Analysis & Design of RCC shear walls in the model using ETABS

• Aim:

• To review the supplied Etabs model
• To gather design details of the model.
• Resolve the said issues in the model
• To follow suggested parameters.

• Procedure:

• As like the week 7 and 8 challenge we are going to take the existing supplied model.
• In week 7 and 8 models we were modelling for columns and beams with a G+4 building.
• Whereas in week 9 we are suppplied with a G+5 building where we have to model for shear wall design.
• Hence as like before we are inserting the existing model into the software.
• After inserting the model into the ETABS software we are going to process the suggested analysis.
• In the inserted model we need shear wall design
• Hence we are picking up the specified shear wall as specified in the challenge.
• The shear wall picked is in the grid 11
• Picking the shear wall is by selecting all stories option to select all the shear walls in the specified grid.
• The selected shear walls are shown below.

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• Let us view the elevation of the shear wall picked up.

• And the next thing we will be checking before the analysis is the pier label assignment in the shear wall.

• After the selection of the shear walls and checing the necessary data we are going to run the analysis.
• After the analysis we ge the report of the model.

• After this the model is taken to shear wall design.
• The shear wall design is shown below.
• Which shows the pier longitudinal reinforcing

• After this we will see the pier Edge/boundry zone reinforcing

• After this the Pier shear reinforcing is shown

• After the reinforcing detail extraction we are set to drafting the reinforcement design drawing.
• So before that let us view the elevation so that we can draw through the whole building with story heights.

• After the reinforcing details we are begining with teh specification and guidelines check on the design of the shear wall.

• Classification of shear wall as per IS 13920-2016 Clause 10.1.4

Slender wall

h_w / L_w = 21000/1500 = 14>2

• Min. net vertical reinforcement as per IS 13920-2016 Table-1

= 0.0025+0.01375(300/1500) which we multiply with the top view of the wall as it is vertical reinforcement we get

= 2363mm^2

• Min. Vertical reinforcement within boundary element table-1

1440mm^2 on left (600mm width boundary element)

1080mm^2 on right(450mm width boundary element)

• Minimum horizontal reinforcement in shear wall per IS 13920-2016 Table 1

(ρ_h)_min = 0.0025 + 0.5((h_w/L_w)-2) (ρ_h – 0.025)

ρ_h = 750/(300*1000) = 0.0025

h_w = 21000

L_w = 1500

(ρ_h)_min = 0.0025 + 0.5 (21/15 – 2) *0

(ρ_h)_min = 0.0025 which is the same 750 mm²/m

• Max dia of the rebar for shear wall as per IS 13920-2016 Clause 10.1.8

1/10th of wall thickness = 300/10 = 30mm

where commercial rebar dia used to be 25mm which can be adopted

• Confining reinforcement spacing for boundary elements as per IS 13920-2016 Clause 10.4.4

1. 1/3 of min member dimension = 300/3 =100mm
2. 6 times smalles main rebar = 6*25=150mm
3. 150mm permissible if vertical bars are spaced at maximum 200mm

max spacing of confining reinforcement in boundary element 150mm

• Confining reinforcement within boundary element as per IS 13920-2016 Clause 10.4.4

A_sh = 0.05 S_v h f_ck/f_y

S_v = 150mm, h= 1000mm

A_sh = 452mm²

• With the above procedure we are detaining the reinforcement of the shear wall.
• The drafting is done in autocad and is shown below

• Result:

• The model was inserted.
• Resolutions was derived.
• Required design details of teh shear wall was shown
• The required details and drawing were shown