CONTENTS
1. INTRODUCTION
2. SELECTION OF PLOT AND STUDY
3. SURVEY OF SITE FOR PROPOSED BUILDING
4. BUILDING BYE LAWS AND REGULATIONS
5. ORIENTATION
6. DETAILS OF COLUMN
7. DETAILS OF BEAM
8. DETAILS OF FOOTING
9. DETAILS OF FOUNDATION
10. DETAILS OF SLAB
11. DETAILS OF STAIRCASE
12. DESING CRITERIA FOR SLAB & BEAM
13. CONCLUSION
INTRODUCTION
I performed
most of the same duties which a civil engineers performs as a civil engineer,
only under supervision of a licensed, registered, experienced civil engineer.
The purpose of a civil engineer trainee position is to train a newly graduated
and licensed engineer how to correctly perform all job duties while in a safe
environment that allows for guidance and learning.
I learned how
to analyze any situation and take correct decisions, take field tests, to adopt
safety measures, and research in order to complete engineering projects that
are limited in scope. As experiences grows, so do the complexity of tasks,
while supervision diminishes.
SELECTION OF PLOT AND
STUDY
Selection
of plot is very important for buildings a house. Site should be in good place
where there community but service is convenient but not so closed that becomes
a source of inconvenience or noisy. The conventional transportation is
important not only because of present need but for retention of property value
in future closely related to are transportation, shopping, facilities also
necessary. One should observe the road condition whether there is indication of
future development or not in case of un developed area.
The
factor to be considered while selecting the building site are as follows:-
• Access to park
&playground.
• Agriculture polytonality of
the land.
• Availability of public utility services, especially
water, electricity & sewage disposal.
• Contour of land in relation
the building cost. Cost of land .
• Distance from places of
work.
• Ease of drainage.
• Location with respect to
school, collage & public buildings.
• Nature of use of adjacent
area.
• Transport facilities.
• Wind velocity and direction.
SURVEY
OF THE SITE FOR PROPOSED BUILDING
Reconnaissance survey :- The following has been observed during reconnaissance survey of the site.
•
Site is located nearly.
• The site is very clear planned without
ably dry grass and other throne plats over
the entire area.
•
No leveling is require since the land is must uniformly level.
•
The ground is soft.
•
Labour available near by the site.
• Houses are located near by the site.
Detailed survey :- The detailed
survey has been done to determine the boundaries of the required areas of the
site with the help of theodolite and compass.
BUILDING
BYE LAWS & REGULATIONS
• Line
of building frontage and minimum plot sizes.
• Open spaces around hospital building.
• Minimum standard dimensions of building elements.
• Provisions for lighting and ventilation.
• Provisions for safety from explosion.
• Provisions for drainage and sanitation.
• Provisions for safety of works against hazards.
• Requirements for off-street parking spaces.
• Requirements for landscaping.
• Size of structural
elements.
ORIENTATION
After having selected the
site, the next step is proper orientation of building. Orientation means proper
placement of rooms in relation to sun, wind, rain, topography and outlook and
at the same time providing a convenient access both to the street and back
yard.
The factors that affect
orientation most are as follows.
• Solar heat
• Wind direction
• Humidity
• Rain fall
• Intensity of wind site
condition
• Lightings and ventilation
SOLAR
HEAT :- Solar heat
means sun’s heat, the building should receive maximum solar radiation in winter
and minimum in summer. For evaluation of solar radiation, it is essential to
know the duration of sunshine and hourly solar intensity on exposed surfaces.
WIND
DIRECTION :- The
winds in winter are avoided and are in summer, they are accepted in the house
to the maximum extent.
HUMIDITY :- High humidity which is common phenomenon is in coastal
areas, causes perspiration, which is very uncomfortable condition from the
human body and causes more discomfort.
RAIN
FALL :- Direction and intensity of rainfall effects the
drainage of the site and building and hence, it is very important from
orientation point of view.
INTENSITY
OF WIND :- Intensity of
wind in hilly regions is high and as such window openings of comparatively
small size are recommended in such regions.
SITE
CONDITIONS :- Location of
site in rural areas, suburban areas or urban areas also effects orientation,
sometimes to achieve maximum benefits, the building has to be oriented in a
particular direction.
LIGHTING :- Good lighting is necessary for all buildings and three
primary aims. The first is to promote the work or other activities carried on
within the building. The second is to promote the safety of people using the
buildings. The third is to create, in conjunction to interest and of well
beings.
VENTILATION :- Ventilation may be defined as the system of supplying
or removing air by natural or mechanical mean or from any enclosed space to
create and maintain comfortable conditions. Operation of building and location
to windows helps in providing proper ventilation. A sensation of comfort,
reduction in humidity, removal of heat, supply of oxygen is the basic
requirements in ventilation apart from reduction.
PLAN
GENERAL SPECIFICATION
GROUND AREA :- 1516.38Sq.M.
FIRST FLOOR AREA :- 1345.62Sq.M.
SECOND FLOOR AREA :- 1345.62Sq.M.
TOTAL BUILT UP.AREA :- 6898.86Sq.M.
FOOTING :- R.C.C. FOOTING &
FOUNDATION.
STRUCTURE :- R.C.C. FRAMED STRUCTURE.
WALL :- CHIMNEY BURNT BRICKS/C.R . MASONARY.
ROOF :- R.C.C. FLAT & SLOPING
ROOF WITH WATER- PROOF TREATMENT.
FLOORING :- FLOORING/LOCAL SAND STONE.
DOOR PANEL :-
35 MM
THICK FLUSH DOOR.
DORMITORY DOORS :-
35 MM
TH. FLY –INESH SHUTTER.
FITTINGS :- M S FITTINGS ON
DOORS/WINDOWS .
WINDOW PANELS :-
4 MM THICKNESS
CLEAR GLASS PANEL
OUTSIDE WITH Z-SECTIONS.
FRAME :- FLY-PROOF SHUTTER INSIDE
FITTED IN 20
MM THICKNESS JUNGLE WOOD
BATTEN/M.S. FLATS.
VENTILATORS :- HONEY –COMB MASONARY VENTILLATORS.
RAILING :- M.S RAILLING
APPROVED.
PAINTS :- ENAMEL PAINT ON
FRAME OF DOOR/WINDOW/GRILL ETC
OF APPROVED COLOUR.
WARDROBES :-
20-25
MM THICKNESS STONE
SHELVES,SHUTTER SOLID CORE
WITH ALUMINIUM FITTINGS.
ANTI –TERMITE TREATMENT :- IN WHOLE BUILDING
SANITARY-WARE :-
C.P. FITTINGS,
CI/SW PIPES FOR SANITARY
WATER –SUPPLY TANK :- G.I. PIPE
FOR WATER SUPPLY
HDFF (SINTEX) WATER TANK.
VIEW OF WORKING BUILDING
R.C.C. RECTANGULAR COLUMN
FORMWORK (AS PER I.S.
456:2000)
NECESSITY OF FORMWORK :-
THE FORMWORK SHALL BE DESIGNED AND
CONSTRUCTED SO AS TO REMAIN SUFFICIENTLY RIGID DURING PLACING AND COMPACTION OF
CONCRETE AND SHALL BE SUCH AS TO PREVENT LOSS OF SLURRY FROM THE CONCRETE.
CLEANING AND TREATMENT OF FORMWORK :-
THE FACE OF FORM WORK IN CONTACT WITH
THE CONCRETE SHALL BE CLEANED AND TREATED WITH FORM RELEASE AGENT. RELEASE
AGENTS SHOULD BE APPLIED SO AS TO PROVIDE A THIN UNIFORM COATING TO THE FORM
WITHOUT COATING THE REINFORCEMENT.
STRIPPING TIME:-
FORM SHALL NOT BE RELEASED UNTILL THE
CONCRETE HAS ACHIVED A STRENGTH OF
ATLEAST TWICE THE STRESS TO WHICH THE CONCRETE MAY BE SUBJECTED AT THE TIME OF
REMOVAL OF FORMWORK.
STRIPPING TIME
S.NO
|
TYPE OF FORMWORK
|
MINIMUM PERIOD BEFORE STRIKING FORMWORK
|
(1)
|
VERTICAL FORMWORK TO
COLUMNS
|
16-24 hr
|
(2)
|
SOFFIT FORMWORK TO SLAB
|
3 DAYS
|
(3)
|
SOFFIT FORMWORK TO BEAM
|
7 DAYS
|
(4)
|
PROPS TO SLAB
SPANNING UPTO 4.5 M
SPANNING ABOVE 4.5 M
|
7 DAYS
14 DAYS
|
(5)
|
PROPS TO SLAB
SPANNING UPTO 6 M
SPANNING ABOVE 6 M
|
14 DAYS
21 DAYS
|
CONCRETE MIX PROPORTIONING MIX PROPORTION:-
(AS PER I.S. 456:2000)
THE MIX PROPORTIONS SHALL BE SELECTED
TO ENSURE THE WORKABILITY OF FRESH CONCRETE AND WHEN CONCRETE IS HARDENED, IT
SHALL HAVE THE REQUIRED STRENGTH, DURABILITY AND SURFACE FINISH.
THE DETERMINATION OF CEMCENT, SAND,
AGREEGATE & WATER TO ATTAIN THE
REQUIRED STRENGTHS SHALL BE MADE AS FOLLOW-
(A)
BY DESIGNING THE
CONCRETE MIX; SUCH CONCRETE SHALL BE CALLED ‘DESIGN MIX CONCRETE’.
(B)
BY ADOPTING NOMINAL
CONCRETE MIX; SUCH CONCRETE SHALL BE CALLED ‘NOMINAL MIX CONCRETE’.
STANDARD VALUES OF DIFFERENT ITEMS OF CONCRETE
(AS PER IS 456 : 2000)
GRADE
OF CONCRETE
|
PROPORTION
|
TOTAL QUANTITY OF DRY AGREEGATES
BY MASS PER 50 kg OF CEMENT
|
PROPORTION OF FINE AGG TO COARSE
AGGREGATE
|
QUANTITY OF WATER PER 50 kg OF
CEMENT
(lit)
|
M5
|
1:5:10
|
800
|
GENERALLY
1:2 BUT SUBJECT TO AN UPPER LIMIT OF 1:1½
AND A LOWER LIMIT OF 1:2½
|
60
|
M7.5
|
1:4:8
|
625
|
45
|
|
M10
|
1:3:6
|
480
|
34
|
|
M15
|
1:2:4
|
330
|
32
|
|
M20
|
1:1 ½:3
|
250
|
30
|
NOTE :- ( IN ABOVE TABLE “M” SHOWS MIX DESIGN & 5,10,15,20,25 SHOWS THEIR
CHARACTERISTIC COMPRESSIVE STRENGTH OF CONCRTE IN 28 DAYS)
IMPOSED FLOOR LOADS FOR
DIFFERENT OCCUPANCIES
(AS
PER IS 456:2000)
S.NO
|
OCCUPANCY CLASSIFICATION
|
UDL (KN/m2)
|
CONCENTRATED LAOD (KN)
|
1.
|
RESIDENTIAL
BUILDINGS
(I) DWELLING HOUSES
(ii) HOTELS, HOSTELS, BOARDING HOUSES, RESIDENTIAL CLUBS.
(III) STORE ROOMS
(IV) GARRAGES
(V) BALCONIES
|
2.0-3.0
2.0-4.0
5.0
2.5-5
3
|
1.8-4.5
1.8-4.5
6.7
9.0
1.5
|
2.
|
EDUCATIONAL BUILDINGS
(I) CLASS ROOMS, RESTAURENTS, OFFICES, STAFF ROOMS,
KITCHENS, TOILETS.
(II) STORE ROOMS.
(III) READING ROOMS.
(IV) CORRIDORS, LOBBIES.
|
2.0-3.0
5
3.0-4.0
4.0
|
2.7
4.5
4.5
4.5
|
3.
|
BUISNESS & OFFICE BUILDINGS
(I) BANKING HALLS
(II) RECORD ROOMS/ STORE ROOMS
|
3.0
5.0
|
2.7
4.5
|
4.
|
MERCANTILE BUILDINGS
(I) RETAIL
SHOPS
(II) WHOLESALE SHOPS
|
4.0
6.0 (MIN)
|
3.6
4.5 (MIN)
|
5.
|
INDUSTRIAL BUILDINGS
(I) WORK AREAS WITHOUT MACHINERY / EQUIPMENT.
(II) CORRIDORS, PASSAGES, STAIRCASE.
|
2.5
4.0
|
4.5
4.5
|
6.
|
STORAGE BUILDINGS
(I) STORAGE ROOMS
(II) BOILER ROOMS & PLANT ROOMS
|
2.4 KN/M2 PER EACH METRE OF STORAGE HEIGHT WITH A MIN OF
7.5 KN/M2
7.5
|
7.0
4.5
|
FRONT ELEVATION
 |
FLY ASH BRICK WALL CONSTRUCTION
CASTING OF COLUMN
LAYING OF REINFORCEMENT FOR STAIR LANDING
SHUTTERING WORK FOR SLAB
GENERAL SPECIFICATION
FOR GROUND FLOOR
(TOTAL AREA = 1516.38 Sq.M)
FLOORING :- KOTA STONE, CERAMIC GLAZED, PAVER BLOCK, CHEQUERRED
PRECAST CEMENT CONCRETE TILES, CEMENT BASED WATER PROOFING.
SKIRTING :- KOTA STONE.
WALLS :- PLASTIC EMULSION PAINT, CEREMIC GLAZED.
CEILING :- DIS-TEMPERING WITH OIL BOND.
DOOR :- FLUSH DOOR WITH STEEL FRAME, P.V.C. DOOR SHUTTER
WITH STEEL FRAME.
WINDOW :- ALUMINIUM SLIDING GLAZING WITH FRONT M.S. GRILL
GENERAL SPECIFICATION FOR FIRST FLOOR
(TOTAL AREA = 1345.62 SQM)θΦǿ
S.NO
|
BEAM)
|
BEAM
B X D (MM)
|
REINFORCEMENT
CONTINUOUS BARS
|
REINFORCEMENT
EXTRA BARS
|
STIRRUPS ALL TWO LEGGED
|
|||
TOP BOTTOM
|
TOP BOTTOM
|
L/4 OF SPAN BALANCE OF
SPAN
|
||||||
1
|
PB1
|
200x300
|
2-12
ǿ
|
2-12
ǿ
|
-
|
-
|
8MM@150
c/c
|
8MM@200
c/c
|
2
|
PB2
|
200x300
|
2-12
ǿ
|
2-12
ǿ
|
1-12
ǿ
|
1-12
ǿ
|
8MM@150
c/c
|
8MM@200
c/c
|
3
|
PB3
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
-
|
-
|
8MM@120
c/c
|
8MM@170
c/c
|
4
|
PB4
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
1-12
ǿ
|
1-12
ǿ
|
8MM@120
c/c
|
8MM@170
c/c
|
5
|
PB5
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
2-12
ǿ
|
2-12
ǿ
|
8MM@120
c/c
|
8MM@170
c/c
|
6
|
PB6
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
3-12
ǿ
|
2-12
ǿ
|
8MM@120
c/c
|
8MM@170
c/c
|
7
|
PB7
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
-
|
-
|
8MM@120
c/c
|
8MM@170
c/c
|
8
|
PB8
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
1-12
ǿ
|
1-12
ǿ
|
8MM@120
c/c
|
8MM@170
c/c
|
9
|
PB9
|
200x400
|
2-12
ǿ
|
2-12
ǿ
|
2-12
ǿ
|
2-12
ǿ
|
8MM@120
c/c
|
8MM@170
c/c
|
FOOTING SCHEDULE
S.NO.
|
DESIGNATION
|
SIZE OF THE FOOTING
(MM)
|
DEPTH OF THE
FOOTING (MM)
|
REINFORECEMENT
|
CONCRETE GRADE
|
1
|
F1
|
2400X2200
|
550
|
12 DIA @ 150MM C/C
|
M-20
|
2
|
F2
|
2100X2000
|
450
|
12 DIA @ 175MM C/C
|
M-20
|
3
|
F3
|
1900X1700
|
400
|
12 DIA @ 200MM C/C
|
M-20
|
4
|
F4
|
1700X1500
|
400
|
10 DIA @ 150MM C/C
|
M-20
|
5
|
F5
|
1000X1000
|
300
|
10 DIA @ 200MM C/C
|
M-20
|
6
|
F6
|
600X600
|
200
|
10 DIA @ 200MM C/C
|
M-20
|
COLUMN SCHEDULE
S.NO
|
COLUMN NO.
|
COLUMN SIZE
|
MAIN REINFORECEMENT
|
SPACING
|
1
|
C1
|
300X500
|
14-20 ǿ
|
8MM@200MM C/C
|
2
|
C2
|
300X500
|
12-20 ǿ
|
8MM@200MM C/C
|
3
|
C3
|
300X500
|
10-20 ǿ
|
8MM@200MM C/C
|
4
|
C4
|
300X400
|
12-16 ǿ
|
8MM@200MM C/C
|
5
|
C5
|
300X400
|
10-16 ǿ
|
8MM@200MM C/C
|
6
|
C6
|
300X400
|
8-16 ǿ
|
8MM@200MM C/C
|
7
|
C7
|
300X300
|
4-20 ǿ & 4-16 ǿ
|
8MM@200MM C/C
|
8
|
C8
|
200X400
|
4-16 ǿ & 4-12 ǿ
|
8MM@200MM C/C
|
9
|
C9
|
200X400
|
8-12 ǿ
|
8MM@200MM C/C
|
10
|
C10
|
200X200
|
4-12 ǿ
|
8MM@200MM C/C
|
NOTE-
1. COVER TO REINFORCEMENT
SHALL BE AS :-
COLUMN - 40 MM
FOOTING - 50MM
SLAB - 20MM
BEAM - 30MM
2. LAP LENGTH IN REINFORCEMENT
BAR SHALL BE CLAUSE 25.2.5.1OF IS
456:2000
3. SOILBEARING CAPACITY HAS
BE WRITTEN AS 15 TON AT A DEPTH OF 1.65 M AS PER INFORMATION PROVIDED.
4. BUILDING HAS BE DESIGNED
FOR SESMIC ZONE AS PER IS 1983 PART II-2002
5. DEVELOPMENT LENGTH
MIX IN TENSION IN
COMPRESSION
M-20 30 MM ǿ 24MM ǿ
MESH FOR COLUMNS
GENERAL
SPECIFICATION
1. COVER
TO REINFORCEMENT SHALL BE AS :-
COLUMN - 40 MM
FOOTING - 50MM
SLAB - 20MM
BEAM - 30MM
2. ANCHORAGE
LENGTH IN REINFORCEMENT BAR SHALL BE
CLAUSE 25.2.5.1 OF IS 456:2000
3. SOILBEARING
CAPACITY HAS BE WRITTEN AS 15 TON AT A DEPTH OF 1.65 M AS PER DESIGNED FOR
SESMIC ZONE AS PER IS 1983 PART II-2002 AND WIND CODE 1997.
IN THIS SITE WE FOUND TYPES OF SOIL SOTHAT WE COULD FOUND SBC OF THIS SOIL. WE OBSERVED
THAT HERE TWO TYPES OF FOOTINGS ARE USED -
1. COMBINED
FOOTING
2. SPREAD
FOOTING.
(1)
COMBINED FOOTING :- A
SPREAD FOOTING WHICH SUPPRTS TWO OR MORE COLUMNS IS TERMED AS A COMBINED
FOOTING. SUCH A FOOTING IS PROVIDED WHEN THE INDIVIDUAL FOOTINGS ARE EITHER
VERY NEAR TO EACH OTHER OR OVERLAP. COMBINED FOOTING MAY EITHER BE RECTANGULAR
OR TRAPEZOIDAL.
(2)
SPREAD FOOTING :- A SPREAD FOOTING OR
SIMPLY FOOTING IS A TYPE OF SHALLOW FOUNDATION USED TO TRANSMIT THE LOAD OF AN
ISOLATED COLUMN OR THAT OF A WALL, ON THE SUBSOIL.
SQUARE COLUMN FOOTING
COLUMN (AS PER IS 456:2000)
INTRODUCTION :- A COLUMN OR STRUT IS A COMPRESSION MEMBER. WHEN A MEMBER
CARRYING MAINLY AXIAL LOAD IS VERTICAL, IT IS A TERMED AS ‘COLUMN’ WHILE IF IT IS A INCLINED COLUMN, IT IS TERMED AS A
‘STRUT’.
SLENDERNESS RATIO :- IT IS A THE RATIO OF EFFECTIVE LENGTH
OF THE COLUMN TO LEAST LATERAL DIMENSION.
S.R. = Lef/ b
|
TYPES OF COLUMNS :-
Lef/ b < 12
|
(a)
SHORT
COLUMN :- THE
COLUMN IS CONSIDERED AS SHORT WHEN THE SLENDERNESS RATIO OF COLUMN IS LESS THAN
OR EQUAL TO 12.
(b)
LONG
COLUMN :-
THE COLUMN IS CONSIDERED AS SHORT WHEN THE
SLENDERNESS RATIO OF COLUMN IS LESS THAN OR EQUAL TO 12.
Lef/ b > 12
|
EFFECTIVE LENGTH OF THE COLUMN
(AS PER IS 456:2000)
INTRODUCTION
:- THE EFFECTIVE LENGTH OF A COLUMN IS DEFINED AS THE
COLUMN WHICH TAKES PART IN BUCKLIN UNDER THE ACTION OF THE LOADS. THIS IS ALSO
DEFINED AS THE LENGTH BETWEEN THE POINT OF CONTRAFLEXURE OF THE BUCKLED COLUMN.
THE
UNSUPPORTED LENGTH OF THE COLUMN IS THE CLEAR LENGTH OR HEIGHT BETWEEN THE
FLOOR AND THE LOWER LEVEL OF THE CEILING .
S.NO
|
DIFFERENT END CONDITIONS OF THE COLUMN
|
THEORETICAL VALUE OF EFFECTIVE LENGTH
|
RECOMMENDED
VALUE OF EFFECTIVE LENGTH
|
1.
|
BOTH ENDS ARE
FIXED
|
0.5L
|
0.65L
|
2.
|
BOTH ENDS ARE HINGED
|
1.0L
|
1.0L
|
3.
|
FIXED AT ONE
END & HINGED AT OTHER END
|
0.7L
|
0.8L
|
4.
|
FIXED AT ONE
END & FREE AT OTHER END
|
2.0L
|
2.0L
|
BEAM (AS PER IS
456:2000)
INTRODUCTION :- THOUGH
PLAIN CEMENT CONCRETE HAS HIGH COMPRESSIVE STRENGTH , IT’S TENSILE STRENGTH IS RELATIVELY
LOW, THE TENSILE STRENGTH OF CONCRETE IS ABOUT 10% TO 15% OF IT’S COMPRESSIVE
STRENGTH.
HENCE,
IF A BEAM IS MADE OF PLAIN CEMENT CONCRETE, IT HAS A VERY LOW LOAD CARRYING
CAPACITY SINCE IT’S LOW TENSILE STRENGTH LIMITS ITS OVEERALL STRENGTH. IT IS
THEREFORE REINFORCED BY PLACING STEEL BARS IN THE TENSILE ZONE OF THE CONCRETE
BEAM SOTHAT THE COMPRESSIVE BENDING STRESS IS CARRIED BY CONCRETE AND TENSILE
BENDING STRESS IS CARRIED ENTIRELY BY STEEL REINFORCING BARS.
THE
JOINT ACTION OF STEEL AND CONCRETE IN A REINFORCED CONCRETE SECTION IS
DEPENDENT OF THE FOLLOWING FACTORS-
(I) BOND BETWEEN CONCRETE AND
STEEL BARS.
(2) ABSENCE OF CORROSION OF
STEEL BARS EMBEDDED IN THE CONCRETE.
(3) THERMAL EXPANSION OF BOTH
CONCRETE AND STEEL.
TYPES
OF BEAMS (AS PER IS 456:2000)
(1) SINGLY REINFORCED BEAM :- SINGLY REINFORCED SECTION THE REINFORCEMENT IS
PROVIDED TO CARE TENSION IN THE BOTTOM OF THE BEAM. IT IS CLASSIFIED INTO THE
FOLLOWING CATEGORIES-
(a) BALANCED SECTION :- WHEN THE
MOMENT OF RESISTANCE OF THE SECTION IS EQUAL TO THE THE BENDING MOMENT THAN IT
IS A BALANCED SECTION.
(b) UNDER REINFORCED
SECTION :- WHEN THE MOMENT OF RESISTANCE OF
THE SECTION IS LESS THEN THE BENDING MOMENT THAN IT IS A UNDER REINFORCED
SECTION.
(C) OVER REINFORCED SECTION :- WHEN THE MOMENT
OF RESISTANCE OF THE SECTION IS MORE THEN THE BENDING MOMENT THAN IT IS A UNDER
REINFORCED SECTION.
(2) DOUBLY REINFORCED BEAM :- DOUBLY REINFORCED SECTION IS TO BE DESIGNED TO
RESTRICT THE DEPTH OF BEAM IN CASE OF HEAD ROOM CONDITION OR IF THE BENDING
MOMENT IS MORE THAN 25% OF MOMENT OF RESISTANCE OF THE SECTION THAN DOUBLY
REINFORCED SECTION IS TO BE DESIGNED. IN DOUBLY REINFORCED BEAM REINFORCEMENT
IS TO BE PROVIDED BOTH IN COMPRESSION AND TENSION ZONES.
(a)
CANTILEVER BEAM
(b)
CONTINUOUS BEAM
(c)
DEEP BEAM
COMBINED
FOOTING
FOOTING
INTRODUCTION
:- FOOTING IS THAT PORTION OF THE FOUNDATION WHICH
ULTIMETELY DELIVERS THE LOAD OF THE SOIL AND IS THUS IN CONTACT WITH IT.
TYPES
OF FOOTINGS :-
(1)
SPREAD
FOOTING :- A
SPREAD FOOTING OR SIMPLY FOOTING IS A TYPE OF SHALLOW FOUNDATION USED TO
TRANSMIT THE LOAD OF AN ISOLATED COLUMN OR THAT OF A WALL, ON THE SUBSOIL.
(2)
COMBINED
FOOTING :- A
SPREAD FOOTING WHICH SUPPRTS TWO OR MORE COLUMNS IS TERMED AS A COMBINED
FOOTING. SUCH A FOOTING IS PROVIDED WHEN THE INDIVIDUAL FOOTINGS ARE EITHER
VERY NEAR TO EACH OTHER OR OVERLAP. COMBINED FOOTING MAY EITHER BE RECTANGULAR
OR TRAPEZOIDAL.
(3)
STRAP
OR CANTILEVER FOOTING :- A
STRAP FOOTING CONSIST OF SPREAD FOOTING OF TWO COLUMNS CONNECTED BY A STRAP
BEAM. THE STRAP BEAM DOES NOT REMAIN IN CONTACT WITH SOIL AND THUS DOES NOT
TRANSFER ANY PRESSURE TO THE SOIL.
FOUNDATION
INTRODUCTION
:- FOUNDATION IS THE STRUCTURE BELOW PLINTH LEVEL OR
BETWEEN SUB-SOIL & PLINTH LEVEL. THE FOUNDATION IS TO DISTRIBUTE LOADS
COMINGS OVER IT TO THE SUB-SOIL.IT SHOULD ON A STABLE GROUND. IT DISTRIBUTE
LOADS AT A SUFFICIENT AREA AND AVOIDS THE UNEQUAL SETTLEMENT OF THE FOUNDATION.
TYPES OF FOUNDATION
(1)
SPREAD
FOOTING FOUNDATION :- THIS TYPE OF FOUNDATION IS THE SIMPLEST AND
COMMONLY USED IN ORDINARY TYPE OF BUILDINGS, THE BASE AREA OF THE FOUNDATION IS
WIDENED.
(2)
GRILLAGEFOUNDATION
:- THIS TYPE OF FOUNDATION CONSIST OF STEEL OR WOODEN JOIST ARRANGED IN STEPPED
MANNER. A TRENCH 90 CM TO 150 CM DEE, IS EXCAVATED AND LEVELLED. THEN A LAYER
OF 23 CM TO 30 CM OF C.C., 1:2:4 IS SPREAD AND COMPACTED. OVER THIS CONCRETE
STEEL I-BEAMS ARE LAID AND ARE PLACED AT SUITABLE INTERVAL OF 45CM TO 90 CM.
THE LENGTH OF I-BEAMS EQUAL TO THE WIDTH OF THE FOUNDATION.
(3)
PILE
FOUNDATION
:- PILE IS AN ELEMENT OF CONSTRUCTION
PLACED IN THE GROUND EITHER VERTICALLY OR SLIGHTLY INCLINED TO INCREASE THE
LOAD CARRYING CAPACITY OF THE SOIL.IT IS USED WHEN SOIL IS VERY SOFT OR
GRILLAGE FOUNDATION IS EXPENSIVE OR BUILDING IS VERY HEAVY OR THE BUILDING IS
TO BE CONSTRUCTED AT A SEA-SHORE OR RIVER BED.
(4)
RAFT
OR MAT FOUNDATION
:- IT IS THE CONTINUOUS SLAB COVERING THE
WHOLE AREA LIKE A MAT OR RAFT. IT IS USED IN DAMP SOIL HAVING LOW BEARING
CAPACITY OF THE SOIL. IT PREVENT THE BUILDING FROM UNEQUAL SETTLEMENT OR
SINKING.
(5)
WELL FOUNDATION
:- THIS TYPE OF FOUNDATION IS USUALLY ADOPTED IN THE CONATRUCTION OF BRIDGES
AND LONG SPAN CULVERTS OR IN SANDY SOIL IN WATER.
(6)
STEPPED
OR BENCHED FOUNDATION
:- IN THIS METHOD THE FOUNDATION IS PROVIDED IN FORM OF STEP OF
CONCRETE. THE HEIGHT OF EACH STEP IS KEPT UNIFORM.
SLAB
CASTING
SLAB (AS PER IS 456:2000)
INTRODUCION :- IN
REINFORCED CONCRETE CONSTRUCTION, THE SLAB IS USED STRUCTURAL ELEMENT FORMING
FLOORS AND ROOMS OF THE BUILDING.
A CONCRETE IS THE
PLAIN ELEMENT HAVIMG THE DEPTH D MUCH SMALLER THAN IT’S SPAN AND WIDTH. IT MAY
BE SUPPORTED BY REINFORCED CONCRETE BEAMS, BY MASONARY WALLS OR COLUMNS. IT
CARRIES UDL AND TRANSFER IT TO THE STRUCTURAL ELEMENT.
TYPES OF SLAB :-
Ly / Lx > 2
|
(I) ONE-WAY SLAB
Ly / Lx < 2
|
(II) TWO-WAY SLAB
NOTE:- (Ly = LONGER SPAN)
(Lx = SHORTER SPAN)
(III) FLAT SLAB
(IV) CIRCULAR AND NON-RECTANGULAR
SLAB
(V) GRID OR WAFFLE SLAB
STAIRCASE
INTRODUCTION:- A STAIRCASE CONSISTS OF A NUMBER OF
STEPS ARRANGED IN A SERIES, WITH LANDING AT APPROPRIATE LOCATION FOR THE
PURPOSE OF GIVING ACCESS TO DIFFERENT FLOORS OF A BUILDING. THE WIDTH OF A
STAIRCASE GENERALLY KEPT 1M FOR RESIDENTIAL & 2M FOR PUBLIC BUILDINGS.
TYPES OF STAIRS :-
(1) STRAIGHT STAIR :- A STRAIGHT FLIGHT IS ONE IN WHICH ALL STEPS ARE
PARALLEL TO ONE AND ANOTHER AND RISES IN THE SAME DIRECTION.
(2) DOG-LEGGED STAIR :- A DOG
LEGGED SAIR IS CALLED FROM ITS BEING BENT OR CROOKED SUDDENLY ROUND IN FANCIED
RESEMBLANCE TO DOG’S LEG.
(3) OPEN WELL STAIR :- AN OPEN WELL STAIR GIVES SATISFACTORY RESULTS AND
HENCE IT SHOULD BE TRIED TO PROVIDE AN OPEN WELL STAIR IT REQUIRES A LITTLE
MORE SPACE THEN A DOG LEGGED STAIR.
(4) GEOMETRICAL STAIRS
:- SUCH A STAIR REQUIRES LITTLE MORE WIDTH, BUT ONLY ABOUT THE SAME LENGTH
OF A SPACE AS A DOG LEGGED STAIR.
(5) CIRCULAR STAIRS :-
CIRCULAR STAIRS ARE GENERALLY PROVIDED AT THE BACK SIDE OF THE BUILDING FOR
RENDERING ACCESS TO IT’S VARIOUS FLOORS FOR SERVICE PURPOSE. THIS TYPE OF STAIR
MOSTLY CONSTRUCTED IN R.C.C. AND IRON.
(6) BIFURCATED STAIR :-
THIS TYPE OF STAIR IS VERY COMMON IN PUBLIC BUILDING IN IT THE BOTTOM WIDE
FLIGHT IS DIVIDED AT A LANDING INTO TWO NARROWER FLIGHTS WHICH BRANCH OFF TO
THE RIGHT AND LEFT.
NOTE :-
(THE MAX NO. OF STEPS IN ONE FLIGHT
SHOULD NOT BE MORE THAN 12)
TERMS USED IN STAIR CASE
(1) TREAD :- IT IS THE HORIZONTAL MEMBER WHICH FORMS THE UPPER
SURFACE OF A STEP.
(2) RISER :-
IT IS THE FRONT VERTICAL PORTION OF A
STEP TO WHICH THE TREAD IS CONNECTED.
(3) PITCH :- IT IS THE
ANGLE BETWEEN THE PITCH LINE AND THE
HORIZONTAL.
(4) NOSING :- IT IS THE
PROJECTED EDGE OF A TREAD USUALLY MOULDED.
(5) FLIGHT :- A CONTINUOUS SERIES OF STEPS EXTENDING FROM FLOOR
TO FLOOR, OR FLOOR TO LANDING, OR LANDING TO LANDING, IS KNOWN AS FLIGHT.
(6) GOING :- GOING OR
RUN OF THE STEP IS THE HORIZONTAL DISTANCE BETWEEN THE FACES OF THE CONSECUTIVE
RISERS.
(7) BALUSTERS :- THE VERTICAL MEMBER WHICH SUPPORTS THE HANDRAIL
AND PROTECT TO OPEN SIDE.
(8) HANDRAIL :- IT IS MOULDED MEMBER RUNNING PARALLEL TO THE
NOSING LINE OR LANDNG.
(9) SPRINGER :- IT IS THE INCLINED MEMBER LAID PARALLEL TO THE
NOSING LINE OR LANDING.
(10) PITCH LINE :- THE LINE JOINING THE INTERSECTION OF THE FACE OF
EACH RISERS AND THE TOP OF EACH TREAD IS CALLED THE PITCH LINE.
DESIGN
CRITERIA FOR BEAMS & SLABS
(AS
PER IS 456 : 2000)
(1) EFFECTIVE SPAN :-
(a) SIMPLY SUPPORTED BEAM OR SLAB :- THE EFFECTIVE SPAN OF A MEMBER THAT IS NOT BUILT INTEGRALLY WITH IT’S
SUPPORTS SHALL BE TAKEN AS CLEAR SPAN PLUS THE EFFECTIVE DEPTH OF BEAM OR SLAB
OR CENTRE TO CENTRE OF SUPPORTS, WHICHEVER IS LESS.
(b) CONTINUOUS BEAM OR SLAB :- IN THIA CASE, IF THE WIDTH OF THE SUPORT IS LESS THEN
1/12 OF THE CLEAR SPAN, THE EFFECTIVE SPAN SHALL BE AS IN (a). IF THE SUPPORTS
ARE WIDER THEN 1/12 OF THE CLEAR SPAN OR 600 MM WHICHEVER IS LESS.
(C) CANTILEVER :- THE EFFECTIVE LENGTH OF CANTILEVER SHALL BE TAKEN SD IT’S
LENGTH TO THE FACE OF THE SUPPORT PLUS HALF THE EFFECTIVE DEPTH.
(2) CONTROL OF DEFLECTION :- BASICVALUES OF SPAN TO DEPTH RATIOS FOR SPAN UPTO 10M
CANTILEVER 7
SIMPLY
SUPPORTED 20
CONTINUOUS 26
(3) SLENDERNESS RATIO :- S.R
IS TAKEN 60b OR 250b^2/d WHICHEVER IS LESS FOR SIMPLY & CONTINUOUS SLAB.
BUT FOR CANTILEVER THE CLEAR DISTANCE FROM THE FREE END OF THE CANTILEVER TO
THE LATERAL RESTRAINT SHALL NOT BE EXCEED 25b OR 100b^2/d WHICHEVER IS LESS.
(4)
SHEAR REINFORCEMENT :- SHEAR REINFORCEMENT IS PROVIDED IN FOLLOWING OF THE FORM.
(A) VERTICAL
STIRRUPS
(B) BENT
UP BARS ALONG WITH STIRRUPS
(C)INCLINED
STIRRUPS
(5) MAX SPACING OF SHEAR REINFORCEMENT :-
THE MAX. SPACING OF
SHEAR REINFORCEMENT SHALL NOT EXCEED 0.75d FOR VERTICAL STIRRUPS (WHERE d =
EFFECTIVE DEPTH OF THE SECTION)
CONCLUSION
We can conclude that there is difference
between the theoretical and practical work done. As the scope of understanding
will be much more when practical work is done. As we get more knowledge in such
a situation where we have great experience doing the practical work. Knowing
the loads we have designed the slabs depending upon the ratio of longer to
shorter span of panel. In this project we have designed slabs as two way slabs
depending upon the end condition, corresponding bending moment. The
coefficients have been calculated as per I.S. code methods for corresponding
lx/ly ratio. The calculations have been done for loads on beams and columns and
designed frame analysis by moment distribution method. Here we have a very low
bearing capacity, hard soil and isolated footing done.
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