL 12 July

11 Establishment of maintenance departments within all road agencies in the country cannot be overemphasized. These departments should be equipped with modern evaluation tools, software computer programs, financial capabilities and trained personnel. As a demonstration, the authors are obliged to cite the unsatisfactory (using a mild describer) maintenance situation sponsored by the Ministry of Planning and Urban Development. The most suitable evaluation criteria to Sudan pavement network conditions are either PAVER manual or Micro PAVER software for their efficiency and simplicity of implementation. Acknowledgement The authors would like to thank Dr Kamal Margi for his assistance in providing part of the data and during the analysis phase. 6. References [1] Ali, Galal A and K Al-Qatabi, Efforts in Road Maintenance Management in Oman: Development and Sensitivity Analysis, Proceedings, International Conference on Roads and Road Transport Problems (ICORT-95), New Delhi, India, Vol. 1, pp , 1995 [2] Hass, R, Hudson and Zaniewski, Modern Pavement Management, In Arabic Translation by Al-Suhaibani, A and A Al- Mansour, King Saud University Press, 2003 [3] Shahin, MY, Pavement Management for Roads, Airports, and Parking Lots, New York, Chapman and Hill, New York, 1994 [4] Transportation Research Board (TRB), Pavement Management System Based on Financial Consequence, in Pavement Management, Transportation Research Record, Journal of the TRB, Washington, DC, USA, Issue No. 1940, 196 pp., TRB, 2005 [5] Kaloush, K., Sousa, J., Way, G and Galal Ali, Observations on the Development and Use of SHRP scn mi oirup dtugi gised irsr n G MDGier eds ids Mud or snes Mudir, 3 rd Gulf Conference on Roads, Muscat, Oman, pp , 2006 [6] Al-Mansour, A and Al-Mubaraky, M, Development of Flexible Pavement Distress Model for Riyadh City, Saudi Arabia, Al-Azhar University Engineering Journal Vol.2, No.3, 2007 [7] Ali, Galal, New Technology in Highway and Pavement Industry, Seminar organized by Ministry of Physical Planning & Public Utilities and CETS, Khartoum, Sudan, August 2003 [8] Huang, YH, Pavement Analysis and Design, University of Kentucky, USA, Pearson Prentice-Hall, 2 nd Ed, 2004 [9] Eisa, M and G Ali, Application of Micro PAVER Program for PMMS of Central Sudan Roads, MSc Thesis, Sudan University of Science and Technology, Khartoum, Sudan, 2011 [10] ASTM, Standard Practice for Surveys of Roads and Parking Lots Pavement Condition Index, ASTM D6433, American Society for Testing and Materials, USA, 2003 Journal of BRR VOL 12 July

12 [11] Suleiman, E and Galal Ali, Pavement Maintenance Management System: Port Sudan City Road Network as Case Study, MSc Thesis, Sudan University of Science and Technology, Khartoum, Sudan, 2011 [12] Shahin, MY, M Justice and JA Walther, PMMS for Roads and Streets Using the MICRO PAVER Pavement Management System, Technical Report MO-90/05 US Army ERDC-CERL and [13] National Highway Authority, Pavement Condition Survey Manual. Ministry of Roads and Bridges, Khartoum, Sudan, 2005 [14] Google website, Google Earth, [15] Hicks, RG, K Dunn, and JS Moulthrop, Framework for Selecting Effective Preventive Maintenance Treatments for Flexible Pavements, in Transportation Research Record 1597, TRB, National Research Council, Washington, D.C., 1997, pp Journal of BRR VOL 12 July