chluk2425
Civil/Environmental
- Nov 19, 2010
- 5
Hi everyone, I have a few question that had been bother me for quite a while that would like to ask for clarification from experts.
I understand the difference between membrane, shell and plate
1. I am modelling slab using membrane element, which this is what normally do. However I remember I had read somewhere that membrane slab has to be connected at 3or4 points only and it has to be a beam slab system. Why there is such a limitation? and, will membrane slab work with beam, wall slab system? What sort of thing should I pay attention when drawing the slab if beam wall slab system using membrane element is employed?
2. A shell element has both out and in plane stiffness, and shell element will not be mesh automatically; a membrane element has only in plane stiffness, and will be mesh automatically. If, I model the slab, using shell element, BUT, modify the stiffness M11 and M22 to very small (1e-3), and goose automesh at beam joint line, will there be any difference between the outcome if I use membrane to model it? I know it sounds stupid when you can model such property easily by using membrane, but I ha read somewhere that there are many constrains when drawing slab using membrane producing inaccurate result, and the better way to avoid suh problem is to use the more compicate method I mentioned above.
Please clarify my worries.
Thank You
I understand the difference between membrane, shell and plate
1. I am modelling slab using membrane element, which this is what normally do. However I remember I had read somewhere that membrane slab has to be connected at 3or4 points only and it has to be a beam slab system. Why there is such a limitation? and, will membrane slab work with beam, wall slab system? What sort of thing should I pay attention when drawing the slab if beam wall slab system using membrane element is employed?
2. A shell element has both out and in plane stiffness, and shell element will not be mesh automatically; a membrane element has only in plane stiffness, and will be mesh automatically. If, I model the slab, using shell element, BUT, modify the stiffness M11 and M22 to very small (1e-3), and goose automesh at beam joint line, will there be any difference between the outcome if I use membrane to model it? I know it sounds stupid when you can model such property easily by using membrane, but I ha read somewhere that there are many constrains when drawing slab using membrane producing inaccurate result, and the better way to avoid suh problem is to use the more compicate method I mentioned above.
Please clarify my worries.
Thank You