Could someone please explain why the floor loads "disappear" after I added a two ton monorail. Please look at members 32 and 34 of the Ex Floor_Calc and members 32 33 34 of the Monorail_Calc STAAD documents attached.
EX Floor_Calc
STAAD SPACE START JOB INFORMATION ENGINEER DATE 06-Nov-09 JOB NAME 2 TON RECLAIM MONORAIL JOB CLIENT ENGINEER NAME CKM END JOB INFORMATION INPUT WIDTH 79 UNIT FEET KIP JOINT COORDINATES 1 0 0 0; 2 14 0 0; 3 0 0 14; 4 14 0 14; 5 0 0 28; 6 14 0 28; 11 0 16.33 0; 12 14 16.33 0; 13 0 16.33 14; 14 14 16.33 14; 15 0 16.33 28; 16 14 16.33 28; 17 2.625 16.33 0; 18 5.25 16.33 0; 19 8.75 16.33 0; 20 11.375 16.33 0; 22 2.625 16.33 14; 23 5.25 16.33 14; 24 7 16.33 14; 25 8.75 16.33 14; 26 11.375 16.33 14; 27 0 16.33 18.67; 29 7 16.33 18.67; 30 14 16.33 18.67; 31 0 16.33 23.34; 32 14 16.33 23.34; 41 0 29 0; 42 14 29 0; 43 0 29 14; 44 14 29 14; 45 0 29 28; 46 14 29 28; 51 7 8.17 28; MEMBER INCIDENCES 1 1 11; 2 11 41; 3 2 12; 4 12 42; 5 3 13; 6 13 43; 7 4 14; 8 14 44; 9 5 15; 10 15 45; 11 6 16; 12 16 46; 20 11 17; 21 17 18; 22 18 19; 23 19 20; 24 20 12; 25 13 22; 26 22 23; 27 23 24; 28 24 25; 29 25 26; 30 26 14; 32 27 29; 34 29 30; 35 31 32; 36 15 16; 40 11 13; 41 13 27; 42 27 31; 43 31 15; 44 17 22; 46 18 23; 47 24 29; 48 19 25; 49 20 26; 50 12 14; 51 14 30; 52 30 32; 53 32 16; 71 5 51; 72 51 16; 73 6 51; 74 51 15; START USER TABLE TABLE 1 UNIT INCHES KIP WIDE FLANGE W14X103 30.3 14.25 0.495 14.575 0.813 1170 420 6.02 7.05375 23.6989 W10X21 6.2 9.9 0.24 5.75 0.34 107 10.8 0.21 2.376 3.91 W8X17 5.01 8 0.23 5.25 0.308 56.6 7.44 0.147 1.84 3.234 END UNIT FEET KIP DEFINE MATERIAL START ISOTROPIC STEEL E 4.176e+006 POISSON 0.3 DENSITY 0.489024 ALPHA 6e-006 DAMP 0.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 9 TO 12 TABLE ST W8X31 5 6 TABLE ST W12X58 20 TO 30 TABLE ST W16X26 32 34 35 44 46 48 49 TABLE ST W8X13 71 TO 74 TABLE ST L30304 47 TABLE ST W6X15 7 8 TABLE ST W12X72 MEMBER PROPERTY AMERICAN 1 TO 4 UPTABLE 1 W14X103 41 TO 43 51 TO 53 UPTABLE 1 W10X21 36 40 50 UPTABLE 1 W8X17 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 TO 6 PINNED 41 TO 46 FIXED MEMBER RELEASE 40 44 46 48 50 BOTH MX MY MZ 20 25 36 41 47 51 71 73 START MX MY MZ 24 30 35 36 43 53 72 74 END MX MY MZ 32 35 49 START MX MY 34 47 49 END MX MY LOAD 1 SELFWEIGHT SELFWEIGHT Y -1 LOAD 2 DEAD LOAD (50 PSF) JOINT LOAD 17 20 FY -0.92 18 19 FY -0.46 27 30 TO 32 FY -1.63 LOAD 3 LIVE LOAD (125 PSF) SAME TRIB AREAS JOINT LOAD 17 20 FY -2.3 18 19 FY -1.16 *LIVE LOAD = 75 PSF ELEVATED PLATFORMS IBC 27 30 TO 32 FY -2.45 LOAD 4 BRACING LOAD FROM DWG W-71-313-6 *AND LOADS FROM 175 TON BINS MEMBER LOAD 72 CON X 11.4 10.75 JOINT LOAD 41 TO 44 FY -87.5 LOAD 5 LOADTYPE Dead TITLE LOAD CASE 7 FLOOR LOAD YRANGE 0 16.33 FLOAD -0.05 XRANGE 0 5.25 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.05 XRANGE 8.75 14 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.05 XRANGE 0 14 ZRANGE 14 28 GY LOAD 6 LOADTYPE Live TITLE LOAD CASE 8 FLOOR LOAD YRANGE 0 16.33 FLOAD -0.125 XRANGE 0 5.25 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.125 XRANGE 8.75 14 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.075 XRANGE 0 14 ZRANGE 14 28 GY LOAD 7 MR ULTIMATE LOAD MEMBER LOAD 32 CON GY -8.76 2.63 32 CON GZ -1.90 2.63 LOAD COMB 8 1.4D 1 1.4 2 1.4 4 1.0 5 1.4 LOAD COMB 9 1.2D + 1.6L + 1.07 1 1.2 2 1.2 5 1.4 3 1.6 4 1.0 6 1.6 7 1.0 PERFORM ANALYSIS LOAD LIST 8 9 PARAMETER 1 CODE LRFD *300/1.4 FOR SERVICE LOAD DFF 214 ALL *500/1.4 FOR SERVICE LOAD FOR MONORAIL DJ1 11 MEMB 20 TO 24 DJ2 12 MEMB 20 TO 24 DJ1 13 MEMB 25 TO 30 DJ2 14 MEMB 25 TO 30 DJ1 13 MEMB 41 TO 43 DJ2 15 MEMB 41 TO 43 DJ1 14 MEMB 51 TO 53 DJ2 16 MEMB 51 TO 53 DJ1 27 MEMB 32 34 DJ2 30 MEMB 32 34 UNT 1 MEMB 20 TO 30 32 34 TO 36 40 TO 44 46 TO 53 CHECK CODE ALL PRINT ANALYSIS RESULTS FINISH
Monorail_Calc
STAAD SPACE START JOB INFORMATION ENGINEER DATE 06-Nov-09 JOB NAME 2 TON RECLAIM MONORAIL JOB CLIENT ENGINEER NAME CKM END JOB INFORMATION INPUT WIDTH 79 UNIT FEET KIP JOINT COORDINATES 1 0 0 0; 2 14 0 0; 3 0 0 14; 4 14 0 14; 5 0 0 28; 6 14 0 28; 11 0 16.33 0; 12 14 16.33 0; 13 0 16.33 14; 14 14 16.33 14; 15 0 16.33 28; 16 14 16.33 28; 17 2.625 16.33 0; 18 5.25 16.33 0; 19 8.75 16.33 0; 20 11.375 16.33 0; 22 0 16.33 5.21; 23 2.625 16.33 5.21; 24 2.625 16.33 10.42; 25 2.625 16.33 14; 26 5.25 16.33 14; 27 7 16.33 14; 28 8.75 16.33 14; 29 11.375 16.33 14; 30 0 16.33 18.67; 31 2.625 16.33 18.67; 32 7 16.33 18.67; 33 14 16.33 18.67; 34 0 16.33 23.34; 35 14 16.33 23.34; 41 0 29 0; 42 14 29 0; 43 0 29 14; 44 14 29 14; 45 0 29 28; 46 14 29 28; 51 7 8.17 28; 101 2.625 12.42 10.42; 102 2.625 12.42 14; 103 2.625 12.42 18.67; MEMBER INCIDENCES 1 1 11; 2 11 41; 3 2 12; 4 12 42; 5 3 13; 6 13 43; 7 4 14; 8 14 44; 9 5 15; 10 15 45; 11 6 16; 12 16 46; 20 11 17; 21 17 18; 22 18 19; 23 19 20; 24 20 12; 25 13 25; 26 25 26; 27 26 27; 28 27 28; 29 28 29; 30 29 14; 32 30 31; 33 31 32; 34 32 33; 35 34 35; 36 15 16; 41 11 22; 42 22 13; 43 13 30; 44 30 34; 45 34 15; 46 17 23; 47 23 24; 48 24 25; 49 18 26; 50 27 32; 51 19 28; 52 20 29; 53 12 14; 54 14 33; 55 33 35; 56 35 16; 71 5 51; 72 51 16; 73 6 51; 74 51 15; 101 24 101; 102 25 102; 103 31 103; 104 22 23; 201 101 102; 202 102 103; START USER TABLE TABLE 1 UNIT INCHES KIP WIDE FLANGE W14X103 30.3 14.25 0.495 14.575 0.813 1170 420 6.02 7.05375 23.6989 W10X21 6.2 9.9 0.24 5.75 0.34 107 10.8 0.21 2.376 3.91 W8X17 5.01 8 0.23 5.25 0.308 56.6 7.44 0.147 1.84 3.234 END UNIT FEET KIP DEFINE MATERIAL START ISOTROPIC STEEL E 4.176e+006 POISSON 0.3 DENSITY 0.489024 ALPHA 6e-006 DAMP 0.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 9 TO 12 TABLE ST W8X31 5 6 TABLE ST W12X58 20 TO 30 TABLE ST W16X26 32 TO 35 46 TO 49 51 52 TABLE ST W8X13 71 TO 74 TABLE ST L30304 50 104 TABLE ST W6X15 7 8 TABLE ST W12X72 101 TO 103 TABLE ST W6X15 201 202 TABLE ST S12X31 MEMBER PROPERTY AMERICAN 1 TO 4 UPTABLE 1 W14X103 43 TO 45 54 TO 56 UPTABLE 1 W10X21 36 41 42 53 UPTABLE 1 W8X17 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 TO 6 PINNED 41 TO 46 FIXED MEMBER RELEASE 42 49 51 53 BOTH MX MY MZ 20 25 36 43 46 50 54 71 73 104 START MX MY MZ 24 30 35 36 45 48 56 72 74 104 END MX MY MZ 32 35 52 START MX MY 34 50 52 END MX MY *201 START MX *202 END MX *101 TO 103 START MY LOAD 1 SELFWEIGHT SELFWEIGHT Y -1 LOAD 2 DEAD LOAD (50 PSF) *TRIB AREA 4.67' MEMB 32 TO 35 *TRIB AREA 2.33' MEMB 25 TO 30 36 *TRIB AREA 2.63' MEMB 40 44 45 49 50 *TRIB AREA 1.32' MEMB 46 48 JOINT LOAD 17 20 FY -0.92 18 19 FY -0.46 30 33 TO 35 FY -1.63 LOAD 3 LIVE LOAD (125 PSF) SAME TRIB AREAS JOINT LOAD 17 20 FY -2.3 18 19 FY -1.16 *LIVE LOAD = 75 PSF ELEVATED PLATFORMS IBC 30 33 TO 35 FY -2.45 LOAD 4 BRACING LOAD FROM DWG W-71-313-6 *AND LOADS FROM 175 TON BINS MEMBER LOAD 72 CON X 11.4 10.75 JOINT LOAD 41 TO 44 FY -87.5 LOAD 5 DL MR SHEAR MEMBER LOAD 201 CON GY -0.63 0.25 201 CON GX 0.13 0.25 201 CON GZ 0.05 0.25 LOAD 6 LL MR SHEAR MEMBER LOAD 201 CON GY -5 0.25 201 CON GX 1 0.25 201 CON GZ 0.4 0.25 LOAD 7 DL MR MID MEMBER LOAD 202 CON GY -0.63 202 CON GX 0.13 202 CON GZ 0.05 LOAD 8 LL MR MID MEMBER LOAD 202 CON GY -5 202 CON GX 1 202 CON GZ 0.4 LOAD 9 DL MR OTHER SHEAR MEMBER LOAD 202 CON GY -0.63 4.5 202 CON GX 0.13 4.5 202 CON GZ 0.05 4.5 LOAD 10 LL MR OTHER SHEAR MEMBER LOAD 202 CON GY -5 4.5 202 CON GX 1 4.5 202 CON GZ 0.4 4.5 LOAD 11 LOADTYPE Dead TITLE LOAD CASE 7 FLOOR LOAD YRANGE 0 16.33 FLOAD -0.05 XRANGE 0 5.25 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.05 XRANGE 8.75 14 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.05 XRANGE 0 14 ZRANGE 14 28 GY LOAD 12 LOADTYPE Live TITLE LOAD CASE 8 FLOOR LOAD YRANGE 0 16.33 FLOAD -0.125 XRANGE 0 5.25 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.125 XRANGE 8.75 14 ZRANGE 0 14 GY YRANGE 0 16.33 FLOAD -0.075 XRANGE 0 7 ZRANGE 14 18.67 GY YRANGE 0 16.33 FLOAD -0.075 XRANGE 7 14 ZRANGE 14 18.67 GY YRANGE 0 16.33 FLOAD -0.075 XRANGE 0 14 ZRANGE 18.67 28 GY LOAD COMB 13 1.4D 1 1.4 2 1.4 4 1.0 11 1.4 LOAD COMB 14 1.2D + 1.6L MR SHEAR 1 1.2 2 1.2 3 1.6 4 1.0 11 1.2 5 1.2 6 1.6 12 1.6 LOAD COMB 15 1.2D + 1.6L MR MIDPOINT 1 1.2 2 1.2 3 1.6 4 1.0 11 1.2 7 1.2 8 1.6 12 1.6 LOAD COMB 16 1.2D + 1.6L MR OTHER SHEAR 1 1.2 2 1.2 3 1.6 4 1.0 11 1.2 9 1.2 10 1.6 12 1.6 PERFORM ANALYSIS LOAD LIST 13 TO 16 PARAMETER 1 CODE LRFD *300/1.4 FOR SERVICE LOAD DFF 214 MEMB 1 TO 12 20 TO 30 32 TO 36 41 TO 56 71 TO 74 101 TO 104 *500/1.4 FOR SERVICE LOAD FOR MONORAIL DFF 357 MEMB 201 202 DJ1 11 MEMB 20 TO 24 DJ2 12 MEMB 20 TO 24 DJ1 13 MEMB 25 TO 30 DJ2 14 MEMB 25 TO 30 DJ1 13 MEMB 43 TO 45 DJ2 15 MEMB 43 TO 45 DJ1 14 MEMB 54 TO 56 DJ2 16 MEMB 54 TO 56 DJ1 30 MEMB 32 TO 34 DJ2 33 MEMB 32 TO 34 DJ1 17 MEMB 46 TO 48 DJ2 25 MEMB 46 TO 48 DJ1 11 MEMB 41 42 DJ2 13 MEMB 41 42 UNT 1 MEMB 20 TO 30 32 TO 36 41 TO 56 CHECK CODE ALL PRINT ANALYSIS RESULTS FINISH
Thanks.
The Modeling mode is showing the graphic depiction of the FLOOR load in both versions of your model.
Are you able to see the load in Modeling mode? If not, it could be an issue of scale, which you can adjust in the Diagrams dialog.
Or are you describing an effect that you are seeing in analysis results?
Chris
I'm wondering about the effect that I see in the analysis results. I did a quick hand calc for a simple beam on the ex floor and came up with an internal moment that matched STAAD results. When I add the monorail, the internal moment goes down, not up as expected.
I'm not sure which load case you're referring to, so I picked the one that was named "LOAD CASE 8" in both models...just for clarity, that is LC 6 in EX Floor_Calc and it is LC 12 in Monorail_Calc.
In that load case, you see a reduction in the moment applied to beams 32 and 34 in EX Floor_Calc (beams 32, 33 and 34 in Monorail_Calc) because of the stiffening effect of the underslung monorail support beam (the S12x31). Since that two-span beam is modeled as continuous, it is resisting the tendency for beams 32, 33 and 34 to deflect downward.
If this doesn't quite address your concern, please let me know exactly which load conditions you're comparing between the two different models, and I'll study those for you.
I'd also like to offer you a general comment about defining ranges for FLOOR loads. It is generally good practice to define the ranges slightly outboard of the nodal coordinates that define the perimeter members. That was you minimize the potential for errors in the interpretation of your loads as a result of roundoff errors.
Cheers,
Thank you for explaining. Also thanks for the tip about the floor loads.
Any time!