Highway Maintenance Project
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This report summarizes a highway maintenance project for roads in the Nazzal Area near Al-Hayat Hospital in Amman, Jordan. Samples from 23 sections totaling 37 samples were examined for distresses including cracking, patching, potholes, and others. Distress types, severity and quantities were documented along with proposed repair methods. Pavement condition index values were calculated for each section, with most ranging from good to excellent condition. The report concludes with recommendations for repairing the few sections with PCI values below 80.
Highway Maintenance Project
- 3. 1.1 Introduction: This report is a maintenance report that contains photos for distresses, PCI calculation, and suggested repairs and maintenance for the selected road To do any maintenance project we must work and identify some things as follows: a) Network: Amman ( Capital of Jordan ) b) Zone: Nazzal Area c) Branch: Around Al-Hayat Hospital d) Section: is selected by: - Pavement Structure - Traffic - Construction History - Pavement Rank - Drainage facilities and shoulders - Condition e) Sample: For an area of (2500±100) Ft² or (139~325) m²
- 4. The roads were divided into several sections and every section will contain several samples…Therefore, samples were selected by calculating areas and measuring length and width for each road. A twenty-three sections were assigned, and thirty-seven samples were divided by calculation of areas or length of each section. 1.2 Problem Decision After the samples were separately divided to the students, each distress will be identified by its degree and treatment method for each sample. In the samples that we discovered, we have the following Distresses: Long & Transverse Crack Block Cracking Patching & Utility Cut Patching Alligator Cracking Potholes Depression Edge Cracking Lane & Shoulder drop off The Figures below show pavement condition based on PCI ratings…
- 5. 1.3 Definition of Repair Options for Asphalt Pavements 1- Cold Milling - Carbide teeth cutting bits are used to chip off the surface of the pavement to remove material. 2- Heater Scarify - 3/4 inch of the pavement is heated and scarified to provide a smooth, crack-free surface. Can be used before overlaying to slow reflective cracking.
- 6. 3- Overlay - An application of asphalt concrete over the existing surface to correct surface deficiencies and / or increase the load carrying capacity of the pavement. 4- Patching Shallow - A stable, compacted leveling course is placed in depressions to level off the surface. Partial depth - the deteriorated area of the asphalt surface course is removed and replaced. Full depth - the deteriorated area of the asphalt surface course and the base course are removed and replaced. The sub-grade is re- compacted. 5- Reconstruction - complete replacement of the pavement 6- Recycle - the reworking of a pavement structure or its component material to improve their performance and correct noted deficiencies. 7- Seal Cracks - cracks are often routed to remove debris before sealing. 8- Surface Seal - an application of bituminous spray, such as for seals and rejuvenators.
- 7. 9- Surface Treatment - an application of bituminous binder with aggregate, such as sand seals, slurry seals, and chip seals. Calculations Graphs & Excel tables are attached in this report… 1.4 Distress Definitions We would like to tell you about each distress, description, how to measure, photos that we captured. 1-Long & Transverse Crack: Longitudinal cracks are parallel to the pavement's centerline or lay down direction. Transverse cracks extend across the pavement at approximately right angles to the pavement centerline or direction of lay down. These types of cracks are not usually load- associated. Measured in linear ft or m. 2-Block Cracking: are interconnected cracks that divide the pavement into approximately rectangular pieces. The blocks may range in size from approximately 1 by 1 ft (0.3 by 0.3) m to 10 by 10 ft (3 by 3) m. Block cracking is
- 8. caused by shrinkage of the asphalt concrete and daily temperature cycling. Measured in squared meter. 3-Patching: A patch is an area of pavement that has been replaced with new material to repair the existing pavement. Measured in squared meter. 4- Alligator Crack: is a series of interconnecting cracks caused by fatigue failure of the asphalt concrete surface under repeated traffic loading. Alligator cracking is considered a major structural distress and is usually accompanied by rutting. Measured in squared meter. 5-Potholes: are small-usually less than (0.9m ) in diameter-bowl shaped depressions in the pavement surface. They generally have sharp edges and vertical sides near the top of the hole. Potholes are counted in numbers 6-Depression: are localized pavement surface areas with elevations slightly lower than those of surrounding pavement. They are created by
- 9. settlement of the foundation soil or are a result of improper construction. Measured in squared meter. 7- Edge Cracking: are parallel to and usually within 0.3 to 0.6 m of the outer edge of the pavement. This distress is accelerated by traffic loading and can be caused by frost weakened base or sub grade. Measured in squared meter. 8-Lane & Shoulder Drop Off: is a difference in elevation between the pavement edge and the shoulder. This distress is caused by shoulder erosion, shoulder settlement, or by building up the roadway without adjusting the shoulder level.
- 10. 1.6 Discussion & Conclusion: The branch is a local branch… so it is not exposed to heavy traffic. Hence the abundance of block cracking, block cracks occur in low traffic or no traffic area. The main reason for block cracking is shrinkage and not load associated. The majority of sections have a PCI value over 80 . some sections are new… For example: section 2 has a PCI value 57. So it need to seal crack and overlay. It depends on the highest deduct value for repairing.
- 11. Section No. Length (m)width (m) SamplesSelected Type Severity Measure Potholes L 1 M (1.5*4) m² M (1*8) m² H (1.7*6) m² Alligator Crack M (2.9*1.9) m² Depression M (0.64*0.56) m² L& TCracking H 27 m Edge Crack M (1*1.5) m² Patching L (3*4) m² L& TCracking L 5 m Depression M (0.25*0.56) m² Potholes H 1 Alligator Crack M (3*1.5) m² Depression H (0.51*0.4) m² Block Cracking M (2.5*2) m² L& TCracking L 8 m Depression M (0.19*0.42) m² Block Cracking H (2*3) m² Patching L (1*1.5) m² Alligator Crack L (1.2*1.7) m² Edge Crack L 0.7 m Lane Drop Off L 0.13 m Potholes M 1 L& TCracking M 38 m Depression H (0.23*0.35) m² 10 31,93 13 1 L& TCracking M 8 m 11 46 13 1 Block Cracking M (4.9*1.3) m² 12 82,82 13 2 L& TCracking L 6.18 m 13 77,89 13 2 Block Cracking M (3.1*1.4) m² 14 49,1 13 1 L& TCracking M 6 m M 7 m L 2 m 16 50,94 13 1 Patching M (0.7*10) m H 3 m L 1.6 m 18 45,26 13 1 Alligator Crack H (6.5*0.9) m² Alligator Crack M (7.2*0.9) m² Block Cracking M (7*1.9) m² L& TCracking M 13 m Block Cracking M (2.72*2) m² 21 155,9526 13 3 L& TCracking M 10 m Depression M (0.5*0.6) m² L& TCracking H 20 m Pothle M 3 patching M (2*1.9) m² Block Cracking H (1.9*2.5) m² Edge Crack M 1 m Patching L (1.5*0.85) m² Distress Block Cracking 1 2 2 1 Section 107,7718 13 30,09 13 225,6927 13 36 3 2 14 25 96,2029 13 42,0233 13 93,7211 13 7 1 8 1 33,679 13 44,3247 13 9 1 15 1 23 2 46,2487 13 19,77 13 57,75 13 41,56 13 87,72 13 L& TCracking 17 1 L& TCracking 19 1 20 72,24 13 2 22 209,4782 13 4
- 12. section no. section pci rating 1 89 excellent 2 57 good 3 84 very good 4 65 good 5 65 good 6 95 excellent 7 84 very good 8 98 excellent 9 81 very good 10 93 excellent 11 82 very good 12 81 very good 13 89 excellent 14 85 very good 15 92 excellent 16 85 B17 very good 17 88 excellent 18 62 good 19 72 very good 20 89 excellent 21 70 good 22 77 very good 23 80 very good