Setting Out

 

Setting out is done to locate the position of the structural parts as in the detailed drawing with geometrical construction. The setting out is done to locate pile position, pile cap, column position, beam bottoms and slab boundary in the site.

Setting out is done with the reference to grid lines. When the grid lines are given in the drawing, setting out are done with reference to these grid lines using any type of technique means Suring angles or distances. In the absence of any kind of grid lines detail first the location is at the site. Considering other requirements of usage and setting out is done with reference to any base line or permanent structure. In site the base line has marked in the side of the Moors road and all grid lines are marked on around of the boundary wall.

The accuracy of setting out is depending on the usage and for which the structure is used. The method of setting out is depend considering the accuracy required and the measuring instruments availability, there are two types of measuring instruments one is measuring angles and other is by length the whole setting out work is done either by measuring angles or by measuring lengths or by measuring both. Setting out of a pile position and foundation is very important and the accuracy of the whole structure is depending on it.

Setting out was started from ground floor and continued to the other floors. If error is not allowable setting out has to be done again.

 

IMPORTANCE OF SETTING OUT

Setting out is providing pegs, levels, profiles and other information necessary for carrying out construction works. The results of setting out should be the true interpretation of the information given in the drawings.

Setting out should always have independent checks for readily detecting any errors and well recorded methodical approach for future reference. The basic requirements for setting out are the measurement of distance, the measurement of angles and the establishment of levels.

LEVELING

A temporary bench mark is established at the site for the datum of all the leveling work of the building. But in site for the easiness the 1000 mm off line of ground floor finishing level is marked on all around the land boundary wall. It can be get anywhere in site as close reference level. The ground floor finishing level is ± 0.00 in all drawings levels are given from the ground floor finishing level.

All the excavation work had to be done according to the levels given in the drawing. This was essential since all the payments for excavation and back filing were done only after taking site measurement of the excavated area and the levels happened to be more or less the same as those in the drawings.

All the slab and beam work had to be done according to the levels given in the drawings. By tightening and loosing the support jacks the correct levels can be achieved since middle part of the slab can be sag due to the weight of the concrete, levels of the middle part of the slab were established 5 mm higher.

SETTING OUT OF A COLUMN

In column setting out first the corner columns are aligned using plum bob and according to the dimension of the column sections and the centerlines are marked. Then according to the detailed drawing other position of the column centerlines are marked. After locating the centers the centerlines are marked on a cement grout base to avoid disappearance of the marks. Then kickering is done at column section dimension to locate formwork of the column.

But if there are any reinforcement bars straight to the centerlines of a column, then it is difficult to mark centerlines of that column. Then at this situation edge lines are marked instead of centerlines. It must be carefully noted that, the dimension is half of the linear face dimension lesser than the centre to centre dimension.

 

MARKING COLUMN CENTRES

• Setting out of columns is a main task.
• First the theodolite is stout over a base point and bisect a target set or another base point and clamped.
• Then nails are driven at different locations along the line which is described by the vertical cross hair of the telescope, to obtain the grid line on the floor.
• Then the line is marked using an inked thread holding between nails the lines perpendicular to the base line is also marked as required.
• The distances to the centre of each column from two perpendicular grid lines are calculated and noted down.
• Finally, by direct measurements from grid lines are marked to give the column centre.

Store Management

Store Management is an important aspect in a construction site. Material requirement should be calculated and the orders should be placed in advance so that material is readily available when work begins. The site stores in this site mainly manage receiving, issuing and storing of material and the maintenance of plant & equipments.

Characteristics Of A Well Managed Store

Availability of materials whenever required

The storage quantity should neither be too much as it would increase the storage cost and the material may get deteriorated. On the other hand the stock levels should not be too low as a material shortage may lead to delays of the project. The optimum may vary from site to site, item to item or supplier to supplier. Yet it is a good practice to keep one week’s requirement in stock.

Material should be stored in such a manner that they are easily accessible, not subjected to environmental damages and would not obstruct the site traffic.

Using the FIFO basis in issuing materials whenever possible

A properly maintained recording system facilitating the preparation of usage reports, regular stock counts, monitoring the inward and outward movements.

Documents maintained in the system

Goods Received Note (GRN)

After receiving a stock of material the Store Keeper would issue a GRN acknowledging the receipt. This has to be authorized by the project engineer. The updating of the stocks ledger and the preparation of the weekly reports are done using this.

Gate Pass

A gate pass is raised every time a site vehicle goes out of the site. This is issued either by a storekeeper or by an engineer. Though the stores do not raise this strictly a gate pass would restrict unauthorized stock transfers.

Material Requisition Note (MRN)

The subcontractors and any other person have to produce a MRN to get material from the stores. The form has to be authorized by the supervisor in charge of the work. To facilitate the monitoring of the material usage the supervisors keep a record of all the material issues authorized by them and produce a summary to the engineer in charge. The details of all the issues are transferred to book on a daily basis and a summary is used to update the Bin cards.

Purchase Order / Request Order

When a particular work has to be started the engineer in charge of the work prepares a list of material required. If the list includes items that are not in the site stores it will either be transferred from another site or purchased by the head office and transferred. This requisition is placed by through a purchase order prepared by the engineer and includes all the details required to place the order.

Bin Card

This is maintained in the stores to record the movements of the stock level of all the items. A bin card is maintained for each item in the site. The purpose of a bin card is to record the receipts and issues and the stock level of the item at any moment can readily be found from this. The bin cards in this site serve the function of a stocks ledger. The updating of this is done using the entries of the material issues book.

Invoices

When a supplier directly supplies goods to the site he will produce a copy of an invoice raised by him. The invoices are filed and sent to head office for billing. The details are used to update a book of receipts as well as weekly material progress reports.

Material Storage.

More attention should be given to the material storage within the site premises. This should be done in order to prevent any damage, wastage and to maintain working delays. Each and every item should be labeled for proper identification and also to handle easily. These labels should contain a brief description such as the date of purchase, type, size etc. Every item at the store was insured. Also it should be easy to handle and transport the materials to the required job from where it is stored.

Storing Of Fine & Course Aggregates.

Storage of both fine and course aggregate should be related to the mixer position. And also it should be considered the transport facilities to that place and the area to be used.

The required concrete amount & the number of deliveries to the site will determine the size of the storage spaces. Various sizes of Course aggregates should be stored separately to avoid mixing them together.

Storing Of Cement.

Cement should be stored on a stage raised above the floor level to avoid hardening due to dampness of the floor. Cement bags should not be stored one over the other more than 8 bags. It is better to keep about 9” distance between cement stock and the walls. Cement stocks should use before 4 months. When using cement it should issue earlier stocks previously.

Storing Of Reinforcement.

Care should be taken when storing steel (reinforcement) to avoid mixing them with different sizes of steel bars and different sizes. The different diameter of steel bars & various types were placed in separately on racks. They should be prevention form corrosion & free oil and mud. For this purpose reinforcement should be stored in a covered place.

Storing Of Tools.

Tools and equipments should be stored with security. This is because of these items are small and valuable. Workers use tools and small equipments sequently. Therefore these should be stored inside the stores where it can be reached easily. These tools and equipments should maintain well otherwise they cannot be used for a long time.

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

 

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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

CRACK TREATMENT OF THE ASPHALT BINDER COURSE

 

Main Break Water(MBW) access road occurs several cracks on the asphalt binder course. The road cracks are monitored and investigated with specialist from RDA Research & Development. This report describes the reason and remedial method of the cracks based on the investigation and consultation.

MBW access road structure consists of fallowing cross section and the core samples have been taken on the cracks.

According to core sample data, can be observed that the crack was started from CBM and reflected to the binder course surface. CRACK INVESTIGATION The crack survey carried out for the entire road and investigation detail summarized as an attached sheet. Core samples were taken from the jointly selected locations with the engineer. MBW access road cracks were categorized into two types based on crack surface appearance. Transverse cracks Longitudinal cracks Transverse cracks Transverse cracks were occurred as a perpendicular to the road center line. These cracks are reflecting from the CBM layers. According to core sample data, can be identified the fallowing crack types was happened. Some of cracks were occurred from CBM 2st layer and reflected to the binder course surface. Other cracks are started from CBM bottom layer (1st layer) and reflected to the binder course. Longitudinal cracks Longitudinal cracks were occurred as a parallel to the road centerline and which was happened due to the reflection of the CBM longitudinal joint. PROPOSAL FOR REPAIR OF CRACK Proposal of the crack repairing method is introduced by specialist from RDA Research & Development. Three conditions for reflection cracks on CBM : Cracks in the base layer must be wide enough to generate stress conditions in the asphalt surface. There is no method available to relieve the stress concentrations. The asphalt is brittle enough to crack due to upwards propagation of the stress concentration. In most cases, reflection cracks are narrow (less than 3mm) and will not adversely affect the performance of the pavement. But all the cracks on MBW access road will be treated to prevent from the possibility of propagation. As per the specialist’s proposal, Geo-Fabric material will be applied along the cracks of the binder course before laying the wearing course in accordance with manufacturer’s instructions. CRACK REPAIRING Proposed Material Polyfelt (PGM-G 50/50) to be used, material details is in Appendix Manpower Supervisor Skilled Labours Unskilled Labours Sequence Methodology Identify the crack locations and properly cleaning by air compressor. Bring the notification to the site representative of the Engineer. The binder surface is thoroughly cleaned and free from all the traces of dust and any of unsound materials. Cut the Ploy paving Fabric (PGM 50/50) for required length of the crack and 0.5m offset from the crack as following the sketch.

Apply the tack coat on the dry surface of the binder course. More details are attached the appendix document.

Install the Polyfelt PGM 50/50 and tensioning of the paving fabrics to prevent wrinkles.

Immediately after PGM installation and apply the second tack coat for asphalt wearing course.

Laying the asphalt wearing course.

Process Analysis For– Asphalt Concrete Surfacing and Concrete Structures

Process Analysis For– Asphalt Concrete Surfacing

 

Process Analysis For Concrete Structures

Civil Engineering Typical Drawings : Kerbs

Types of kerbs and their dimensions

Download Here

Construction of Bridge

 

The major materials used for the construction of bridge, but are not limited to the following.

• Cement
• Sand
• Aggregate
• Water
• Reinforcements
• Fly wood sheets
• Embankment Filling Materials (Type 1 or Type 2)
• Sub-base Materials
• Rock Fill
• Gunny Bags
• Concrete
• Guard rails
• Guard posts
• Kerbs
• Paving slabs

Equipment

The major equipment used for the construction of the Bridge includes, but are not limited to the following.

• JCB, and/or Backhoes, and/or Excavator
• Dump Trucks
• Tractor & Trailer
• 1.2 tone vibratory rollers
• Rammers / Plate Compactors
• Poker Vibrators
• Truck mixtures
• Sampling & Testing Equipment
• Total Station & Auto Level
• Truck Crane
• Generator
• Compressor
• Other minor tools

Safety Management and Control

Safety precaution will be taken complying with the Road Work Traffic Control Manual.

Method and Procedures

• After demolition and removing the existing bridge and repositioning the existing services as agreed with the Engineer, setting out will be carried out with the help of the survey data provided in the approved working drawings using total station. Engineer will be requested to inspect & approve the setting out.
• Excavation will be started up to required level as per drawings or directed by the Engineer while providing path to flow water of the existing stream. and the preparing the surface.
• Screed concrete will be done after preparing the bed. Form works & re bar fixing will be done for all wing wall bases.
• After getting approval for re-bar fixing & form works, base concreting will be done.
• Form works for wing wall will be done up to 150 mm level and wall concreting will be carried out.
• A rock fill layer will be laid up to required level noted on the construction drawings or directed by the Engineer at the bottom of the box base and the layer will be compacted using 1.2 tone rollers. The bed surface under the bottom of the box will be well prepared and the Engineer will be requested to inspect & approve.
• After getting approval for the bed surface, bottom screed concrete will be laid and the slope of the bed surface down to the existing stream will be maintained according to the Engineer’s instruction.
• Form-works, re-bar fixing for box bottom slab and concreting will be carried out accordingly, after having the Engineer’s approval for concreting.
• Concreting of walls will be done in two steps, the first step is form-work, re-bar fixing & concreting will be done up to half of the total height of the wall, and the remaining will be in the second step. In the second step, the finish level of the wall will be 100 mm down from the box top slab bottom level.
• Form-works, re-bar fixing & concreting will be done as per the drawing issued by the Engineer.
• After finishing the top slab, concreting of wing wall will be carried out. Form-works for wall will be done in three steps providing weep holes as directed by the Engineer or minimum of 1500 mm spacing.
• Stone lining with 50 ~ 200 graded rock will be done before starting backfilling.
• 1.13 After completing the back filling, concreting of end pilaster & fixing of hand rails will be done. Then after all miscellaneous works will be started and complete construction of the Bridge.

Quality Control

To ensure that the steps of the procedure are fully complied with the activities such as setting out, excavation, formwork, re-bar fixing, concreting, backfilling etc. certain inspections and verifications will be carried out as described in the above procedures.

Measurement Control

Cement concrete shall be measured in cubic meters of each class of concrete placed and excepted and shall confirmed to quantities given in drawings except for amendments approved by the Engineer.

The quantities of reinforcing steel and other items shown in the contract documents which are included in the completed and accepted structures shall be measured for payments as separate items involved unless otherwise specified.

METHOD OF INTERNAL & EXTERNAL PLASTERING ON BRICK WALLS & CONCRETE SURFACES

Method of Plastering.

• Internal plastering on surfaces of brick and concrete.
• External wall plastering.
• Soffit plastering / Soffit finishing with cement based easy plaster material and wall putty.
• Improving joint of brick walls & structural concrete joints.

Internal Plastering on surfaces of Brick and Concrete.

• Surface where plastering is to be done will be cleaned.
• Level pegs on walls will be fixed with reference to the off lines to brick walls set out in floors. (Using centre plumb bob and nylon thread).
• All the brick walls will be watered before pasting mortar on walls.
• First coat mortar filling (1:4 Cement and Sand) upto 15 mm will be applied on surfaces where required mortar thickness exceed 25mm.
• Walls and columns will be plastered 1:4 Cement and Sand to achieve semi rough finished surface.
• Vertical joint of structural columns / walls & brick walls will be treated by fixing 200mm width chicken mesh with wire nails / concrete nails by centering the mesh to the vertical wall joint.
• All the embedded service lines and provisions (Conduits, Boxes and etc. ) will be completed on brick walls and check with the MEP drawings.
• Joints between walls and beams will be formed up to a maximum of 20mm and will be sealed using 30 minutes fire rated flexible filler. (Material descriptions will be submitted for the approval of the Engineer)
• Internal plastering on surfaces of concrete columns, beams & walls which are aligned with surfaces of brick walls will be plastered and other concrete surfaces will be finished with cement base easy plaster. (Material descriptions will be submitted for the approval of the Engineer).

External Wall Plastering.

• Alignment and fixing level pegs on external wall surfaces will be done using the surveying instrument / centre plumb bobs.
• Projections on the wall surfaces will be chipped off and cleaned after completing the level pegs on walls.
• First coat mortar filling (1:4 Cement and Sand) upto 15 mm will be applied on surfaces where required mortar thickness exceed 25mm.
• Cement paste on concrete surfaces will be applied to improve the bonding of plaster to the concrete surfaces.
• Maximum width of 20mm horizontal grooves between walls and beams will be formed by cutting using grinders with diamond wheels after plastering the wall surface. This groove will be filled with approved weather sealant.
• External wall plaster will be finished with rough surface.
• 1:10 slope at the external side of the window sill will be formed while plastering the window reveals.

Soffit Plastering / Soffit Finishing with Cement Based Easy Plaster

The slab soffits and beams' sides and soffits which are to be smooth surfaced painted finished will be smoothen with easy plaster (Material literature will be submitted separately) and places where concrete surfaces are uneven, will be roughen & leveled with cement and sand mortar plaster before applying easy plaster to make surface smooth.

Improving Joints of Brick Wall & Structural Concrete

• 200mm wide Chicken Mesh will be fixed at the joint.
• Concrete surfaces will be washed and cleaned.
• Concrete surface which are to be plastered will be roughen or put spot cement slurry.

Quality Controlling & Quality Assurance

• Experienced supervisory staff will be employed for carrying out the work.
• Selected masons will be engaged for plastering work.
• Vertical and alignment of walls will be checked while plastering.
• Mixing of mortar will be done under the supervision of foremen.
• Sieved sand will be used for plaster.

Safety

Working platforms with hand rails and cat walk ladders will be fixed to access and work at higher levels.

Workers will will be provided safety helmets.

Safety belts will be provided for all employees who work at higher level plat forms.

METHOD OF EXCAVATION

EXECUTION OF WORK

• Demarcate the excavation line with working space.
• Shall obtain the written approval from employee to start excavation work.
• Shall thoroughly explain necessary details to excavator operators to get a smooth
• Work done and avoid less or over excavation.
• engineer shall continuously monitor the levels while going on the excavation

 

SEQUENCE OF WORK

Removal of surface soil and debris are carried out and clean the site. Considering the area and volume to be excavated and the different levels of excavations in ground Reservoir excavation work shall carried out in two or three places simultaneously.

In the Ground Reservoir , excavation work shall reach up to the required level in one time.

In the Back Wash Recovery Tank excavation work shall reach up to about 3.0m level in

First phase and in 2^nd phase shall reach up to final required level.

 

Transporting soil

• Excavated soil will be transported out from the site and soil suitable for back filling shall
• Be stocked at adjoining land to the site. All the vehicle sending out from the site are
• Recorded and daily report will be submitted to the employee. Excavation work will
• Continue in night time too.

EQUIPMENT, MACHINERY AND VEHICLES

The following vehicles and machineries are available foe the excavation works. These

Will be employed time to time as necessity arises.

1. Excavator 0.7 m³ - 2nos
2. 14.15m³ Dump Truck - 2nos.
3. Loader Backhoe - 1 nos
4. Baby Dumper - 2 nos.
5. 9.00m3 Dump Truck 2 nos

 

SAFETY AND QUALITY ASSURANCE

The following measures will be taken to ensure the safety and security of machinery, Vehicle and personal.

a) All machinery will be operated by well trained operators. Operator assistants will be employed for machineries like crane, backhoe, backhoe loader, etc.

b) Only vehicles having valid revenue licenses and necessary insurance coverage will be used for transport of soil. Only drivers having valid driving license will be permitted for this work. The driver will be assisted by a helper in each heavy vehicle.

c) Proper access will be provided with suitable slopes

d) Necessary barricades will be fixed either with fence or with barricade tapes where necessary to assure the safety of the persons, vehicles and machineries.

e) The whole activity covered by a C.A.R. Policy

f) Continues watchmen will be provided for excavation and machinery movements.

 

SECURITY OF WORK

a) All entry / exit records will be maintained at site and will be forwarded to the Engineer if requested

b) Identify details of all employees of works including operators, operator assistance, drivers, and driver helpers will be maintained under custody of Administrative Manager.

c) Gate pass will be issued with necessary approval before exit of each vehicle.

HEALTH AND EVIRONMENTAL PRECAUTIONS

a) Excess soil will be dumped to filling lands after obtaining permission from all relevant government authorities.

.b) Drum Truck leaving the site with soil will be covered by polythene cover.

METHOD OF BRICK MASONRY WORK

Method Statement

This method statement will be established for the construction of brick masonry walls and the related work which are to be completed with brick walls. Brick masonry walls in the scope of work are 225mm thick & 112.5mm thick brick walls. These brick walls will be built with 1:5 cement sand mixture.

Description.

Brick walls will be built for internal partition & as well as perimeter walls of the building. All brick walls will be constructed by maintaining the verticality of walls and the location of the wall as per the construction issued Architectural drawings / approved shop drawings for brick walls in each floor.

While constructing the brick walls, opening for the doors, windows & services will be provided according to the dimensions of doors, windows & the dimensions for openings shown in the service drawings by allowing cement / sand plaster thickness of 15mm in each side of the opening.

Method of Brick Masonry.

• Method of brick will be described as follows,
• Construction of brick wall.
• Construction of stiffener columns, beams & lintels.
• Providing reinforcement anchors to the stiffener columns from the structural beams, walls & columns.

Construction of brick wall

• Marking for brick walls & openings will be done on structural floor slab according to approved shop drawings.
• The floor slab where brick walls to be built will be cleaned.
• Reinforcement for stiffener columns will be anchored using HIT-HY 150 chemical at the place where Reinforcement starters would not be provided.
• Brick walls with 225mm thick will be built to around 1.5m height in first stage and balance will be completed after curing the wall.
• Brick walls with 112.5mm will be built to around 1.0m height in each curing.

Construction stiffener columns, beams & lintels.

• Stiffener columns will be cast after completing each part of brick walls (~1.5m height)
• Lintel beams & stiffener beams will be cast as per the approved drawing at the required level.
• If the Reinforcement starters would not be provided at the location of stiffener beams & columns from the structural elements, chemical anchor HIT- HY150 will be used for anchoring Reinforcement to the structural elements.
• If the Reinforcement starters would not be provided at the location of lintels from the structural elements, chemical anchor HIT - RE 500 will be used for anchoring reinforcement to the structural elements.

Providing reinforcement anchors to the stiffener columns from the structural beams, walls & columns (Refer the sketch /no 01 attached)

• These Reinforcement anchors would be provided while concreting the structural elements and construction detailing for anchors will be carried out as per the attached sketches.
• If the anchors have not been provided as per the approved shop drawing / required dimensions chemical anchors HIT- HY150 will be used for anchoring the missing Reinforcement. (Refer attached sketch No 02 for detail of chemical anchoring)
• Anchors provided for all the stiffeners columns and the perimeter brick walls at the top of wall will be clipped with 22mm diameter PVC pipe clip & 16mm diameter PVC pipe respectively & filled with grease.
• 12mm thick polystyrene sheet layer will be place at the top of internal brick walls just at the soffit of structural elements (beam / slab)
• 12mm thick polystyrene sheet layer will be placed at the top of perimeter brick walls just at the soffit of perimeter beam. This gap at the external face and the internal face will be filled with waterproofing sealant. Literature of waterproofing material will be provided.

Quality Assurance and Quality Control System

• Following checks & inspections will be carried out.
• Locations of brick walls & openings in brick walls will be marked on floor by referring the off lines of main grids.
• Verticality & the alignment of brick walls will be checked by using mason’s plumb.
• Cement/ sand mortar will be mixed manually or mechanical mixer & volume of cement & sand will be measured using gauge boxes. Mix ratio of cement & sand is 1:5 (by volume)
• Inspection with the engineer’s representative will be carried out while work is in progress.
• Sample of Bricks will be submitted for the approval of engineer.

Project Quality Assurance

Quality Assurance Procedures

In order to assure the product quality, the quality of the following resources will be assured.

1.        Human Resources: Suitable personnel will be deployed to the processes, based on the qualifications and experience. In addition to that necessary training will be provided for continuous improvements and new technologies. 

2.        Machines and Equipment's: All the construction machineries and equipment's will be serviced and calibrated periodically as stipulated in the schedule to make sure the accuracy and proper functioning.

Device	Frequency of checks	Adjustments	Calibration
Theodolite	Once in 6 month	When Required	Annually
Level Sets	Once in 6 month	When Required	-do-
5m Tapes	Once in 3 months	When Required	-do-
30m Tapes	Once in 3 months	When Required	-do-

3.        Material: All the construction materials will be assured to comply with the standards and specifications. Relevant tests will be carried out as stipulated in the standards, codes and specifications periodically and as and when required.

Products	Frequency of checks	Adjustments
Test cubes	7 days & 28 days	When Required
Slump Cone	Prior to concerting	When Required

 4.        Methods: Shop drawings and method statements will be prepared as per the drawings, specifications and consultation with specialists.