8/2/2011 Construction Project
Management, NAC, Hyd
-- A. RameshA. Ramesh M.TECH, MITE (M.TECH, MITE (Ph.dPh.d))
Sr. Asst. ...
8/2/2011 Construction Project
Management, NAC, Hyd
OVERVIEWOVERVIEW
• Introduction on Pavements
• Construction of WBM
• Co...
8/2/2011 Construction Project
Management, NAC, Hyd
TYPES OF PAVEMENTSTYPES OF PAVEMENTS
•Un Surfaced
–Earthen roads
–Grave...
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Management, NAC, Hyd
• Flexible Pavements
– Earthen Roads
– Gravel Roads
– Bituminous Roads
...
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GRAVEL ROADSGRAVEL ROADS
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BITUMINOUS PAVEMENTBITUMINOUS PAVEMENT
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CROSS SECTION OFCROSS SECTION OF FLEXIBLEFLEXIBLE
PAVEMENTPAVEMENT
Wear...
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Prime coat over granular base/ Tack coat
Bituminous macadam (BM)
Bitumi...
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Sub-base non-bituminous)
• Granular sub-base (GSB)
• Lime treated soil ...
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Base Courses ( bituminous)
• Bituminous macadam (BM)
• Bituminous penet...
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• Surface Dressing (SD)
• Open graded Premix surfacing
• Closed Graded ...
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Treatment in between two layers
• Prime coat over granular base
• Tack ...
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CONSTRUCTION OF WBM PAVEMENT
8/2/2011 Construction Project
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SubSub--base/base/ basesbases
(non(non--bituminous)bituminous)
• Water ...
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Management, NAC, Hyd
• Embankment Construction – if required
• Subgrade Construction
• Subgr...
8/2/2011 Construction Project
Management, NAC, Hyd
• Embankment- refers to
a volume of earthen
material that is placed
and...
8/2/2011 Construction Project
Management, NAC, Hyd
• EMBANKMENT
• Soil survey and identification of borrow areas
– Height ...
8/2/2011 Construction Project
Management, NAC, Hyd
•For identification: Borrow soil sample to be brought
at different dept...
8/2/2011 Construction Project
Management, NAC, Hyd
Size of coarse material : <75 mm (embankment) and
<50 mm when placed in...
8/2/2011 Construction Project
Management, NAC, Hyd
General Requirements
Min 95embankment
Min 97.Subgrade and earthen shoul...
8/2/2011 Construction Project
Management, NAC, Hyd
To achieve max. dry density: as required
Diff. Between subgrade top and...
8/2/2011 Construction Project
Management, NAC, Hyd
Rolling
• motor grader for spreading
• Roller of 8-10T capacity vibrato...
8/2/2011 Construction Project
Management, NAC, Hyd
Vibratory roller
8/2/2011 Construction Project
Management, NAC, Hyd
Vibratory roller
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Management, NAC, Hyd
Sheep foot roller
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Management, NAC, Hyd
Compaction requirements for Embankment and Subgrade
Type of work/materi...
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Management, NAC, Hyd
Specification for compaction of embankment
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Management, NAC, Hyd
Compaction
Process by which soil particles are artificially
rearranged ...
8/2/2011 Construction Project
Management, NAC, Hyd
Compaction (dry unit weight)- increases the strength
characteristics of...
8/2/2011 Construction Project
Management, NAC, Hyd
8/2/2011 Construction Project
Management, NAC, Hyd
Factors Affecting Compaction
1. Moisture Content
2. Soil Type
3. Effect...
8/2/2011 Construction Project
Management, NAC, Hyd
Moisture Content
As the moisture content increases with the same
compac...
8/2/2011 Construction Project
Management, NAC, Hyd
Soil Type
Grain size, the shape of the soil grains, the
amount and type...
8/2/2011 Construction Project
Management, NAC, Hyd
Effects of Soil Types on CompactionEffects of Soil Types on Compaction
...
8/2/2011 Construction Project
Management, NAC, Hyd
Effect of Compaction Effort: Amount of Compactive
Effort
Compaction ene...
8/2/2011 Construction Project
Management, NAC, Hyd
Effect of compaction energy on the compaction of a sandy
clay.
8/2/2011 Construction Project
Management, NAC, Hyd
8/2/2011 Construction Project
Management, NAC, Hyd
test
1
2
3
2: Standard Proctor test 3: Modified Proctor test
Various ty...
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Management, NAC, Hyd
Test EquipmentTest Equipment
Standard Proctor test equipment
Das, 1998
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Management, NAC, Hyd
Variables of CompactionVariables of Compaction
Proctor established that...
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Management, NAC, Hyd
Modified Proctor
Modified proctor Standard Proctor
No of Blows 55 55
No...
8/2/2011 Construction Project
Management, NAC, Hyd
General Compaction MethodsGeneral Compaction Methods
Coarse-grained soi...
8/2/2011 Construction Project
Management, NAC, Hyd
Subgrade Construction
• Preparation of subgrade- all operations before ...
8/2/2011 Construction Project
Management, NAC, Hyd
Stabilization with lime and sand
Stabilization with coal ash
Stabilizat...
8/2/2011 Construction Project
Management, NAC, Hyd
Sub-base work with Gravel and Sand admixture
8/2/2011 Construction Project
Management, NAC, Hyd
Step: 2
Construction of Sub-base/ bases (non-bituminous)
Water Bound Ma...
8/2/2011 Construction Project
Management, NAC, Hyd
Compaction equipment
Smooth wheeled, vibratory, pneumatic, sheep foot
r...
8/2/2011 Construction Project
Management, NAC, Hyd
Nuclear density gauge
Gamma rays- in to soil and detector receive the r...
8/2/2011 Construction Project
Management, NAC, Hyd
Sand replacement method for field density
8/2/2011 Construction Project
Management, NAC, Hyd
WBM- Materials used: Coarse aggregates (CA) :
crushed/broken stone, cru...
8/2/2011 Construction Project
Management, NAC, Hyd
Aggregate grading requirements: 3 grades (I, II and III)
WBM Gradation
...
8/2/2011 Construction Project
Management, NAC, Hyd
Screenings: To fill voids in the CA. Same material as CA/non-
plastic m...
8/2/2011 Construction Project
Management, NAC, Hyd
Binding material: Filler material to prevent raveling.
PI< 6
CONSTRUCTI...
8/2/2011 Construction Project
Management, NAC, Hyd
Lateral Confinement of Aggregates
• Construct side shoulders in advance...
8/2/2011 Construction Project
Management, NAC, Hyd
Rolling
• Immediately after spreading, compacted to the full
width by r...
8/2/2011 Construction Project
Management, NAC, Hyd
• Rolling not done when the subgrade is soft or
yielding or when rollin...
8/2/2011 Construction Project
Management, NAC, Hyd
Application of Screenings
• Screenings shall be applied gradually over ...
8/2/2011 Construction Project
Management, NAC, Hyd
Sprinkling and Grouting
• Copiously sprinkling with water, swept and ro...
8/2/2011 Construction Project
Management, NAC, Hyd
Application of Binding Material
• Suitable binding material applied at ...
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Management, NAC, Hyd
Setting and Drying
• Allowed to dry over night
• Next morning uneven sp...
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Management, NAC, Hyd
WBM- rural road
8/2/2011 Construction Project
Management, NAC, Hyd
Wet Mix Macadam (WMM)
WMM- : This work shall consists of laying and com...
8/2/2011 Construction Project
Management, NAC, Hyd
Aggregate grading requirements: I grade
IS sieve % weight passing
53 10...
8/2/2011 Construction Project
Management, NAC, Hyd
Construction steps:
· Preparation of foundation: As per specification w...
8/2/2011 Construction Project
Management, NAC, Hyd
• Compaction: uniformly compacted to the full
depth with suitable rolle...
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Management, NAC, Hyd
Construction of Bituminous layers
8/2/2011 Construction Project
Management, NAC, Hyd
References:
MORTH- Specifications for roads and bridge works, 2004
Cons...
8/2/2011 Construction Project
Management, NAC, Hyd
Some of the bituminous layers
Prime coat over granular
base
Tack coat
B...
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Management, NAC, Hyd
To plug the capillary voids
To coat and bond loose materials on the
sur...
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Depends on porosity
Depends on type of bitumen viscosity
MORTH specifie...
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Self heating arrangement
Suitable pumping
Compressors
Spraying biers wi...
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Application of single coat of low viscosity
bitumen on a porous granula...
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Purpose of Tack Coat:
To ensure a bond between the new
construction and...
8/2/2011 Construction Project
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Single coat low viscosity bituminous binder
To provide bond between old...
8/2/2011 Construction Project
Management, NAC, Hyd
Weather & seasonal limitations
bituminous primer should not be applied ...
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Shall be clean and free from dust, dirt
and any extraeous material
Surf...
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Management, NAC, Hyd
Typical
Application
Application of Tack Coat
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Application of Tack Coat
Proper
Coverage
8/2/2011 Construction Project
Management, NAC, Hyd
WRONG PRACTICE OF TACK COATWRONG PRACTICE OF TACK COAT
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Management, NAC, Hyd
Bituminous Concrete pavement construction
8/2/2011 Construction Project
Management, NAC, Hyd
Bituminous ConcreteBituminous Concrete
• Used for wearing / profile cor...
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Management, NAC, Hyd
FAILURES IN PAVEMENTFAILURES IN PAVEMENT
• Major are two in category
– ...
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FATIGUEFATIGUE
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Fatigue crackingFatigue cracking
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RUTTINGRUTTING
Rutting in wheel paths
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Reflection cracking at PCCReflection cracking at PCC
JointsJoints
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Management, NAC, Hyd
• Subgrade - Core Cutter Method
or Sand Replacement
Method
• Overlays -...
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SAND REPLACEMENTSAND REPLACEMENT
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BITUMEN EXTRACTIONBITUMEN EXTRACTION
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FIFTH TOWED WHEEL BUMPFIFTH TOWED WHEEL BUMP
INTEGRATORINTEGRATOR
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Road work is under progress underRoad work is under progress under
PMGS...
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Strengthening of rural infrastructure through construction of roads und...
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Connectivity with urban areas through road constructed under PMGSY
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CLOSING REMARKSCLOSING REMARKS
All roads need maintenance
Several types...
8/2/2011 Construction Project
Management, NAC, Hyd
QUESTIONS AND DISCUSSIONQUESTIONS AND DISCUSSION
8/2/2011 Construction Project
Management, NAC, Hyd
of 96

Nac pavements constructions

Published on: Mar 3, 2016
Source: www.slideshare.net


Transcripts - Nac pavements constructions

  • 1. 8/2/2011 Construction Project Management, NAC, Hyd -- A. RameshA. Ramesh M.TECH, MITE (M.TECH, MITE (Ph.dPh.d)) Sr. Asst. Prof, CED,Sr. Asst. Prof, CED, VNR VJIET, HYDVNR VJIET, HYD PAVEMENTPAVEMENT CONSTRUCTION
  • 2. 8/2/2011 Construction Project Management, NAC, Hyd OVERVIEWOVERVIEW • Introduction on Pavements • Construction of WBM • Construction of WMM • Construction of Bituminous Roads • Failures in Aspects • Closing Remarks
  • 3. 8/2/2011 Construction Project Management, NAC, Hyd TYPES OF PAVEMENTSTYPES OF PAVEMENTS •Un Surfaced –Earthen roads –Gravel roads •Surfaced –Bituminous Road –Cement Concrete Road •Un Conventional –Block Pavement
  • 4. 8/2/2011 Construction Project Management, NAC, Hyd • Flexible Pavements – Earthen Roads – Gravel Roads – Bituminous Roads • Rigid Pavements – Reinforced Concrete – Plane Concrete Roads FURTHER CLASSIFICATIONFURTHER CLASSIFICATION OF PAVEMENTSOF PAVEMENTS
  • 5. 8/2/2011 Construction Project Management, NAC, Hyd GRAVEL ROADSGRAVEL ROADS
  • 6. 8/2/2011 Construction Project Management, NAC, Hyd BITUMINOUS PAVEMENTBITUMINOUS PAVEMENT
  • 7. 8/2/2011 Construction Project Management, NAC, Hyd CROSS SECTION OFCROSS SECTION OF FLEXIBLEFLEXIBLE PAVEMENTPAVEMENT Wearing course Surface course Base course Sub-base course (GSB) Drainage Layer Subgrade
  • 8. 8/2/2011 Construction Project Management, NAC, Hyd Prime coat over granular base/ Tack coat Bituminous macadam (BM) Bituminous penetration macadam Built-up Spray Grout Dense Bituminous Macadam (DBM) Semi-dense Bituminous Concrete (SDBC) Bituminous Concrete (BC) Surface Dressing (SD) Open graded Premix surfacing Closed Graded Premix Surfacing Seal Coat Mastic Asphalt Seal Fog Spray BASES AND SURFACE COURSES
  • 9. 8/2/2011 Construction Project Management, NAC, Hyd Sub-base non-bituminous) • Granular sub-base (GSB) • Lime treated soil for improved subbase /subgrade Base Course ( non-bituminous) • Cement Treated soil sub-base/base • Water Bound Macadam (WBM) base • Crushed cement concrete sub-base/base • Wet Mix Macadam (WMM) base • Crusher run macadam base
  • 10. 8/2/2011 Construction Project Management, NAC, Hyd Base Courses ( bituminous) • Bituminous macadam (BM) • Bituminous penetration macadam • Built-up Spray Grout • Dense Bituminous Macadam (DBM) • Semi-dense Bituminous Concrete (SDBC)
  • 11. 8/2/2011 Construction Project Management, NAC, Hyd • Surface Dressing (SD) • Open graded Premix surfacing • Closed Graded Premix Surfacing • Seal Coat • Mastic Asphalt • Chip Seal • Fog Spray Surface Course (bituminous) for high volume roads •Bituminous Concrete (BC) Wearing Course
  • 12. 8/2/2011 Construction Project Management, NAC, Hyd Treatment in between two layers • Prime coat over granular base • Tack coat
  • 13. 8/2/2011 Construction Project Management, NAC, Hyd CONSTRUCTION OF WBM PAVEMENT
  • 14. 8/2/2011 Construction Project Management, NAC, Hyd SubSub--base/base/ basesbases (non(non--bituminous)bituminous) • Water Bound Macadam (WBM): work shall consists of clean, crushed aggregates mechanically interlocked by rolling and bonding together with screening, binding material where necessary and laid on a properly prepared subgrade/sub-base/existing pavement.
  • 15. 8/2/2011 Construction Project Management, NAC, Hyd • Embankment Construction – if required • Subgrade Construction • Subgrade: Top 500 mm compacted thickness of native/borrow material prepared as per standard conditions Step:1
  • 16. 8/2/2011 Construction Project Management, NAC, Hyd • Embankment- refers to a volume of earthen material that is placed and compacted for the purpose of raising the grade of a roadway (or railway) above the level of the existing surrounding ground surface. • A fill refers to a volume of earthen material that is placed and compacted for the purpose of filling in a hole or depression. material. embankment
  • 17. 8/2/2011 Construction Project Management, NAC, Hyd • EMBANKMENT • Soil survey and identification of borrow areas – Height of embankment : 0.6m/1m above the H.F.L. or ground. – Rolling by 150 to 300 mm compacted thickness – Materials free of logs, stumps, roots, rubbish or any other ingredients , LL<70 and PI<45 – Highly expansive clays only at the bottom of the embankment, no such material placed nor permitted to remain in the top 500mm
  • 18. 8/2/2011 Construction Project Management, NAC, Hyd •For identification: Borrow soil sample to be brought at different depths. •All clods broken into fine earth(<75 mm size) and spread confining to crown shape •Select Moisture content that uses least effort for compaction and uniform sprinkling •Commencement of rolling using 8-10 t roller •Earth work: Loose thickness of soil layer should not exceed 20cm EMBANKMENT CONSTRUCTION
  • 19. 8/2/2011 Construction Project Management, NAC, Hyd Size of coarse material : <75 mm (embankment) and <50 mm when placed in the subgrade Density requirements Type of work Max. lab dry unit weight Embankment (upto 3m) >15.2 kN/ cu.m Embankment >3 m >16.0 kN/cu.m Subgrade and earthen shoulders > 17.5 kN/cu.m
  • 20. 8/2/2011 Construction Project Management, NAC, Hyd General Requirements Min 95embankment Min 97.Subgrade and earthen shoulders Relative compaction of max.lab dry density Type of work Construction Setting out- Limits of embankment/ subgrade to be marked- pegs Dewatering- If water is stagnant and possible to remove, remove Stripping and Storing topsoil- 150 mm top soil- stripped and stockpiled Compacting ground supporting embankment/subgrade-Original ground to be levelled – scarified, mixed with water and compact
  • 21. 8/2/2011 Construction Project Management, NAC, Hyd To achieve max. dry density: as required Diff. Between subgrade top and ground level< 500 mm and ground does not have 97 % relative compaction with respect to dry density, ground to be loosened upto 500 mm below subgrade and watered and compacted in layers Spreading materials in layers and bringing to appropriate moisture content -to be spread in 200 mm compacted thickness- compacted and finished with motor grader. -Moisture content to be checked prior to compaction. If required to be sprinkled by sprinkler capable of spreading uniform rate
  • 22. 8/2/2011 Construction Project Management, NAC, Hyd Rolling • motor grader for spreading • Roller of 8-10T capacity vibratory roller • Rolling begins from edges with the roller running forward and backward • Progress gradually from the edges to centre overlapping uniformly each preceding rear wheel track by one half width • Rolling continue until the road metal thoroughly keyed with no creeping of metal ahead of the roller • Slight sprinkling of water •Rolling not done when the subgrade is soft or yielding or when rolling causes a wave like motion in the subbase or subgrade • Checked transversely by template for camber • Irregularities corrected
  • 23. 8/2/2011 Construction Project Management, NAC, Hyd Vibratory roller
  • 24. 8/2/2011 Construction Project Management, NAC, Hyd Vibratory roller
  • 25. 8/2/2011 Construction Project Management, NAC, Hyd Sheep foot roller
  • 26. 8/2/2011 Construction Project Management, NAC, Hyd Compaction requirements for Embankment and Subgrade Type of work/material Relative compaction as % max. lab dry density 1. Subgrade & earthen shoulders Not less than 97 2. Embankment Not less than 95 3. Expansive clays a. Subgrade & 500 mm below subgrade b. Remaining portion of embankment Not less than 90 Source: Specifications for Roadworks and ridges, MORTH, 2004
  • 27. 8/2/2011 Construction Project Management, NAC, Hyd Specification for compaction of embankment
  • 28. 8/2/2011 Construction Project Management, NAC, Hyd Compaction Process by which soil particles are artificially rearranged and packed together into closer state of contact by mechanical means- to decrease porosity/voids- increase in density Consolidation- gradual process of volume reduction by means of sustained loading
  • 29. 8/2/2011 Construction Project Management, NAC, Hyd Compaction (dry unit weight)- increases the strength characteristics of soils, thereby increasing the bearing capacity of “foundations” constructed over them. Maximum dry density - density at which the volume of air at a specific energy application is kept to a minimum, implying that the soil particles are rearranged to give a minimum volume of air at the compaction energy. Soil compaction results in · Higher Strength · Reduced Settlement · Reduced Permeability
  • 30. 8/2/2011 Construction Project Management, NAC, Hyd
  • 31. 8/2/2011 Construction Project Management, NAC, Hyd Factors Affecting Compaction 1. Moisture Content 2. Soil Type 3. Effect of Compaction Effort 3.1 Amount of Effort 3.2 Nature of Effort: Load Duration and Area of Contact
  • 32. 8/2/2011 Construction Project Management, NAC, Hyd Moisture Content As the moisture content increases with the same compactive effort, the weight of the soil solids in a unit volume gradually increases. Beyond a certain moisture content, any increase in the moisture content tends to reduce the dry unit weight because water takes up the spaces that would have been occupied by the solid particles. Moisture content at which the maximum dry unit weight is attained - optimum moisture content (OMC), when the degree of saturation equals 100%.
  • 33. 8/2/2011 Construction Project Management, NAC, Hyd Soil Type Grain size, the shape of the soil grains, the amount and type of clay minerals present and the specific gravity of soil solids, has a great influence on the maximum dry unit weight and optimum moisture content. Well graded course grain soils attains higher density and lower OMC compared to fine grain grained soils.
  • 34. 8/2/2011 Construction Project Management, NAC, Hyd Effects of Soil Types on CompactionEffects of Soil Types on Compaction •The soil type-that is, grain-size distribution, shape of the soil grains, specific gravity of soil solids, and amount and type of clay minerals present. Holtz and Kovacs, 1981; Das, 1998
  • 35. 8/2/2011 Construction Project Management, NAC, Hyd Effect of Compaction Effort: Amount of Compactive Effort Compaction energy per unit volume (E) used for the standard proctor test is described as follows: E = [ (No of blows/layer) x (No of layers) x (weight of hammer) x (drop height of hammer) ] / Volume of the mould. If the compactive effort per unit volume is altered, the moisture unit weight curve is also altered. As the compaction effort increases, the maximum dry unit weight of compaction also increases. In addition, the increase in compaction effort also causes the optimum moisture content to decrease to some extent.
  • 36. 8/2/2011 Construction Project Management, NAC, Hyd Effect of compaction energy on the compaction of a sandy clay.
  • 37. 8/2/2011 Construction Project Management, NAC, Hyd
  • 38. 8/2/2011 Construction Project Management, NAC, Hyd test 1 2 3 2: Standard Proctor test 3: Modified Proctor test Various types of compactionVarious types of compaction
  • 39. 8/2/2011 Construction Project Management, NAC, Hyd Test EquipmentTest Equipment Standard Proctor test equipment Das, 1998
  • 40. 8/2/2011 Construction Project Management, NAC, Hyd Variables of CompactionVariables of Compaction Proctor established that compaction is a function of four variables: (1)Dry density (ρd) or dry unit weight γd. (2)Water content w (3)Compactive effort (energy E) (4)Soil type (gradation, presence of clay minerals, etc.) )ft/lbft375,12(m/kJ7.592 m10944.0 )layer/blows25)(layers3)(m3048.0)(s/m81.9(kg495.2 E 33 33 2 ⋅ − = × = Volume of mold Number of blows per layer Number of layers Weight of hammer Height of drop of hammer × × × E = For standard Proctor test
  • 41. 8/2/2011 Construction Project Management, NAC, Hyd Modified Proctor Modified proctor Standard Proctor No of Blows 55 55 No of Layers 5 3 Hammer weight 4.536kg 2.495kg Drop Height 457.2mm 304.8 mm Volume of mould 2280cm3 2280 cm3
  • 42. 8/2/2011 Construction Project Management, NAC, Hyd General Compaction MethodsGeneral Compaction Methods Coarse-grained soils Fine-grained soils •Hand-operated vibration plates •Motorized vibratory rollers •Rubber-tired equipment •Free-falling weight; dynamic compaction (low frequency vibration, 4~10 Hz) •Falling weight and hammers •Kneading compactors •Static loading and press •Hand-operated tampers •Sheepsfoot rollers •Rubber-tired rollers LaboratoryField Vibration •Vibrating hammer (BS) (Holtz and Kovacs, 1981; Head, 1992) Kneading
  • 43. 8/2/2011 Construction Project Management, NAC, Hyd Subgrade Construction • Preparation of subgrade- all operations before pavement structure is laid • Subgrade- Top 300mm of embankment • Earth spread to a crown shape in straight reaches and bank profile in curve reaches • Compacted to a 100% standard Proctor density • Capping layer of 100 mm with Soil with CBR: 10 when clay is used as subgrade material • Camber checking- camber board
  • 44. 8/2/2011 Construction Project Management, NAC, Hyd Stabilization with lime and sand Stabilization with coal ash Stabilization with cement etc Subgrade with stablized earth
  • 45. 8/2/2011 Construction Project Management, NAC, Hyd Sub-base work with Gravel and Sand admixture
  • 46. 8/2/2011 Construction Project Management, NAC, Hyd Step: 2 Construction of Sub-base/ bases (non-bituminous) Water Bound Macadam (WBM): This work shall consists of clean, crushed aggregates mechanically interlocked by rolling and bonding together with screening, binding material where necessary and laid on a properly prepared subgrade/sub-base/existing pavement.
  • 47. 8/2/2011 Construction Project Management, NAC, Hyd Compaction equipment Smooth wheeled, vibratory, pneumatic, sheep foot rollers Field Density measurement Density measurement- Nuclear density gauge (gamma rays) sand replacement method
  • 48. 8/2/2011 Construction Project Management, NAC, Hyd Nuclear density gauge Gamma rays- in to soil and detector receive the rays back and density can be calculated. Neutron radiation- emitted- neutrons lose energy due to collision with hydrogen atoms in soil, detector measures the neutrons that pass through soil and thus moisture content
  • 49. 8/2/2011 Construction Project Management, NAC, Hyd Sand replacement method for field density
  • 50. 8/2/2011 Construction Project Management, NAC, Hyd WBM- Materials used: Coarse aggregates (CA) : crushed/broken stone, crushed slag, over burnt brick/ laterite..etc Specifications of crushed/ broken stone Test Test Method Requirements Los Angeles IS:2386(part IV) 40 % (max) Impact IS: 2386(part IV) 30 % (max) Combined flakiness+ elongation Index IS:2386(part I) 30 % (max)
  • 51. 8/2/2011 Construction Project Management, NAC, Hyd Aggregate grading requirements: 3 grades (I, II and III) WBM Gradation Grading No Size range IS sieve % weight passing 125 100 90 90-100 63 25-60 45 0-15 1 (100 mm) 90 to 45 mm 22.4 0-5 90 100 63 90-100 53 25-75 45 0-15 2 (75 mm) 63 to 45 mm 22.4 0-5 63 100 53 95-100 45 65-90 22.4 0-10 3 (75 mm) 53 to 22.4 mm 11.2 0-5
  • 52. 8/2/2011 Construction Project Management, NAC, Hyd Screenings: To fill voids in the CA. Same material as CA/non- plastic material such as moorum/gravel (passing 75 micron does not exceed 10%) GradingNo Sizerange ISsieve %weightpassing 13.2 100 11.2 95-100 5.6 15-35A 13.2mm 180micron 0-10 11.2 100 5.6 90-100 B 11.2mm 180micron 15-35
  • 53. 8/2/2011 Construction Project Management, NAC, Hyd Binding material: Filler material to prevent raveling. PI< 6 CONSTRUCTION STEPS Preparation of Foundation Existing unsurfaced road • Surface scarified and reshaped to the required grade, camber and shape • Weak places strengthened; corrugations removed and depressions, pot holes etc. made good with suitable materials •Existing black topped surface • Furrows 50mm x 50mm at 1m intervals 45 0 to the central line
  • 54. 8/2/2011 Construction Project Management, NAC, Hyd Lateral Confinement of Aggregates • Construct side shoulders in advance • Inside edges may be trimmed vertical • Included area cleaned off all spilled materials Spreading of Aggregates • Uniformly and evenly spread • Twisting motion to avoid segregation • Proper profile by using templates • Surface of the aggregate spread trued up and all high or low spots remedied by removing or adding aggregate
  • 55. 8/2/2011 Construction Project Management, NAC, Hyd Rolling • Immediately after spreading, compacted to the full width by rolling with either a three wheel power roller of 8- 10T capacity or an equivalent vibratory roller • Rolling begins from edges with the roller running forward and backward • Adding screenings simultaneously until edges compacted • Progress gradually from the edges to centre overlapping uniformly each preceding rear wheel track by one half width • Rolling continue until the road metal thoroughly keyed with no creeping of metal ahead of the roller • Slight sprinkling of water
  • 56. 8/2/2011 Construction Project Management, NAC, Hyd • Rolling not done when the subgrade is soft or yielding or when rolling causes a wave like motion in the subbase or subgrade • Checked transversely by template for camber • Irregularities corrected • In no case use of screenings to make up depressions permitted CONSTRUCTION STEPS- WBM
  • 57. 8/2/2011 Construction Project Management, NAC, Hyd Application of Screenings • Screenings shall be applied gradually over the surface to completely fill the interstices • Screenings shall not be dumped in piles • Spread uniformly in successive thin layers • Spreading motion of the hand, shovels or a mechanical spreader • Brooming of screening to fill
  • 58. 8/2/2011 Construction Project Management, NAC, Hyd Sprinkling and Grouting • Copiously sprinkling with water, swept and rolled • Sprinkling, sweeping and rolling operation continued and additional screenings applied • Till a grout is formed of screenings and water that will fill all voids and form a wave of grout ahead of the wheels of the roller
  • 59. 8/2/2011 Construction Project Management, NAC, Hyd Application of Binding Material • Suitable binding material applied at a uniform and slow rate in two or more successive thin layers • Copiously sprinkled with water and resulting slurry swept in with hand brooms or mechanical brooms so as to fill the voids properly • Surface then rolled by a 8-10 tonne roller • Spreading of binding material, sprinkling of water, sweeping with brooms • Rolling continue until the slurry that is formed forms a wave ahead of wheels of moving roller
  • 60. 8/2/2011 Construction Project Management, NAC, Hyd Setting and Drying • Allowed to dry over night • Next morning uneven spot filled with screening or binding material sprinkled with water if necessary • Rolled • No traffic allowed on the road until this has set
  • 61. 8/2/2011 Construction Project Management, NAC, Hyd WBM- rural road
  • 62. 8/2/2011 Construction Project Management, NAC, Hyd Wet Mix Macadam (WMM) WMM- : This work shall consists of laying and compacting clean, crushed, graded aggregate and granular material, premixed with water to a dense mass on properly prepared subgrade/sub-base/existing pavement (75 to 200 mm thickness). Materials used: Coarse aggregates (CA) : crushed/broken stone, Specifications of crushed/ broken stone
  • 63. 8/2/2011 Construction Project Management, NAC, Hyd Aggregate grading requirements: I grade IS sieve % weight passing 53 100 45 95-100 26.5 - 22.4 60-80 11.2 40-60 4.75 25-40 2.36 15-30 600 micron 8-22 75 micron 0-8
  • 64. 8/2/2011 Construction Project Management, NAC, Hyd Construction steps: · Preparation of foundation: As per specification with required camber. Irregular surface to rectify by profile corrective course · Preparation of lateral confinement of aggregates: laying adjoining shoulder material. · Preparation of mix: Approved mixing plant; OMC as per IS:2720 (part:8) after replacing the aggregate fraction retained on 22.4 mm sieve with 22.4-4.75 mm. No segregation is allowed. Spreading of mix: uniform spreading- paver finisher (loading hopper and suitable distribution mechanism, tamping and vibrating arrangement for initial compaction) /motor grader( blades have hydraulic control for adjustments)
  • 65. 8/2/2011 Construction Project Management, NAC, Hyd • Compaction: uniformly compacted to the full depth with suitable roller. 100 mm thick- smooth wheel roller (80-100 kN); 200 mm thick – vibratory roller (80-100kN-static weight); speed-5kmph. Edge to centre- uniform rolling. 98% max. dry density. Irregularies during rolling where 12 mm depth- surface should be loosed and premixed material is added and roller again. Setting and drying: 24 hours and allowed for traffic
  • 66. 8/2/2011 Construction Project Management, NAC, Hyd Construction of Bituminous layers
  • 67. 8/2/2011 Construction Project Management, NAC, Hyd References: MORTH- Specifications for roads and bridge works, 2004 Construction of Hot Mix Asphalt Pavements, Ms series 22, Asphalt Institute
  • 68. 8/2/2011 Construction Project Management, NAC, Hyd Some of the bituminous layers Prime coat over granular base Tack coat Bituminous macadam (BM) Bituminous penetration macadam Built-up Spray Grout Dense Bituminous Macadam (DBM) Semi-dense Bituminous Concrete (SDBC) Bituminous Concrete (BC) Surface Dressing (SD) Open graded Premix surfacing Closed Graded Premix Surfacing Mastic Asphalt Fog Spray Seal Coat
  • 69. 8/2/2011 Construction Project Management, NAC, Hyd To plug the capillary voids To coat and bond loose materials on the surface To harden or toughen the surface To promote adhesion between granular and the bituminous layer PURPOSE OF PRIMING
  • 70. 8/2/2011 Construction Project Management, NAC, Hyd Depends on porosity Depends on type of bitumen viscosity MORTH specifies emulsion (IS8887) Sub zero temperature cutback (IS217) Materials
  • 71. 8/2/2011 Construction Project Management, NAC, Hyd Self heating arrangement Suitable pumping Compressors Spraying biers with nozzles Speed of the vechicle Opening of nozzle EQUIPMENT
  • 72. 8/2/2011 Construction Project Management, NAC, Hyd Application of single coat of low viscosity bitumen on a porous granular surface Prime Coat
  • 73. 8/2/2011 Construction Project Management, NAC, Hyd Purpose of Tack Coat: To ensure a bond between the new construction and the old surface Use of Cutback: It should be restricted for sites at subzero temperatures or for emergency applications TACK COAT
  • 74. 8/2/2011 Construction Project Management, NAC, Hyd Single coat low viscosity bituminous binder To provide bond between old & new surface • Materials • Emulsions → (IS – 8887: 2004) • Cutback → (IS – 217) (in sub-zero temperature)
  • 75. 8/2/2011 Construction Project Management, NAC, Hyd Weather & seasonal limitations bituminous primer should not be applied on a wet surface or during dust strom,weather is foggy rainy and windy when emulsion is used then surface can be damp but no standing water CONSTRUCTION
  • 76. 8/2/2011 Construction Project Management, NAC, Hyd Shall be clean and free from dust, dirt and any extraeous material Surface shall be swept clean with a mechanical and high pressure air jet PREPARATION OF BASE
  • 77. 8/2/2011 Construction Project Management, NAC, Hyd Typical Application Application of Tack Coat
  • 78. 8/2/2011 Construction Project Management, NAC, Hyd Application of Tack Coat Proper Coverage
  • 79. 8/2/2011 Construction Project Management, NAC, Hyd WRONG PRACTICE OF TACK COATWRONG PRACTICE OF TACK COAT
  • 80. 8/2/2011 Construction Project Management, NAC, Hyd Bituminous Concrete pavement construction
  • 81. 8/2/2011 Construction Project Management, NAC, Hyd Bituminous ConcreteBituminous Concrete • Used for wearing / profile corrective course • Work may require single or multiple layers • Thickness of a single layer is 25-100mm
  • 82. 8/2/2011 Construction Project Management, NAC, Hyd FAILURES IN PAVEMENTFAILURES IN PAVEMENT • Major are two in category – Fatigue • Fatigue cracking - series of interconnecting cracks on the pavement surface caused by repeated traffic loading • Fatigue occurs at places of bituminous layer – Rutting – It is called permanent deformation because it represents an accumulation of small amounts of unrecoverable deformations – under the channelized repeated wheel loads
  • 83. 8/2/2011 Construction Project Management, NAC, Hyd FATIGUEFATIGUE
  • 84. 8/2/2011 Construction Project Management, NAC, Hyd Fatigue crackingFatigue cracking
  • 85. 8/2/2011 Construction Project Management, NAC, Hyd RUTTINGRUTTING Rutting in wheel paths
  • 86. 8/2/2011 Construction Project Management, NAC, Hyd Reflection cracking at PCCReflection cracking at PCC JointsJoints
  • 87. 8/2/2011 Construction Project Management, NAC, Hyd • Subgrade - Core Cutter Method or Sand Replacement Method • Overlays - Benkelman Beam Deflection » In combination with roughness (5th towed wheel bump Integrator) FIELD EVALUATIONFIELD EVALUATION
  • 88. 8/2/2011 Construction Project Management, NAC, Hyd SAND REPLACEMENTSAND REPLACEMENT
  • 89. 8/2/2011 Construction Project Management, NAC, Hyd BITUMEN EXTRACTIONBITUMEN EXTRACTION
  • 90. 8/2/2011 Construction Project Management, NAC, Hyd FIFTH TOWED WHEEL BUMPFIFTH TOWED WHEEL BUMP INTEGRATORINTEGRATOR
  • 91. 8/2/2011 Construction Project Management, NAC, Hyd Road work is under progress underRoad work is under progress under PMGSYPMGSY
  • 92. 8/2/2011 Construction Project Management, NAC, Hyd Strengthening of rural infrastructure through construction of roads under PMGSY
  • 93. 8/2/2011 Construction Project Management, NAC, Hyd Connectivity with urban areas through road constructed under PMGSY
  • 94. 8/2/2011 Construction Project Management, NAC, Hyd CLOSING REMARKSCLOSING REMARKS All roads need maintenance Several types of maintenance works Timely maintenance measures avoids severe damage and saves lot of money Quality control measures during selection of pavement materials and construction always lessen the maintenance
  • 95. 8/2/2011 Construction Project Management, NAC, Hyd QUESTIONS AND DISCUSSIONQUESTIONS AND DISCUSSION
  • 96. 8/2/2011 Construction Project Management, NAC, Hyd

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