Sir,
In my model (attached), one of the criteria of steel structure qualification is to check the deflection of the member
To check the deflection of structural member , I used the below command
1. Using the the command report - section displacement , I am checking the maximum displacement value .
Output shows 0.035 mm is the max. displacement in first row (red box) and below if i go i see the max. displacement is 0 but the corresponding global x displacement as 110.095 mm (indicated in green box)
Doubt is : How the global displacement is taken, whether the member see 110.095 mm displacement.
2. Is this approach to check the deflection of member is correct ? Any other method to check the deflection of member.
Kindly help
STAAD SPACE START JOB INFORMATION ENGINEER DATE 22-Jul-21 END JOB INFORMATION INPUT WIDTH 79 UNIT MMS NEWTON JOINT COORDINATES 1 0 0 0; 2 0 0 700; 3 0 0 750; 4 0 -500 700; 5 0 -600 700; MEMBER INCIDENCES 1 1 2; 2 2 3; 3 2 4; 4 4 5; DEFINE MATERIAL START ISOTROPIC STEEL E 205000 POISSON 0.3 DENSITY 7.68195e-005 ALPHA 1.2e-005 DAMP 0.03 TYPE STEEL STRENGTH FY 253.2 FU 407.8 RY 1.5 RT 1.2 END DEFINE MATERIAL MEMBER PROPERTY INDIAN 1 TO 4 TABLE FR ISMC150 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED LOAD 1 LOADTYPE Dead TITLE DL SELFWEIGHT Y -1 JOINT LOAD 4 FY -60 LOAD 2 LOADTYPE Live TITLE SL(OBE) JOINT LOAD 4 FZ 279 LOAD 4 LOADTYPE Live TITLE SL(OBE)WITH -VE JOINT LOAD 4 FZ -279 LOAD 6 LOADTYPE Seismic TITLE EQX(OBE) SELFWEIGHT X 1 SELFWEIGHT Y 1 SELFWEIGHT Z 1 JOINT LOAD 4 FX 279 4 FY 279 4 FZ 279 4 FX 60 4 FY 60 4 FZ 60 SPECTRUM SRSS X 0.5 ACC DAMP 0 LIN 20 721.4; 4 721.4; 2.85714 1003.7; 2.5 1097.1; 2.22222 1474.9; 2 1760.3; 1.66667 1911; 1.53846 1919.5; 1.42857 2539.4; 1.33333 2539.4; 1.17647 3318; 1.05263 3519.2; 1 4373.9; 0.952381 4373.9; 0.869565 4465.4; 0.833333 4827.1; 0.8 5699.7; 0.740741 5921.3; 0.689655 6899.2; 0.666667 7645; 0.645161 9421.3; 0.625 10451.8; 0.588235 11243.7; 0.555556 13601.4; 0.540541 15959.1; 0.487805 21846.8; 0.47619 29377.2; 0.454545 36907.7; 0.425532 59532.8; 0.416667 81805.9; 0.4 111269; 0.3125 111269; 0.30303 117660; 0.285714 160525; 0.28169 181958; 0.273973 203390; 0.20202 203390; 0.196078 198996; 0.192308 187639; 0.186916 153569; 0.183486 150204; 0.181818 138109; 0.178571 126015; 0.175439 105014; 0.173913 96107.3; 0.172414 90389.1; 0.169492 75347; 0.168067 69588.5; 0.166667 67355.3; 0.163934 61382.9; 0.16129 58370.6; 0.15873 53667.7; 0.15748 53009; 0.15625 52569.9; 0.153846 50153.1; 0.152672 49206.2; 0.151515 48782.1; 0.150376 48499.3; 0.148148 47818.7; 0.145985 46457.5; 0.143885 46910.8; 0.142857 47370; 0.140845 48438.1; 0.13986 51896.9; 0.138889 58767.7; 0.137931 61464.5; 0.136054 72402.6; 0.134228 82423.3; 0.133333 99365; 0.131579 116307; 0.12987 130149; 0.129032 133632; 0.128205 140598; 0.127389 143009; 0.125786 143357; 0.0930233 143357; 0.0925926 140214; 0.0921659 137146; 0.0913242 134079; 0.0909091 131011; 0.0896861 119027; 0.0888889 116532; 0.0881057 115284; 0.0877193 114036; 0.0873362 112861; 0.0865801 109291; 0.0858369 98942.2; 0.0854701 97936.6; 0.0847458 96930.9; 0.0823045 96930.9; 0.0809717 90325.2; 0.0806452 72211.9; 0.08 70545.6; 0.0796813 68879.3; 0.0793651 66321.1; 0.0787402 63341.7; 0.078125 60730.7; 0.0775194 58727.5; 0.0772201 56724.3; 0.0766283 52583.1; 0.0760456 49364.3; 0.0754717 47754.9; 0.0740741 44769; 0.0738007 42862.5; 0.0732601 40956; 0.0727273 39310.5; 0.0724638 38542.2; 0.0719424 37823.6; 0.0716846 37620; 0.0711744 37416.5; 0.0704225 37029.6; 0.0701754 36482.3; 0.0696864 36286.9; 0.0692042 36189.3; 0.0687285 35993.9; 0.0682594 34260.4; 0.0680272 34074.1; 0.0675676 33887.7; 0.0657895 33636.8; 0.0649351 32886.6; 0.0645161 32387.9; 0.0641026 32138.5; 0.0634921 31640.1; 0.0630915 31385.2; 0.0626959 31257.8; 0.0591716 30645.8; 0.0588235 29853; 0.0584795 29456.6; 0.0554017 29014.8; 0.0550964 28695.6; 0.0547945 28536.1; 0.0546448 28376.5; 0.0526316 28140.1; 0.0522193 27528.5; 0.0508906 27407.5; 0.0507614 27197.5; 0.050505 26987.6; 0.0503778 26777.6; 0.0496278 26692.7; 0.0492611 26512.2; 0.0465116 26434.4; 0.0462963 26273.8; 0.0460829 26193.6; 0.0458716 26033; 0.0433839 25779.4; 0.04329 25728.1; 0.030303 24327.7; LOAD 7 LOADTYPE Seismic TITLE EQY(OBE) SPECTRUM SRSS Y 0.33 ACC DAMP 0 LIN 20 434.4; 4 434.4; 2.5 659.4; 2.22222 837.3; 2 943.4; 1.53846 1059.2; 1.42857 1258.7; 1.33333 1258.7; 1.17647 1428.4; 1 1585.9; 0.869565 1585.9; 0.740741 1812.4; 0.689655 1820.2; 0.666667 2000.1; 0.645161 2200.2; 0.625 2220.3; 0.606061 2220.3; 0.571429 2239.5; 0.555556 2356.5; 0.540541 2590.4; 0.487805 3348.7; 0.47619 3809.9; 0.454545 4271.1; 0.425532 5326.3; 0.416667 6543.3; 0.4 8273.9; 0.384615 8273.9; 0.37037 8938; 0.344828 11692.7; 0.338983 12566; 0.333333 12750.6; 0.289855 12750.6; 0.28169 12949.2; 0.273973 13593.8; 0.263158 16486.3; 0.25974 17046.9; 0.253165 17607.4; 0.246914 21876.6; 0.243902 22974; 0.238095 24071.5; 0.232558 24928; 0.227273 25705.1; 0.212766 25705.1; 0.208333 26000.8; 0.206186 27334.9; 0.204082 28862.1; 0.20202 31766.3; 0.19802 34520.2; 0.192308 42125.6; 0.190476 42890.7; 0.188679 43273.3; 0.138889 43273.3; 0.136986 40159.9; 0.136054 38463.7; 0.135135 37018.7; 0.130719 36274.1; 0.12987 38945.8; 0.129032 39756; 0.128205 41376.5; 0.127389 42390.8; 0.125786 43502.1; 0.125 43805.8; 0.0925926 43805.8; 0.0913242 43552.8; 0.0909091 43426.3; 0.0900901 41839; 0.0896861 41104.1; 0.0892857 40956.9; 0.0888889 40858.7; 0.0809717 40858.7; 0.0806452 38642.3; 0.08 37386.5; 0.0793651 35161.7; 0.0790514 34192.8; 0.0787402 33993.3; 0.078125 33051.6; 0.077821 32609.1; 0.0775194 32223.3; 0.0772201 31451.6; 0.0766283 29175.6; 0.0763359 28120.3; 0.0760456 27230.1; 0.0757576 26467.2; 0.0740741 23408.1; 0.0735294 21606; 0.0732601 21005.3; 0.0722022 18454.7; 0.0719424 18102.2; 0.0716846 17794.1; 0.0714286 17574.5; 0.0711744 17448.4; 0.070922 17352.8; 0.0706714 17318.1; 0.0701754 17294.7; 0.0696864 17190.6; 0.0692042 17138.5; 0.0687285 17034.4; 0.0682594 16187.4; 0.0680272 16101.6; 0.0657895 15794.1; 0.0649351 14489.2; 0.0647249 14212.5; 0.0645161 14001.8; 0.0643087 13822.7; 0.0630915 13216.9; 0.0628931 13149.3; 0.0623053 13098.7; 0.0591716 13098.7; 0.0588235 12663.6; 0.0584795 12446; 0.0576369 11742.2; 0.0574713 11640; 0.0571429 11537.9; 0.0568182 11333.6; 0.056338 11148.1; 0.0560224 11086.2; 0.0554017 10838.8; 0.0550964 10166.8; 0.0547945 9830.7; 0.0546448 9494.7; 0.0526316 9266.6; 0.0522193 9090.2; 0.0508906 9075.2; 0.0507614 8764.8; 0.050505 8454.3; 0.0503778 8143.9; 0.0498753 7918.1; 0.0496278 7861.7; 0.0493827 7666.4; 0.04914 7582; 0.0486618 7582; 0.0465116 7463.7; 0.0462963 7240.1; 0.0460829 7128.3; 0.0458716 6904.7; 0.0433839 6687.7; 0.04329 6651; 0.030303 5921.8; LOAD 8 LOADTYPE Seismic TITLE EQZ(OBE) SPECTRUM SRSS Z 0.5 ACC DAMP 0 LIN 20 716; 4 716; 2.85714 915.5; 2.5 1045.8; 2.22222 1361.4; 2 1610.5; 1.66667 1705.2; 1.53846 1861.5; 1.42857 2190; 1.25 2314.5; 1.17647 2887.1; 1.05263 3160.1; 1 3353.1; 0.952381 3353.1; 0.869565 3361; 0.833333 3690.2; 0.8 4392.1; 0.769231 4392.1; 0.714286 5047; 0.689655 5721.5; 0.666667 6082.6; 0.645161 7178.1; 0.625 7912.4; 0.588235 7935.1; 0.555556 9697.3; 0.540541 11459.4; 0.487805 14883; 0.47619 19192.4; 0.454545 23501.8; 0.425532 30841.7; 0.416667 38438.9; 0.4 48739.7; 0.384615 48739.7; 0.37037 58210; 0.344828 80230.5; 0.338983 90489.5; 0.333333 95243.4; 0.240964 95329.3; 0.238095 97530; 0.175439 97530; 0.172414 92666.2; 0.169492 87029.4; 0.168067 84863.4; 0.166667 84002; 0.165289 82279.2; 0.16129 75098.8; 0.15873 66346.5; 0.15748 64887.9; 0.15625 63915.4; 0.153846 59435.9; 0.152672 57705.2; 0.151515 56992.7; 0.150376 56517.7; 0.138889 56517.7; 0.136986 51060.1; 0.136054 48579.4; 0.135135 46594.7; 0.134228 44766.5; 0.133333 43251.2; 0.13245 42361.7; 0.131579 41546.5; 0.130719 40880; 0.12987 40435.7; 0.129032 38447.4; 0.127389 36297.6; 0.126582 36136; 0.125786 36047.9; 0.125 35989.2; 0.10929 35989.2; 0.108108 34221.8; 0.107527 33415.1; 0.106952 32762.5; 0.105263 29895.1; 0.104712 28971; 0.104167 28093.2; 0.103627 27305.5; 0.103093 26669.6; 0.102564 26280.3; 0.101523 26266.2; 0.0943396 26266.2; 0.0930233 25298.9; 0.0925926 25017; 0.0921659 24822.3; 0.0917431 24733.6; 0.0909091 24714.3; 0.0873362 24714.3; 0.0865801 24291; 0.0862069 24100.6; 0.0858369 23952.4; 0.0854701 23853.7; 0.0823045 23853.7; 0.0809717 22664; 0.0803213 20008.6; 0.08 19810.2; 0.0796813 19413.3; 0.0790514 17906.4; 0.0787402 17276.5; 0.0784314 16893.7; 0.078125 16574.7; 0.077821 16329.1; 0.0775194 16122.8; 0.0766283 15321.8; 0.0760456 15244.7; 0.0687285 15244.7; 0.0682594 15007.9; 0.0677966 14691; 0.0675676 14598.9; 0.0673401 14527; 0.0657895 14337.5; 0.0643087 13530.7; 0.0641026 13459; 0.0632911 13110.6; 0.0630915 13070.2; 0.0625 13036.2; 0.0591716 13036.2; 0.0552486 12566.9; 0.0526316 12566.9; 0.0508906 12512.9; 0.0506329 12355.6; 0.0502513 12296.9; 0.0465116 12296.9; 0.0440529 11932.5; 0.04329 11932.5; 0.030303 11661.8; LOAD COMB 12 LC1(OBE) 1 1.0 2 1.0 6 1.0 LOAD COMB 13 LC2(OBE) 1 1.0 2 1.0 7 1.0 LOAD COMB 14 LC3(OBE) 1 1.0 2 1.0 8 1.0 LOAD COMB SRSS 15 LC4(OBE) -1 1.0 -2 1.0 6 1.0 7 1.0 8 1.0 1 LOAD COMB 16 LC1(OBE WITH -VE SL) 1 1.0 4 1.0 6 1.0 LOAD COMB 17 LC2(OBE WITH -VE SL) 1 1.0 4 1.0 7 1.0 LOAD COMB 18 LC3(OBE WITH -VE SL) 1 1.0 4 1.0 8 1.0 LOAD COMB SRSS 19 LC4(OBE WITH -VE SL) -1 1.0 6 1.0 7 1.0 8 1.0 -4 1.0 1 PERFORM ANALYSIS PRINT STATICS CHECK FINISH FINISH
Can some one pls clarify
If your question is on the Indian steel code, see this
https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/28290/serviceability-check-in-design-according-to-is800-2007
For the AISC code, see this
https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/20793/strength-serviceability-check-in-design
Sir,Thank you for the clarification. But my requirement is different.
Model has a built-up box section ( ISMC 150 box) and is not supported for design check since I have not made in section wizard option.Hence used the command report - section displacement. (doubt on that is indicated in point no.1)I require to check the members deflection manually. Kindly help
The section displacement is measured relative to the deflected position of the 2 ends of the member.
Joint displacement is the deflection measured from the undeflected position of the structure.
To obtain the global displacement of the intermediate section locations, an approximate way is to add the average of the joint displacements of the member's start and end nodes to the intermediate point's section displacement. An exact way to obtain it is to split the beam into segments so that a node is created at the point where you wish to obtain the deflection, and then look at the joint displacement of that node.
Normally, deflection checks done during the steel design stage use the section displacements. Joint displacements are used to check the drift of the building.
However, if the structure has cantilever portions, the deflection check of cantilever members should be based on the difference in joint deflection (global displacement) of the 2 ends. This is what STAAD does if you use the CAN parameter for deflection check during steel design.
thank you sir
k sir.
In the attached the table, highlighted in green max. disp. is 0 mm but the global displacement is 110mm.
What it implies. How this global displacement is calculated.