I made a portal frame arrangement with 3 columns in x axis and 3 columns in z axis, 2 levels (Y-axis) are also provided. All separations are 4 m. Beam and column sizes are given as 0.5m x 0.5m concrete. Then I added 0.25 m offset (specifications) in all the beams. Self weight and floor load of 3.75kN/m2 is given in loading. The analysed file is not symmetric. The symmetric beams doesn't have same moment distribution. The staad input file is given below. Please explain me the what I am doing wrong.
STAAD SPACESTART JOB INFORMATIONENGINEER DATE 23-Feb-21END JOB INFORMATIONINPUT WIDTH 79UNIT METER KNJOINT COORDINATES1 0 0 0; 2 4 0 0; 3 0 0 4; 4 4 0 4; 5 0 4 0; 6 4 4 0; 7 0 4 4; 8 4 4 4;9 0 8 0; 10 4 8 0; 11 0 8 4; 12 4 8 4; 13 8 0 0; 14 8 4 0; 15 8 0 4; 16 8 4 4;17 8 8 0; 18 8 8 4; 19 0 0 8; 20 0 4 8; 21 4 0 8; 22 4 4 8; 23 0 8 8; 24 4 8 8;25 8 0 8; 26 8 4 8; 27 8 8 8;MEMBER INCIDENCES1 1 5; 2 2 6; 3 3 7; 4 4 8; 5 5 6; 6 7 8; 7 5 7; 8 6 8; 9 5 9; 10 6 10;11 7 11; 12 8 12; 13 9 10; 14 11 12; 15 9 11; 16 10 12; 17 13 14; 18 15 16;19 6 14; 20 8 16; 21 14 16; 22 14 17; 23 16 18; 24 10 17; 25 12 18; 26 17 18;27 19 20; 28 21 22; 29 20 22; 30 7 20; 31 8 22; 32 20 23; 33 22 24; 34 23 24;35 11 23; 36 12 24; 37 25 26; 38 22 26; 39 16 26; 40 26 27; 41 24 27; 42 18 27;START GROUP DEFINITIONMEMBERFLOOR_BEAMS 5 TO 8 13 TO 16 19 TO 21 24 TO 26 29 TO 31 34 TO 36 38 39 41 42END GROUP DEFINITIONDEFINE MATERIAL STARTISOTROPIC STEELE 2.05e+08POISSON 0.3DENSITY 78.5ALPHA 1.2e-05DAMP 0.03TYPE STEELSTRENGTH FY 253200 FU 407800 RY 1.5 RT 1.2ISOTROPIC CONCRETEE 2.17185e+07POISSON 0.17DENSITY 23.5616ALPHA 1e-05DAMP 0.05TYPE CONCRETESTRENGTH FCU 27579END DEFINE MATERIALMEMBER PROPERTY AMERICAN1 TO 4 9 TO 12 17 18 22 23 27 28 32 33 37 40 PRIS YD 0.5 ZD 0.55 TO 8 13 TO 16 19 TO 21 24 TO 26 29 TO 31 34 TO 36 38 39 41 -42 PRIS YD 0.5 ZD 0.5CONSTANTSMATERIAL CONCRETE ALLSUPPORTS1 TO 4 13 15 19 21 25 PINNEDMEMBER OFFSET5 TO 8 13 TO 16 19 TO 21 24 TO 26 29 TO 31 34 TO 36 38 39 41 -42 START LOCAL 0.25 0 05 TO 8 13 TO 16 19 TO 21 24 TO 26 29 TO 31 34 TO 36 38 39 41 -42 END LOCAL -0.25 0 0LOAD 1 LOADTYPE Dead TITLE DLSELFWEIGHT Y -1 FLOOR LOADYRANGE 0 8 FLOAD -3.75 GYPERFORM ANALYSISFINISH
Based on a preliminary investigation, it seems like deviations are being caused by the floor load when the offset is in there. I have forwarded this issue to our development desk for further investigation. Help Ticket# 555925 has been filed.
Ok.