Hi,
I several question regarding STAAD. My example model is attached below.1. I expect that the Mode 1 and Mode 2 will be pure translation in X and Z since my building and the load was symmetric. But, I got Mode 1 and 2 is not pure translation. Is there some mistake in my model? 2. I think my building is not rigid enough so that I apply rigid diaphragm to make the building more rigid and also increasing my column size. Still Mode 1 and 2 is not pure translation. Did I make a mistake while assigning the rigid diaphragm?3. How to determine the center of mass if I choose "calculating" in the diaphragm definition?4. In respond spectrum definition, what is the function of the "fill box" beside X Y X ?Thank you in advance.Regards,Charismawelly
STAAD SPACESTART JOB INFORMATIONENGINEER DATE 18-Sep-18END JOB INFORMATIONINPUT WIDTH 79UNIT METER KNJOINT COORDINATES1 0 0 0; 2 0 4 0; 3 4 4 0; 4 4 0 0; 5 0 0 4; 6 0 4 4; 7 4 4 4; 8 4 0 4;9 0 0 8; 10 0 4 8; 11 4 4 8; 12 4 0 8; 13 8 4 0; 14 8 0 0; 15 8 4 4; 16 8 0 4;17 8 4 8; 18 8 0 8; 19 0 8 0; 20 4 8 0; 21 0 8 4; 22 4 8 4; 23 0 8 8; 24 4 8 8;25 8 8 0; 26 8 8 4; 27 8 8 8; 28 0 12 0; 29 4 12 0; 30 0 12 4; 31 4 12 4;32 0 12 8; 33 4 12 8; 34 8 12 0; 35 8 12 4; 36 8 12 8;MEMBER INCIDENCES1 1 2; 2 4 3; 3 2 3; 4 2 6; 5 3 7; 6 5 6; 7 8 7; 8 6 7; 9 6 10; 10 7 11;11 9 10; 12 12 11; 13 10 11; 14 14 13; 15 3 13; 16 13 15; 17 16 15; 18 7 15;19 15 17; 20 18 17; 21 11 17; 26 2 19; 27 3 20; 28 19 20; 29 19 21; 30 20 22;31 6 21; 32 7 22; 33 21 22; 34 21 23; 35 22 24; 36 10 23; 37 11 24; 38 23 24;39 13 25; 40 20 25; 41 25 26; 42 15 26; 43 22 26; 44 26 27; 45 17 27; 46 24 27;47 19 28; 48 20 29; 49 28 29; 50 28 30; 51 29 31; 52 21 30; 53 22 31; 54 30 31;55 30 32; 56 31 33; 57 23 32; 58 24 33; 59 32 33; 60 25 34; 61 29 34; 62 34 35;63 26 35; 64 31 35; 65 35 36; 66 27 36; 67 33 36;ELEMENT INCIDENCES SHELL22 2 6 7 3; 23 6 10 11 7; 24 3 7 15 13; 25 7 11 17 15; 68 19 21 22 20;69 21 23 24 22; 70 20 22 26 25; 71 22 24 27 26; 72 28 30 31 29; 73 30 32 33 31;74 29 31 35 34; 75 31 33 36 35;ELEMENT PROPERTY22 TO 25 68 TO 75 THICKNESS 0.15DEFINE MATERIAL STARTISOTROPIC CONCRETEE 2.17185e+007POISSON 0.17DENSITY 23.5616ALPHA 1e-005DAMP 0.05TYPE CONCRETESTRENGTH FCU 27579END DEFINE MATERIALMEMBER PROPERTY1 2 6 7 11 12 14 17 20 26 27 31 32 36 37 39 42 45 47 48 52 53 57 58 60 63 -66 PRIS YD 0.4 ZD 0.43 TO 5 8 TO 10 13 15 16 18 19 21 28 TO 30 33 TO 35 38 40 41 43 44 46 -49 TO 51 54 TO 56 59 61 62 64 65 67 PRIS YD 0.4 ZD 0.2CONSTANTSMATERIAL CONCRETE ALLSUPPORTS1 4 5 8 9 12 14 16 18 FIXEDFLOOR DIAPHRAGMDIA 1 TYPE RIG HEI 4 MASTER 7DIA 2 TYPE RIG HEI 8 MASTER 22DIA 3 TYPE RIG HEI 12 MASTER 31LOAD 1 LOADTYPE Dead TITLE DEADSELFWEIGHT Y -1 ELEMENT LOAD22 TO 25 68 TO 75 PR GY -1.5LOAD 2 LOADTYPE Live TITLE LIVEELEMENT LOAD22 TO 25 68 TO 75 PR GY -2.5LOAD 3 LOADTYPE None TITLE MODALSELFWEIGHT X 1 SELFWEIGHT Z 1 SELFWEIGHT Y 1 ELEMENT LOAD22 TO 25 68 TO 75 PR GX 1.522 TO 25 68 TO 75 PR GZ 1.522 TO 25 68 TO 75 PR GY 1.522 TO 25 68 TO 75 PR GX 2.522 TO 25 68 TO 75 PR GZ 2.522 TO 25 68 TO 75 PR GY 2.5MODAL CALCULATION REQUESTEDLOAD 4 LOADTYPE None TITLE SEISMICXSELFWEIGHT X 1 SELFWEIGHT Z 1 SELFWEIGHT Y 1 ELEMENT LOAD22 TO 25 68 TO 75 PR GX 1.522 TO 25 68 TO 75 PR GZ 1.522 TO 25 68 TO 75 PR GY 1.522 TO 25 68 TO 75 PR GX 2.522 TO 25 68 TO 75 PR GZ 2.522 TO 25 68 TO 75 PR GY 2.5SPECTRUM CQC X 1 ACC SCALE 9.806 DAMP 0.05 LIN0 0.211; 0.183 0.528; 0.915 0.528; 0.965 0.476; 1.015 0.433; 1.115 0.397;1.215 0.367; 1.315 0.341; 1.415 0.319; 1.515 0.299; 1.615 0.281; 1.715 0.266;1.815 0.252; 1.915 0.24; 2.015 0.228; 2.115 0.218; 2.215 0.208; 2.315 0.2;2.415 0.192; 2.515 0.185; 2.615 0.178; 2.715 0.171; 2.815 0.166; 2.915 0.16;3.015 0.155; 3.115 0.15; 3.215 0.146; 3.315 0.141; 3.415 0.137; 3.515 0.134;3.615 0.13; 3.715 0.127; 3.815 0.123; 4 0.121;LOAD 5 LOADTYPE None TITLE SEISMICZSPECTRUM CQC Z 1 ACC SCALE 9.806 DAMP 0.05 LIN0 0.211; 0.183 0.528; 0.915 0.528; 0.965 0.476; 1.015 0.433; 1.115 0.397;1.215 0.367; 1.315 0.341; 1.415 0.319; 1.515 0.299; 1.615 0.281; 1.715 0.266;1.815 0.252; 1.915 0.24; 2.015 0.228; 2.115 0.218; 2.215 0.208; 2.315 0.2;2.415 0.192; 2.515 0.185; 2.615 0.178; 2.715 0.171; 2.815 0.166; 2.915 0.16;3.015 0.155; 3.115 0.15; 3.215 0.146; 3.315 0.141; 3.415 0.137; 3.515 0.134;3.615 0.13; 3.715 0.127; 3.815 0.123; 4 0.121;LOAD 6 LOADTYPE Mass TITLE MASSSELFWEIGHT Y -1 LIST ALLPERFORM ANALYSISFINISH