Project 2_Design & Analysis of a Hostel building at Guwahati, Assam

DESIGN & ANALYSIS OF A HOSTEL BUILDING AT GUWAHATI, ASSAM

AIM:

To model, amalyse and design of G+3 Hostel building in ETABS and Foundation in CSI SAFE.

INTRODUCTION:

• Location – Guwahati, Assam
• Function – Hostel block in an academic institute
• The walls will be made of AAC blocks. Other loadings are to be calculated as per the architectural drawings.
• The buildings rests on type 3 soil. Piles of length 10 meters and 500 mm diameter with a load-carrying capacity of 280 KN is to be used.
• The ground floor level will be at a height of 2 meters above the existing site level to avoid floodwater enter the building.
• M25 grade of concrete with Fe500 for longitudinal reinforcement and Fe 415 for shear reinforcement is to be used.
  
  
  

PROCEDURE:

• Firstly before start modeling in etabs we nned to prepare grid drawinging for easy and fast modeling in ETABS
• Using the given architectural drawinf prepare rough grid lines with accurate measurements in AutoCAD
  
  
  
  
  
  

• First we have open the etabs software.

• Then click on the New model option at the left side to create the new model, as shown below.
  
  
  
  

• After that model initialization window will peompt, we have to select 'Use Built-in Settings with' option, as shown below
  
  
  
  
• Then choose grid only to create grids, to add grids click on edit grid data
  
  
  
  
• Enter the X and Y grid data use add button to add extra grids and enter their respective distance
  
  
  
  
• Then click on edit storey data to add number of story and story height
  
  
  
  
• Enter the required number of story and their height then click ok
• After entering all details and creating the requiries story then click ok
  
  
  
  
• This is the first etabs user interface. In the left side its the plan view and in the right side its 3d view
  
  
  
  
• Firstly need to define the material properties, so click on material properties to in define from menu bar to define the material properties
• To add new material property click on add new material
• Then in the opened window select the desired material properties and click ok to create the material
• Then it opens the detailed material property data
  
  
  
  
• In the similar way create rebar material and click ok
  
  
  
  
  
  
• After creating all the material properties click ok to finish
  
  
  
  

• After creating the material properties need to define frame sections

• To create frame sections go to define and click on frame section in section properties

• To define new frame property click on add new property
  
  
  
  
• Slect the rectangular section then click ok
  
  
  
  

• Enter the property name for each frame sections and choose the material grade

• Enter the depth and widt of the sections

• click on modify rebar data to specify the rebar data
  
  
  
  

• In that choose design for baem if its a column section then choose column

• For this section its a beam so click on beam and enter cover details

• Also specify the rebar materilal from the dropdown selection

• After entering all the details click ok

  
  
  
  
  

• click on property modify to modify the beam peoprty

• Enter the details as shown in below image
  
  
  
  

• In the same way create another beam section with respective property name and all the details
  
  
  
  
  
  
  
  

• After adding all the frame properties click ok to finish
  
  
  
  

• Then need to define slab sections

• For that go to define and select slab sections in sections peroperties

• click on add new property

• Add peoperty name for slab

• Select the slab material

• And choose modeling type as membrane

• Then enter the thickness of the slab

  
  
  
  
  
  

• Create anothe slab by clicking add new property

• Then click ok to to finish defining slab sections
  
  
  
  

• To define load pattern click on load pattern on in define in menu bar

• click add to add the new loads

• Select the type of load and code from the dropdown

• After add all the load types click ok to finish

  
  
  

• After defining all the sections, materials and load patterns need to start modeling

• First to ceate columns click on quick draw column in the left side window

• Befire that make sure the work mode is switched to all stories

• Then select the column property to draw and draw the columns as per their respective positions

  
  
  
  
  

• In the same manner create the beams by clicking quickdraw beams in left side panel

• The beams need to draw in all stories mode

  
  
  
  

• To rotate the columns select the columns in the window

• Then go to frame and click on local axes to rotate column

  
  
  
  
  
  
  

• Enter the angle in degree to rotate

• Then click ok to rotate the column

  
  
  
  
  

• All the column orientation is updated

• cross check again to confirm

  
  
  
  
  
  
  
  

• In the mumpty level draw the slab and assign one way load distribution on stair
  
  
  
  
  
  

• Side vie and 3d view
  
  
  
  

• Elevation view
  
  
  
  

• To assign the loads now need to select frames

• The wall load is acting only on frames so selct the frames

• The frames are selectes by using object type

  
  
  
  
  

• select beams and click select

• Now all the beams are selected

• Go to assign, click on distributed load in frame loads in frame load

  
  
  
  
  
  
  
  
  
  

• The assigned load will be visible in the given image
  
  
  
  
  
  
  

• Select all the base joints and assign pinned connection
  
  
  
  

• To define the load combination, go to define and click on load combinations

• click on add default design combo

• Then slect concrete frame design and shear wall design to add load combinations

• Also click on convert to user combination to edit them

  
  
  
  
  

• After creating all the load combinations click ok
  
  
  
  

• For slabs we need aggign the diaphragms

• Select the slabs using object selection

• Then go to assign shell and click on diaphragms

  
  
  
  
  

• The assigned mass source is visible
  
  
  
  

• Create mass source data
  
  
  
  

• Click ok to finish
  
  
  
  

• After assigning all the loads need to check the model for error

• Click on Check model in analyse tab

• Click on select alland click ok
  
  
  
  

• After checking it shows no error if error found then need to correct them
  
  
  
  

• Then click on run analysis
  
  
  
  

• Check the storeydrift
  
  
  
  
  
  
  
  
  
  

• Go to display and click on show tables to view results

• Select modal periods and frequencies to view results
  
  
  
  

• Now the Modal Participating Mass Ratios table will be visible, as shown below.

• The building has no irregularity

• The natural time period of building is 1.396 sec
  
  
  
  

• After successful completion of analysis then click on concrete frame design.

• In the concrete frame design click on start design/check.

• After completion of design check it will display the longitudinal reinforcement details.

• Then Switch to First floor plan view to view the longitudinal reinforcement results.
  
  
  
  

• Verify all members passed in design
  
  
  
  

• No members were failed so continue to produce detailing and drawing
  
  
  
  
  
  
  

• Selected span concrete frame design data
  
  
  
  
  
  
  
  
  
  
  
  

• Longitudinal and Shear reinforcement details
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

• To export load data to safe click export and select .f2k
  
  
  
  

• Select base story and check export floor loads and loads from above
  
  
  
  

• Open the SAFE software and go to file menu and click on select New Model to create new file

• Then click on import to import .f2k file exported from ETABS
  
  
  
  

• The imported file is now visible
  
  
  
  

• Check the loads
  
  
  
  

• Firstly need to define the materials

• To define material properties go to define and click on materials

• Click on add new materials to add materilas to the existind materials

• Enter material name and data and click ok
  
  
  
  
  
  
  

• After finishing all material creation click oj to finish
  
  
  
  

• Then define slab properties
  
  
  
  
  
  
  
  

• After defining all click ok
  
  
  
  To design pile cap

• Column size = 450 x 600 mm

• Pile length = 10 m

• Pile diameter = 500 mm

• Pile capacity = 280 kN
  

• Elastic modulus of M25 concrete = 25000 N/mm2
• Area of each pile = 196349.5 mm2

• Spring constant = `(25000*196349.5)/10000 = 490.8` kN/mm2

• Click on draw slab and and select property to draw column, pile cap and pile
  
  
  
  
  
  
  
  
  
  
  

• Select all pile points to assign point spring
  
  
  
  

• Then click ok to assign
  
  
  
  

• The assigned point spring is visible
  
  
  
  

• Plan view of pile group
  
  
  
  

• Create load combinations
  
  
  
  
  
  

• Click run analysis
  
  
  
  

• The deflection is within limit, hence safe

  
  
  
• As all the pile reaction forces are according within the limit.
• The pile reaction forces not exceeding 280 kN, Hence safe
  
  
  
  
• Also, all the punching shear values are less than 1, So its safe
  
  
  
  
• Flexural reinforcement details
  
  
  
  
  
  RESULT
  
  The G+3 Hostel building is modeled, amalysed and designed using ETABS and Foundation in CSI SAFE.