MGNREGS

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Training-cumWorkshop of Field
Engineers
22nd May to 4th June, 2010
AIM OF THE TRAINING
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Brief understanding on functioning our daily duty
Social responsibility of building better world with
number of hurdles.
Conflict demands on the technical aspects.
Not feasible to use a single decision making process
to solve every ethical dilemma,
At times it may force a technical personal to
subjugate his or her self interest.
Procedural constraints and lack of
awareness/exposure
Positive impacts so as to convince the field
engineers in adopting such procedure at placed
found effective.
SCHEDULE OF DISCUSSION
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Documentation of estimate and case record
T/S and A/A
PREPARATION OF ESTIMATE ON
 Road work
 Concrete road
 Farm pond
 RENOVATION OF POND / NEW POND
 Building
 BNRGSK building
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Software adaptation on estimate

Utilisation and duties of Gram Sanjoyok
GUIDELINES FOR PREPARATION OF ESTIMATE AND
SUBMISSION FOR TECHNICAL SANCTION
(1)
BUILDING
The building estimate should contain the following
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
a site plan showing north point.
Approved neat drawing showing the plan, elevation and cross
section to a suitable scale.
Specification and soil data
detailed specification of items of work as per codal provision
such as IRC/IS specification
trial pit section of the soil/ soil test report.
Design particulars.
Quarry chart
Detailed analysis of rates
General abstract
In case of renovation, addition, alteration of the building,
previous history of the case of work.
(2) ROAD
The road estimate contains
a) history, designs, scope, rates, specifications,
references, cost, mode of execution etc.
b) Detail estimate, abstract.
c) Bar chart
d) Plans, longitudinal and cross section and initial
level.
e) Drawings of C.D. works.
f) Quarry chart.
GENERAL

In case of earth work relating to new roads/ widening of existing
roads, renovation and excavation of a tank, the initial level of existing
formation should be recorded.
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Pre-measurement should be check measured by the higher authority
before execution of the work
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drawing showing the proposed final levels.
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The code and practice prescribed by the I.R.C. and I.S. should be
followed in general.
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For lump-sum provisions for an item, the detailed estimate should be
got approved.
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References to the existing structures / sites should be indicated.

The estimate should be prepared as per the requirement of the
project and not in piece meal basis.
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Estimate shall not be splited up.
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Sanctioned estimate to be entered in the register at G.P. level and at
Block level assigning a number and date.
MATERIAL USE AND COMPREHENSHIVE STEPS
FOR ROAD WORK : (UP TO METALIC STANDARD )
Earth :
Earth from borrow area is utilized for
road work suitable borrow area needs
to be demarcated
Moorum :
Good quality moorum needs to be
selected
Metal & Chips :
Metal & Chips of required size should
be utilised.
Bitumen:
As per specification should b utilises.
Steps followed for execution of road work
upto metallic standard
Step-1 :
Step-2 :
Step-3 :
Step-4 :
Step-5 :
Step-6 :
Inspection of Quarries
Collection of Certificates about quality of
source.
Collection of coarse, fine aggregates for
GSB, WBM and binding materials from
quarry.
Tests on coarse aggregate
Tests on GSB and binding materials (sand
gravel admixture)
If all the materials are OK allow these for
construction
Preparation of sub-grade:
Step-7:
Remove all vegetation and other extraneous matter from sub gradeLightly sprinkle with water if necessary – roll with two passes of 80 – 100
KN smooth wheel roller.
Step-8 :
Construction of Shoulder for Lateral confinement with approved material.
Granular sub-base:
Step-9 :
GSB material to be spread and rolled with 80 – 100 KN roller after
mechanical mixing (Manual mixing may be allowed if width of laying is
not adequate for mechanical mixing) – Smooth wheeled roller up to 100
mm compacted thickness and vibratory roller when compacted thickness
exceeds 100 mm. Rolling should commence from edges and progress
towards center and each pass of the roller shall uniformly over 1/3rd of
the track made in the preceding pass. The speed of the roller shall not
exceed 5 Km./ hour.
Step-10 :
Check cross fall (Camber) by template – spreading and rolling to
continue till appropriate cross fall is maintained and compaction is
achieved.
Carryout compaction test (98% compaction to be achieved)
Spread 23mm. course of screening (Grade – B) or coarse sand over the
prepared sub-base (Optional).
Step-11 :
Step-12 :
Water Bound Macadam:
Step-13 :
Spreading of coarse aggregate over prepared sub-base
uniformly and evenly.
Step-14 :
Checking with templates. All high and low spots to be remedied
by removing or adjusting aggregates.
Step-15 :
Dry rolling and checking with straight edge.
Step-16 :
Rolling with 80 – 100 KN roller shall begin from edges gradually
progressing towards center except for super elevation portion,
successive passes lapping uniformly preceding tracks by
approximately one half width.
Step-17 :
Rolling may be continued when aggregates are partially
compacted with sufficient void space in them to permit
application of screening.
Step-18 :
However when screenings are not applied as in the case of
crushed aggregates like brick metal, laterite and kankar,
compaction may be continued until aggregate are thoroughly
keyed.
Step-19 :
During rolling slight sprinkling of water may be done.
Step-20
Rolling shall not be done when the sub-grade is soft or yielding or
when it causes a wave like motion in the sub--grade or sub-base
course.
Step-21
The rolled surface shall be rechecked transversely and longitudinally
with templates and any irregularities corrected by loosening the
surface, adding or removing necessary amount of aggregates and
rolling
until
the entire surface conforms to the desired cross
fall and grade.
Step-22 :
In no case the screening shall be used to make up the depressions.
Step-23:
Materials which get crushed excessively during compaction and
become segregated shall be removed and replaced by suitable
aggregates.
Step-24 :
It shall be ensured that the shoulders are built up simultaneously along
with WBM.
Step-25 :
Application of screening materials spread uniformly in successive thin
layers to completely fill the interstices.
Step-26 :
Screening shall not be damp or wet at the time of application.
Step-27 :
Dry rolling should be done while screenings are being spread so that
vibrations of the roller cause them to settle into the voids of the coarse
aggregates. This shall be accompanied by brooming.
Step-28 :
The spreading, rolling and brooming of screenings shall be
carried out in only such lengths of the road which can be
completed in a day’s operation.
Step-29 :
After dry rolling, the surface shall be copiously sprinkled with
water, swept and roller.
Step-30 :
Hand brooms shall be used to sweep the wet screenings into
voids and to distribute.
Step-31 :
The sprinkling, sweeping and rolling operations shall be
continued with additional screenings applied a
necessary until the coarse aggregates have been toughly
keyed well bonded and firmly set in its full depth and grout has
been formed of the screenings.
Step-32 :
Care shall be taken to see that the sub-base or sub-grade does
not get damaged due to addition of excessive quantities of
water during construction.
Step-33 :
After application of screenings, binding materials where
required shall be applied in 2- 3 thin layers.
Step-34 :
After final compaction of WBM course, the pavement shall be
allowed to dry overnight and rolling and watering to continue till
slurry after filling voids forms a wave ahead of wheels.
Step-35 :
Next morning hungry sport shall be filled with
screening slightly sprinkled with water if necessary and
rolled.
Step-36 :
No hauling traffic may be allowed to use the completed
WBM course if in the opinion of the Engineer it would
cause excessive damage to the surface.
Step-37 :
The compacted WBM course should be allowed to
completely dry and set before next pavement course is
laid over it.
Step-38 :
The sequence of construction shall be such that the
construction of paved shoulder is none in layers
each matching the thickness of adjoining pavement
layer.
Step-39 :
Only after a layer of pavement and corresponding
layers in paved and earth shoulder portion have been
laid and compacted the next layer of pavement and
shoulder shall be taken up.
R O A D S:
Do
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Proper survey of the alignment is to be done. The L.S. and C.S.
should be drawn to proper scale and the final formation level is shown
superimposing on it.
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Detail drawing of C.D. work must be prepared with proper design at
proper chainage accompanying the estimate.
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The detailed estimate should accompany the report, abstract of
estimate, quarry chart Lead chart, Analysis of Rate, L.S. and C.S.
index map & Bar chart etc.
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In case of bridges, the estimate must be accompanied with reports,
L.S. and C.S. at 300m. U/S and D/S and at site showing HFL, OFL
and LWL,plan, water way calculation ,trial pit and other hydraulic
particulars. The report should also contain the detail designs, scopes,
rates, specifications, references, cost and mode of execution etc

In case of metalling road, the required quantity and quality of materials
is to be used.
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proper slope of 1:2 has to be maintained in the embankment.
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Earth work should be compacted with 10-12 T. roller exceeding 30
cm. in layer to achieve the maximum density.
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M.S.B. should be consolidated by laying not exceeding 23 cm. in
layer and compacted by the roller if necessary required amount
of water is to be added uniformly.
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The 1st coat metalling should be done with the locally available
stone metal of compacted thickness of 4”.
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The 2nd coat metalling should be done with black hard granite
metal of compacted thickness of 3”.
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The 2nd coat metalling should be covered up with B.T., otherwise,
do not go for 2nd coat metalling.
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Proper quality control measures has to be taken up by using
quality materials and following IRC specification.
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Provide drain wherever necessary. C.D. work and drain will be the
1st preference in case of road work.
DON’T
 Earth work computation should not be based on
pit measurement
 Don’t allow the work to be under compacted.
 Don’t use moist screening material to fill-up the
voids during metal consolidation
 Don’t go for 2nd coat metalling where there is no
provision of wearing course.
 Estimate should not be splitted-up in any
circumstances.
 Work should not be taken-up without
technically
sanctioned and administratively approved
estimate.
GUIDELINE FOR THE CONCRETE PAVEMENT

A bituminous road is damaged fast in high rainfall areas
due to poor drainage conditions,
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a gravel road becomes dusty, causing safety and health
problems due to a cloud of dust raised by motorised
traffic,

Problems of dust and wet weather damage to roads can
be easily overcome by constructing a thin flexible
concrete road using innovative technology at a cost
lower than that of a bituminous pavement for equal
traffic.
CONCRETE PAVEMENT - ADVANTAGE
Concrete roads have a large number of advantages over bituminious
ones. These advantages include:

Fuel Saving:Concrete
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Long Maintenance-Free Life:
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Gain in Traffic Speed:
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Resistance to Weather, Oil Spils, etc.:
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Economy in use of materials:
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Enviormental Friendliness:
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Use of Indigenous Materials:
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Other Advantages: These include better reflectivity.
CONCRETE PAVEMENT - ADVANTAGE
Concrete roads have a large number of advantages over bituminious
ones. These advantages include:
 Concrete roads, however, have one disadvantage vis-a-vas
bituminious ones, in that they are initially costlier to construct.
 with the price of bitumen going up steadily, and the use of fly ash
(available free from power plants) in making concrete mixes for
pavements now being accepted, the relative cost of these two types
of pavements could become quite comparable.
 When life-cycle costs are considered (as recommended by the BIS,
for all competing technologies), concrete pavements with their long
life and negligible maintenance, come out invariably superior to
bituminious ones.
 As regards the economic costs to the country, fuel saving and
environmental friendliness make concrete roads a far superior
choice over bituminous ones.
CONCRETE PAVEMENT : MATERIAL REQUIRED
A mixture of cement, water, fine and coarse aggregates
CEMENT:
 care must be taken to utilise fresh cement instead of old cement.
 Freshness can be checked in the bag itself since year and month
clearly indicated in the bag.
 machine stitched is needed to be checked.
 To ascertain the adulteration in cement if pinch of cement is dropped in
water, it will float in the water due to its super fineness or else it will sink
immediately.
 Type of Cement:
 i.
Ordinary Portland Cement
IS:269
 ii.
Rapid Hardening Portland Cement
IS:8041
 iii.
Portland Slag Cement
IS:455
 iv.
High strength ordinary Portland cement
IS:8112
 v.
Portland Pozzolana cement
IS:1489

Note: Use of Portland pozzolana cement may be permitted only in plain
concrete members.
WATER CEMENT RATIO:

Even though, basic requirement of water in cement mixture is very less but for
workability the water is added more. For example: Concrete M15, the water cement
ratio is approximately 42%.

Since, the water cement ratio serves as a yardstick for obtaining concrete of desired
strength the less the water greater the strength. But if more water is utilised, it
results excessive void, honey combs thereby reducing density, strength and
durability. So it must be prevented during execution.

Coarse aggregates: (to be utilised as per approved specification)
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Clean, hard, strong, dense, non-porous and durable pieces of crushed stone,
crushed gravel, natural gravel or a suitable combination.
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Shall not contain pieces of disintegrated stones, soft, flaky elongated particles, salt,
alkali, vegetable matte or other deleterious materials.
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Aggregate should not contain more than 5% of SO3.
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Use of higher size aggregate may lead to segregation.
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Aggregate impact value not exceeding 30% to reduce degradation of the aggregates
by crushing.
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The maximum size of coarse aggregate shall not exceed 25 mm. for pavement
concrete.
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No water absorption more than 2%.
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If the aggregates are not free from dirt, may be washed and drained for at least 72
hours.
Fine aggregates:
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Hard, strong, durable clean particles of natural sand, crushed stone or crushed gravel.
Shall not contain dust, lumps, soft or flaky particles , mica and other deleterious
materials in such quantities as would reduce the strength or durability of concrete.
Clean natural sand or crushed stone.
Water:
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Water used for mixing and curing shall be clean and free from injurious amount of oils,
acids, alkalis, salts, sugar organic materials.
Potable water is satisfactory for mixing concrete.
The maximum water cement ratio shall be 0.50.
Concrete:
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Measuring cement by weight.
Fine and coarse aggregates shall be by volume or by equivalent weight.
Mixing concrete:
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All concrete shall be machine mixed.
Until it is of even colour and uniform consistency throughout
Done for two minutes.
Mixed for immediate use.
Initially set cement shall not be used.
Initial set of ordinary Portland cement is 30 minutes after mixing.
Transporting concrete:
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Shall be transported as rapidly as practicable.
Prevent the segregation or loss of the ingredients.
Normally shall be completed within 30 minutes.
Avoid re-handling or flowing.
Placing and compacting concrete:
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Shall be placed before setting has commenced
Not be subsequently disturbed.
Shall be so placed as to avoid segregation.
Concrete shall not be dropped freely from a height of more than 2 metre.
Shall be thoroughly compacted.
Vibrators shall be used.
Vibrator should be kept until air bubbles cease escaping from the surface and
withdrawn slowly so that no hole is left.
Vibrators shall be inserted about 1.5 times the radius of the area visibly affected
by vibration.
Presence of 5% void reduce the strength by 30% and 10% void will reduce
60%
Construction joints:
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Concrete up to construction joints.
Shall be pre-determined (Length – 4.5m., Width – 3.5 m.)
Have sufficient lateral rigidity to prevent displacement or bulging.
Avoid dislodgement of coarse aggregates.
Hardened surface can be resumed after thoroughly hacked, swept clean,
wetted and covered with a layer or neat cement grout.
13mm thick layer mixed in same proportion in concrete
Use chairs to ensure cover.
Curing and protection of concrete:
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Kept constantly wet for a minimum period of 14 (fourteen) days.
Water be applied on unformed surface.
Concrete shall be kept constantly wet by ponding or covered with a layer of
sacking, canvas, hessian or a similar absorbent.
After placing concrete shall be protected from harmful effects of sunrays,
drying winds, cold, running water, shocks, vibrators, traffic including
construction traffic etc
FARM POND/ NEW POND
It is a small tank to store water essentially from surface run off.
 Also, affect regarding the flow if constructed in the catchment flow
such as WHS
 It helps irrigation. water supply to cattle, fish ,plantation
 It increases the ground water table
LOCATION
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It should be suitably finalised
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In the depression and valley
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For irrigation Purpose
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The site should be such that largest storage can be made with least amount
earth

Gravity out let should be provided
COMPONENTS OF FARM POND:
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Storage area
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Earthen embankment
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Mechanical spillway
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Emergency spillway
FARM POND/ NEW POND
Execution
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The area needs to be demarcated where the work is to be taken up
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Also, the area needs to be demarcated where the earth is to be
desposed of after excavation.
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The area needs to be marked with pegs on four site at a interval of
10-20 ft. so that by ting with rope on the opposite place, the level
(height) of execution at a particular point can be determined.

The earth work executed should be breaked to minimum of 4 cm.
size and to be laid with proper dressing as detailed given in the initial
stage.
Renovation of old pond:

The area needs to be demarcated for execution and dumping the
earth.

The pegs at an interval of 10 - 20 ft. on four sides should be placed
so that the level with the height of execution can be calculated by
tying rope in the peg on both side before execution as well as after
execution. The peg should be placed beyond the execution area.
Measurement procedure and rough calculation:
 The measurement can be done either through pit or through level
section.
 For pit measurement, the pits should be invariably of a standard size
i.e. 10ft.x10ftx1ft.
 The height can be 1ft., 2ft. and 3ft and it can be further multiplied to
evaluate the quantities.
 The pit should be numbered for each individual or group to avoid any
immediate error in assessing the quantities. These pits can be
measured for both side of the road work.
 As per level section (grid), the area where execution to be made needs
to be divided/demarcated in longitudinal and transverse direction at a
standard interval with pegging thereof.
 In the road alignment, the quantity can be ascertained on this fashion
so as to compare the quantity as per pit measurement.
 Immediate measurement the height can be achieved though the
witness (sakhi) kept by the labourers on the grid point for which the
tying of rope in a frequent manner can not be required.
TIPS ON BUILDING WORKS
1.
2.
3.
4.
Most of the areas are irrespective of black cotton soil or ordinary
soil of swelling nature which causes foundation failure and also
the swelling type of testing is very much simple and less costly
with involvement of only water and kerosene.
If the swelling type of soil is available then the said soil should be
replaced by course sand up to 1.5 D( where D is the width of the
foundation) with provision of ordinary foundation which prevents
shear crack.
Whenever the soil beyond 1.5 D is very poor in nature with low
SBC such as marine soil, such deep foundation like pile is to be
adopted.
Most of the time, the carriage contractor collects sand with silt as
ingredient causing damage to the building as sand mix silt/ clay
cracks and termite in the building which should be judiciously
checked.
BRICKS AND BRICK MASONRY
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1st class bricks to be used in the works conforming to the requirements of I.S:1077.
Strength of individual brick shall not be less than 7 Mpa (70kg/cm2)
Size shall be according to the local practice with tolerance of + 5%.
Bricks shall be free from cracks, organic matters, flaw and nodules of free lime.
Brick shall have rectangular faces with sharp corners.
Emit clear ringing sound when struck
Bricks of 190 mm x 90 mm x 90 mm or 230 mm x 110 mm x 70 mm shall be preferred.
Water absorption up to 20% by wt.
Bricks shall be stacked in regular tiers as they are unloaded to minimize breakage and defacement.
Bricks supply should be so arranged that at least two days requirements of Bricks are available at
site at any time.
Bricks selected for use in different types shall be stacked separately.
All bricks shall be thoroughly soaked in water for a minimum period of one hour before use.
Soaked bricks shall be removed from the tank sufficiently in advance so that they are skin dry at
the time of actual laying.
All bricks shall be laid in English Bond even and true to line.
All joints should be accurately laid. Joints in the successive courses of the brick work shall be
broken and the length of lap between the joints of the stretcher course with the header course shall
not be less than one fourth of the length of the brick.
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Brick bats or cut bricks shall not be used except to obtain dimension of different course.
All brick shall be laid with frog up on a full bed of mortar.
When laying bricks shall be slightly pressed so that the mortars gets in to all the surface pores
of bricks to ensure proper adhesion.
All joints shall be properly flushed and packed with mortar so that no hollow spaces left.
Brick works shall be laid in uniform layer, true to plumb or in specified batter.
No part of brick work shall rise more than one metre to avoid unequal settlement and
improper jointing.
Work shall be raked back to the bond and not toothed at an angle not steeper than 45º
Masonry work shall not be started earlier than 48 hrs. of casting of foundation Block.
Foundation Block shall be thoroughly hacked, cleaned, wetted and a layer of not less than 12
mm of mortar shall be spread to prepare the surface on which bricks will be laid.
In case of Rock, the surface shall be thoroughly cleaned and levelling course of M10 grade
with minimum average thickness of 150 mm shall be provided before laying the layer of
mortar.
In case of jointing with old masonry, the exposed joining surface shall be cleaned of all loose
materials, roughened and wetted with cement sherry to effect the best possible bond with the
new work.
All brick work shall be properly marked indicating the date of construction for keeping watch
for proper curing.
Masonry work in cement mortar shall be kept constantly moist on all faces for a minimum
period of seven days.
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The work with mortar which has become dry, white or powdery due
to neglect or curing shall be pulled down and rebuilt.
If any stain appears on the surface during watering shall be
removed.
Mortar shall be mixed such quantity as required for immediate use.
As a general guide, not more than half bag of cement shall be mixed
at a time if one mason is engaged.
The mix which has developed initial set shall not be used in the
works.
Retempering is permitted within initial setting time of 30 minutes.
Cement mortar unused for more than 30 minutes after addition of
water shall be rejected and removed from the site.
DO’S AND DONOT FOR BUILDING
DO
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Site for the project is to be selected and proper survey is done if
necessary
After survey to the site selected, the drawing i.e. plan, elevation
and section should be prepared to a proper scale indicating the
north point.
The S.B.C. of the soil should be determined.
Estimate should be prepared for the whole project which should
contain a report, detailed estimate, quarry
Chart, lead chart and analysis of rates.
Technical sanction and Administrative approval should be
accorded from the competent authority.
Structural components of the buildings should be properly designed
and care should be taken in case of bad nature of soil.
Care should be taken for execution of concrete work and curing
should be done for 28 days.
DO’S AND DONOT FOR BUILDING
DO

During placement of the reinforcement, attention should be given for
proper laying of the reinforcement at the support where there is (-ve)
bending moment. Proper cover to the reinforcement should also be
provided as per codal procedure.

Before taking-up the lintel, Chaija and roof slab, the centering and
shuttering must be checked properly.

Proper quality materials should be used for the work confirming to I.R.C/
I.S. and Orissa Standard Specification.

Prescribed water cement ratio should be followed.

Bearing plaster and tarpaper should be provided on the top of the wall
before casting of the slab.
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The estimate should contain the material component and labour
component to derive food grain component and their recovery.

In case of renovation, addition and alteration of the building, previous data
of the work should also be mentioned in the report.
DO’S AND DONOT FOR BUILDING
DON’T
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Infeasible project should not be taken-up.
Estimate should not be splitted-up in any
circumstances.
Work should not be taken-up without technical
sanction and administratively approved estimate.
Unreliable and locally produced cement and rod
should not be used.
Bad quality materials such as sand, chips etc. should
not be used.
Do not mix more water in concrete and mortar for
facilitating easy laying
Thanks …
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