Abstract: This
report includes the concrete design of beams and columns of a two storey
building. The whole procedure of analysis & designing is done in Staad.Pro.
The process of designing is defined in the best suitable manner it can be. All
the specific results are also shown in the end.
Introduction to
Staad.pro V8i
Stadd.Pro V8i is the most
popular structural engineering software product for 3D model generation,
analysis and multi-material design. It has an intuitive, user-friendly GUI,
visualization tools, powerful analysis and design facilities and seamless integration
to several other modeling and design software products. The software is fully
compatible with all Windows operating systems but is optimized for Windows XP.
For
static or dynamic analysis of bridges, containment structures, embedded
structures (tunnels and culverts), pipe racks, steel, concrete, aluminum or
timber buildings, transmission towers, stadiums or any other simple or complex
structure, Stadd.Pro has been the choice of design professionals around the
world for their specific analysis needs.
Stadd.Pro is a general purpose
program for performing the analysis and design of a wide variety of types of
structures. The basic three activities which are to be carried out to achieve
that goal - a) model generation b) the calculations to obtain the analytical
results c) result verification - are all facilitated by tools contained in the
program's graphical environment.
The
staad model is prepared to the scale in the working space of staad. The frame
structure model is generated which consists of beams and columns and then the
material with their cross-section properties are inputted to staad. The loads
are then assigned and after that the structure is analyzed with the help of the
staad program.
The whole
process of the analysis and design are given below.
1. Inputting the job Information: Firstly
the information of the project is written after opening the staad. As the name
of the project/job, Client’s name and the date when project started and the
name of the Engineer as well and much more information is inputted.
2. Generating the 3d model geometry: There
are two methods of creating a structure data in staad.
a. Using the command file also called “The staad
editor method”.
b. Using the graphical user interface (GUI).
We
have done our whole of the programming with the help of GUI method because it
is easier and much advance tool of staad.
The
model of the framed structure is generated in staad by Snap Node/Beam dialog
box which appears when we select the grid from the top menu bar. Then the nodes
and beams are created by this command at the suitable distances as per our
need.
Fig. The model of structure
with all the beams and nodes.
3. Assigning the material: As after
creating the beams and columns we will assign material to them as we require.
Our design is concrete design hence we have assigned the concrete material to
the beams and columns.
4. Specifying member properties: The
properties of the beams and columns is their size(width, depth of
cross-section).So with the help of this command we have inputted the different
properties (as circular, rectangular, square) and assign these properties to
specified members.
Fig. 3d Rendered model after
specifying the properties to member.
5. Specifying material constants: As
we assigned the concrete material so by default we have the constants of
concrete and we don’t need to use this command separately. Or if we need to
change the constants we can do so by this command.
6. Specifying member offset: As default
in the staad design of model and after assigning properties, the staad takes
the beams and columns center to center and if we want to have beams end to end
over the columns then we use Beam offset
command.
Fig. Beam before offsetting
Fig. Beam after offsetting
7. Printing member information: As
if we would like to get a report consisting of information about all the
members including start and end joint numbers, members length in staad output
file then we use this command as by going to
Commands Pre-Analysis Print Member
information from top menu bar.
8. Specifying Supports: The supports
are first created (as we created fixed supports) and then these are assigned to
all the lowermost nodes of structure where we are going to design the
foundation.
Fig. The model with the fixed
supports.
9. Specifying Loads: This is done in
following two steps :
a. Firstly creating all the load cases.
b. Then assigning them to respective members and
nodes.
The staad
program can produce all types of loads and can assign them to the structure. It
also has the capability to apply the dead load on the structure. There are some
definitions of loads which are firstly created according to IS codes before
creating specific load cases (As Seismic or wind load). Here below are some
types of loads as we have assigned.
a. Dead Load: The load coming on
framed structure due to self weight of beams, columns, slabs or walls. This
load will act as uniformly distributed load over the supporting beams.
|
3.05 KN/m
|
Fig. The dead load coming on
beam no. 31 having UDL of -3.05 KN/m.
b. Live Load: The live load comes on
structure due to extra necessary things in the house. There will be different
Live Loads acting in the structure due to different uses of building. As here
we have used various types of different live loads in our structure.
i. The
Floor load coming on the beams form the trapezoidal load on one longer beam of
floor area.
Fig. Trapezoidal load coming on
beam due to floor load.
ii. The Floor load coming on the beams form the triangular load on one
shorter beam of floor area.
Fig. Triangular Load coming on beam
due to floor load.
iii. There
will be some moments coming on beam these can also be applied on beams. As in
our structure the moments are coming due to the cantilever slab due to balcony
on back side of house on the ground floor and top floor.
|
33.75 KN-m/m
Acting in GX Dir.
|
Fig. The moment coming on beam of
top floor due to balcony.
c. Wind Load: The Wind load
coming on structure is defined firstly by load definitions. Then inputting the
required data. And after that the load is created to apply in suitable
direction.
|
Wind Load
designed for wind velocity of 39m/s
|
Fig. The wind load acting on back
wall of house.
d. Load Combinations: The load
combinations have been created with the command of auto load combinations. By
selecting the Indian code we can generate loads according to that and then
adding these loads. These combinations do not required to be assigned on
members.
Hence all the
loads are assigned on the structure we will move towards forward step.
10.Specifying
the analysis type: Before doing the analysis for the loads we require
specifying analysis command which we need is linear static type. Choosing
statics check, we will add this command.
11.Post-Analysis
print command: As we require obtaining member end forces and support
reactions written in the output file. By clicking on post-analysis a dialog box
will open then by clicking define command, we can add the commands
which we need and can assign them to members for which these will be analyzed.
12.Run
Analysis: The structure will be analyzed to the loads and this command
will also show if there is any warning or error.
13.Post-Processing
mode: We can see results in this mode. The deflection, bending moment,
shear forces and reactions on supports can been on the structure with values.
The figures shown below are under Dead Load. We can also see figures under Live
Load or other which we want.
Fig. The bending moments on each
beam and column.
Fig. The Displacement on each beam
and column.
Fig. The shear force in
Y-Direction.
Fig. The Stresses on each beam and
column.
After doing all
the structural analysis of our structure, we have designed it to find out the
steel used for the reinforcement for the columns and beams.
By selecting the
code IS: 456 2000 for the concrete design we will then define parameters for
our design as:
1. Clear: Providing clear cover to
beams and columns as inputted .04m in our case.
2. FC: This is the Compressive
strength of concrete as 25000 KN/m2.
3. FY Main: This is the yield
strength of the main reinforcement steel as 415000 KN/m2.
4.FY SEC: The yield strength of
secondary reinforcement steel as 415000KN/m2.
5. MAXMAIN: The maximum bar size to
be provided for main reinforcement as 25mm.
6. MAXSEC: The maximum bar size to
be provided for secondary reinforcement as 25mm.
7. METHOD: To consider minimum
eccentricity about one axis at a time this command is selected.
8. MINMAIN: The minimum bar size to
be provided for main reinforcement as 10mm.
9. MINSEC: The minimum bar size to
be provided for secondary reinforcement as 8mm.
10.MMAG: The
factor by which the column design moments will be magnified as 1.5 is taken in
our project.
11.REINF: This
command is used for selecting the tied or spiral columns we have used tied
columns.
12.TORSION: This
will be selected if we want to have design for torsion.
13.TRACK: The
track parameter is selected as per need it gives three different options.
After giving all
these inputs we will now give commands as for the design of beams and columns.
These are selected once added and then assigned to the structure to appropriate
components.
Then the
structure is again analyzed for the generation of report.
The Final Report
that we have generated actually of our staad project is consisting of 550 pages
(as generated for all beams and columns) and hence here we have given some
specific results of that report as shown in figure below the different beams
with Beam No’s:
FIG. The Structure showing
different beams and columns with their no’s.
BEAM NO.29 DESIGN RESULTS
M30 Fe415
(Main) Fe415
(Sec.)
LENGTH: 3840.0 mm SIZE: 300.0
mm X 300.0 mm COVER: 25.0 mm SUMMARY OF REINF.
AREA (Sq.mm)
SECTION 0.0
mm 960.0
mm 1920.0 mm 2880.0
mm 3840.0 mm
TOP 530.92 193.78 0.00 165.90 436.72
REINF. (Sq.
mm) (Sq.
mm) (Sq.
mm) (Sq.
mm) (Sq. mm)
BOTTOM 293.47 266.71 165.90 1
65.90 165.90
REINF. (Sq.
mm) (Sq.
mm) (Sq.
mm) (Sq.
mm) (Sq. mm)
SUMMARY
OF PROVIDED REINF. AREA
SECTION 0.0
mm 960.0
mm 1920.0 mm 2880.0
mm 3840.0 mm
TOP 7-10Ã 3-10Ã 2-10Ã 3-10Ã 6-10Ã
REINF. 1
layer(s) 1 layer(s) 1
layer(s) 1
layer(s) 1 layer(s)
BOTTOM 4-10Ã 4-10Ã 3-10Ã 3-10Ã 3-10Ã
REINF. 1
layer(s) 1 layer(s) 1
layer(s) 1
layer(s) 1 layer(s)
SHEAR REINF. 2 legged 10Ã @ 120 mm c/c.
SHEAR DESIGN
RESULTS AT DISTANCE d (EFFECTIVE DEPTH) FROM FACE OF THE SUPPORT:
SHEAR DESIGN
RESULTS AT 415.0 mm AWAY FROM START SUPPORT
VY
= 14.27 MX = 25.80 LD = 2
Provide
2 Legged 10Ã @ 120 mm c/c
SHEAR DESIGN
RESULTS AT 465.0 mm AWAY FROM END SUPPORT
VY
= -18.48 MX = 25.11 LD = 2
Provide
2 Legged 10Ã @ 120 mm c/c
COLUMN NO.1 DESIGN RESULTS
M30 Fe415
(Main) Fe415
(Sec.)
LENGTH: 3000.0 mm CROSS
SECTION: 300.0 mm X 300.0 mm COVER: 40.0 mm
** GUIDING LOAD CASE: 3 END JOINT: 2 TENSION COLUMN
REQD. STEEL
AREA : 720.00 Sq.mm.
REQD. CONCRETE
AREA: 89280.00 Sq.mm.
MAIN REINFORCEMENT
: Provide 4 - 16 dia. (0.89%, 804.25
Sq.mm.)
(Equally
distributed)
TIE
REINFORCEMENT: Provide 8 mm dia. rectangular ties @ 255 mm c/c.
SECTION CAPACITY
BASED ON REINFORCEMENT REQUIRED (KN-M)
Puz: 1429.38 Muz1: 30.97 Muy1 :
30.97
INTERACTION RATIO: 0.00 (as per Cl. 39.6, IS456:2000)
SECTION CAPACITY
BASED ON REINFORCEMENT PROVIDED (KN-M)
WORST
LOAD CASE: 3
END JOINT: 37
Puz : 1454.46 Muz : 33.58 Muy :
33.58 IR: 0.01
COLUMN N O. 2 DESIGN RESULTS
M30 Fe415
(Main) Fe415
(Sec.)
LENGTH: 3000.0 mm CROSS
SECTION: 210.0 mm X 400.0 mm COVER:
40.0 mm
** GUIDING LOAD CASE: 2 END JOINT: 2 TENSION
COLUMN
REQD. STEEL
AREA : 692.52 Sq.mm.
REQD. CONCRETE
AREA: 83307.48 Sq.mm.
MAIN
REINFORCEMENT: Provide 8 - 12 dia.
(1.08%, 904.78 Sq.mm.)
(Equally
distributed)
TIE
REINFORCEMENT: Provide 8 mm dia. rectangular ties @ 190 mm c/c
SECTION CAPACITY
BASED ON REINFORCEMENT REQUIRED (KN-M)
Puz : 1340.20 Muz1 :
49.46 Muy1 : 23.50
INTERACTION RATIO: 0.99 (as per Cl. 39.6, IS456:2000)
SECTION CAPACITY
BASED ON REINFORCEMENT PROVIDED (KN-M)
WORST LOAD CASE:
3
END JOINT: 38
Puz : 1403.40 Muz : 52.40 Muy :
24.34 IR: 0.01
COLUMN N O. 10 DESIGN RESULTS
M30 Fe415
(Main) Fe415
(Sec.)
LENGTH: 3000.0 mm CROSS
SECTION: 400.0 mm X 210.0 mm COVER:
40.0 mm
** GUIDING LOAD CASE: 2 END JOINT: 25 TENSION
COLUMN
REQD. STEEL
AREA : 672.00 Sq.mm.
REQD. CONCRETE
AREA: 83328.00 Sq.mm.
MAIN
REINFORCEMENT: Provide 8 - 12 dia.
(1.08%, 904.78 Sq.mm.)
(Equally
distributed)
TIE
REINFORCEMENT: Provide 8 mm dia. rectangular ties @ 190 mm c/c
SECTION CAPACITY
BASED ON REINFORCEMENT REQUIRED (KN-M)
Puz : 1334.09 Muz1 :
19.46 Muy1 : 40.19
INTERACTION RATIO: 0.12 (as per Cl. 39.6, IS456:2000)
SECTION CAPACITY
BASED ON REINFORCEMENT PROVIDED (KN-M)
WORST LOAD CASE:
2
END
JOINT: 25 Puz : 1403.40 Muz
: 24.51 Muy : 52.82 IR: 0.09
COLUMN N O. 62 DESIGN RESULTS
M30 Fe415
(Main) Fe415
(Sec.)
LENGTH: 6000.0 mm CROSS SECTION: 424.3
mm dia. COVER:40mm
** GUIDING LOAD
CASE: 3 END JOINT: 32 TENSION
COLUMN
REQD. STEEL
AREA : 1130.97 Sq.mm.
REQD. CONCRETE
AREA: 140240.66 Sq.mm.
MAIN
REINFORCEMENT: Provide 6 - 16 dia.
(0.85%, 1206.37 Sq.mm.)
(Equally distributed)
TIE
REINFORCEMENT: Provide 8 mm dia. circular ties @ 255 mm c/c
SECTION CAPACITY
BASED ON REINFORCEMENT REQUIRED (KN-M)
Puz : 2245.26 Muz1 : 63.22 Muy1 : 63.22
INTERACTION RATIO: 0.01 (as per Cl. 39.6, IS456:2000)
SECTION CAPACITY
BASED ON REINFORCEMENT PROVIDED (KN-M)
WORST LOAD
CASE: 3
END
JOINT:66 Puz : 2267.71 Muz :
65.58 Muy : 66.32 IR: 0.02
COLUMN NO. 261 DESIGN RESULTS
M25 Fe415
(Main) Fe415
(Sec.)
LENGTH: 3000.2 mm CROSS SECTION: 424.3
mm dia. COVER: 40 mm
** GUIDING LOAD
CASE: 2 END JOINT: 65 TENSION COLUMN
DESIGN AT JOINT
NO. 65
CASE 1: MINIMUM
ECC. ABOUT Y CONSIDERED
DESIGN FORCES
(KN-M)
DESIGN AXIAL
FORCE (Pu): 29.8
About
Z About Y
INITIAL
MOMENTS : 7.6 13.8
MOMENTS
DUE TO MINIMUM
ECC. : 0.00 0.60
SLENDERNESS
RATIOS : - -
MOMENTS
DUE TO SLENDERNESS
EFFECT: - -
MOMENT
REDUCTION
FACTORS : - -
ADDITION
MOMENTS (Maz and
May) : - -
TOTAL
DESIGN
MOMENTS : 7.64 34.51
REQD. STEEL
AREA : 1613.53 Sq.mm.
INTERACTION
RATIO: 1.00 (as per Cl. 39.6, IS456:2000)
CASE 2: MINIMUM
ECC. ABOUT Z CONSIDERED
DESIGN FORCES
(KN-M)
DESIGN AXIAL
FORCE (Pu) : 29.8
About
Z About Y
INITIAL
MOMENTS : 7.6 13.8
MOMENTS DUE TO
MINIMUM
ECC. : 0.60 0.00
SLENDERNESS
RATIOS : - -
MOMENTS DUE TO
SLENDERNESS
EFFECT : - -
MOMENT REDUCTION
FACTORS : - -
ADDITION MOMENTS
(Maz and
May) : - -
TOTAL DESIGN
MOMENTS : 7.64 34.51
REQD. STEEL AREA : 1613.53
Sq.mm.
INTERACTION RATIO: 1.00 (as per Cl. 39.6, IS456:2000
CASE 1:
MINIMUM ECC. ABOUT Y CONSIDERED
DESIGN FORCES
(KN-M)
DESIGN AXIAL
FORCE (Pu) : -6.8
About
Z About Y
INITIAL
MOMENTS : 0.8 0.9
MOMENTS DUE TO
MINIMUM
ECC. : 0.00 0.18
SLENDERNESS
RATIOS : - -
MOMENTS DUE TO
SLENDERNESS
EFFECT : - -
MOMENT REDUCTION
FACTORS : - -
ADDITION MOMENTS
(Maz and
May) : - -
TOTAL DESIGN
MOMENTS : 0.81 0.91
REQD. STEEL
AREA : 1130.97 Sq.mm.
INTERACTION RATIO: 0.03 (as per Cl. 39.6, IS456:2000)
CASE
2: MINIMUM ECC. ABOUT Z CONSIDERED
DESIGN FORCES
(KN-M)
DESIGN AXIAL
FORCE (Pu) : -6.8
About
Z About Y
INITIAL
MOMENTS : 0.8 0.9
MOMENTS DUE TO
MINIMUM
ECC. : 0.18 0.00
SLENDERNESS
RATIOS : - -
MOMENTS DUE TO
SLENDERNESS
EFFECT : - -
MOMENT REDUCTION
FACTORS : - -
ADDITION MOMENTS
(Maz and
May) : - -
TOTAL DESIGN
MOMENTS : 0.81 0.91
REQD. STEEL
AREA : 1130.97 Sq.mm.
INTERACTION RATIO: 0.03 (as per Cl. 39.6, IS456:2000)
CRITICAL
CONDITION : MAXIMUM AREA OF STEEL REQUIRED OF THE 4 CASES.
REQD. STEEL
AREA : 1130.97 Sq.mm.
REQD. CONCRETE
AREA: 140240.66 Sq.mm.
MAIN
REINFORCEMENT: Provide 6 - 16 dia.
(0.85%, 1206.37 Sq.mm.)
(Equally
distributed)
TIE
REINFORCEMENT: Provide 8 mm dia. circular ties @ 255 mm c/c
SECTION CAPACITY
BASED ON REINFORCEMENT REQUIRED (KN-M)
Puz : 1929.72 Muz1
: 59.85 Muy1
: 59.85
INTERACTION RATIO: 0.48 (as per Cl. 39.6, IS456:2000)
SECTION CAPACITY
BASED ON REINFORCEMENT PROVIDED (KN-M)
WORST LOAD CASE:
2
END JOINT: 65
Puz : 1952.34 Muz : 61.72 Muy : 63.12 IR: 0.46
