And penthouse. A core wall and four-bay SMFs at the perimeter of building on all sides. This building is Model2B of peer case study on tall buildings article. I have validated my model with there results. However when I try to change the building from rigid diaphragm to semi-rigid, I have a lot of converging issue for strong ground motions. I am using ShellMITC4 with FiberPlateSection since I need different stiffness modifier factor for shear and flexure. Now I have 50%EI in-plane stiffness. 100%GA for shear and 40%EI for out of plane stiffness. The problem is when I make the out of plane stiffness smaller the model start to converge! Here is part of the code that I used for modeling slab material. I am using ElasticOrthotropic material so that can have different material modifier factor for In-plane and out-of-plane flexure and shear.
I am using half the thickness. But to get the correct stiffness, I have 100%E for In-plane. 320%E for out of plane so that I can get total 40%EI. And 200%G so that I can have 100%GA in final.
I know this is very messy, but it is the only way that I can fix my convergence issue! But still some of the strong ground motions do not converge, and it does not give me any reason why! Could you please help me! I need to finish my thesis as soon as possible!
Thanks
set PentHouse_1 14;
set Roof_1 15;
set Floor_20_1 16 ;
set Floor_2nd_1 17 ;
set Floor_46_1 18 ;
set Floor_30_1 19 ;
set PentHouse 2660;
set Roof 2661;
set Floor_20 2662 ;
set Floor_2nd 2663 ;
set Floor_46 2664 ;
set Floor_30 2665 ;
set Ec 4592;
set Ex $Ec
set Ey [ expr 3.2*$Ec ];
set Ez [ expr 3.2*$Ec ];
set vxy 0.2;
set vzx 0.2;
set vyz 0.2;
set Gc 1913.33;
set Gxy [ expr 2*$Gc] ;
set Gyz [ expr 2*$Gc ;
set Gzx [ expr 2*$Gc] ;
##nDMaterial ElasticOrthotropic $matTag $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx <$rho>
nDMaterial ElasticOrthotropic $PentHouse_1 $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx [ expr 2*0.0000005106 ]
nDMaterial ElasticOrthotropic $Roof_1 $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx [ expr 2*0.0000007024 ]
nDMaterial ElasticOrthotropic $Floor_46_1 $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx [ expr 2*0.0000006585 ]
nDMaterial ElasticOrthotropic $Floor_30_1 $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx [ expr 2*0.0000006673 ]
nDMaterial ElasticOrthotropic $Floor_20_1 $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx [ expr 2*0.0000007024 ]
nDMaterial ElasticOrthotropic $Floor_2nd_1 $Ex $Ey $Ez $vxy $vyz $vzx $Gxy $Gyz $Gzx [ expr 2*0.0000007375 ]
##section PlateFiber $secTag $matTag $h
section PlateFiber $PentHouse $PentHouse_1 4
section PlateFiber $Roof $Roof_1 5
section PlateFiber $Floor_46 $Floor_46_1 4
section PlateFiber $Floor_30 $Floor_30_1 4
section PlateFiber $Floor_20 $Floor_20_1 4
section PlateFiber $Floor_2nd $Floor_2nd_1 4