Revision 1 posted to RAM | STAAD Wiki by Madhuri Panda on 4/9/2019 11:11:57 AM
- Can RCDC design Curved beams? Will it convert the curved beam composed of many parts to a single physical beam?
- Yes. If curved beam is modelled in sufficient small parts then RCDC identifies it as single beam as per the geometry and support conditions. The beam is designed for Bending, shear and torsion as per regular beam.
- Can RCDC provide bottom bar without curtailment in single span?
- RCDC has the option of detailing bottom reinforcement as Best fit and Max dia. user can use option of Max diameter to maintain the same number of bars at bottom most layer. For Best fit it curtails the bars at support if it is allowed as per detailing requirements.
- Can number of bars for the given width of beam be edited?
- Yes, User can set the number of bars as per width of section in "zone bar setting" option. It also checks the minimum and maximum spacing criteria at the same time. For more information refer Topic “Preferred Bar Spacing” for beam from help Content.
- Can RCDC provide the detailing of beam with lowest diameter throughout the length and balance area of steel with higher diameter in other layer?
- Yes. It can handle this only for top reinforcement. To maintain the lowest bar at top user can select “min dia.” option in general setting. Lowest Bar diameter and numbers will be provided across the length of the beam and remainder will be provided at next layer of reinforcement. This option will result in detailing like 2-T12 at first layer and 2-T25 at second layer. For more information refer Topic “General and Reinforcement Settings” for beam from help Content.
- Does RCDC allow to provide only 2 bars for top reinforcement?
- The Number of Bars suggested by RCDC are as per beam width and maximum spacing criteria given in codes. User can change the numbers of bars prior to design subjected to spacing criteria given in code. For zero bending moment zone RCDC can provide minimum two bars with minimum bar diameter. For more information refer Topic “Preferred Bar Spacing” for beam from help Content.
- What is the purpose of mirror & straight option in group/ungroup tab?
- Mirror grouping option can be used if beams are mirror in arrangement with same geometrical properties. So beam on one side can be mirror in detailing of the beam on other side. Similarly if beams are identical in plan i.e. beam geometry is similar at a given level and repetitive then these beams can be grouped. For more information refer Topic “In Plan Grouping” for beam from help Content.
- Why specifically only 13 stations (for beams) can be imported from E-tabs to RCDC?
- 13 stations divides the element in to twelve parts. As per standard practice of all codes, curtailments of reinforcement lies at L/4, L/6 and L/3 of span where L is the span of the element. Dividing the element in to 13 station satisfies all the requirements of curtailments. Curtailment of reinforcement helps in beam detailing thus it is mandatory to provide 13 stations to all beams in the analysis. Staad automatically provides the results at 13 stations. E-tabs can provide results at any stations as per user requirements Thus in E-tabs user has to assign output stations as 13 before exporting the results. For more information refer topic “Technical Discussion” of beam and Column from help Content.
- Side face reinforcement (SFR) is designed for beams even though the depth is less than 750mm, whether there are any options to enable/ disable side face reinforcement?
- In RCDC, SFR is calculated as per design requirements including torsion. User can provide the SFR even it is not required in design. In many cases for beams with depth less than 750 mm, there may be torsion, which would result in SFR. User may check the detailed calculation report for clarification.
- Please give clarification of failure type for beam element. Failure type – Shear –Tc max
- Tc max failure means Tv exceeds the maximum permissible shear stress.
- Even after opting best fit for top reinforcement, why does RCDC provides higher reinforcement (as per minimum Pt) at top at mid-span?
- This would be typically doubly reinforced section which causes more reinforcement at top even when moment at that location is nominal. In the calculation report it can be clearly checked where Asc-required at mid-span is captured. This is the top reinforcement required at that section.
- Why default 0.2% is provided for nominal steel in RCDC? Does it have any reference?
- RCDC provides the nominal steel where bending moment is ZERO. Default value provided in RCDC for nominal steel is 0.2 %. This is an approximate Value and we have kept the value close to minimum steel in beam. The above value is editable and can be put as per user requirements. For zone with no Bending Moment, RCDC uses nominal steel and for detailing, it would adopt 2 bars with minimum diameter possible.
- Is there any option to disregard the contribution of concrete in resisting shear for beam when IS: 13920 is used?
- No. Beam shear design is as per IS 456. Shear induced due to Sway action is calculated as per IS 13920. For Sway shear also the part of shear is arrived from the dead and live load. Thus RCDC does not allow to ignore the concrete for shear design.
- When IS: 13920 is selected, does RCDC consider required rebar or provided rebar to calculate capacity (plastic) shear force (or moment capacity) for beam?
- Yes. RCDC designs the beam shear as per Clause 6.3.3 of IS 13920 and consider the reinforcement provided to calculate the moment capacity. For more information refer Topic “Calculation of Ductile Shear” for beam from help Content.
- Does RCDC calculates moment capacity for sway shear calculations as per rectangular section or flanged section for beam?
- For moment capacity of section RCDC always considered as a Rectangular section as Flange section is not applicable at support. Also to get the flange action, flange has to at compression side which is not the case at support. For more information refer Topic “Flanged Beam” for beam from help Content.
Tags: is, RCDC, SFR, beam, Flange