Hi,
I am performing analysis of steel structure using Eurocode.
I have specified same load in all 3 directions as inertial load for seismic analysis.
But still i am getting Warning :
*** Note: ALL MASS RELATED WARNINGS, IF ANY, WILL BE WRITTEN IN _MASSEURO.TXT FILE.
*** WARNING *** DYNAMIC MASSES IN GLOBAL X, Y AND Z DIRECTIONS ARE NOT SAME.
WARNING MESSAGES ARE WRITTEN IN _MASSEURO.TXT FILE.
and also mass participation factor are distributed in different modes for same direction, i mean no mode is dominating with good mass participation.
Not even more than 60% in any single mode for particular direction.
Why is it so? Is my procedure wrong?
I have attached screen shot of o/p file for participation factor
My i/p file is :
INPUT WIDTH 79
UNIT MMS KG
JOINT COORDINATES
1 0 0 0; 2 2175 0 0; 3 2175 0 -1635; 4 0 0 -1635; 5 0 855 0; 6 2175 855 0;
7 2175 855 -1635; 8 0 855 -1635; 9 0 2465 0; 10 2175 2465 0;
11 2175 2465 -1635; 12 0 2465 -1635; 13 0 5000 0; 14 2175 5000 0;
15 2175 5000 -1635; 16 0 5000 -1635; 17 0 855 -487.5; 18 2175 855 -487.5;
19 895.5 855 -487.5; 20 1270.5 855 -487.5; 21 1363.5 855 -487.5;
22 1622.5 855 -487.5; 23 895.5 1155 -487.5; 24 1270.5 1155 -487.5;
25 1363.5 1155 -487.5; 26 1622.5 1155 -487.5; 27 895.5 1155 -244.5;
28 1270.5 1155 -244.5; 29 1363.5 1155 -256.5; 30 1622.5 1155 -256.5;
31 2175 855 -892.5; 32 2175 1655 -892.5; 33 1958.5 1655 -892.5;
34 2175 855 -1254.5; 35 2175 1655 -1254.5; 36 1958.5 1655 -1254.5;
37 0 2465 -487.5; 38 2175 2465 -487.5; 39 0 2465 -1062.5; 40 2175 2465 -1062.5;
41 1827.5 2465 -487.5; 42 1827.5 1916 -487.5; 43 1827.5 1916 -287.5;
44 2175 1916 0; 45 2175 1916 -408.5;
MEMBER INCIDENCES
1 1 5; 2 5 9; 3 9 13; 4 2 6; 5 6 44; 6 10 14; 7 3 7; 8 7 11; 9 11 15; 10 4 8;
11 8 12; 12 12 16; 13 5 17; 14 17 8; 15 8 7; 16 7 34; 17 18 6; 18 17 19;
19 9 10; 20 10 38; 21 11 12; 22 9 37; 23 13 14; 24 14 15; 25 15 16; 26 13 16;
27 19 20; 28 20 21; 29 21 22; 30 22 18; 31 19 23; 32 23 27; 33 20 24; 34 24 28;
35 21 25; 36 25 29; 37 22 26; 38 26 30; 39 31 18; 40 31 32; 41 32 33; 42 34 31;
43 34 35; 44 35 36; 45 37 39; 46 38 40; 47 37 41; 48 39 12; 49 40 11; 50 39 40;
51 41 38; 52 41 42; 53 42 43; 54 44 10; 55 44 45;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 20904.2
POISSON 0.3
DENSITY 7.83341e-006
ALPHA 1.2e-005
DAMP 0.03
TYPE STEEL
STRENGTH FY 25.8192 FU 41.584 RY 1.5 RT 1.2
END DEFINE MATERIAL
MEMBER PROPERTY INDIAN
13 TO 18 27 TO 44 52 53 TABLE ST ISMC100
1 TO 12 19 TO 22 45 TO 51 54 55 TABLE ST ISMC125
23 TO 26 TABLE ST ISMC75
CONSTANTS
BETA 90 MEMB 31 33 35 37 52
MATERIAL STEEL ALL
SUPPORTS
1 TO 4 FIXED
CUT OFF MODE SHAPE 24
LOAD 1 LOADTYPE Seismic TITLE EARTHQUAKE IN X DIRECTION
SELFWEIGHT X 1
SELFWEIGHT Y 1
SELFWEIGHT Z 1
FLOOR LOAD
*Dead load of gratings for seismic action
YRANGE 2465 2465 FLOAD 4.1e-005 GX
YRANGE 2465 2465 FLOAD 4.1e-005 GY
YRANGE 2465 2465 FLOAD 4.1e-005 GZ
*Live load for seismic action= (live load*0.8)
YRANGE 2465 2465 FLOAD 0.0002 GX
YRANGE 2465 2465 FLOAD 0.0002 GY
YRANGE 2465 2465 FLOAD 0.0002 GZ
*Dead load of railling for seismic action
MEMBER LOAD
19 TO 22 45 46 48 49 UNI GX -0.015
19 TO 22 45 46 48 49 UNI GY -0.015
19 TO 22 45 46 48 49 UNI GZ -0.015
*Equipment loads for seismic action
MEMBER LOAD
32 34 CON GX -30 193
36 38 CON GX -20 193
41 44 CON GX -40 166.5
47 50 CON GX -160 1083.5
55 CON GX -126 348.5
53 CON GX -126 140
47 50 CON GX -450 482.5
32 34 CON GY -30 193
36 38 CON GY -20 193
41 44 CON GY -40 166.5
47 50 CON GY -160 1083.5
55 CON GY -126 348.5
53 CON GY -126 140
47 50 CON GY -450 482.5
32 34 CON GZ -30 193
36 38 CON GZ -20 193
41 44 CON GZ -40 166.5
47 50 CON GZ -160 1083.5
55 CON GZ -126 348.5
53 CON GZ -126 140
47 50 CON GZ -450 482.5
SPECTRUM CQC EURO 2004 ELASTIC RS2 X 1 ACC DAMP 0.05 LIN
SOIL TYPE C ALPHA 0.1 Q 1
LOAD 2 LOADTYPE Seismic TITLE EARTHQUAKE IN Z DIRECTION
SPECTRUM CQC EURO 2004 ELASTIC RS2 Z 1 ACC DAMP 0.05 LIN
SOIL TYPE C ALPHA 0.1 Q 1
LOAD 3 LOADTYPE Dead TITLE SELFWEIGHT, RAILING & GRATING WEIGHT
SELFWEIGHT Y -1
FLOOR LOAD
YRANGE 2465 2465 FLOAD -4.1e-005 GY
MEMBER LOAD
19 TO 22 45 46 48 49 UNI GY -0.015
LOAD 4 LOADTYPE Live TITLE IMPOSED FLOOR LOAD
FLOOR LOAD
YRANGE 2465 2465 FLOAD -0.0002 GY
LOAD 5 LOADTYPE Dead TITLE EQUIPMENT LOAD
MEMBER LOAD
32 34 CON GY -30 193
36 38 CON GY -20 193
41 44 CON GY -40 166.5
47 50 CON GY -160 1083.5
55 CON GY -126 348.5
53 CON GY -126 140
47 50 CON GY -450 482.5
*load case 5 partial safety factor is multiplied by 1.2 to consider piping weight in each combination
*ULS:
*EQU condition
LOAD COMB 6 ULS:EQU CONDITION CASE 1
3 1.1 5 1.08 4 1.5
LOAD COMB 7 ULS:EQU CONDITION CASE 2
3 0.9 5 1.32 4 1.5
*STR/GEO condition)
LOAD COMB 8 ULS: STR/GEO CONDITION CASE 1
3 1.35 5 1.2 4 1.5
LOAD COMB 9 ULS: STR/GEO CONDITION CASE 2
5 1.62 3 1.0 4 1.5
*Frequent combination check for SLS
LOAD COMB 10 SLS: FREQUENT COMBINATION CASE 1
3 1.0 5 1.2 4 0.9
LOAD COMB 11 SLS: FREQUENT COMBINATION CASE 2
3 1.0 5 1.2 4 0.8
*seismic design condition
LOAD COMB 12 SEISMIC DESIGN COMBINATION CASE 1
3 1.0 5 1.2 1 1.0 2 0.3 4 0.8
LOAD COMB 13 SEISMIC DESIGN COMBINATION CASE 2
3 1.0 5 1.2 2 1.0 1 0.3 4 0.8
PERFORM ANALYSIS PRINT STATICS CHECK
PARAMETER 1
CODE EN 1993-1-1:2005
ALPHA 1 ALL
BEAM 3 ALL
BETA 1 ALL
C1 0.712 MEMB 13 TO 30 32 34 36 38 39 41 42 44 TO 51 53 55
C2 0.652 MEMB 13 TO 30 32 34 36 38 39 41 42 44 TO 51 53 55
C3 1.07 MEMB 13 TO 30 32 34 36 38 39 41 42 44 TO 51 53 55
CAN 1 MEMB 55
CMM 2 MEMB 19 TO 22 45 TO 51
CMM 4 MEMB 19 47 50
CMN 0.5 MEMB 13 TO 30 39 42 45 TO 51
CMN 0.7 MEMB 1 TO 12 31 TO 38 40 41 43 44 52 TO 55
DFF 325 ALL
ELB 0 ALL
FAB 3 ALL
GM0 1 ALL
GM1 1 ALL
GM2 1.25 ALL
KC 0.9 MEMB 13 TO 30 32 34 36 38 39 41 42 44 TO 51 53 55
KY 1 MEMB 1 TO 12 31 33 35 37 40 43 52 54
KZ 1 MEMB 1 TO 12 31 33 35 37 40 43 52 54
LY 2175 MEMB 15 18 19 21 23 25 27 TO 30 47 50 51
LZ 2175 MEMB 15 18 19 21 23 25 27 TO 30 47 50 51
LY 1635 MEMB 13 14 16 17 20 22 24 26 39 42 45 46 48 49
LZ 1635 MEMB 13 14 16 17 20 22 24 26 39 42 45 46 48 49
MTH 0 ALL
PY 25.48 ALL
RATIO 1 ALL
SBLT 0 ALL
TRACK 4 ALL
ZG 37.5 MEMB 23 TO 26
ZG 50 MEMB 13 TO 18 27 TO 44 50 52 53 55
ZG 62.5 MEMB 1 TO 12 19 TO 22 45 TO 49 51 54
CHECK CODE ALL
PARAMETER 2
CODE EN 1993-1-1:2005
STEEL MEMBER TAKE OFF ALL
FINISH