Machinery At Site

Machinery Use At Road Project

There are many operations to be done in a construction project. Such as demolishing excavation of Earth, transport of material, cleaning etc. for that, most of these operation machines are used Different machines are used difference purpose.

The selecting of machinery is done accordingly

• Nature of work
• Method of construction
• Time allowed for the work

Earth Moving Equipment

Almost all civil engineering project, start with earth excavating work on earth filling even for project where only earth filling is involved. It is necessary to excavate earth from other location for that various types of machines equipment general used such as,

Excavators

Excavators are very popular earth machine equipment it is mainly using for demolishing work & excavation. There are two types of the feet excavators.

• Hydraulically powered excavators
• Cable excavators

Hydraulically powered excavators

The conventional shovel excavators are being improved upon to provide all hydraulic operation. The advantage of powered excavators over the conventional shovel excavators are given below. The dead weight of the bucket or the boom does not come in to play. The power for excavators is derived from the trust of double acting hydraulic Ram. As the result of this the weight of the machine is reduced the rely increasing the powered, weight rate. Because of better power, weight ratio the machine can operate on surface like rock, frozen clay, sifts or boggy Soil. It is efficient & easy to control & give a shock tree operation. It reduces the service cost & operation cost.

Motor Grader

The motor grader is equipment used for leveling & finishing earth work It is particularly suited for maintenance of earthed roads The various attachments of grader are given below

The Blade : It is cured like the door blade & is fitted with replaceable edges on the sides & at the bottom.

The clarifier : It is a tool loosening hard soft. It can be attached in the front or in the rear of the machine

The Elevator : This helps the grader to pick up the cut material. This picked up material. Dropped over an inclined belt conveyor The. Attachment conveyor transmits the material in to carrier unit

Rollers : There are attached to there of the grader to consolidate the graded surface. For grading the machine mares forward & the steering is controlled by the steering wheel.

The following operation can be preformed the grader:

• Grading
• Spreading
• Side crowing
• Road cutting
• Bank dressing
• Mixing material

Backhoe Loader (J.C.B)

This type of machine is basically built up around a heavy duty industrial tractor with special purpose chassis. The engine is a water closed diesel of Approximately 60 H.P The front-end backhoe – attachments are fully hydraulically pearled

The front end loader attachment is suitable for loading tucks & tractor frailer etc. from stockpiles. It can also be used for light duly escalation jobs,

Knelling & maintenance of the road should be etc.

The front-end share has a capacity of 0.9 m3 & with a maximum loading height of 3.2m

The backhoe loading attachment is especially useful for cutting & cleaning work, earth spreading work, drain & culverts & medium duty digging jobs

The maximum digging depth is 4.3m & the maximum reach at the ground level is 5.5m with stander arm.

JBC Backhoe Loader

Earth compaction equipment

Earth compaction is one to the most important civil engineering construction processes. Encountered in the fled of constructor. For that various type of machines equipment used in our site such as, In the site, soil is compaction by using following mentioned

Tandem, double drum (ride on)

Two drums exert the compaction effort, one drum behind the other they are also available in rigid articulated frame

Double drum, walk behind

The compaction effort is erected by two drums & this is also available both in rigid & articulated frame In the rigid frame type the chassis of the frame of the machine is made as a single rigid unit. In articulated frame type the chassis or the farm is made of two units & these two units are pirated at a point between the two axles of the machine, Such that the frame could rotate in a horizontal plane through the pivot. One of the main advantages of the articulated type is that, such a machine can turned in a small area than a rigid frame type.

Double Drum

Pneumatic tired rollers (PTR)

Pneumatic tired roller are available in varying size form I tones to 200 tones. These may to tow or self propelled. These each axis consist four to Nine types. The axis are arranged in such a way that the gaps in front wheels are covered by rear wheel s this priding a complete coverage. Pneumatic tired rollers are used to compact sugared asphalt work bases of airfields & some times in earth dams.

Pneumatic Tired Roller

The compacting ability of this type depends on

• Air pressure of tires
• Width of tires
• Number of tires
• Weight of the unit

In recently developed models the type pressure can be changed without a topping the machine, thus varying the computing ability.

Rammers

Rammers are used to compact soil in restricted small areas. The most common type in the frog rammer. The comp active force is generated by dropping weights the weight of rammers vary from 70 lbs to 3cwt. There are frog rammers weighting up to one tone they are operated either by interval combustion engines or by pneumatic power.

Rammer

Vibratory Rollers

The application of vibratory rollers in soil compaction has become popular in the recent past the first towed type vibratory rollers have been manufactured in the 1940’s. In 1960’s its popularity rose sharply due to rapid advancements made in this connection today vibratory rollers have experienced outstanding success both in granular & cohesive soil’ A rotating out of balance weight produces the vibrations in this type of rollers.

The static weight of the drum applies a compaction force by inducing vibrations of that drum the compaction trace is increased this vibrating force is used to over come fractural & cohesive resistance of the material being compacted, thus aching a greater density.

The vibrating rollers are available with smith drum, sheep-fast drum or with pad foot drum however smith vibratory rollers are not recommended for compacting by a separate engine.

Asphalt Paver Finisher

A paver finisher is a machine for laying asphalt for road construction to give accurate depth, even levelling and good surface finish before rolling. We can use Paver for sub base or ABC work. But our site they have not used. But it is compared to the motor grader method, is found more suitable, because,

• Better and easier respect of levels, both longitudinal and transverse.
• Improved homogeneity of the plant prepared mix.
• Uniform pre-compaction.
• Improved adherence of asphaltic courses.

The paver can easily handle asphalt and all asphalt mixes, coated and uncoated materials, crushed stones and dry lean concrete, in fact all road making materials other than wet concrete. This is the equipment used for paving road surface with asphalt. The paver should be capable of spreading finishing and providing initial compaction of the asphalt mix. It should be able spread the mix to correct lines, grades levels, dimensions and cross section intended, either over the entire width or part of widths as case may be.

Asphalt Paver

ABC & ASPHALTING

 

Aggregate Base Course (ABC)

  Normally construction of ABC shall be commenced after completing of Sub Base and the drainage works. Aggregate Base Course is a mixture of various sizes of aggregates and quarry dust in it. Normally aggregates of 37.5mm, 20mm, and 10mm… are included.

In this project, the thickness of the ABC layer is 225mm. The motor grader is used to laying ABC. Normally the road has a cross fall of 3% from the centre the motor grader can be used to blade the road as required.

After placing it shall be compacted well using the rollers and the compaction shall be tested. Degree of compaction should be 98% or more.

Where (0-40 mm) ABC material has to be spread on a sub-base, the surface of sub-Base should be cleared from any extraneous matter.

The ABC material was spread after checking all necessary testing like sieve analysis.

After checking the underlying layer for damages or deficiencies, ABC material layer was spread in layers not exceeding 225mm & the length of spreading was 500m or less at a time.

Before starting the compaction, required water content was added and mixed ABC with the help of a water bowser and compaction was started using suitable rollers.

The compacted layer was tested for degree of compaction & moisture content. In cases where an existing ABC layer is to be improved by adding a layer of material less than 100mm thick, the existing surface was scarified to a certain depth and mixed with the imported material. After that re-compaction was started. After compaction ABC layer final finish level was taken jointly with the allowable tolerance + or – 15mm.

Grading Requirements For ABC Materials

Sieve Size	Percentage Passing
Nominal Size (mm)
37.5
50.0	100
37.5	95-100
28.0	-
20.0	50-80
10.0	40-50
5.0	25-40
2.36	15-30
0.425	7-19
0.075	5-12

Aggregate Base Bound (ABB)

Aggregate base bound also used for instead of ABC in special occasions. Aggregate Base Bound is a mixture of various sizes of aggregates including bitumen content. ABB used in the place where ABC thickness to be less than 100mm up on existing road and highly traffic area like town.

Grading Requirements For ABB Materials

Sieve Size	Percentage (%)
(20-14)	40
(14-10)	20
(10-5)	20
(5-0)	20

Bitumen Content 3.5%

Prime coat

Generally Priming works were done when the existing surface is dry or sufficiently low in moisture and normally the atmospheric temperature is above the 15 oC .Reason to apply prime coat to provide a proper bond between the layers and also to serve as a protective measure for the base or sub base.

In this CSS1 (Cationic Slow Setting) is used to prime the ABC as tack coat

Before starting Priming, the area should be demarcated & safety signs should be properly arranged. Single lane traffic should be managed so that no vehicle commuters suffer unnecessary delay.

The surface to be primed was cleaned and removed loose and deleterious material from the surface using Tractor Broom.

Prime coat was applied at required rate and temperature as per the specification requirement by mean of a bitumen distributor for large areas and by hand lance and nozzles for small and inaccessible areas achieving even distribution of prime coat over the surface. The primed surface should be allowed to cure for 24 hours without being disturbed.

Primed surface was checked & corrected if any damaged area was found and corrected area was primed, before asphalt concrete surfacing.

Reasons to apply prime coat;

• Penetrates the surface
• Coats fine particles
• Seal surface pores
• Provides a waterproof membrane
• Strengthens the surface

Tack coat

This work shall consist of an application of a tack coat to an existing pavement prior to construction of surfacing, so an to provide a bond between the two layers. When preparing the surface, the surface will be dried , thoroughly swept and rendered clean of clay, dust and any other extraneous material. The tack coat shall be applied only when the surface dry. CRS 1 or MC 30 is used to prime on regulating course as tack coat. It was applied just before laying the wearing course.

Survey & levelling

 

 

Preliminary work in road construction is surveying & leveling works. This consists of Traverse Survey, TBM Survey, and Centre Line Setting out, Centre Line marking, Cross Section Survey and Submittal of Drawings.

Traverse Survey

At the commencement of contract all the basic traverse points will be checked and if any are found to be missing or appear to have been disturbed, necessary arrangements should be made to re-establish the points and traverse survey is carried out after that.

Establishing TBMS

We did not use survey Department bench marks .The permanent concrete cube was selected to permanent bench mark. It height was assumed hundred meters. But this point is not sufficient for construction purposes. So reference to this point Temporary bench marks (TBM) should be established. TBMs are used to transfer reduce levels in road construction. Temporary bench marks should be established at the rate of four per km and also at or near all structures.

When establishing a TBM the following facts should be considered

• From one TBM it should be able to cover a long distance, when transforming reduces levels to the road.
• TBM must be a fixed one. It should not damage or disturbed during the construction period.
• It should easy to work with the established TBM. ( Easy to place the stuff on it etc. )
• So to be the TBM permanent concrete is marked point on it.

The pictorial view of the concrete TBM

 

Pictorial view of the TBM

TBM Travers

TBM traverse is done to establish the reduce levels of each and every TBM with reference to the Permanent bench marks established by us. Engineering level is used to establish TBMs.

Centre Line Marking

Centerline marking is the primary survey part in road construction. Centerline is useful while setting out for any road construction work. So it is very essential marking centre line first, before any construction work.

Equipment using for centre line marking

• Linen tape
• Road marking paint
• Nylon cord
• concrete nails

Safety equipment (e.g. Traffic cones, Bastinade boards etc.)

Centre Line Setting Out And Marking

Using total stations and approved coordinates of control points, the road centre line should be marked at every 10m interval on the road. With the aid of rope and road marking paint, the centre points marked in every 10m intervals of the road should be extended as a centre line and that established centerline should be maintained until the end of the project.

Chain age Marking

Chain age marking is done to describe the location of the road. Chain age should be marked on the road centre line in each 20m and 100m interval with meter and kilometer interval respectively.

Equipment used for chain age marking

• Linen tape
• Road marking paint
• Nylon cord
• Concrete nails

Safety equipment (e.g. Traffic cones, Barricade boards etc.)

Process of chain age marking

• Lay the nylon cord through the 20m interval centre points and draw the centerline using chalk.
• Write the chain ages using road paint.

Industrial Safety & Welfare Part 01

 

Safety is very important for any construction firm. As Engineers we must consider safety first. It means care about accident earlier and takes some action to avoid damages. It is very important to identified hazards involved in the various operations, which are carried out during the construction phase of project. Some accidents can be fatal and some can results in permanent or partial disable.

Safety precaution have been taken at site in order to avoid unexpected accident. Labours are instructed to use safety instruments which they are working. It may be difficult to find an accident free construction site some of the accidents are fatal and some results in permanent complete or partial. People began to realize that occupational accidents had economic as well as physical consequences unexpected accidents and injuries affected to construction as follows.

• Working time loss by the injured person.
• Working time loss witness and the accidents investigations.
• Production stoppages.
• Work delays.
• Possible legal and other costs.

Reduced output when the injured person is replaced and subsequently when he returns to work to work etc.

General Requirement to Prevent Accident

A safe construction site is one where anyone can go about their normal daily work without under risk. Some important areas of accident prevention would be,

• Providing adequate shoring to trenches.
• Regularly inspecting lifting and transporting equipment and there lifting an arrangements.
• Careful use of tools
• Adequate attention to temporary work
• Safe extent of temporary electrical supply with proper protection a devices
• Detail instruction all site personal
• Insistence on basic safety precaution like helmet, boost, goggles etc.
• The board mentioning “safety first” should be placed every work site.

Safety precaution equipments

There should be safety helmet, goggles, gloves, and boots etc. as available as necessary, Foremen should check whether they are used or not.

Helmet: As a protection against injures to a head from falling or flying objects helmet are used. The workmen must be wear helmet or rubberized hats.

Goggles: As a protection to the eye the goggles of right type should be used while welding or working industry places

Safety belts: Safety belt is necessity if the workmen is working at a great height .It should be sufficiently strong to taken the full weight of the wearer.

Boots: Boots are used for the protection of legs from injury & many cases it is essential for construction workers.

Gloves: Gloves of the various types are available at the site & must be used for protection of hand under difficult circumstances.

Safety nets: site was covered with the safety net to prevent any accident that can be happened to the neighbor. Having all the above plane & pre cautions any one con not say it is safe site.

Traffic Control Devices

In my training period I got a training experience at a road project so in that project we worked at urban areas. So we had to apply traffic controlling device to safety of both labours & pedestrian etc.

Besides road signs, the use of other traffic control devices is of vital importance for the road safety on work sites. Traffic control devices, other than road sings, shall be use to make the work site more conspicuous. To lead the drivers through the work site in an accurate and safe way.

Bellow following description of some useful devices.

Barricade Board

Barricade Boards are provided to indicate the section of the road closed for traffic, and should be placed at the end of the obstruction as well as along the obstruction. The boards should be support on movable stable stands and should be designed such that the boards are detachable when not in use.

 

Barricade board

Direction Board

Direction board may be used temporary at road works to indicate the direction of the road deviation. The direction board shall be black with yellow arrows when used at road work areas. The board should be supported on movable stable stands and should be designed such that the boards are detachable when not in use.

 Direction board

Barricade Tape

Barricade tape may also be used to improve the visibility of a road closure or an obstruction. However, the Barricade tape should not replace. Barricade Board or other physical closure devices for reasons that the tape can easily be removed, and the tape is not reflective. The tape could be used to supplement cones as indicated.

 Barricade tape

Pass This Side

Pass this side sing is used to divert the motorists to the way they have to drive vehicle around road work pass this side sign is usually fix at a short distance ahead the road construction section.

 Pass this side

Men At Work

Men at work sign is used to worn the motorists the men at work ahead of the road. Usually men at work sign board is fixed at seventy five meters ahead of the men working place. This sign board must be fixed clearly visible manner to the motorists.

 Men at work

 

Continue Reading

INDUSTRIAL SAFETY & WELFARE  Part 02

Industrial Safety & Welfare Part 02

Men At Work End

Men at work end sign is used to worn the motorists the end of the men working area in the road construction section.

 Men at work end

Road Narrow

Road narrow sing is used to worn the motorists existing width becomes restricted. According to type of restriction we must decided the sing type of road narrow to be used. Road narrow sign normally fix at twenty five after the Men at Work signboard

 Road narrow

Hump

Hump sign is used to worn the motorists, hump is ahead and slow down the vehicle. The purpose of Hump make the vehicle speed to death slow at hazardous places so the vehicle must slow down their speed and accident con be minimize. Hump must be constructed with hump ahead signboards fix both side of hump. Two hump ahead signboards fix thirty meters after and before the hump.

 Hump

Traffic Cones

Traffic cones are temporarily provided on the carriageway during road works and are generally placed around the obstruction or parallel to the centre line of road. Traffic cones are made of rubber or suitable plastic material having the standard color and size as shown in the figure beside and could be used to divert traffic cones around road work or trenching. The spacing between traffic cones vary according to the speeds of motor vehicles. An average cone spacing 9m is used on the straight section parallel to the centre line of the road and 12m spacing on the tapering section, A tapering angle of 30 to 45 degrees may be adopted.

 Traffic cone

Flags

Where road works are in progress the narrowing of road carriageway may permit only single file traffic and it may become necessary to provide for control of traffic at the two ends. This particularly so If the section is long and the volume of traffic is high manual control of traffic could be effected by two workman carrying red and green flags at the two end and permit only traffic in one direction at a time. In the alternative traffic control could be affected by the use of temporary traffic signals at two ends of the narrowed section.

Flagger

Before some is given the job of a flagger he must be trained. The flagger has an important task since safety for working as well as road users is a lot dependent on flagger.

The flagger must be wearing a reflective safety vest for visibility and also to enable driver to identify the flagger as a person authorized to direct traffic.

The flagger behavior is most important since driver’s tendency to obey orders given by the flagger is very much dependent on that of the flagger behaving orderly.

To direct traffic the flagger should use the red and green flags or the stop and go signs. The flagger should not wave his arms traffic but should use flag or signs and hold them steadily so the driver can see and understand the signals given.

 flaggers

Stop And Go Sign

The stop side of the sing shall be red with a white band the text “STOP” All road users are obliged to stop and wait as long as the ”STOP SIDE” is directed towards the traffic.

The “GO SIDE” of the sign shall be green with a white a while band and the text “GO” Road users may proceed when the “GO SIDE” is directed towards traffic

 stop and go sign

Welfare Facilities

The road development Authority is a semi government firm. They rules and regulation like a government department, there are lot of welfare facilities and French – benefit to employs. This firm is better to employ any level workmen to employs.

• These are the benefit
• RDA allowance
• Dead donation
• Annual bones
• Festival allowance
• Petrol allowance
• They give an uniform
• Loan facilities