ARPIT CHAWLA 's Communities Activities

RCDC Beam design - effective depth Calculation

ARPIT CHAWLA — Tue, 11 Jan 2022 12:27:39 GMT

Bentley Team,

How is the effective depth for beam being calculated for a beam with two or more numbers of layers in RCDC software?

Please provide the basis and validation for the same.

I could find some formula related to effective depth in FAQ in the link below, but that is not giving correct value for the design I have.

https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/41953/rcdc-beam

RCDC -Column Design as per IS 13920

ARPIT CHAWLA — Thu, 27 Jan 2022 11:42:29 GMT

Hi,

I am unable to use joint check option in ductile column design in RCDC. The option is greyed out. Refer to screenshot below. What could be the possible reason for it.

Note: I already have run and designed all the beams in the model.

/resized-image/__size/320x240/__key/communityserver-discussions-components-files/5932/Screenshot-_2800_1037_2900_.png

RCDC - Beam Design with ACI 318M-14 - Crack Width Calculation

ARPIT CHAWLA — Sat, 15 Jan 2022 11:42:36 GMT

Dear Bentley team,

I encountered an issue regarding crack width calculation in RCDC with ACI 318M-14 code, described as follows:

Refer to the outputs attached below. The considered beam is B5 and Zone is Top right.

When beam is designed with permissible crack width set as 0.25mm, then actual crack width with 1 layer of bar with 3 no. of 13 dia bars is coming out to be 0.1539mm which is within the limit.

Now for the same design if I restrict the permissible crack width to 0.2mm, then also it should satisfy the design (as 0.1539mm < 0.2mm). But when I reduce the limit to 0.2mm, RCDC is increasing the rebar to 2 no. of layers with 3 no. of 13 dia bars in first layer and 2 no. of 13 dia bars in second layer.

Changing only the permissible crack width limit should not ideally affect the actual crackwidth calculation. But it is somehow dependent on that and leads to increase in rebar. Please help in rectifying the issue.

Please find attached RCDC file, and two output sheets with maximum crack width set as 0.25mm and 0.2mm for your reference

. communities.bentley.com/.../Regular-Beam-Design-_2D00_-ACI-318M_2D00_14-_2D00_-Max-CW-_2D00_-0.20mm.pdf communities.bentley.com/.../Regular-Beam-Design-_2D00_-ACI-318M_2D00_14-_2D00_-Max-CW-_2D00_-0.25mm.pdf communities.bentley.com/.../FMO_5F00_P01_5F00_01_2800_02.12.2021_29002D00_NV_2D00_2_2D00_Beam_2D00_1_2D00_0-m.rcdx.7z

STAAD RCDC, Ductile shear calculation in beam design as per IS code

ARPIT CHAWLA — Mon, 03 Jan 2022 09:43:18 GMT

Issue 1:

In RCDC, for Beam ductile design using IS code, how is the ductile shear being calculated?

I have referred to RCDC help file as well as RCDC Beam FAQ (Q.31) given in the link below.

https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/41953/rcdc-beam

I am able to grasp the technical intent, but unable to validate the formulas as the values which I am computing using given formulas (refer below) are not matching with the RCDC output.

I also tried to find validation sheets for ductile beam design using IS code, but its not available. Only Non-ductile beam design validation is available.

I am also attaching a typical design for reference and and would appreciate if calculations using the same reference can be demonstrated.

Issue 2:

While transferring loads from STAAD to RCDC for beams, the loads are not transferred exactly. Some deviation (although not significant) is observed in them. What could be the probable reason for the same?

communities.bentley.com/.../Plinth-Beam-B5_2C00_-B6-_2D00_-RCDC-Summary-Output-_2D00_-Ductile-Beam-_2D00_RCDC-Portal.pdf

Ask A Question I

Mon, 03 Jan 2022 07:11:01 GMT

Ask a question in a forum.