Reinforcement Detailing of Beams from ETABS output

QUESTION:-

Detail design of beams in Etabs 2018.
The ETABS file for a G+4 building is provided. Run the analysis and design the RCC Moment ResistingFrame. The following challenge deals specifically with two continuous beams in the 1st floor.

1) 3 span continuous beam along grid A
2) 7 span continuous beam along grid 3

Address the following issues thereafter.
• Provide details of longitudinal and shear reinforcement for the two continuous beams. Sketch the beam elevation details or draft it using autocad software. A sample of how beam elevation details is prepared in consultancy firms is provided below. Participants can prepare it as per their preference:

• Calculate value of the maximum shear force in any one of the spans in the continuous beams, as per clause 6.3.3 (b) in IS 13920 – 2016. Also, confirm these values from shear force demand calculated by ETABS.Please note that if longitudinal reinforcement provided is more than required (as per ETABS results), the shear force demand will vary from what is provided by ETABS.

ANSWER:-

Aim:- In order to design the beams in minute detail using Etabs 2018. To offer specific information on the longitudinal and shear reinforcement for the two continuous beams that have been provided. to compute the maximum shear force that may occur in any one of the beam's spans when the beam is in its continuous state.

Introduction:-

• The horizontal structural components known as beams are those that are utilised for the purpose of sustaining lateral loads.
• Beams typically receive weight from the floor slab in traditional reinforced concrete buildings.
• However, beams may also be subjected to additional loads such as wall loads, finishes, installation of services, and so on.
• When designing and specifying RC beams, it is necessary to pick the appropriate beam size in addition to the amount of longitudinal and shear reinforcement needed to meet both the ultimate and the serviceability limit state criteria.
• After that, it is very essential to ensure that the beam reinforcements on the site are put and organised in the appropriate manner so as to prevent errors in the building.

Procedure:-

Step:-1

• First we have to open the challange 7 page and download the challenge.
• After downloading the Challenge open it in the etabs 2018, as shown below.

Step:-2

• Next we have to check the load combinations, as shown below.

Step:-3

• Next we have to start the beam design by selecting the 'Start Design/Check' option, as shown below.

Step:-4

• After the completion of the beam design, we need to select the 'Display Design Info' option, as shown below.

• After selecting the 'Display Design Info' option the new tab appears, In that we select the Longitudinal Reinforcing in the Design Output and click on the OK button, as shown below.

• Next the longitudinal reinforcement details will appear, as shown below.

Step:-5

• Next we need to draw the Reinforcement diagram of 3 span continous beam along Grid-A, and also need to provide the reinforcement details.
• The maximum Ast for the bottom support is 1766mm2��2 and bottom middle is 702 mm2��2
• The maximum Ast for the top support is 1889mm2��2 and top middle is 453 mm2��2
• Now we provide 3-28ΦΦ at the top and bottom, as shown in the below figure.
• Next we provide 1-8ΦΦ at the top supports for the continuous beam, as shown below.

Step:-6

• Next we need to draw the Reinforcement diagram of 7 span continous beam along Grid-3, and also need to provide the reinforcement details.
• The maximum Ast for the bottom support is 1061mm2��2 and bottom middle is 1493 mm2��2
• The maximum Ast for the top support is 1915mm2��2 and top middle is 479 mm2��2
• Now we provide 3-22ΦΦ at the top and bottom, as shown in the below figure.
• Next we provide 1-10ΦΦ and 1-12ΦΦat the top supports and we provide 2-16ΦΦ at the bottom middle for the continuous beam, as shown below

Step:-7

• After providing the beam reinforcement details, we select the beam and right click on the beam then the new tab appears, as shown below.
• Next we need to click on the Details option in Concrete beam design tab, as shown below.

• Next the Shear details will be visible, as shown below.
• As per the clause 6.3.3 the design force is 232 kN.
• We got, Maximum Shear force = 174.11 kN.

RESULT:-

• Through the use of the Etabs programme, the beams have been effectively designed in minute detail.
• You have provided the specifics of the longitudinal reinforcement as well as the shear reinforcement for the two continuous beams.
• And moreover, using the Etabs programme, we determined the value of the maximum shear force present in the continuous beams.