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April 11, 2023 Transportation Engineering Rahul Agrawal

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Guided by Dr. R. M. Damgir

Represented by Rahul Agrawal


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Pradhan Mantri Gram Sadak Yojana PMGSY

• Rural Road Connectivity is not only a key component of Rural Development by promoting access to economic and social services and thereby generating increased agricultural incomes and productive employment opportunities in India, it is also as a result, a key ingredient in ensuring sustainable poverty reduction. Notwithstanding the efforts made, over the years, at the State and Central levels, through different Programmes, about 40% of the Habitations in the country are still not connected by All-weather roads.

• It is well known that even where connectivity has been provided, the roads constructed are of such quality (due to poor construction or maintenance) that they cannot always be categorized as All-weather roads.

• With a view to redressing the situation, Government have launched the Pradhan Mantri Gram Sadak Yojana on 25th December, 2000 to provide all-weather access to unconnected habitations. The Pradhan Mantri Gram Sadak Yojana (PMGSY) is a 100% Centrally Sponsored Scheme. 50% of the Cess on High Speed Diesel (HSD) is earmarked for this Programme.


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• The primary objective of the PMGSY is to provide Connectivity, by way of an All-weather Road (with necessary culverts and cross-drainage structures, which is operable throughout the year), to the eligible unconnected Habitations in the rural areas, in such a way that all Unconnected Habitations with a population of 1000 persons and above are covered in three years (2000-2003) and all Unconnected Habitations with a population of 500 persons and above by the end of the Tenth Plan Period (2007). In respect of the Hill States (North-East, Sikkim, Himachal Pradesh, Jammu & Kashmir, Uttaranchal) and the Desert Areas (as identified in the Desert Development Programme) as well as the Tribal (Schedule V) areas, the objective would be to connect Habitations with a population of 250 persons and above.

• The PMGSY will permit the Upgradation (to prescribed standards) of the existing roads in those Districts where all the eligible Habitations of the designated population size (refer Para 2.1 above) have been provided all-weather road connectivity. However, it must be noted that Upgradation is not central to the Programme and cannot exceed 20% of the State’s allocation as long as eligible Unconnected Habitations in the State still exist. In Upgradation works, priority should be given to Through Routes of the Rural Core Network, which carry more traffic (see Para 3.7 below)

Pradhan Mantri Gram Sadak Yojana PMGSY


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Roman Road ConstructionBasic cross section


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• Jayakar Committee (1927)

• Central Road Fund (1929)

• Indian Roads Congress (IRC), 1934

• Central Road Research Institute (CRRI), 1950

• National Highway Act, 1956

• National Highway Authority of India (NHAI),1995

• National highway act ( 1956 )

• Second twenty year road plan ( 1961 )

• Highway Research board ( 1973 )

• National Transport Policy committee ( 1978 )

• Third twenty year road plan ( 1981 )

Institution for Highway Planning, Design and Implementation at Different Levels


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• Road development should be made a national interest since the provincial and local govt do not have financial and technical capacity for road development.

• Levy extra tax on petrol from road users to create the road development fund.

• To establish a semi-official ,technical institution to pool technical knowledge, sharing of ideas and to act as an advisory body.

• To create a national level institution to carry research , development works and consultation.

Jayakar Committee,1927


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Depending on weather• All weather roads• Fair weather roadsDepending the type of Carriage way• Paved roads• Unpaved roadsDepending upon the pavement surface• Surfaced roads • Un surfaced roadsBased on the Traffic Volume• Heavy • Medium • LightBased on Load or Tonnage• Class 1 or Class 2 etc or Class A , B etc Tonnes per dayBased on location and function ( Nagpur road plan ) NH, SH, MDR, ODR & VR

Classification of Highways


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• Rectangular or Block patterns• Radial or Star block pattern• Radial or Star Circular pattern• Radial or Star grid pattern• Hexagonal Pattern• Minimum travel Pattern

Road Patterns

• Expressways 200 Km

• National Highways 70,548 Km

• State Highways 1,31,899 Km

• Major District Roads 4,67,763 Km

• Rural and Other Roads 26,50,000 Km

Classification of Roadways


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Requirements: Short Easy Safe Economical

Factors controlling alignment :

1) Obligatory points

A. Obligatory points through which alignment is to pass ( bridge site, intermediate town , Mountain pass etc

B. Obligatory points through which alignment should not pass. 2) Traffic 3) Geometric design 4) Economics 5) Other considerations

Additional care in hill roadsStabilityDrainageGeometric standards of hill roadsResisting length

Factors Influencing Highway Alignment


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• Map Study (available topographic map)

• Reconnaissance Survey (identification of soil & on spot site inspection)

• Preliminary Survey (alternate alignment, comparison of alternate route & economic analysis)

• Location of Final Alignment (transfer of alignment, circular curve & transition curve & super elevation)

• Detailed Survey (Earth work quantities & other construction materials)

• Materials Survey (their collection & testing)

• Design (embankment & cut slopes, bridges & pavement layers)

• Earth Work ( highway cutting & drainage system)

• Pavement Construction (preparation of sub grade, sub base & surface course)

• Construction Control (quality control tests during different stages)

Steps in New Highways Project Works


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• Improvement of horizontal alignment design elements such as radius, super elevation, transition curve, clearance on inner side of the curve

• Improvement of vertical alignment design elements like steep gradients, changes in summit curve to increase sight distance, correction of undesirable undulations like humps and dips etc

• Raising level of portion of road which is subjected to flooding, submergence or water logging during monsoons

• Reconstruction of weak & narrow bridges & culverts & changes in water way at locations slightly away from existing site

• Construction of over bridges or under bridges at suitable locations across a railway line in place of level crossing or another roads to provide grade separate inter section

• Construction of bypass to avoid the road running through a town or city

• Defence requirements

Necessity of Re-alignment


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Alignment for hill roads• Minimum hair pin bends.• Bends should be located on stable and flat slopes.• Cross section for hair pin bends should be at intervals of 20-25m.

15 m on either side of centre line in straight alignment

• Avoid bends in valleys.• Survey for a width of ; 30m on sharp curves.

Geometric Design• Elements of design:

– Sight distance• The length of road ahead visible to drivers

– Stopping sight distance

– Passing sight distance

– Horizontal alignment• Super elevation rates (0.1 for rural areas, 0.06 for urban)

• Minimum radius

– Vertical alignment

– Pavement design

– Intersection and crossing design


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Cross Slope or Camber• It is the slope provided to the road surface in the transverse direction to drain off the rain water from the

road surface. Drainage and quick disposal of water from pavements surface by providing cross slope is considered important because

– To prevent entry of surface water into the sub grade soil through pavement, stability & life of pavement get affected if water enters in the sub grade and the soil gets soaked.

– To prevent entry of water into the bitumen layer and results in deterioration of pavement layers.• Shape of Camber

– Parabolic shape – Straight line camber– Combination of straight and parabolic shape

Class of road Width of carriage way

Single lane 3.75m

Two lanes, without raised Krebs 7.0m

Two lanes, with raised Krebs 7.5m

Intermediate carriage way 5.5m

Multi lane pavements 3.5m per lane


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Sight Distance• Sight distance available from a point is the actual distance along the road surface,

which driver from specific height above the carriage way has visibility of the stationary or moving object.

• Length of road visible ahead the driver at any instance.

• Sight distance are of – Stopping or absolute minimum sight distance

– Safe over taking or passing sight distance

– Safe sight distance for entering into uncontrolled intersections

Stopping Sight Distance– Minimum sight distance available on highway at any spot should be of

sufficient to length to stop vehicle traveling at design speed, safely without collision with any other obstruction.

– Depends on factor• Total reaction time of driver

• Speed of vehicle

• Efficiency of brakes

• Frictional resistance between road and tyre

• Gradient of the road


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PIEV Theory• According to this theory the total reaction time of the driver is split into four

parts viz. time by the driver for – Perception

• It is time required for the sensation received by the eyes or ears to be transmitted to the brain through nervous system & spinal cord.

– Intellection• It is time required for understanding the situation

– Emotion• It is time elapsed during emotional sensations and disturbance such as fear, anger or

other feelings.

– Volition • It is time taken for final action.

P V

I E

Reflex Action


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Analysis of Stopping Sight Distance

1. It is sum of – Lag distance (distance traveled by vehicle during total reaction time)

– Braking distance (distance traveled by vehicle after application of brakes)

2. Ld = v t meters

3. Bd = (V.V) / (2gf) meters

4. SSD = Ld + Bd= (v t ) + {(v v) / (2gf)} meters

= (0.278 v t ) + {(v v) / (254 f)} kmph

V = speed of vehicles

F = design coefficient of friction 0.4 to 0.35

G = acceleration due to gravity = 9.8 m/sec2


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Analysis of Overtaking Sight Distance

1. The minimum distance open to the vision of the driver of vehicle intending to overtake of slow vehicle ahead with the safety against traffic of opposite direction is known as Min. OSD or Safe OSD

2. Factor for min. OSD1. Overtaking speed of vehicle

2. Overtaken speed of vehicle

3. Speed of Vehicle coming from opposite side

4. Skill and reaction time of driver

5. Rate of acceleration of overtaking vehicle

6. Gradient of road3. (Justo Khanna Page no. 96)

OSD = 0.28 Vb t + 0.28 Vb T + 2s+ 0.28 V T

Vb = speed of over taking vehicle kmph

T = reaction time of driver = 2secs

V = speed of overtaking vehicle or design speed kmph

T = (14.4 s / A)^0.5 and Spacing = s = (0.2 Vb + 6 )


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Traffic Engineering

1. Traffic characteristics1. Road user characteristics

1. Physical characteristics

2. Mental characteristics

3. Environmental factors

2. Vehicular characteristics1. Static characteristic : Vehicle Dimension, Weight, Speed & Power of vehicle

2. Braking characteristic

2. Traffic studies and analysis1. Traffic volume studies

2. Origin and destination study

3. Parking study

3. Traffic operation-control and regulation

4. Planning and analysis

5. Geometric design

6. Administration and management


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PCU Passenger Car Unit

1. Different class of vehicles such as cars, vans, buses, trucks, auto rickshaw, motor cycles, pedal cycles, bullock carts, etc are found to use common roadway facilities without segregation on most of the roads in developing countries like India.

2. The flow of traffic with unrestrained mixing of different vehicle classes on the roadways forms the heterogeneous traffic flow or mixed traffic flow.

3. Different vehicle have different dimension like speed, length, acceleration.. and apart this it has different driver behavior..

4. Common practice of considering the passenger car as the standard vehicle unit to covert the other vehicle classes and this unit is called as PCU

5. PCU/lane or PCU/ hour or PCU/ kilometer length of lane..


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Regulatory signs

1. Regulatory or mandatory sign are meant to inform the road users of certain laws, regulations and prohibitions; the violation of these signs is legal offence.

2. Signs are classified as 1. Stop and Give-way sign

2. Prohibitory sign

3. No parking and no stopping sign

4. Speed limit and vehicle control sign

5. Restriction ends sign

6. Compulsory direction control and other sign

3. Informative signs 1. This sign are used to guide road users along routes, inform them of destination and

distance and provide with information to make travel easier, safe and pleasant.

2. Direction and place identification signs

3. Facility information signs

4. Other useful information signs

5. Parking signs

6. Flood gauge


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Traffic Signals

1. At intersection where there are a large number of crossing and right turn traffic, there is possibility of several accidents as there can’t be orderly movements.

2. Traffic signals are control devices which could alternately direct traffic to stop and proceed at intersections using Red, Yellow and Green.

3. Advantages1. Smooth movements and crossings

2. Reduce accidents

3. Safety

4. Control speed

4. Disadvantages1. Rear end collisions may increase

2. Improper design and location of signal may lead to violation of control systems

3. Failure of signal due to electric power.


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Highway Materials

1. Sub grade soil is an integral part of the road pavement structure as it provides the support to the pavement from beneath.

2. Desirable properties of soil as highway materials are1. Stability and incompressibility

2. Permanency of strength

3. Minimum changes in volume

4. Good drainage and Ease of compaction

3. Factor on which strength characteristics of soil depends on 1. Soil type and moisture content

2. Dry density

3. Internal structural of soil

4. Type and mode of stress application

4. Evaluation of soil1. Shear tests

2. Bearing tests

3. Penetration tests


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Direct Shear Tests

1. It is oldest shear tests.

2. Apparatus consists of box divided horizontally into two halves.

3. One halve is kept fixed and other half is free to move horizontally.

4. A vertical load is applied and horizontal movements are measured by dial gauges and horizontal force is noted from the providing ring dial.

5. Limitation : failure plane being predetermined horizontal plane, need not necessarily represent the imminent plane of failure.

6. The shearing stress and strain along this horizontal failure plane is seldom uniform.


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Plate Bearing Test

1. It is used to evaluate this supporting power of sub grade for use in pavement design by using relatively large diameter plates.

2. The PBT was originally devised to find the modulus of sub grade reaction in the Westergaard’s analysis for wheel load stress in cement concrete pavements.

3. Setup consists of a set of plates of diameter 75, 60, 45 & 30cm, a loading device consisting of jack and providing ring arrangement and reaction frame against ehich the jack give thrust to the plate.

4. A datum frame resting far from the loaded area and dial gauges from this frame are used to measure the settlement of the loaded plate.


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California Bearing Ratio (CBR) test• CBR was developed by the California Division

of Highways as a method of classifying and evaluating soil- sub grade and base course materials for flexible pavements.

• CBR is a measure of resistance of a material to penetration of standard plunger under controlled density and moisture conditions.

• CBR test may be conducted in remoulded or undisturbed sample.

• Test consists of causing a cylindrical plunger of 50mm diameter to penetrate a pavement component material at 1.25mm/minute. The loads for 2.5mm and 5mm are recorded.

• This load is expressed as a percentage of standard load value at a respective deformation level to obtain CBR value.

Definition:• It is the ratio of force per unit area

required to penetrate a soil mass with standard circular piston at the rate of 1.25 mm/min. to that required for the corresponding penetration of a standard material.


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Test for Road Aggregates

1. Crushing test1. Stone aggregates give low aggregate crushing valve

2. Crushing valve for base course shouldn’t exceed 45 %

3. Crushing valve for surface course shall be less than 30 %

2. Abrasion test1. Loss Angeles abrasion test

2. Deval abrasion test

3. Dory abrasion test

3. Impact testMaximum permissible valve is 35% for bituminous macadam and 40% for water bound macadam base course.

4. Soundness

5. Shape testFlakiness index used in road is less than 15% and doesn’t exceed 25%

6. Specific gravity and water absorption test1. Specific gravity lies between 2.6 to 2.9

2. Water absorption is less then 0.6 %

7. Bitumen adhesion test


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Bitumen adhesion test

1. Bitumen and tar adhere well to all normal types of road aggregates provided they are dry and are free from dust.

2. Several laboratory test are 1. Static immersion test

Very commonly used and very easy and simple test

2. Dynamic immersion test

3. Chemical immersion test

4. Immersion mechanical test

5. Immersion trafficking test

6. Coating test


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Various test on Bitumen

1. Penetration testDetermines hardness or softness of bitumen by measuring depth of penetration

2. Ductility testCarried to test the property of the binder in bitumen

3. Viscosity test

4. Float test

5. Specific gravity test

6. Softening test

7. Flash and fire point test

8. Solubility test

9. Spot test

10. Loss of heating test

11. Water content test


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Various test on Bitumen : Penetration test

1. Determine the hardness or softness of bitumen by measuring the depth in tenth of millimeter to which standard loaded needle will penetrate vertically in five second.

2. Needle weight of 100gm and device for releasing and locking in any position with dial gauge to read penetration valves of 1/10th of millimeter

3. The penetration valves of various types of bitumen used in pavement construction in this country range between 20 and 225, 30/40 and 80/100 grade bitumen are more used.

4. In hot climate lower penetration grade bitumen like 30/40 bitumen is preferred.


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Various test on Bitumen : Ductility test

1. Bitumen binder form ductile films around the aggregates.

2. Test is believed to measure adhesive property of bitumen and its ability to stretch.

3. Bitumen may satisfy penetration test but may fail in bitumen ductility test. So both test should be satisfied.

4. The ductility is expressed as the distance in centimeters to which a standard briquette of bitumen can be stretched before the thread breaks.

5. Test is conducted at 27’C and rate of pull of 50 mm per minute.

6. Ductility valve changes from 5 to over 100 for different bitumen grades.

7. According to ISI ductility valve should be 45 cm for bitumen grade 75 & above.


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Various test on Bitumen : Fire point test

1. Bitumen leaves out volatiles at temperature depending upon their grade.

2. These volatiles catch fire causing a flash.

3. This condition is very hazardous and it is therefore essential to qualify this temperature for each bitumen grade, so that paving engineers may restrict the mixing and application temperatures.

4. Flash point : the flash point of material is the lowest temperature at which the vapor of substance momentarily takes fire in the form of flash under specified condition of test.

5. Fire point : The fire point is the lowest temperature at which the material gets ignited and burns under specified conditions of test.


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Various test on Bitumen : Softening point test

1. It is temperature at which substance attains a particular degree of softening under specified condition of test.

2. The softening point of bitumen is usually determined by Ring & Ball test.

3. Higher softening point indicates lower temperature susceptibility and its preferred in warm climates.

4. Hard grade bitumen possess higher softening point than soft grade bitumen.

5. Softening point of various bitumen grades in paving jobs vary between 35’C to 70’C.


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Design of Bitumen Mixes

1. Selection of AggregatesAggregate posses sufficient strength, hardness, toughness & soundness

2. Selection of Aggregates GradingProperty of Bituminous mix including density & stability are much dependent on aggregates and their grain size

3. Determination of Specific gravity

4. Proportioning of Aggregates

5. Preparation of Specimens

6. Determination of Specific gravity of compacted specimens

7. Stability tests on compacted specimens

8. Selection of optimum Bitumen content


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Bituminous Mix Design : Introduction

• A good design of bituminous mix is expected to result in a mix which is adequately – strong – durable – resistive to fatigue & permanent deformation – Environment friendly – economical and so on.

• A mix designer tries to achieve these requirements through a number of tests on the mix with varied proportions and finalizes with the best one.

• This often involves a balance between mutually conflicting parameters. • The present article tries to identify some of the issues involved in this

art of bituminous mix design and the direction of current research.


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Selection of Mix Constituents : Binder

• Generally binders are selected based on some simple tests and other site-specific requirements.

• These tests could be different depending of the type of binder viz. penetration grade, cutback, emulsion, modified binder etc. For most of these tests, the test conditions are pre-fixed in the specifications.

• Rolling Thin Film Oven Test (RTFO), Pressurized Aging Vessel (PAV), Dynamic Shear Rheometer, Rotational Viscometer, Bending Beam Rheometer, Direct Tension Tester are some of the tests recommended in Super pave binder selection.


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Selection of Mix Constituents : Aggregates

• Number of tests are recommended in the specifications to judge the properties of the aggregates, e.g. strength, hardness, toughness, durability, angularity, shape factors, clay content, adhesion to binder etc.

• Angularity ensures adequate shear strength due to aggregate interlocking, and limiting flakiness ensures that aggregates will not break during compaction and handling.

• The restricted zone and control points are incorporated in order to ensure certain proportion of fines for – proper interlocking of aggregates – to avoid the fall in shear strength of mix due to excess of fines – to maintain requisite Voids in Mineral Aggregates (VMA).

• These control points and restriction zones are more as guidelines for selecting a gradation than a compulsion to be followed.


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Role of Mix Volumetric Parameters

• Bitumen holds the aggregates in position, and the load is taken by the aggregate mass through the contact points.

• If all the voids are filled by bitumen, then the load is rather transmitted by hydrostatic pressure through bitumen, and strength of the mix therefore reduces.

• That is why stability of the mix starts reducing when bitumen content is increased further beyond certain value.

• However excess void will make the mix weak from its elastic modulus and fatigue life considerations. The chances of oxidative hardening of bitumen are more, where, the mix has more voids.

• Evaluation and selection of aggregate gradation to achieve minimum VMA is the most difficult and time- consuming step in the mix design process.

• VMA specification has always been a big issue in mix design specifications. The recommendation of minimum VMA is sometimes questioned by the researchers, and is said not to be equitable across different gradations. It is seen that the bitumen film thickness, rather than the VMA, may be related to durability of the mix.


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Various mix design approaches


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Selection of base course and the surface course depend upon the following factors

1. Type and intensity of traffic

2. Funds available for the construction project and for the subsequent maintenance

3. Sub grade soil and drainage conditions

4. Availability of construction materials at site

5. Climatic conditions

6. Plants and equipment available

7. Time available for completing the project

8. Altitude at which construction has to be done


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Excavation Equipment : Power Sovels

1. Long lasting and useful class of earth moving equipment.2. One of basic equipment employed to excavate the earth and to load the

trucks.3. It is capable of excavating all types of earth, except hard rock.4. It may be crawler mounted or wheel mounted.5. Crawler mounted have low speeds but very effective in unstable soils6. Wheel mounted have higher speeds and are effective only in firm soils7. The size of Power Sovels varies from 0.375 to 5 cubic meter8. Basic parts include track system, cabin, cables, rack, stick, foot pin, saddle

block, boom point sheaves and bucket.


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Excavation Equipment : Drag Line

1. Prominent operation of dragging the bucket against the material to be dug2. Long light crane boom and bucket is loosely attached to the boom through

cables.3. Useful in digging below its track level and handling softer materials4. The capacity of dragline is indicated by size of the bucket in cubic meters5. It can be crawler mounted, wheel mounted or trucked mounted.6. Basic part dragline include the boom, hoist cable, drag cable, hoist chain,

drag chain and bucket.


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Excavation Equipment : Clamshell

1. Also named as resemblance of its bucket to a clam which is like a shell fish with hinged double shell.

2. The front end is essentially a crane boom with specially designed bucket loosely attached at the end through cables as in drag line.

3. Basic part are closing line, hoist line, sheaves, brackets, tagline, shell and hinge.


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Surface Dressing• A Surface Dressing is a process of spraying a road surface with bituminous

binder and then covering the binder with clean, crushed aggregate or natural gravel.

• These layers are then rolled in order to press the aggregate into the binder film.

• Traffic movement commences the process of chipping movement which will produce eventually an interlocking matrix.


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FLEXIBLE PAVEMENT RIGID PAVEMENT


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Types of Pavements


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Properties Flexible Rigid Design Principle

Empirical method Based on load distribution characteristics of the components

Designed and analyzed by using the elastic theory

Material Granular material Made of Cement Concrete either plan, reinforced or prestressed concrete

Flexural Strength

Low or negligible flexible strength

Associated with rigidity or flexural strength or slab action so the load is distributed over a wide area of subgrade soil.

Normal Loading

Elastic deformation Acts as beam or cantilever

Excessive Loading

Local depression Causes Cracks

Stress Transmits vertical and compressive stresses to the lower layers

Tensile Stress and Temperature Increases

Design Practice

Constructed in number of layers.

Laid in slabs with steel reinforcement.

Temperature No stress is produced Stress is produced Force of Friction

Less. Deformation in the sub grade is not transferred to the upper layers.

Friction force is High

Opening to Traffic

Road can be used for traffic within 24 hours

Road cannot be used until 14 days of curing

Surfacing Rolling of the surfacing is needed

Rolling of the surfacing in not needed.


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Factors for design of pavements IRC (37-2001)

• Design wheel load Static load on wheels Contact Pressure Load Repetition

• Subgrade soil Thickness of pavement required Stress- strain behaviour under load Moisture variation

• Climatic factors• Pavement component materials• Environment factors• Traffic Characteristics• Required Cross sectional elements of the alignment


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tre be civil

Technology