Highway Drainage & Maintenance by Haryati yaacob(fka, utm)

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Osborne Walsh
5 years ago
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1 Highway Drainage & Maintenance by Haryati yaacob(fka, utm)

2 Highway Drainage & Maintenance Highway Drainage System Highway Maintenance Pavement Rehabilitation Visual Assessment of Flexible Pavement Surface Conditions

3 Highway Drainage System Adequate & proper road drainage is VERY, VERY, VERY IMPORTANT! Both for the safety of road users and pavement construction and maintenance 1. User safety accumulated water caused hydroplaning, splash and spray 2. Pavement - reduce sub-grade strength, hydraulic pressure from passing traffic, binder stripping, slope stability Two types of drainage: 1. Sub-surface drainage cut/fill area, high water table 2. Surface drainage rain, snow, run-off water

4 Surface Drainage System Road surface need to be free of standing water to ensure safety To intercept surface and watershed run-off into designed channel for discharge into river or natural waterways Types of surface drainage system: 1. Transverse slope/crown facilitate removal of surface water 2. Longitudinal slope optional, help expedite water flow 3. Interceptor drain at top of cut area to prevent water from flowing onto pavement, erosion, discharge into paved spillway/outfall 4. Side drain alongside of highway to collect water from pavement surface, subsurface and ROW 5. Curb,Gutter and Scupper drain drainage, embankment erosion, and encroachment (urban) 6. Culvert under pavement, carry water across road 7. Bridge across river or waterway, part of a road

5 Crowned Roadways Road surface normally cambered or superelevated to facilitate the removal of surface water from the road surface

6 Side Drain alongside of highway to collect water from pavement surface, subsurface and ROW

7 Berm/Interceptor Drain at top of cut area to prevent water from flowing onto pavement, erosion, discharge into paved spillway/outfall

8 Toe Drain To collect water that has fallen on the batters of embankment to the point of disposal.

9 Cascade Drains/ chutes/spillway an open or close channels to carry water down the cut or embankment slopes.

10 Curb and gutter

11 Curb & Gutter

12 Culvert under pavement, carry water across road

13 Culvert

14 Bridge

15 Koror-Babeldoub ( )

16 Sub-surface Drainage System Provided within the pavement to lower the water table, intercept seepage from cut or sidehill, and drain out seepage water from pavement structure If inadequate premature destruction of pavement (high pore pressure, frost action), slope failure (increase stress, reduce shear strength) Usually installed on expressway and trunk road Three major sources of underground water: 1. Natural ground water (WT) seasonal 2. Capillary action move upward tru underlying soil strata, particle size dependent 3. Seepage permeated tru slope, pavement, road shoulder

17 Source of ground water Seepage from higher ground Road pavemen t Through permeable surface Subgrade Road shoulder Seepage from road shoulder Capillary rise Water table fluctuation Water table

18 Longitudinal drain filtered perforated pipe along road shoulder - Water table < 1m beneath the formation level

20 transverse drain if longitudinal not adequate

21 Interceptor Drain/Pipe A subsoil drain installed at the toe of cut slope to intercept seepage water in the cut slope from flowing down into the subgrade.

22 Drainage Blanket Upward movement by capillary rise can be controlled by providing a layer of high coefficient of permeability beneath or between road layers to transport water to the roadside drains.

23 Maintenance Pavement maintenance is required to keep road network in satisfactory conditions to ensure safety and low road user costs Consist of (component based): 1. Resurface and patching 2. Shoulder maintenance and grass cutting 3. Repair and stabilized slope 4. Clean, repair, reconstruct culvert, bridge, and drains 5. Maintenance of road furniture and markings Does not includes widening and structural strengthening

24 Maintenance Maintenance activities (frequency based): 1. Routine carried out at least once a year, usually small scale/simple, can be carried out on a regular basis (grass cutting, patching, crack sealing, shoulder re grading, drainage, maintenance of road furniture) 2. Periodic carried after once in a few years, normally large scale, require specialized equipment and skilled manpower, costly and need proper identification and planning (preventive maintenance work, pavement strengthening, resurface ) 3. Emergency works- beyond control, need to be dealt without delay (landslides, embankment failure, collapse of bridge) Routine and periodic maintenance needed to maintain at acceptable safety level and to avoid costly repair

25 Maintenance - Patch

26 Maintenance - Drain

27 Maintenance - Road Marking

28 Maintenance Furniture, Landscape

29 Maintenance - Slope Failure

30 Maintenance - Slope

31 Maintenance - Culvert

32 Maintenance - Bridge

33 Maintenance - Other

34 Pavement Rehabilitation Rehabilitation carried out when routine and periodic maintenance are no longer adequate and traffic growth demands for strengthening/widening or improvement Various techniques, selection depends heavily on engineering judgment but other factors such as cost, construction feasibility and effect on road users should be considered as well. Rehabilitation methods: 1. Restoration 2. Resurfacing 3. Recycling 4. Reconstruction

35 1. Restoration When distress limitted to surfacing, such as cracking and polishing. Restoration will repair existing distress, reduces roughness rate and slow down pavement deterioration.

36 Restoration - Rejuvenating Rejuvenators is a spray applied liquid asphalt restoration product that actually penetrates the asphalt with a combination of bitumen and solvents. restores the flexibility and appearance to new condition. recommended for asphalt that has not been sealed previously, and area of moderate to heavy traffic. have pavement preservation benefits

37 A rejuvenator should not be applied to a pavement having an excess of binder on the surface. The amount of air void in the HMA being rejuvenated should be at least 5 percent to ensure proper penetration of the rejuvenator into the pavement. Rejuvenators should be applied in hot weather, above 20 C (70 F), so that the rejuvenator will penetrate more deeply into the asphalt pavement and will cure sooner. Before rejuvenating After rejuvenating

38 Restoration-Cutting and Patching Replacement of deteriorated asphalt surface with the new bituminous mixture, placed and compacted to the same level with the surrounding surface. Patching material can be just about any HMA or cold mix asphalt material as well as certain types of slurries.

39 Patches can be either full-depth where they extend from the pavement surface to the subgrade ( Figure 10.12) or partial where they do not extend through the full depth of existing pavement ( Figure 10.13). Full-depth patches are necessary where the entire depth of pavement is distressed.

Method of patching: 1. "Scoring" or cutting the pavement beyond the distressed area. 2. Removal of distressed pavement (debris asphalt is returned to asphalt producer plants for recycling). 3.

40 Method of patching: 1. "Scoring" or cutting the pavement beyond the distressed area. 2. Removal of distressed pavement (debris asphalt is returned to asphalt producer plants for recycling). 3. Base/sub-base stabilization and compaction. 4. Applying "tack oil" to all existing pavement edges bonding the new pavement to existing pavement, and providing a seal. 5. Placement and compaction of new hot mix asphalt material.

41 Maintenance - Patch

42 Good patching jobs include cutting the area around the patch, not just throwing asphalt into the hole.

Restoration - Thin Bituminous Overlay Also known as non-structural overlay do not involve extensive structural design and generally contribute little to a pavement's structural capacity. Used to: 1.

43 Restoration - Thin Bituminous Overlay Also known as non-structural overlay do not involve extensive structural design and generally contribute little to a pavement's structural capacity. Used to: 1. Improve ride quality. 2. Correct minor surface defects. 3. Enhance appearance. 4. Reduce road-tire noise 5. Extend pavement service life. 6. Improve safety characteristics such as skid resistance and drainage.

Bitumen will secure the chippings and seal old road

44 THREE common used method: 1. Surface dressing Bitumen emulsion sprayed onto road surface, immediately followed by single or multiple cover of chippings to the bitumen using large spreader. Bitumen will secure the chippings and seal old road surface, preventing ingress of water. Chippings will restore texture of road surfaces, preventing skidding accidents.

surface which is found to be in relatively good shape.

45 2. Slurry seal Mixture of fine aggregate, filler or emulsified bitumen that has a creamy fluid-like appearance Normally be placed over an existing asphalt surface which is found to be in relatively good shape. Able to extend the life of the existing pavement by 5 to 7 years. PHOTOS SHOW HOW SLURRY SEAL IS APPLIED

46 3. Thin hot mix overlay Hot asphalt mix of less than 40 mm thickness Effective for Flexible and Rigid Pavements Improves Life Cycle Cost

47 Restoration Crack Sealing

48 2. Resurfacing When pavement have severe and extensive structural damage - structural improvement required Most popular in Malaysia Involved placement of fresh material improves riding quality, enhance structural strength Need to properly design the overlay thickness to achieve design life Using thick asphalt overlay with or w/o prior granular overlay (pre-treatment required) Video

49 3. Recycling Use of old pavement material to correct raveling, bleeding and improve skid resistance Types of recycling: 1. Hot recycling repair surface crack, road base still sound, use heat to soften surface 2. Cold recycling milling defected surface and reuse with addition of stabilizer, rejuvenator or bitumen 3. Base recycling road base fail, use stabilized old surface material as base, lay new surfacing

50 Hot in Place Recycling (HIPR) repair surface crack, road base still sound, use heat to soften surface HIPR video

51 Cold in Place Recycling (CIPR) milling defected surface and reuse with addition of binding agent (emulsion, foamed bitumen or cement) - Use as RB CIPR video

52 Reconstruction Removal and rebuilding of all or part of pavement using fresh material (current practice recycle) and new construction specification Pavement failed severely where deterioration has been allowed to occur w/o maintenance, or inadequate sub-surface drainage Types of reconstruction: 1. Hot recycling with overlay 2. Cold recycling with overlay 3. Construction/improvement of sub-surface drainage

53 Visual Assessment of Pavement Surface Conditions Assessment of pavement surface conditions used by highway agencies to: 1. Measure the ability of pavement to continue to provide service to public 2. Determine deficiencies and inadequacies of pavement 3. Determine remedial measures to be taken and its fiscal needs 4. Planning and programming of pavement maintenance and/or rehabilitation

54 Visual Assessment of Pavement Surface Conditions Types of distress in flexible pavement: 1. Cracks 2. Surface deformation 3. Surface defects 4. Patches 5. Potholes 6. Edge defects

55 Pavement Cracks Cracks fissures resulting from partial or complete fractures of the pavement surface Variety of patterns from isolated to interconnected over entire surface Detrimental effects of cracks: 1. Loss of water proofing 2. Loss of load spreading ability 3. Pumping and loss of fines from road base 4. Loss of riding quality 5. Loss of appearance

56 Pavement Cracks Possible causes of cracks Depression, Fatigue life of surfacing exceeded, Age embrittlement of surfacing, Reflection cracks from underlying layers, Shrinkage, Poor construction joint Probable treatments cut and patch, reconstruction, replace surfacing, crushed aggregate overlay, crack sealing, improve drainage and shoulder, widen pavement, strengthen shoulder, overlay with stiffer mix Types of cracks longitudinal, transverse, block, crocodile, edge, crescent shape

57 Surface Deformations Deformation takes place when surface undergo changes from its original profile (due to traffic, environment, inadequate control during construction) Influences riding quality and may reflect structural inadequacies, may lead to cracks Possible causes inadequate thickness, poor compaction, unstable premix, base or sub-base, volume change, settlement, lack of bond between bituminous layers, start-stop Probable treatments overlay or reconstruction, replace/recycle with stiffer mix, base/sub-base strengthening, improve subsoil drainage, shoulder improvement Major types rutting, corrugation, shoving, depression

58 Surface Defects Surface defects cover loss of surfacing materials and surface micro/macro texture Have significant influence on serviceability, safety (skid resistance and maneuverability), and riding quality. If not corrected may lead to loss of pavement structural integrity Possible causes excessive/lack of binder content, excessive/lack of coating, paving over flushed surface, poor adhesion between aggregate and binder, inadequate compaction, low PSV, seepage of water tru surface, adhesion of binder to vehicle tyres Probable treatments apply hot sand, thin bituminous overlay, use stiffer mix, mill and re-lay upper layer, replace WC, reconstruction of weak layers Major types bleeding, polishing, raveling, delamination

59 Patch & Pothole Patch repaired section where a portion of pavement has been removed and replaced Extend and frequency as indicator of structural adequacy Defects can occur within a patch or patch higher/lower than pavement surface Pothole bowl shape cavity in the pavement from loss of WC and BC Produced when traffic breaches small pieces of pavement allowing water to enter > disintegrate, collected water accelerates disintegration Possible causes loss of surface, moisture entry tru cracks, load associated base disintegration Probable treatments cut and patch, base reconstruction

60 Edge defects Occur along interface of pavement and shoulder, most significant if shoulder unsealed Detrimental effects reduction of pavement width, loss of riding quality and maybe loss of control, channeling water erodes shoulder, entry of water into base Possible causes inadequate width/edge support, poor alignment, edge drop-off,loss of adhesion to base, shoulder material of low resistance to abrasion and erosion, resurface pavement w/o resurface shoulder Probable treatments widening, re-alignment, strengthen and leveled shoulder, cut and patch, replace shoulder material Types of edge defects edge drop-offs, edge breaks

61 End of SAM4814 Highway Maaf atas segala kesilapan dan kesalahan saya, sama ada disedari atau pun tidak Good luck with what ever you are & will be doing See U FINAL nanti Feel free to drop by if U have any question or just 1 2 chat with me