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RAM Concept Shear Reinforcement Section Design

JT — Mon, 27 Feb 2023 03:23:02 GMT

Hi,

I'm trying to get a deeper understanding of why RAM Concept is showing my shear requirement as being larger than the same beam I have modelled in RAPT to verify. RAPT does not require any additional shear reinforcement. I have checked the shear core and that seems to be OK.

As an example, I have been looking at design section 24C-2, section 2 in the model I have uploaded via secure link and have the following questions:

1. Why is the design section minimum demand (-1427kN) significantly larger than the design strip maximum shear in this span (-533kN)? What does the design section demand mean?

2. From the cross section audit Envelope 7 of the Final Design Check for Strength design, phi Vuc = 0.75 x 2043kN = 1530kN > 1427kN. Why is shear reinforcement added when capacity > demand and what determines that they need to be closed ligs?

3. Why is there bottom reinforcement required at the column at this location rather than at mid-span if anywhere? Similar question applies to the beam in the north-eastern corner of the building.

Regards

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Mon, 27 Feb 2023 00:45:15 GMT

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RAM Concept - Load History Deflections Not Converging

Stacey Klein — Mon, 01 Jun 2020 06:56:15 GMT

Hi,

I have two RAM Concept suspended slab models which will not converge when running the load history deflections and I am at a loss as too why. Below is the warning provided in the Load History Calc Log:

WARNING: An error has been found while calculating load history deflections. The load history deflection solution did not converge. The expected deflection error is 1.803 mm

Information which may be helpful:

Suspended slab minimum thickness 600mm
Models of Basements 4 and 5 - Walls all around with internal columns
- Models of Ground to Basement 3 are very similar and do converge
- I am unsure if this is purely coincidental but the columns change from rectangular in G-B3, to circular in B4 and B5.
Calc Option Parameters are in screen shots

Changes made to try and resolve issue

Iterations to use increased to 20 (both under zero-tension and load history)
Checked with user only reo and with program reo
Fixed meshing warning of some wall centrelines not joining
- Models of Ground to Basement 3 have the same warnings and do converge

Are you able to provide any guidance on how I may be able to get these models to converge in order to get accurate load history deflection results?