Construction Quality & Safety Mangagment

Dr. C.RAJASEKARAN
Dept. of Civil Engineering , NITK
CV787-CONSTRUCTION QUALITY AND
SAFETY MANAGEMENT

Course Plan CV787
CV787- Construction Quality and Safety Management
Dr.C.Rajasekaran, Department of Civil Engineering, NITK
1. Course Code :
2. Course Title :
3. L-T-P :
4. Credits :
5. Subject Slot :
6. Course Instructor :
7. Teaching Dept. :
CV787
Construction Quality and Safety Management
3-0-0
3
E
Dr. Rajasekaran C
Civil Engineering
8. Objectives of the Course:
(i)
(ii)
(iii)
To give preliminary exposure to quality and safety management in construction industry
To improve the knowledge of safety laws and policies
To develop/formulate/execute some typical field problems and its solutions
9. Skill development expected from the course:
• Understand the basic principles of quality and safety management
• Ability to formulate and analyze the field oriented safety measures
• Ability to deal with practical quality and safety issues in construction industry
10. Evaluation Plan
Component Weightage
1. Mid-Sem Exam 25%
2. End-Sem Exam 50%
3. Seminar Presentations 10%
4. Attendance 5%
5. Assignments & Tutorials 10%

Outline of the course
Quality Management
1
Safety Management
2

Quality – Introduction
Quality means excellence.
It is thus a philosophy rather than a mere attribute.
The difference between two objects is judged by their
qualities.
We set some standards which determine the level of
acceptability.
In Construction Industry, in broader meaning Quality
as to any permanent should
structure
performance to the aesthetics, meeting
be to best
to the
specifications and is more relative.

Quality – Introduction
Old Concept New Concept
Technical Strategic
About the Products About Organizations
Led by Experts Led by Management
For Inspectors For Everyone
High Grade Appropriate improvement
About control About Improvement
About Specifications About Customer Satisfaction

QUALITY
IN
CONSTRUCTION
CLIENT
SATISFACTION
DOING A JOB
RIGHT THE FIRST
TIME
As per ISO 9000:2005 “Quality is the degree to
which a set of inherent characteristics fulfill
requirements”
CONFORMANCE
TO
SPECIFICATION
TIMELY
COMPLETION
Quality – A Definition

•Quality: conformance to established requirements (not a degree
of goodness).
• Quality activities: those activities in a project directly
associated with prevention and appraisal.
•Quality assurance: all those planned or systematic actions
necessary to provide adequate confidence that a product, process,
or service conforms to established requirements.
•Quality control: inspection, test, evaluation, or other necessary
action to verify that a product, process, or service conforms to
established requirements.

•Quality management: concerns the optimization of the quality
activities involved in producing a product, process, or service. As
such, it includes prevention and appraisal activities.
• Quality management costs: the sum of those costs
associated with prevention and appraisal activities.
•Quality performance management system: a management
tool providing data for the quantitative analysis of certain
quality-related aspects of projects by systematically collecting
and classifying costs of quality.

HIERARCHY OF QUALITY DEFINITIONS
Extra Features
It Develops
It Satisfies
It Works
A Mercedes Benz is a better
quality car than a Maruthi 800

Extra Features
It Works
It Develops
It Satisfies
“Conformance to requirements”
“Right the first time”

Extra Features
It Works
It Develops
It Satisfies
“Customer satisfaction”
“Fitness for use”
“Meeting customer expectations 100% of
the time”

It Satisfies
It Works
Extra Features
It Develops
Develop customers by educating them
and exposing them to greater value from
products and services

Quality - Limitations
 Limitation of Finance: This was the main factor of
construction and in every type of work where contractor
had to plan for financial payment to eliminate the risk
because it might affect the project.
 Limitation of Communication: Construction site
sometimes was located in rural areas or far away from the
community. It might be a cause which affected
transportation causing difficulty and delay, therefore it
was a limitation that contactor had to consider.

 Limitation of Labour and Wage: In many different local
areas, the problem related to labour such as lack of
skilled labour, complex work, not being able to find
labour might occur, which might be causes of work
difficulty, delay and low quality.
 Limitation of Weather: Weather was one of several
important limitations because it sometimes cannot be
prevented such as flooding, storm, etc.

 Limitation of Building Plan and Construction Detail:
Problems of building plan and construction detail were
found such as drawing not clear, drawing mistake, so they
also became big problems in construction.
 Limitation of Material and Equipment: Some construction
works might use special machines or equipment which
contractor had to study carefully regarding performances,
suitability for work and prepare enough equipment for
each work.
 Limitation of Time: Some construction works had to be
completed within a time limit such as in cases of urgent
works. They caned limitation of work planning and they
also caused other management problem. Therefore,
contractor had to carefully consider this issue.

 Limitation of Construction Methodology: Construction
works in some areas could not be performed by regular
method because
construction site,
there were buildings around
so the contractor had to find new
methods that were suitable to construct and sometimes
used specialist engineer when some construction works
were in step of construction.
 Limitation of Rule or Regulation: This problem also
greatly affected construction such as problem from traffic
which had an effect on transportation, problem of labour
hiring, problem of building construction regulation, etc.

 Training Policies: Looking into the general training policy,
the ISO 9001 registered companies have more concern on
the training of their employees than the nonregistered
ones. They not only pay for the course fees, but also allow
them to receive training during working hours. For non-
registered companies, the company may reimburse the
course
sessions
training
fees but employees
outside of working
programmes on
have to attend training
hours. Moreover, regular
technical and computer
knowledge were commonly provided in many companies.
The most popular training programme organized by ISO
9001 registered companies was Quality Knowledge.

 Lack of co-ordination among departments:
Coordination is very important for project successful.
Because co-ordination between the departments is
failed that may leads to wrong execution or may
affect the sequence of work. For example consider
the MEP (Mechanical Electrical Plumbing)
department not properly co-ordinate with execution
team, now execution team done the plastering work
before plumbing works are not done due to lack of
coordination. Here definitely rework required so
automatically quality is misplaced.
 Other Limitations: Such as cooperation of each party
that is related to construction project.

Quality Control– A Definition
Quality control means rational use of resources.
- It’s the process of initiating corrective action for errors,
developing systems to detect errors by faster, efficiently and
effectively and ultimately prevent errors from occurring.
Concrete quality control procedures implement:-
 appropriate mixing,
 proper compaction,
 correct placement and
 adequate curing.

Quality Control– A Definition
every stage of concrete
Quality control ensures:-
 strict monitoring of
production and
 rectification of faults.
 Quality control reduces maintenance costs.
Quality control prevents temptation of over design.

Concrete Quality Control
•The problem of quality is more complex for the concrete which
are placed In-Situ.
• Different players are involved in different stages of concreting
which makes the quality to be a complex phenomenon
•QC Stages
- Concept and Planning
- Detailed Design – (Drawings)
- Construction
- Maintenance
 Weigh Batching Vs Volume Batching
 Cleaning of Aggregates ( Should be free from dust oil, dirt etc and also should be SSD
 Priming Construction equipments
 Special situations like mixing manually, use of nominal mixes
 Temperature range for Normal Construction
 Method of transportation and necessary precautions
 Dosing of port of water and/or chemical admixtures during transportation or just before placing
 Formwork erection
 Storage of ingredients
 Batching of Ingredients
 Mixing of ingredients
 Transporting of concrete
 Depositing of concrete
 Compacting of concrete
 Joint making and finishing of concrete
 Curing of concrete
 Formwork removal and Patchwork

Mistakes....
Good
 Depth shall be till hard soil
 All around level shall be same
EXCAVATION
Bad
 Fixed depth
 Varying level all around

Mistakes....
Bad
o Varying depth
o Using bigger size aggregate
o Placing dry and pouring
water
o Dumping from the top
o No compaction
o Inadequate curing
Good
o Depth shall be equal all
around
o Mixing and placing
o Machine mixed
o Maintaining mix
o Properly placed
o Proper compaction
o Proper curing
PCC

Mistakes....
Good
o Uniform colour
o All edges straight
o Rectangular
o Uniform size
o Field tests
Bad
o Varying colour
o Half and broken
o Unburnt/ over burnt
o Varying size
o More porous

Mistakes....
Methods of soaking

Mistakes....
Conventional Method of Mixing of Cement Mortar
Proportions not
maintained
Sheet for mixing –
not used

Mistakes....
Conventional method of mixing cement mortar
No definite
boundary
Mixing not
proper
Ratio not
maintained
Water poured
much before use
Excess quantity
mixed – Initial
setting time
To be used
within 30 min.
of adding water

Mistakes....
Raking of Joints
Defective Joints

Mistakes....
Improper joints – Joints in one line

Mistakes....
Gap between Masonry and column

Mistakes....
Use Weigh Batcher instead of Pan
measure
Use of Measuring Box for Volume
Batching

Mistakes....
Mixer Machine operator without measuring Water
W/C ratio not
followed
More water –
More porous
concrete – less
durable

Mistakes....
Column steel not
restrained
Steel bars will
bend out of shape
Cover blocks to be
tied

Mistakes....
Steel placed
eccentrically
Load not
distributed
properly

Mistakes....
Column ties should fit the main
bars
Poor shuttering

Mistakes....
COLUMN TIES SHOULD FIT THE MAIN BARS

Mistakes....
- Steel not straightened
- Improper cranks
-Chairs between
reinforcements not
provided
-Cover blocks not
provided

Mistakes....
Cover block provided not appropriate
Pre Cast Cover blocks

Mistakes....
-Do not step over reinforcement
- No cover blocks

Mistakes....
IMPROPER PLACING OF CONCRETE (POURING FROM >1.5M)
RESULTING IN SEGREGATION

Mistakes....

Mistakes....
Pouring should be continuous from
one end to the other

Mistakes....
Trolley path

Mistakes....
Curing minimum four times a day

Mistakes....
Proper methods of
curing

Mistakes....
Improper conduit laying
Conduiting shall be vertical
Chipping not permissible – Chaising
should be with cutter

Mistakes....
Improper conduit laying

Mistakes....
Knowing the 20 mistakes occurs during construction phase ( for
planning purpose )
The cement sand mix in the mortar and brick masonry is made quite
early, prior to its use and in larger quantities than required.
The construction materials like sand, bricks, aggregate etc are not
washed and are full of deleterious material and dust.
Compaction of bottom strata in foundation work is not carried out.
During concreting of footing, the concrete is poured at a height
greater than 1m.
Generally, trapezoidal footings are resorted to where concrete is
never vibrated.

Mistakes....
Reinforced concrete column, being an important part of the
structure are neither mechanically vibrated nor machine mixed.
They are cast in short lifts with increased number of joints.
Cover to reinforcement in column, beams and slabs is insufficient.
No cover to reinforcement in contact of the ground.
Misalignment of column at foundation level and rectification at
higher level, leading to eccentric loading.
Reinforced coping at plinth level being an important barrier to
dampness is never densely cast.

Mistakes....
The plinth filling is never carried out in layers nor compacted.
At the joints of Reinforced concrete and brick masonry, either the
RC surface is not roughened or filling of mortar at the joint is not
evident.
The joint of brick masonry at larger height are improperly racked.
Mixing ratio in plaster and brick masonry is not maintained.
In the case where beams are cast prior to slabs :
In large slabs, the concrete in beams starts setting before
casting of RC slab.
The concrete spilled on the sides of beams while casting is
never removed which gets set subsequently

Mistakes....
Reinforcement of RC column is kept exposed above RC slab.
Hacking to concrete surface is poorly done prior to Plastering.
Bearing to lintels on both the ends is not sufficient.
In load bearing structure ,secondary beams are resting directly on
the walls giving point loading.
Proper care for uplift pressure in black cotton soil is not taken in
by proving with (i) Ground beam and (ii) Combined footing

Results of Mistakes....
The above construction mistakes may result in
 Cracks in concrete.
 Improper bonding between concrete and brick
masonry.
 Spillage of plaster.
 Dampness of walls.
 Leakage of slabs.
 Cracks in brick masonry.
 Settlement of foundation and walls.

Causes of Mistakes....
Causes for poor quality can be summarized as
ignorance,
poor materials,
poor design,
poor detailing,
poor workmanship,
improper quantity of cement,
improper concrete mix,
excess water,
inadequate compaction,
substandard forms,
inadequate curing,
inadequate cover,
 poor construction practices,
poor supervision and above all lack of technical
knowledge.

Concrete Quality Chain
Cement : Type and Quantity
Aggregate: Quantity & Grading
Water: Quantity & Quality
Material Storage
Fixing Formwork
 Reinforcement
 Batching
 Mixing
 Transporting
 Placing
Compacting, Joint Making &Surface Finishing
 Curing
 Formwork Removal
 Final Finishing
 Quality check for Fresh concrete

Concrete Quality Control - Aim
The main aim of implementing quality control
procedures is to provide:-
 Durability
 Strength
 Impermeability
 Workability
 Dimensional stability
 Good appearance
 Water content
 Economy.

Durability
o Durability at any price and “reasonable” durability of
economical concrete.
o More particularly there is a difference between the
and the durability of
durability of plain concrete
reinforced concrete.
o The nature of modern cements is often blamed.
o Greater strength efficiency of new cements should lead
to the increased use of supplementary cementitious
materials rather than an increased water/cementitious
ratio.
viewpoint of
is from the
o Curing is more important from the
durability and impermeability than it
strength viewpoint

Strength
o A primary criterion of concrete quality.
o Its resistance to rupture.
o It may be measured in a number of ways such as ,
strength in compression, in tension or in flexure.
o Mix design has generally meant designing a mix to
provide a given strength.
For a given cement and acceptable aggregates, the
strength that may be developed is influenced by
(a) Ratio of cement to mixing water
(b) Ratio of cement to aggregate
shape, strength and
(c)Grading, surface texture,
stiffness of aggregate particles
(d) Maximum size of aggregate

Impermeability
o Water is the worst component of concrete from the
permeability viewpoint (after setting).
o Curing is more critical for impermeability than it is
for strength.
o There are three avenues by which water can
penetrate concrete
1. Gross voids arising from incomplete compaction,
often resulting from segregation.
2. Micro (or macro) cracks resulting from drying
shrinkage, thermal stresses or bleeding settlement.
3. Pores or capillaries resulting from mixing water in
excess of that which can combine with the cement.
That is water in excess of 0. 38 by mass of cement.
o Bleeding

Workability
 Workability is a critical feature of most concrete
and there is much more to this property than is
revealed by the still widely used slump test.
 Apart from slump, workability may include some or
all of mobility, fluidity, pumpability, compactability
and, negatively, segregation and bleeding.
 A factor other than water content is clearly
involved and this is best described as cohesion

Dimensional stability
 Dimensional stability may include undesirable degrees
of thermal expansion and also disruptive expansion due
to alkali-aggregate reaction or sulfate attack but
essentially the problem is shrinkage.
 Autogenous shrinkage is relatively recently recognized
as a phenomenon as it relates to concretes of very low
w/c ratios which shrink as a result of self desiccation.
 Drying shrinkage is a result of contraction of the
cement paste as the uncombined excess water
evaporates.
 From this it is obvious that shrinkage will be higher if
there is more water and cement and more sand.

Water Content
 A low w/c ratio still means better concrete
 The mix with the lowest cement content is the best
concrete, since it has the lowest total water
content.
 The water content at a given slump increases as
concrete temperature increases, is unknown or
disregarded by typical specifications, so that a
higher slump concrete on a cold morning may be
rejected when a lower strength concrete may be
accepted on a warmer afternoon.

Good Appearance
 A good appearance requires that concrete be fully
compacted and free from ‘bug holes’ Actually the
type of formwork and the mould oil used may have
a considerable effect on this aspect.
 A tendency to bleed allows water to travel up the
face of the formwork or towards any slightly
leaking joints.

Economy
 The most expensive concrete is that which has to
be replaced due to being either initially
unsatisfactory or inadequately durable.
 The cost of a higher quality grade of the concrete
itself is, in most cases, a relatively small proportion
of the total cost of the final structure.
 However it should be borne in mind that the
additional cost of a slightly higher quality concrete
can be a significant proportion of the concrete
producer’s profit margin

Economy
The main cost factors are:
 Unit costs of materials
 Ability to design economical mixes
 Control margin (necessary difference between
specified and mean strength)
 Expenditure on staff, equipment and software
 Efficiency of operation
The correct choice of materials shall be made taking
into account the variability of those materials, which
can increase costs by increasing concrete variability
and therefore the necessary control margin.

Overall Checklist before commencing concreting
Sl No Items Action
1. Final Levels and lines of centering are checked Yes/No
2. Reinforcement and centering approved by the engineer-in-charge Yes/No
3. Cover blocks for reinforcement provided Yes/No
4. Necessary tightening of supports and bracing completed Yes/No
5. Required quantities of cement, metal and sand (approved quality) for the day’s
work brought to site
Yes/No
6. If construction joint is planned, necessary stop board prepared and brought to site Yes/No
7. Concrete mixer and vibrator with operators and mechanic available Yes/No
8. Necessary wooden benches for walking over slab reinforcement available Yes/No
9. Water-cement ratio fixed and measuring can for water available Yes/No
10. Supervisor at mixing point detailed with sufficient briefing to ensure production of
quality concrete
Yes/No
11. Cube moulds for making test cubes and slump cone kept ready Yes/No
12. Bulkage test is conducted and the % of bulkage decided for sand Yes/No
13. All inserts to be embedded in concrete are checked and placed in position including
electrical conduits
Yes/No

Common Problems and remedies - CQC
No. Defect Cause Suggested solution
1 Segregation
and bleeding
 Mix is lean Use richer mix
Over vibration Avoid over vibration
2 Permeability
and
shrinkage
High water
content in the mix
Reduce water cement
ratio
Lack of
compaction
Resort to sufficient
compaction
Improper grading
of aggregate Use upper graded
aggregate

3 Blow holes
on exposed
faces
Improper mix design
Use correct water cement ratio.
Use air entraining to improve
workability if the water-cement
ratio is to be kept low
Inadequate cover
between reinforcement
and mould face which
restrains local flow of
concrete between them.
Use adequate
reinforcement
cover for
Use larger and cubical coarse
aggregate and sufficient sand
Lack
vibration
of sufficient
Resort adequate mechanical
vibration using vibrator head of
larger circumference.
Resort to knifing at the contact
face of mould
Resort to vigorous tamping
with a wooden mallet on all sides
of formwork as the concreting
proceeds.

Dr.C Rajasekaran, Department of Civil Engineering, NITK
4 Plastic
cracks(small,
near
horizontal
cracks at
faces)
During compaction higher particle
tend to settle down and water rises
up and collects below certain points
of concrete, remaining higher due to
arching or interlocking. This causes
cracks during drying below such
points.
Use cohesive mix
Place and compact
concrete in layers, avoiding
any local points of arching
5 Crazing(map
of fine cracks
on the
surface up to
3 cm long)
Shrinkage of surface due to surface
carbonation(caused due to the
reaction of free lime released during
hydration with CO2. Which reduces
the resistance of the surface to
drying shrinkage)
Reduce water cement ratio
Use pozzolona cement
Resort to membrane
curing and keep the surface
covered.
6 Efforescence(
white
patches)
High water-cement ratio Reduce water cement ratio
Large quantity of free lime
released during hydration.
Use pozzolona cement
7 Spalling Use concrete of low strength Use concrete of sufficient
strength
Form lining is not absorbent Use absorbent form lining
.

8 Cement not
hardening
Cement used is slow setting Use cement of
appropriate setting time or
use accelerators
Cement used is adulterated In case of suspected
adulteration, carry out
necessary field tests to
ascertain whether the
cement is adulterated or
not, prior to using it in the
work
9 Loss in
workability
and mix
becoming
harsh
 Evaporation of moisture in
concrete, which is required
for hydration: due to
severe temperature
conditions coupled with
wind
In case of initial setting
time has not lapsed, the
concrete may be tempered
with by adding little
quantity of water having
regard to the water-cement
ratio and then mixing
before use.
Improper grading or
insufficient cement sand
mortar in the mix

Quality Control - Fck
Testing of Compressive strength, as a parameter for quality control,
requires us to address the following:
- Sampling Frequency and method
- Samples by volume of pour
- Samples by time
- Location of sampling ( plant, site – agitator truck,
discharge pipe etc)
- Testing method
- Nature and size of the specimen
- Storage of the specimen before testing
- Testing methodology
-Equipment to be used, Rate of Loading, Condition of the
specimen at the time of testing.
- Acceptance criteria
The basis of acceptance is of which it can be stated that the
concrete meets the requirements and hence it is “Accepted” , and a
corollary, failing which the concrete may not be “Accepted”.

Quality Control - Fck
Consideration in Defining the Acceptance Criteria
- Characteristic Strength
- Reasonableness in criteria and decision making
-Lay down and define an unambiguous flow-chart to
follow
- Number of specimens to obtain a representative
value
-How to handle the “Non – acceptance”

Recommendations of IS: 456 - 2000
Sampling Procedure
Quantity of Concrete Work
(m3)
No. of Samples
1- 5 1
6-15 2
16-30 3
31-50 4
51 and above 4 + one additional sample for each
additional 50 m3 or part there of

Quality Control – Materials -Cement
Tests IS Code Ref. Requirement Frequency
Fineness
IS:12269:1987
& IS 3535, IS 4031
Retention Not more than
10%
Every Load
Shelf Life
Shall not be more than 3
months from the D O M
Every Load
Consistency
3, 7 , 28 days Compressive
strength results
Every Load
IST and FST
IST - Not < 30 minutes
FST - Not > 600 Minutes
1 sample per Brand per
Fortnight
Compressive Strength
3 Days not < 27 N/mm2
1 sample per Brand per
Fortnight
Chemical Properties
As per Table -1 of IS: 12269 -
1987
1 sample per Source

Quality Control – Materials -Aggregates
Gradation
IS: 383-1970
As per 383-1970 Every New Source
Water Absorption
As per Table -2 of IS:383 -
1970
Once in Every 3 loads
Specific Gravity -
Once in 3 Months
inclusive of all Sources
Chlorides and Sulphates -
Once in 3 Months
inclusive of all Sources
Moisture content As per 383-1970 Once per Source

Quality Control - Materials
Flyash
Fineness IS: 3812(pt-1)
Residue shall Not be > 34%
( by wet sieving)
Every load
Water
All parameters such as
Alkalinity, Hardness, pH - as
per IS 456
IS: 456 - 2000
As per Table 1 of IS: 456 -
2000
For every New Source
Admixture
Uniformity Requirements IS : 9103 : 1999
As per Table 2 of IS : 9103 -
1999
For every new source

Quality Control – Materials - Steel
Tensile Strength
IS: 1786:2008
Not Less than 545
N/mm2
500MT once
0.2% Proof Stress/Yield
Stress
Min 500 N/mm2
Min 12%
Percentage Of Elongation
Unit Weight
Up to and
including10mm dia
( -8%), over 10mm up to
and including 16mm (-
6%) ,Over 16mm (-4%)
For individual samples
Bend & Rebend Test
There should be no
rupture/Crack in the
bent Portion
Chemical Properties
As Per the table in Clause
4.2 of IS: 1786:2008
1000MT once

Acceptance Criteria:
IS:456-2000 stipulates the following conditions for cube compression strength
compliances:
(a) The mean strength determined from any group of four consecutive test
results complies with the appropriate limit in the second column of Table..
(b) Any individual test result complies with the appropriate limit in the third
column of Table.
Specified Grade Mean of the group of four non –
overlapping test results (N/mm2)
Individual test
result (N/mm2)
M15 ≥ fck + 0.825S (rounded to nearest 0.5) or
fck + 3, whichever is larger
≥ fck - 3
M20 and above ≥ fck + 0.825S (rounded to nearest 0.5) or
fck + 4, whichever is larger
≥ fck - 4

Target mean 28-day compressive strength (fck):
fck = fck + t × s
where
fck is the desired characteristic 28-day compressive strength,
s is the standard deviation (Table 1) and
t is a tolerance factor that depends on the accepted proportion of low
results and the size of the sample.(Table 2)
For 95% certainty that the result will not be less than fck, t is taken as 1.65.
For other proportions of acceptable low values, t-values are provided in a
table. Also, in the absence of test results, standard deviation values are
suggested in another table (e.g., M30 concrete, with good degree of control,
s can be taken as 6 MPa).

Grade of concrete Assumed Standard
Deviations (N/mm² )
M 10 ,M 15 3.5
M 20, M25 4.0
M 30, M 35, M 40,
M 45 & M 50
5.0
Table 1: Assumed Standard Deviations from Table 8 of IS:456-2000

Typical values of the Standard Deviation for Different
Conditions of Placing and Mixing Control

Table 2: Values of Tolerance Factor (t) ( Risk Factor)
Accepted proportion of
low results
t
1 in 5, 20% 0.84
1 in 10, 10% 1.28
1 in 15, 6.7% 1.50
1 in 20, 5% 1.64
1in 40, 2.5% 1.96
1 in 100, 1% 2.33

Contractor’s Quality Control Plan
Appoint a responsible person
Ensure the expertise , experience, independece and impartiality
of responsible person
Submit a rough concrete design
The Contractor's documentation procedures will be subject to
approval of the Engineer before the start of the work and to
compliance checks during the progress of the work.

Site Engineer’s Quality Control Plan
Ensure or prepare correct and detailed design documentation.
Documentation include the quality and reliable performance
Design the technical documentation (site use only)
Preparatory work (planning)
Scraffolding and form work (before and after casting)

CQC - Improvements
 A detailed study of project documentation
 Aligning of the potential doubts before the start of
concrete works
 Quality assurance performance of reinforced concrete
structures
 Document and define all activities within the process
 It is necessary to hire professional
 Planning and providing training for all the participants
whose work affects quality
 Defining a procedure to eliminate non-compliance
performance
 Creating a concrete quality performance plan that will
elaborate the performance of the construction in
accordance with the available resources and organizations.

Concrete formwork
From the viewpoint of inspection, two factors are primary:
safety and finish
 During the placing of the concrete and development of
initial set, safety is of the greatest importance, and
deserves total emphasis
 After removal of the formwork, finishing has to be taken
care of

 Check location of forms
 Check interior condition of forms for soundness and
proper surface finish
 Check form supports for conformance with form drawings
and basic soundness
 Check shoring and bracing in accordance with the shoring
list
 Check for grade and soundness in formwork made of
reused lumber
 Form should be wet down prior to use to swell them
 Forms should be cleaned out before pore
 Where form ties are used, check installation and number
Checklist – Concrete Formwork

 Metal forms should be oiled rather than wetted, but
surplus oil should not be on the formwork
 Steel reinforcement is to be placed within forms in
accordance with rebar drawings. Count the numbers and
check sizes
 Reinforcing bars should be supported by chairs or is
permitted by specifications, concrete blocks to hold them
the proper distance away from the outside face of the
concrete
 Where the final surface will be exposed, specifications
usually call for plastic, galvanized tip, or stainless steel
chairs or accessories to avoid rust marks
Checklist – Concrete Formwork

 Check forms and rebar
 Be sure that concrete is in accordance with design mix,
certified id required
 Inspect at batching plant if required
 Check time of receipts for ready mix, amount of water
added, if permitted, and mixing time
 Be sure trucks do not overstay maximum waiting
period before placing of concrete, usually less than an
hour
Cast-in-place Concrete - Checklist

 Be sure that placement is in accordance with
specifications
 Concrete should be dropped only the allowable distance,
and should not bounce across reinforcing bars or other
obstructions causing segregation
 Be sure that appropriate slump and air content tests are
taken as required
 Concrete should be vibrated as it is placed, and vibrators
should not hit the reinforcing bars or the forms. Concrete
should be worked either with a float or a troweled finish,
as required by the specifications

 Curing compound should be placed on finished
concrete, unless it is under a floor to be tile covered
 Concrete should not be placed after initial set has been
reached, and should not be remixed after initial set
 Screed boards are often utilized to assure the proper
grade of finished concrete
 Be sure that test cylinders are taken and handled
carefully. They should be stored under job conditions

 Check mix versus approved mix design
 Check truck time from start of mixing
 Take slump test if required
 Take air test for air entrained concrete
 Take concrete cylinders, and:
 Mix and fill cylinders
 Rod carefully
 Strike off and tap to close voids
 Cure under job conditions
 Check test results at 3 or 7 days and confirm at 28 days
Concrete Test- Checklist

Cost of Quality Control
The Quality cost breakdown is based on the work of
Feigenbaum (1983), who first developed the concept
in (1956).
Quality costs = Quality control cost + Failure cost
Where,
Quality control cost = Prevention cost + Appraisal cost
:and:
Failure cost = Internal failure costs + External failure cost

QMS – Cost of Quality
COST OF
QUALITY
APRAISAL COST
EXTERNAL FAILURE COST
INTERNAL FAILURE COST
PREVENTION COST
MEASUREMENT AND
TEST EQUIPMENT

Cost of Quality Control
The relationship between cost and quality level is also shown
pictorially and is self explanatory.

PDCA - CYCLE

Quality Management Activities for Design and Construction
• Quality system development
• Quality program development
• Feasibility study
• Contractor / subcontractor evaluation
• Quality orientation activities
• Personnel qualification / testing
• Personnel training
• Formal design check / review *
• Formal drafting check / review *
• Formal check / review of other documents *
• Constructability review *
*
• Materials inspection / tests
• Inspection *
• Quality status documentation
• Post-project review
* When repeated, the cost of these activities become deviation costs

References
 Concrete, S. Mindess and J.F. Young, Prentice-Hall, USA, 1981
 Properties of Concrete, A.M. Neville, Pearson Education, Delhi,
2004
 Concrete Technology Theory and Practice, M.S. Shetty,
S.Chand, 2014.
 Concrete Construction Handbook, Joseph A. Dobrowolski,
Mcgraw-Hill Handbooks, 1998
 Concrete Technology, A.R. Santhakumar, Oxford , 2014
 Concrete Mix Design, Quality Control and Specification, Ken W.
Day, Taylor & Francis, 2006.
 The Science and Technology of Civil Engineering Materials, J.F.
Young, S. Mindess, R.J. Gray and A. Bentur, Prentice Hall, 1998
 Concrete: Microstructure, properties and materials, P.K.
Mehta and P.J.M. Monteiro, Indian Concrete Institute, Chennai,
1999

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