Create circular beam from structure wizard. It is nothing but a combination of a series of small chords as per command given by the user for number of bays and radius in the dialogue box. For creating semi circular beam the angle can be chosen as 180 degree otherwise 360 degree cor circular beam. The beam so created is very close to circular beam. Staad calls the beam so created as circular beam with several nodes on the circumference. Now one should be ready to create 3 noded plates, two adjacent nodes on the circumference and the 3rd one at the centre. Hereafter with circular repeat command all the remaining plates can be created one after the other or in one stroke also as per command given in the circular repeat dialogue box.
TO SIR SURESHPRSHARMA:
sir Ive done this methods creating a curve beam, but when i process it through staad pro rc designer it seems the RC designer will not include this beams in the design and also have an have a result of beam not supported fail. how should be done in rc designer im using ACI 318 - 05 on the brief.
You are very correct Sir. RC designer will not design circular beam which is nothing but a combination of many chords of a circle. For RC designer it is essential that the beams forming member should be collinear in order that a member could be formed. However Staad pro, I trust will give you design for the various segments of the beam from which a common reinforcement design for the beam can be created. In fact circular plate and beam according to me should be used for modeling and loading the structure but not for designing.
I call upon other members too, who are not in agreement with me, to offer their opinion to help me as also the member who initially raised the query.
thank you sir,
i have also a problem with rc designer, i dont know if something wrong with my model but the beam which supported beam/girder i mean beam not directly supported with column have a result with "not supported" the it assumes to be fail, however,if you compute it manually the beam pass the requirements.
In my view there is no need to worry about " No support". Suppose you have a beam AB, supported at A and B on column. Subsequently three nodes have been created on the beam AB due to meshing of plate and those nodes are 1 2 and 3. In the beam support table of RC designer node 1 2 and 3 will be reported as No Support after running the design in RC designer. What is wrong in this? Staad looks for support at every node. When it does not find a column support for the beam at a node it reports as No Support. It does not mean that beam has failed. It simply means that there is no support at the node meaning thereby that Staad advises you too to verify whether you need to have a support at the node. If RC designer reports reinforcement in the Rft lay out for the beam it means the beam passes for the reinforcement reported by the designer and fails for the reinforcementreported by staad earlier. It generally happens at support for hogging moment because staad designs each beam between the two nodes as independent beam and does not account for continuity whereas RC designer does.