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

DESIGN AND ANALYSIS OF A HOSTEL BUILDING AT GUWAHATI ASSAM

Aim:

To carryout modelling, analysis, design, and preparation of construction drawings of a G+3 RCC building situated in Guwahati Assam.

Procedure:

• Initially open the Etabs software and then provide the grid and story information.

• Next we need to define the material property.i.e concrete(M25) and rebar(Fe415 and Fe500).

• Now, define section properties. i.e size of beams(400x500), columns(450x650) and thickness of slabs(150mm thickness) etc. Define --> section properties --> Slab properties. Also, define another slab for staircase as one way slab.

• After defining the materials next we need to place the components. First we need to place the frame elements and then slab elements.

• After placing the elements we need to define the load cases. Define --> load cases --> Provide DL, LL, Eqx, Eqx+, Eqx-, Eqy, Eqy+, Eqy-.

• Now, we need to assign these loads.
  • For live load take the value as 2kN/m2�2 with reference to IS875:part 2.
  • Take Brickwall load as 3.5kN/m
  • Floor finishes as 1.5kN/m2�2

• Next assign the joints.

• Also define the mass source and response spectrum function.

• Then define the load combinations.

• After that assign diaphragm to the shell.

• After that, we can carry out the analysis and design.

• After that we need to check for story drift for RSx and RSy whether it is within the limits or not as per IS1893.

• Hence, both the story drifts are within the codal limits.
• Next we need to carry out the concrete frame design and then extract the design results for beams and columns. Both flexural and shear rebar.

• Beam- longitudinal reinforcement

• Beam-Shear reinforcement

- The design result shows that 3 beams are failing in shear, hence inorder make it safe we need to increase the size of the beam. For 2 beams size have been changed to 450x650mm and for other beams size is kept as 450x750mm.

• Beam - Longitudinal reinforcement

• Beam - shear reinforcement

• Column - Longitudinal reinforcement

• Column - Shear reinforcement

• Hence the design is completed. Now, we need to export this Base reactions and load conditions in f2k format for footing design using SAFE software.

• Now, import the safe f2k file into the SAFE software. Hence all the reactions and loads have been imported to the software.

• Define the materials for concrete and rebars.

• Define slab properties.

• After that using draw point option drop the points for footing for each column.

• Now, go to draw option and draft points on footing for the piles to be developed.

• Next we need to provide pile, using the above used option and material property as pile500.

• Then place, the column along grid intersections.

• Define beam for tie beams.

• Now, we have to assign springs at these locations where piles are placed.
• For this we need to calculate the spring constant.
  • Spring constant= AE/L=196346.5⋅2500010000196346.5⋅2500010000=490873N/mm.
  • Then assign this spring constant.

• Now, define the load combination for serviceability limit and ultimate limit.

• Next, we need to check the design result.
  • Displacement values are within the limit, hence safe.
• 
  
  • Reaction check :
• 
  • Punching shear values are also within the range.
• 
• Now, we need to design the strip.

• Now, again carryout the design.
  • For strip layer A

• For strip layer B

• Hence, the design of footing is completed.