mcm 511 - road making equipments

7/27/2019 MCM 511 - Road Making Equipments

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MCM 511

CONSTRUCTION EQUIPMENT

MANAGEMENT

Road Making Equipments

Prof. Debopam Roy



Typical Cross Section of Road

EMBANKMENT

SUBGRADE

GRANULAR SUB BASE

WET MIX MACADAM (BASE)

DENSE BITUMEN

MACADAM (BINDER)

BITUMINOUS CONCRETE (WEARING)

SHOULDERPrime Coat /

Tack Coat

EXCAV

ATION



Broad Categories

• Earthmoving Equipments

• Hauling Equipment

•

Mix production plants• Mix Laying Equipments

• Compaction Equipment

• Accessories



LAYER RAW MATERIAL MAJOR EQUIPMENTS

DISMANTLING, CLEARING

& GRUBBING

Milling Machine, Tractor

Ripper, Earthmovingequipments

EXCAVATION Earth Moving Equipments

EMBANKMENT Suitable soil Earthmoving Equipments

SUBGRADE Suitable Soil , Cement/Lime Earthmoving Equipments,

Soil StabilizerGSB / SHOULDER Natural River Bed Material,

Overburden, Milled

Material, Blended mix

Earthmoving Equipments,

Pugmill

WMM/WBM Course & Fine Aggregates,

Water

Pugmill, Paver/Grader,

RollersBM/DBM/BC Course & Fine Aggregates,

Bitumen

Hot mix plant, Paver,

Rollers

Prime Coat / Tack Coat Bitumen Emulsifiers Bitumen Sprayer, Tractor



GSB Production

• For natural GSB no blending required

• In some cases, materials from differentsources may be blended to achieve desired

properties (drainage & strength)• The blending of raw materials to produce GSB

can be done at stock yard using

Excavator/Wheel Loader• In some cases a Pug-mill is used to achieve

desired mix properties



WMM Production



Parts of WMM Plant

• Aggregate Feeding system – Cold Feed Bins &

Conveyor

• Water Supply

• Pug-mill

• Discharge System – Load out Conveyor &

Surge Silo• Control Cabin



Cold Feed System

• 3-4 open top bins mountedtogether as single unit

• Each bin used to store certainfraction of aggregate

• At the bottom of each binthere is a gate for controllingmaterial flow and a feeder unitfor metering the flow

• The aggregate in rightproportion is carried to themixer, by conveyor belt



Feeding of Bins

• Option 1 : Direct Feeding – A ramp is provided upto brim of bins, which isused by dumpers/wheelloaders to feed the bin

• Option 2: An extra bin isprovided at Ground level,where the dumper/wheel

loader empties aggregate,and then the aggregate istaken to the right bin,through a radial conveyor



Water Supply

• Continuous Water Supply is ensured by

installing Water tank & Pump

• A Bore-well may be required for ground water

source

• Water Flow meter with Sensor to control flow



Pug mill

• A pug mill is a machine in whichmaterials are simultaneouslyground and mixed with a liquid

• A typical pugmill consists of a

horizontal boxlike chamber with atop inlet and a bottom discharge atthe other end, 2 shafts withopposing paddles, and a drive

assembly• To achieve uniform mixing, a

pugmill’s live zone should becompletely filled with mix



Discharge System

• Discharge system is notrequired if Pug mill isplaced at sufficient height

• However, in most cases,

the mix from pug mill istaken by a Load out Beltconveyor to a storage silo

• This ensures continuous

operation• The trucks are fed from

under the storage silo



Salient Features

• Capacity – 100-200 TPH

• Hire Charge – Rs. 1-2 lakh / month

•

Autometic / Semi-autometic / Mechanical• Leading Brand : Local Manufacturers



Asphalt Production

• An asphalt plant is a high-tech group of

equipment which is capable of uniformly

blending, heating, and mixing the aggregates

and binder, while at the same time meetingstrict environmental regulations

• Two types of plants are in use: Batch Heater &

Drum Mix. Drum Mix plants are most commonnow.



Batch Heater Plant

• Old Technology

• Weigh batcher weighs the raw aggregates into heaterdrum / drum dryer, where it is heated to desiredtemperature

• Hot aggregate discharged into mixing drum / pug mill,where filler & binder is added

• Blend is mixed and discharged either directly or into aweighing and collecting hopper

•

Capacity is low (Tens of Tons per hour)• Can be effective where short production runs with

frequent change in recipe is used



Drum Mix Plant



Parts of Drum Mix Plant

• Cold Feed System

• Asphalt HandlingSystem

• Drying & MixingDrum

• Conveyor

•

Dust Collector• Storage Silo

• Operator Cabin



Cold Feed System

• Similar to WMM plant

• Since mixing is done in drum, aggregate mustbe weighed prior to feeding

• Since Aggregate weighed prior to drying,moisture content must be monitored, andweight adjusted accordingly

•Vibratory Screen used to remove the oversizedand unnecessary materials from feeder



Asphalt Handling System

• Liquid Bitumen is storedin Metallic Tanks

• Temperature of thebitumen should be in

range of 300F to enablepumping and mixing butprevent flash

• Heating can be done

either directly (using HSD)or by hot oil system (usingFurnace Oil)



Drying & Mixing Drum

• This inclined rotating cylindrical drum dries theaggregate and performs the mixing

• Consists of a long tube with flights for tumblingthe aggregates and the mix, a burner for heatingaggregates, and a spray bar for applying bitumen

• Aggregate is fed into one end, and is dried, andheated while moving along the drum, usingHSD/FO

• Bitumen is sprayed near the discharge, and thedrum rotation, with flight in drum does themixing



Drying & Mixing Drum

• Slope : 40-80mm/m

• Rotation speed : 5-

10rpm

• Diameter: 1-4m

• Length: 5-20m



Conveyors

• 2 sets of Belt Conveyors are used – for feedingaggregates into the drum & carrying mix tostorage silo

•

Additionally Radial conveyor may be used to fillbins

• Conveyors are equipped with load cells forcontinuous monitoring of weight, and limit switch

for emergency switch offs• Conveyors are the parts of the plant susceptible

to maximum Wear & Tear



Dust Collectors

• Because of air pollution requirements, asphalt plants are equippedwith dust control systems – The two most commonly utilized systems are the water venturi approach

& the cloth filtration “baghouse” system

• The wet approach does require the availability of adequate water

supplies – It introduces water at the point where dust laden gas moves through the

narrow throat of a venturi-shaped chamber

– The dust becomes entrapped in the water and is thereby separated fromthe exhaust gas

• The dry baghouse systems allow mechanical collection and

recycling of fines – The system works by forcing the dust laden gas through fabric filter bags

which hang in a baghouse

– The dust falls into hoppers in the bottom of the baghouse and is moved byaugers to a discharge vane feeder



Storage silo

• Since drum plants produce acontinuous flow of asphalt , theoutput must be stored in silos

• Upright cylindrical structures,

“silos”, fed at the top by a drag flightconveyor, and discharge totransport trucks through bottomdump

• Sealed/Filled with inert gas to

prevent hardening & ageing of mix• Drop control methods to avoid

segregation

• Insulated to retain heat



Operator Cabin

• Asphalt plants today are allelectronically controlled

• A fully automatic control cabin withAC/DC control panel, on boardelectric power console, distribution,

switch board, is provided forcontrolling the quantity and qualityof production with operator sittingin A/c comfort.

• In addition to controlling pantoperations, this facilitates controlling

mix recipes, checking qualityparameters, storing and printingdata, monitoring health of plant,and identifying problems if any.



Salient Features

• Capacity – 100-500 TPH

• Needs DG back up of >500 kVA

•

Acquisition Cost – Rs. 50-200 Crores• Hire Charge – Rs. 10-30 lakhs/month

• Leading Brand – MARINI



Existing Surface Preparation for

Overlays• The degree of surface preparation for an

overlay is dependent on the condition andtype of the existing pavement

• The overlay scheme is decided based onresults of Benkelman Beam Deflection

Test• If the existing pavement is structurally

sound, it is – cleaned,

– repaired wherever necessary,

– coated with a bonding agent, – a leveling / profile corrective course is applied

• If the existing pavement is structurallyweak, it is completely dismantled byripping or milling and reconstructed



Leveling Course / PCC

• Initial lifts placeddirectly on to theexisting pavement to filllow spots in the

pavement

• Essential for SlopeCorrection

• Generally asphalt mix of a lower grade than thestructural layers is used

Existing Pavement

PCC

New Pavement



Ripping

• Dismantling of existingpavement can be doneby a Tractor Ripper oran Excavator

• The ripping action issimilar to plowing, usinga stronger ripper

• The method in recenttimes has beencompletely replaced bymilling



Milling

• Milling (also called grinding orcold planing) can be used todismantle/smoothen anexisting pavement

• Rather than filling in low spots,

as a leveling course does,milling removes the highpoints in an existing pavementto produce a relatively smoothsurface

• The basic components of a

milling machine are – a cutting drum to mill the

existing pavement

– a vacuum to collect the milledparticles

– a conveyance system to

transport the milled particles toa dump truck for hauling



Advantages of Milling

• Eliminates the need for complicated leveling courses and problemswith quantity estimates for irregular leveling course thicknessesused to fill existing pavement depressions.

• Provides RAP for recycling operations.

• Allows efficient removal of deteriorated flexible pavement material

that is unsuitable for retention in the pavement structure.• Provides a highly skid resistant surface suitable for temporary use

by traffic until the final surface can be placed.

• Allows curb and gutter lines to be maintained or reestablishedbefore flexible overlays.

•

Provides an efficient removal technique for material near overheadstructures in order to maintain clearances for bridge structures,traffic signals and overhead utilities.



Salient Features

• Cut Width – 75mm to 4.5m

• Cut Depth – Up to 250mm per pass

• Production Rate – 100-200 tons/hr

• Material Size after milling – 95% passing the50mm sieve

• Acquisition Cost – Rs. 2-3 Crore

•

Hire Charge – Rs. 6-8 lakhs• Diesel Consumption – 20 ltrs/hr

• Leading Brand - WIRTGEN



RAP (Reclaimed Asphalt Pavement)

• Existing asphalt pavements represent a large investment in aggregates andasphalt. By reclaiming these materials, using either cold milling or rippingmethods, much of that investment can be recaptured

• Disposing of dismantled pavement material is an environmental hazard. Itcan be avoided by incorporating it in new pavement

• Further usage of milled material reduces the quantity of aggregatecrushing, thus reducing the carbon foot print

• The RAP are combined with virgin aggregates, additional asphalt, and/orrecycling agents in a hot mix plant to produce new paving mixes

• The new mix design will have to account for both the gradation of theaggregate in the RAP and the asphalt content of the RAP

• The mixing of virgin material and RAP to produce a new mix is performedby heat transfer methods, or using a double drum system to preventexposure of asphalt content of milled material to direct flame.

• In case, mix design using RAP is not approved, it can be used in WMM/GSB



RAP production in double barrel drum-

mix plant



Laying of Prime & Tack Coats

• Prime Coat is a layer of emulsifier applied above

base course (WMM) before laying Asphalt

• Tack Coat is a layer of emulsifier applied to bond

between old and fresh layer of asphalt

• Before applying the coats, the underlying surface

is cleaned using compressor, and mechanical

broomer• Specially designed distributer truck is used to lay

the bitumen emulsion



Mechanical Broomer

• A Brush, made of metal wire& nylon bristles, is fixed tothe rear of a tractor, andtowed on the road

•

A debris hopper is attachedwith main frame in front of bush, with lever-controlledunloading mechanism

• Hire Charge – Rs. 10000-

15000 / month• Diesel Consumption – 2

ltrs/hr



Bitumen Sprayer

• These trucks must be able to apply the liquid asphalt to asurface at uniform rates

• They have insulated tanks for maintaining material temperatureand are equipped with burners for heating the asphalt materialto the proper application temperature

• Discharge pumps are used to maintain continuous and uniformpressure for the full length of the spray bar

• The nozzle angle must be set properly, usually 15 - 30° from thehorizontal axis of the spray bar so that the individual spray fansdo not interfere or intermix with one another

•The height of the nozzle above the surface determines the widthof an individual fan

• To ensure the proper lap of the fans, the nozzle (spray bar)height must be set and maintained



Bitumen Sprayer

• The factors which affectuniform application are:

• The asphalt spraying temperature

• The liquid pressure across thespray bar length

• The angle of the spray nozzles

• The nozzle height above thesurface

• The distributor speed

• The relationship between theapplication rate and the truckspeed is obvious; truck speedmust be held constant during

the spraying to achieve auniform application

• Hire Charge – Rs. 40000-80000/month

• Diesel Consumption – 8 ltrs/hr



Laying Of Asphalt

• Asphalt is laid using aSensor Paver

• The sensor paverensures the line, level,and quality of mix

• The mix is loaded in thefront hopper, carried tothe rear by set of flightfeeders, spread out by aset of augurs, andleveled by a screed.



Parts of Paver

• Consists of a Tractor Unit & a Screed• Tractor (Material Feed System)

– Push Roller & Truck Hitch

– Hopper

– Conveyor

– Augur

• Screed – Screed Plate; Strike-off plate; Screed Arms; Depth

crank; Screed Heater; Screed Vibrator; ScreedExtension

• A Windrow Elevator may sometimes be used



Push Roller & Truck Hitch

• The push roller is the

portion of the paver

that contacts the

transport vehicle• The truck hitch holds

the transport vehicle in

contact with the paver

• They are located on the

front of the hopper



Hopper

• Pavers can receive mix directlyinto their hoppers from reardump or flow bottom trucks

• The hopper is used as atemporary storage area for

HMA delivered by thetransport vehicle

• Hopper sides (or “wings”) canbe tilted up (or “folded”) toforce material to the middlewhere it is carried to the rear

by the conveyor system• Hoppers can also be fit with

inserts to allow them to carrymore mix



Conveyor

• The conveyor mechanismcarries the mix from thehopper, under the chassisand engine, then to theaugers

• The amount of HMA carriedback by the conveyors isregulated by either variablespeed conveyors and augersor flow gates, which can be

raised or lowered by theoperator or, more often, byan automatic feed controlsystem



Augur

• The auger receives HMA

from the conveyor and

spreads it out evenly

over the width to bepaved

• There is one auger for

each side of the paver

and they can beoperated independently



Windrow Elevator

• Paving operation is often affectedby delay in truck loads. This causeundulation in the mat

• Windrow elevators weredeveloped to address transferand truck queuing effects on mat

quality• The flight system of the elevator

continuously lifts the mix into thehopper from the windrow

• If queuing delays individualtrucks, the effect to paving speed

is limited or nonexistent becausethe windrow storage allows thepaver to continue moving



Screed

• The most critical feature of the paver is the self-levelingscreed unit, whichdetermines the profile of the HMA being placed

• The “floating” screed is freeto pivot about its pinconnections. This pin-connected tow arm

arrangement allows thescreed to be self-levelingand gives it the ability tocompensate for basesurface irregularities



Screed

• Screed Plate - The flat bottom portion of the screed assembly that flattens andcompresses the

• Screed Angle - The angle the screedmakes with the ground surface

• Strike-off plate - The vertical plate justabove the leading edge of the screed used tostrike off excess HMA and protect the screed’s

leading edge from excessive wear• Screed Arms - Long beams that attach

the screed to the tractor unit

• Tow point - Point at which the screed armis attached to the tractor unit

• Depth crank - The manual control deviceused to set screed angle and ultimately, matthickness

• Screed Heater - Heaters used to preheatthe screed to mix temperature

• Screed Vibrator - Device located withinthe screed used to increase the screed’s compaction effort.

• Screed Extension - Fixed or adjustableadditions to the screed to make it longer



Screed

• Since the screed is free floatingit will slide across the HMA atan angle and height that willplace these six forces inequilibrium

• When all the forces acting onthe screed are constant, it will

ride at a constant elevationabove the grade or follow thestringline

• When any one of these forces ischanged, the screed angle andelevation will change (whichwill change the mat thickness)

to bring these forces back intoequilibrium

• In typical paving operations thescreed angle is manuallyadjusted to control matthickness, using a thicknesscontrol screw or depth crank



Factors affecting Paver Performance

• Screed Angle of Attack – This angle is the principal mechanical factor affecting variations in mat thickness

– Change in angle affects the equilibrium of forces, hence mat thickness is changed

– It regulates the amount of material passing under the screed in a given distance

• Speed of Paver – Paver speed affects mat thickness by changing the screed angle

– If a paver speeds up and all other forces on the screed remain constant, thescreed angle decreases to restore equilibrium, which decreases mat thickness,and vice versa.

• Head of the material ( Amount of Mix in front of screed) – If the material head increases (either due to an increase in material feed rate or a

reduction in paver speed), screed angle will increase to restore equilibrium, which

increases mat thickness, and vice versa.• Tow Point Elevation

– As a rule-of-thumb, a 25 mm (1-inch) movement in tow point elevation translatesto about a 3 mm (0.125 inch) movement in the screed's leading edge

– Tow Point Elevation changes with change in tractor elevation, due to roughness inthe surface over which it drives

–

As the tow point rises in elevation, the screed angle increases, resulting in athicker mat, and vice versa.



Screed Control of Sensor Paver

• Sensor Pavers operate using anautomatic screed control, whichcontrols tow point elevation usingan external reference other thanthe tractor body

• The mat thickness is maintainedusing grade sensors tracing the

external reference, and hence thename

• Erected String line

• Mobile reference

• Joint matching shoe / ski

• In addition to grade control, the

screed can also be set to controlpavement slope and/or crown.

• A slope controller uses a slopesensor mounted on a transversebeam attached to the screed todetermine screed slope, thenadjusts screed slope to the desired

amount



Salient Feature

• Capacity – > 500 TPH, Restricted by capacity of plant

• Width – Basic width is 2.5m. Can be extended up

to 9m• Diesel Consumption – 7-10 ltrs/day

• Acquisition Cost – Rs. 1-2 Crores

• Hire Charge – Rs. 1-5 lakhs/month

• Leading Brand – VOGELE, BITELLI,INGERSOLRAND



Compaction of Asphalt

• Because of the relationships between pavement air voids andmechanical stability, durability and water permeability, asphaltpavements are designed based on the mix being placed at aspecified density

• Four basic type of equipments are available for compaction of

asphalt mix – The Paver Screed

– Smooth Drum Steel Wheel Roller (static)

– Smooth Drum Steel Wheel Roller (vibratory)

– Pneumatic Tire Roller

•

Each piece of equipment compacts the mix by two principal means – By applying its weight to the HMA surface and compressing the

material underneath the ground contact area

– By creating a shear stress between the compressed materialunderneath the ground contact area and the adjacent uncompressedmaterial



Paver Screed

• The screed takes the head of HMA from the

material delivery system, strikes it off at the

correct thickness and provides initial mat

compaction• Screed compaction depends upon screed weight,

frequency and amplitude of Screed Vibrator

•

Approximately 75 to 85 percent of the theoreticalmaximum density of the HMA will be obtained

when the mix passes out from under the screed



Static Smooth Drum Roller

• Self-propelled compactiondevices that use steel drumsto compress the underlyingHMA

• Can have one, two or eventhree drums, although tandem(2 drum) rollers are most oftenused

• Water on sprayed on thedrums to prevent mix fromsticking

• Width – 860-2150mm;Diameter – 500-1500mm

• Rarely seen at present, otherthan for small projects



Vibratory Steel Wheel Rollers

• Some steel wheel rollers areequipped with vibratory drums

• Drum vibration adds a dynamicload to the static roller weight tocreate a greater total compactiveeffort

• Produces greater friction andinterlock than could be achievedwithout vibration

• Roller drum vibration is producedusing a rotating eccentric weightlocated in the vibrating drum (or

drums) and the force it creates isproportional to the eccentricmoment of the rotating weightand the speed of rotation



Vibratory Steel Wheel Rollers

• Operators can turn the vibrationson or off and can also controlamplitude (eccentric moment)and frequency (speed of rotation) – which affects the Dynamic(Compactive) Force

•In general, higher frequenciesand lower roller speeds arepreferred, which – increases the compactive effort

– provides a smoother mat

– 3000 vibrations/min, and 5kmphgives recommended impact

spacing of 33-37 impacts per m.

• Increase in vibratory amplitudeincreases compactive effort, butit can fracture aggregateparticles. Better solution is tomaintain low amplitude vibration,

and increase no. of passes.



Pneumatic Tire Roller

• Employs a set of smooth (no tread)rubber-insulated tires on each axle;typically four on one axle and five onthe other

• The tires on the front axle are alignedwith the gaps between tires on therear axel to give complete and uniform

compaction coverage over the width of the roller

• Compactive effort is controlled byvarying tire pressure, which is typicallyset between 400 kPa (60 psi) and 800kPa (120 psi)

• Once the tires heat up to near mat

temperature, they do not pick upappreciable amount of binder

• In addition to a static compressiveforce, pneumatic tire rollers alsodevelop a kneading action betweenthe tires that tends to realignaggregate within the mix



Salient Features

• Weight is > 20 MT

• Diesel Consumption – 10-12 ltrs/day

• Acquisition Cost – Rs. 25-30 lakhs

• Hire Charge – Rs. 1-2 lakhs/month

• Leading Brand – BITELLI, INGERSOLRAND

Comparison of Pneumatic Tire Roller



Comparison of Pneumatic Tire Roller

wrt. Drum Rollers

Advantages• They provide a more uniform

degree of compaction

• They provide a tighter, densersurface thus decreasing

permeability of the layer• They provide increased density

• They compact the mixturewithout causing checking(hairline surface cracks) andthey help to remove any

checking that is caused withsteel wheeled rollers

Disadvantages• The individual tire

arrangement may causedeformations in the mat thatare difficult or impossible toremove with furtherrolling. Thus, they should notbe used for finish rolling

• If the mix binder contains arubber modifier, binder pickup(mix sticking to the tires) may

be severe



Factors affecting Compaction

• Rolling temperature – To compact a mix properly, the asphalt binder must be fluid enough to

allow the aggregate portion to assume a new configuration

– The temperature at which the mix was produced is the important factor indetermining the time duration that is available for hauling, placing, andcompaction

– To extend the available time, it may be necessary to use trucks havinginsulated bodies

– Rolling should begin at the maximum temperature possible

• Rolling steps –

Compaction of an asphalt mat is usually viewed in terms of three distinctsteps:• Breakdown

• Intermediate

• Finish




– The breakdown step seeks to achieve a required density within a timeframe defined by temperature constraints and consistent with paverspeed

– There is an optimum mix temperature range for achieving propercompaction

• If the mix is too hot, the mat will tear and become scarred

•

If the mix is too cold, the energy requirement for compaction becomesimpractical because of viscous resistance

– Sometimes density cannot be achieved by a single roller within the timeduration available

• In that case an intermediate rolling step is required to supplement thebreakdown step in reaching the required density

– Steel wheel rollers are used for finish rolling

– Pneumatic rollers are multipurpose and can be used for breakdown andintermediate rolling

– The vibratory steel wheel-type rollers are usually the roller of choice forbreakdown and intermediate rolling because of their adaptability to arange of mixes and differences in mat thickness




• Roller capacity – Paver speed and production is set by the asphalt plant capability. Net

roller speed is influenced by:• The gross roller speed

• The number of passes

• The number of laps

• The overlap between adjacent laps to cover the mat width

• The extension overedge

• The extra passes for joints

• The nonproductive travel (overrun for lap change)

– Roller capability for a project must match the net roller speed with theaverage paver speed

– It must be remembered that increased roller speed simply reducescompactive effort, so speed alone cannot be used to compensate forincreased production



Other Equipments

• Dumper Trucks – MixTransportation

• Tele-Light Mast – NightPaving

•

Tractor/Truck – Transporting Tools &Tackles

• Water Tanker

• Conveyance Vehicle

• Power Generator• Wheel Loader

• Weigh Bridge

Plant

Operations



Tools & Tackles

• Rakes

• Lute

• Squeegees

• Depth Gauge

• Straightedge

• Cutting Tools / Scraper

• Broom & Brush



Critical Issues

• Minimizing Downtime

• Right Usage

• Regular maintenance to reduce breakdown

• Idling of costlier resource due to shortage of

cheap resource

• Availability of spare parts

• After sales service



Supply Chain Management

• Milling – Plant – Dumper – Paver – Roller – Manpower – Accessories

• Continuous paving is essential for productivity,schedule-adherence, quality, and cost

• Most Critical Activity of Road Project – Managethe multiple resources to ensure continuouspaving

• Critical Success factor – Resource Planning

(optimum mobilization & usage); EquipmentAvailability (low down time); EquipmentPerformance (quality & productivity)



Problem

• You are required to do the equipment planning for a four laning project of an existing 2 lane highway in the state of Maharashtra.

• Length of Project – 50kms

• Duration – 30 months

• Complete dismantling & reconstruction of existing road is required

• Existing road asphalt thickness 150mm

• New pavement: 150mm DBM, 50mm BC

• There is one central camp and plant

• For how many months you need to mobilize a 100 tph milling machine

• What capacity of asphalt plant you shall propose

• How many dumpers for transportation of asphalt and milled material

• What average paver speed will match the plant production

• Considering 2m wide drum with 10% overlap, & 3 passes for compaction,how many rollers are required

• Assume 80% productivity & 16 working hours per day

mcm 511 - road making equipments

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