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When performing a wind and weight analysis on truss all memebrs pass; while performing a seismic analysis on a 6x12 m2 truss with 4.6m height (excentricity of 0.05, base shear coefficiente C=0.18, and elevation coefficient K=1) all members on the heels and piers don't pass the analysis. Tried redoing the same model based on some YouTube tutorials but same results (also tried assigning directly end length offsets, and defining the insertion point)

Hi everyone!, I'm trying to design a shed of truss span 85', I have experimented with many different types of trusses. A problem that is common among most of them is failure of member near eaves. Does anyone know how to solve this issue? (*Eaves height is 24' and I can't put any member to support truss.)

hi guys hope you all are fine , coming to the point , i have been modelling trusses for a factory building in ETABS 19 ,details of which are attached , span= 90 feet , dist b/w two adjacent trusses is 18 ' horizontal /vertical chords =2L 2.5"x2.5"x3/8" (double angle) Top chord w-sec 6x8.5 bottom chord w-section =6x20 CGI sheet with 20 psf load on top. 1) the middle portion of the bottom chord is failing i dont know the reason for that ? i have released the moment for each and every joint in the trusses , 2) should the top chord and bottom chord be 1 member or divided at each intersection with the h/v chords ?? 3) the behaviour of the truss is not ok at the mid section , as it should be tension rather than compression , thanks very much in advance , cheers

Hi, I am currently modelling a stress roof truss on ETABs, the truss has an overhang. I am having trouble modelling it as I keep getting this message: Load Case : Solving Linear Stiffness from Zero (unstressed) initial conditions THE STRUCTURE IS UNSTABLE OR ILL-CONDITIONED !!. CHECK THE STRUCTURE CAREFULLY FOR. TO OBTAIN FURTHER INFORMATION:. - USE THE STANDARD SOLVER, OR. - RUN AN EIGEN ANALYSIS USING AUTO FREQUENCY SHIFTING (WITH. ADDITIONAL MASS IF NEEDED) AND INVESTIGATE THE MODE SHAPES Can anyone help with this? I have attached screenshot of the roof truss. Thank you in advance,

Can any one please help me with resources they have for designing Steel roof truss and Rcc column joint? Also if there is any references available for modelling such structural joints in ETABS? Thanks

I have modelled a RCC building with a steel roof truss atop. Now when I run analysis, the reinfforcement in columns etabs shows is always the minimum reinforcement required. I cannot figure out why this is happening. Could anyone help me? Also, I remodeled it another time with all of steel components removed. The analysis result was satisfactory then. Why cant I get similar result with truss atop?

Hello Sir, I was trying to design a steel truss (layout attached). During design I found below comments in output text file: "THE STRUCTURE IS UNSTABLE OR ILL-CONDITIONED" I tried in two ways : Only truss was modeled (simple grid not actual layout) to find out the reason of ill conditions. Deformation behavior was normal but still it was showing unstable (modeled attached) Designed with column, no changes. Deformation shape was not proper (I used purlin in crest & eave ridge only as vetting org. suggested me not to use purlin except those) Can you guide me with following issues: What mistakes I have done in my FEM What is the actual process of modeling truss with steel/rcc column in etabs because every time I tried, deformation shape is not up to the mark. (to my knowledge, I have provided input as per suggestion given in etabs/csi manual) site layout plan_modified.dwg ONLY TRUSS_WITH COLUMN_LINEAR.EDB truss 8 ft.EDB ONLY TRUSS_WITH COLUMN_LINEAR.e2k

Salaam everyone! I wrote these scripts a few years back when i was working on my final year project. Definitely spent a lot of time & effort. I remember searching for any hints when i was about to embark on this project... This code may however be most useful for students & any pedagogic purposes while its application in real scenarios can't be denied either! My Project.zip

I am designing a skybridge connecting two buildings at 20m above ground. Bridge length is 22m. The Bridge is double storied. One Supporting end will be hinge support and another roller ( as there will be expansion gap). Does anyone have similar type of experience.. ??

Hi All, The following website has number of free civil engineering software and design sheets. Softwares Continuous beam analyzer -> https://sites.google.com/site/samsoninfinite/home/beam-analyzer 2D Truss Analyzer -> https://sites.google.com/site/samsoninfinite/home/plane-truss-analyzer 2D Frame Analyzer -> https://sites.google.com/site/samsoninfinite/home/plane-frame-analyzer Plane Stress Analyzer -> https://sites.google.com/site/samsoninfinite/home/plane-stress-analyzer 3D Truss and 3D Frame analyzer under development Design Sheets Beam Design ACI code -> https://sites.google.com/site/samsoninfinite/design-spreadsheets/rc-beam-aci-code-design-concrete Steel girder Offshore structure design -> https://sites.google.com/site/samsoninfinite/design-spreadsheets/t-girder-design-steel This website is constantly updated. Regards Zap Bran

I have been given an assignment to design a cantilever steel truss bridge of 35 meter span. I have analyzed the model in SAP 2000. I am bit confused and want to know the basic transferring mechanism of forces in such structure.Point that is pinching in my head is that: " TRUSS members only transfer axial forces at joints,no moment." then how a cantilever truss bridge will transfer bending forces to its foundation ?? how fixed support will act in such case? How members of truss will transfer their deflection and bending phenomena to supports?

Help needed in this! Problem attached! STEEL STRUCTURES.docx

Hello, I am designing the mosque in zone 4 . The roof of the mosque is a Truss.I have following questions 1. Do truss rest on the beam ? if yes .? do i have to assign any support conditions ? or etab will selelct by default. 2. what will be the grade of steel for the truss ? yield or tensile strength. some one told me go for A 36 ( 36,58)