Reinforcement detailing of Columns from ETABS output

AIM & INTRODUCTIION :

AIM :

To provide details of longitudinal reinforcement for the two columns 3A and 3B, from foundation to terrace level then run the analysis and design the RCC moment resisting frame.

INTRODUCTION :

• In E-TABS the stuctural members such as beams, columns and slabs can be created and analysed its bending moment and shear force.

• We can Run the Concrete Frame Design fo the created structure to provide required both Longitudinal and shear reinforcement bars automatically.

• The values for the created structures can be automatically calculated by E-TABS.

• Here in E-TABS we can know the number of Reinforcement bars should be provided for the concrete structures.

• From Frame design analysis we can see both Top and Bottom reinforcement figures for each beam sections.

• Also we can display concrete frame design result for Shear reinforcement.

• Moreover we can view the concrete beam design information as per IS 456:2000.

• The Design details of the overall structures can also be viewed as Summary, Flexural Details, Shear Details, Envelope.

PROCEDURE :

• First open the E-TABS software then click Open Existing Model and open challenge 7 file.

• After opening of the existing file named challenge 7, click File and Save As to save the file as Challenge 9.

• Then save the file as name of Challenge 9 in appropriate folder and click Save.

• To view the model from the Terrace level, select Plan option the toolbar and select Terrace from the select Plan View tab and click OK.

• Then select the two columns 3A and 3B as per the question requirement.

• Then right click on the screen of the workspace and select Show selected objects only to see the selected two columns.

• Here we can see the plan showing only the selected two cloumns 3A and 3B.

• Click the Set Default 3D view tool in the Toolbar and we can see the 3D view of the columns.

• Now click Run Analysis tool at the Toolbar to start analyse the showing columns.

• Followed by click and select Concrete frame design tool at the toolbar above to check .

• After the Checking the Concrete frame design, we can see the Longitudinal Reinforcement members of the two columns.

• Click Elevation tool at the toolbar above then select Elevation - 3 and click OK to see it elevation view.

• Now to see the Shear Reinforcement of the Column concrete frame design.

• Then click the downward arrow next to the concrete frame design tool and select Display Design Information.

• In the Display Concrete Frame Design Result tab from Design Output select Shear Reinforcement and select OK.

• After selecting and applying the Shear Reinforcement for the columns then we can see the Shear Reinforcement values.

RESULT :

• The ETABS file for a G+4 building is provided. Run the analysis and design the RCC Moment Resisting Frame. The following challenge deals specifically with two columns at the following grid intersections.

1. ) LONGITUDINAL REINFORCEMENT AND SHEAR REINFORCEMENT OF COLUMN AT GRID - 3A FROM ETABS :

2. ) LONGITUDINAL REINFORCEMENT AND SHEAR REINFORCEMENT OF COLUMN AT GRID - 3B FROM ETABS :

• Provide details of longitudinal reinforcement for the two columns, from foundation to terrace level. Sketch the column cross sectional & elevation details or draft it using autocad software.

1. CROSS SECTION & ELEVATION DETAILS OF COLUMN - 3A :

2. CROSS SECTION & ELEVATION DETAILS OF COLUMN - 3B :

• Show shear reinforcement & lapping details as per special confining reinforcement provision of clause 8.1 of IS 13920 - 2016.

`l_0` IS NOT LESS THAN

a) Larger column dimension.

b) `1/6` of clear span of column. 650mm

c ) 450 mm.

CONFINEMENT SPACING NOT MORE THAN

a) `1/4` of smaller column dimension.

b) 6 times of diameter of column size.

c) 100 mm.

THE AMOUNT OF CONFINEMENT REBAR

`A_s__h` = Maximum of `[[0.18 s_v h f_ck/f_y.(A_g/A_k-1)],[0.05 s_v h f_ck/f_y]]` `169 mm^2`