Science topic

# Structural Analysis - Science topic

Structural analysis is the determination of the effects of loads on physical structures and their components. Structures subject to this type of analysis include all that must withstand loads, such as buildings, bridges, vehicles, machinery, furniture, attire, soil strata, prostheses and biological tissue.

Questions related to Structural Analysis

The purpose of earthquake engineering is not to build strong and earthquake-resistant buildings that do not experience the slightest damage in rare and severe earthquakes. The cost of such structures for the vast majority of users will have no economic justification.

Instead, engineers focus on buildings that resist earthquakes' effects and do not collapse, even in severe external excitations. It is the most important goal of international standards in the seismic design of buildings.

Below I have mentioned some crucial points in reducing the seismic demand in reinforced concrete structures.

**If there is anything else that is not on the list, feel free to append:**1- Selecting suitable construction conditions with the desired soil type of seismic design

2. Avoid using unnecessary masses in the building

3- Using simple structural elements with minimal torsional effects

4. Avoid sudden changes in strength and stiffness in building height

5. Prevent the formation of soft-story

6. Provide sufficient lateral restraint to control drift through shear walls

7- Preventing disturbance in the lateral behavior of the structure by non-structural components

Dear Colleagues,

This Special Issue, "Numerical and Computational Methods in Engineering", aims to explore the latest advancements and applications of numerical and computational techniques in various engineering disciplines. It provides a platform for researchers and practitioners on which to share their innovative methodologies, algorithms, and computational tools that facilitate the analysis, design, and optimization of engineering systems.

The scope of this Special Issue encompasses a broad range of engineering fields, including but not limited to civil engineering, mechanical engineering, electrical engineering, aerospace engineering, and chemical engineering. It welcomes contributions that address fundamental principles, the development of novel algorithms and computational techniques, the implementation of computational models, and practical applications in a diverse range of engineering domains.

Keywords

- applied mathematics
- numerical methods for partial differential equations
- computational mechanics
- optimization algorithms
- structural analysis
- heat and mass transfer simulation
- computational electromagnetics
- multi-physics simulations
- computational materials science
- high-performance computing
- data-driven algorithms
- big data analysis
- machine learning in engineering

While doing a structural analysis to check the plastic limit load of a component, the solution stops shortly before the end of the time step after successfully solving several substeps. I'd like to see the loads corresponding to the converged substeps. Is it possible to retrieve these loads through some apdl command?

I’m working on research that will compare the performance of different structure systems of high-rise buildings, I’m going to use ETABS in this comparison, so I need to figure out exactly how does it calculate the wind load, so I took a very simple 3 floor building, the height of each floor is 11.48 ft and building is 98.5 x 98.5 in plan, then I will use the following: -

gust factor = 0.85.

Kd = 0.85.

Kzt = 1.00.

Imp Factor = 1.00.

Exposure C.

Wind Speed = 100 mph.

Kz (1) (First Floor) = 0.849, Kz (2) = 0.928, Kz (3) = 1.01.

qz(1) = 0.00256 x 1.00 x 0.85 x 0.85 x 0.849 = 18.47, qz(2) = 20.2 , qz(3) = 22.00 , qh = 22.00.

Windward Side

P(1) = 18.47 x 0.80 x 0.85 = 12.56 ft/lb2, P(2) = 13.74 ft/lb2, P(3) = 14.96 ft/lb2.

F(1) = 12.56 x 98.50 x 11.48 = 14 206 lb, F(2) = 15 541 lb, F(3) = 16 920 lb.

Leeward Side

P = 22.00 x 0.50 x 0.85 = 9.35 ft/lb2.

F = 9.35 x 98.50 x 11.48 = 10 575 lb.

I apologize for the very long introduction but now comes the problem I face, total force from the windward side = 46 668 lb, total force from the leeward side = 31 727 lb, total external force = 78 395 lb, I have problems calculating the internal pressure to get the final value that’s on ETABs ( 64 464 lb), need assistance please.

How to show two peptide structures side by side on Pymol. I have 100 PDB files. I want to show all the 3D image structures side side in a two-dimensional array form. How could I do the same in Pymol?

There is nothing worse for curb appearance than chipped and cracked concrete, particularly in steps. But you don’t have to put up with that blight any longer. By the result of weather changes exerted on an existing construction for prolonged time, it causes contraction and expansion those gradually results concrete steps cracks and break up with time.

Dear researchers, I would like to get expert opinions on

**how to fix this issue with,****optimum efficiency**

**low cost**

**prolonged sustainability**.

Your answers are highly welcomed.

Are its faces polytopes?

Is there any information in the literature on the geometry and topology of saddle polyhedra?

Can we use them to construct structural triply periodic minimal surfaces?

An attempt to answer some of these questions in:

Complex graphical sketches are highly involved in Culmann's methods. Therefore, it is highly prone for getting deviations in magnitudes for resultant pressure on retaining wall. I would like to get suggestions from RG colleagues on why Culmann's graphical approach is mostly preferred in many research papers albeit Rankine's method is easy and precise in terms of equations and substitutions. I would welcome answers from both theoretical and practical perspectives.

Can you please recommend me any useful material that will help me to understand CDP model generally used in ABAQUS for concrete materials? I have read some fundamental papers like Lee and Fenves, Lubliner et. al., etc. to understand the theory behind it. I got it to some extent. Now, I am looking for something that describes CDP from practical point of view. My main goal is to understand the output that I am getting from my analysis.

Any sort of information will be greatly appreciated.

I have results from a load-deflection curve that behaves non-linearly. I need to convert this to a stress-strain curve and/or find the

**final Modulus of Rupture (MOR)**.To do so, converting the deflection into strain is possible as per ASTM D790

εf = 6Dd/L^2, where D is the maximum deflection, d is depth and L is the span length.

I would like to convert the load to stress as well, however, the conventional equation from beam theory is not applicable past the yield point,

σf = 3PL/2bd^2, where P is the load.

I'm aware that it somehow involves the neutral axis and the modified I (moment of inertia) but struggling to make sense of it. The end goal is to find the MOR.

Any help about this is appreciated :)

I am writing a FEA solver (using MATLAB) for computing stresses and stresses in a 2D rectangular plate with an elliptic hole (rotated to an angle). I computed the global stiffness matrix using Gauss quadrature (3 gauss points) and have also calculated stress and strain in each element.

How do I calculate the nodal stresses from the element stress values. I think the element stress values that I obtained are calculated at the centroid of each element. How do I extrapolate/interpolate these values to get nodal stress and strains?

Please advise with some resources or tutorials or solved examples.

I have performed a certain set of nonlinear dynamic analyses on an RC (Reinforced Concrete) frame that I designed on SAP2000 using the Indian Standard Codes. Since the numerical model is not based on any existing building, I fear that someone might ask me how I would validate my model, which on their part, is justified. What could I possibly say as a satisfactory response?

For some reason, many people are often reluctant to share their design details, so the question regarding validation seems a bit tricky.

Thanks in advance.

I understood SM is moment per unit width. But i dont know how to get integrated moment at mid span.

Then I tried to use free body cut to show mid span moment. (SI unit:force=N, length=mm)

However, I found that the moment I get for 500(D)x100(W) and 500(D)x400(W) are the same (e.g both 6.1e8) from free body cut, if that moment multiply flange width, total moment will be different in section 500x100 and 500x400 but their length and load are the same.

So I just wonder if moment from free body cut(blue arrow) is already represent total moment at mid span?

Thanks

I have created a model of high rise tower and tried modal analysis in Ansys workbench Mechanical, but I am not getting frequency values and mode shape. Value of frequency is showing 0 at all modes. Can anyone suggest why this is so?

As we studied in our academic courses, we know several shapes of beams:rectangle,special shapes and T or L beams.

So in softwares such as Etabs and Robot, are they take into consideration L or T shape beams?

The most venerable professors and research scholars

Your critical comments, valuable opinions, scientific facts and thoughts, and supportive discussion on how can structural grammar and IC analysis be justified in the recent pedagogical and enhancement trends in EIP for EFL adult learners.

I shall be thankful sincerely for your kind participation.

Best,

Dr. Meenakshi

I found that modal frequency results between Opensees Navigator and hand calculation is different.

I assumed a simple truss model : cross section 0.04 m^2, mass density 5000 kg/m^3, elastic modulus 200 GPa, 3 nodes, 2 elements.

This truss model has 2 mode and 2 modal frequency. My hand calculation modal frequencies are 711.7625 hertz and 711.7625 hertz, respectively.

However, Modal frequencies from Opensees Navigator are 142.3525 hertz and 142.3525 hertz, respectively.

I wonder why two results have different. Does Opensees Navigator have postprocessing?

I'll post my Opensees Navigator files. Please describe the reason why two results have different.

In his name is the judge

Hi

I think the best way to assign the nonlinear effect of steel components like beams that to model it with a plastic hinge.

So To build a nonlinear model of a one-story steel structure I use the Modified Ibarra – Krawinkler model to model my beam. In fact, I model a beam with two hing (zero length element) at the start and end and one elastic beam in the middle.

I used material developed by Lignos and Krawinkler named uniaxial material Bilin and here is more information about this material

After all, when I extract the output belonging to the stress-strain of this material under seismic loading like Kobe I get something like this diagram. (kobe0.5g) based on

*"Ibarra L.F., and Krawinkler, H. (2005). “Global collapse of frame structures under seismic excitations”, Rep. No. TB 152, The John A. Blume Earthquake Engineering Center, Stanford University, Stanford, CA."*

named article and this diagram (ref1) the stress-strain shows the right modeling and performance. consider that my record is near fault and the diagram of reference also belongs to near-fault loading.

If I use the 1g scale for the Kobe record I get this diagram (kobe1g) and here is the diagram of the 2g scale for the Kobe record (kobe2g) So my best shot is this when the record multiply and the ground accel become higher the material reaches the capacity of its deterioration very more quickly(In fact after a short time the strain of material switch between 1e10 an-1e10 and strain is between about -2 and 2) but it's a little non-sens for me in the other hand there is one benchmark( in the reference is named it before this benchmark is for standard loading) diagram for this material stress-strain (logos) and my diagram is different with it.

In the end here are the 1M$ questions

1- why when I give more scale to record the diagram become like that?

2- and why my diagram is different from the benchmark stress-stress of material?

Any help is greatly appreciated.

Take refuge in the right.

Hello All... I am trying to install Gromacs on windows using conda i have attempted to run "conda install -c bioconda gromacs_py" but it's not working. Any recommendations shall be highly appreciated.

In his name is the judge

I want to build some parametric structures. my objects is period of first mode, eccentricity and (frequency of torsional mode/frequency of transitional mode). So I decide to use NSGAII for make my parametric structure.

Inputs of optimization are transitional mass, rotational mass, length and width of structure and objects are period of first mode and (frequency of torsional mode/frequency of transitional mode) and in each one I assume eccentricity constant.

So I think there is a problem. I think there is a relation between rotational mass and transitional mass with respect to length and width of structure and eccentricity of mass.

If my guess is true I have to remove rotational mass from my inputs and use the relation instead.

So my big question is

Is there any formula to evaluate rotational mass based on dimension, eccentricity and transitional mass in rectangular plan?

wish you best

Take refuge in the right.

How to find the rotational mode shapes using an accelerometer that can measure the translational mode shape only in the modal analysis experiment for a cantilever beam?

I am modeling an underground structure with fixed support conditions around the exterior walls. I would like to apply different ground acceleration time history data into specific nodes (joints) of the structure. Is this possible in SAP 2000? I would appreciate any guidelines. Thank you very much!

in the flexural 3PB test, a concentrated displacement load would be applied to the top middle point of a beam. For modeling one-half of the beam using symmetry, which nodes or edges do you think should the roller and load point be assigned to avoid coincident of the BCs and errors relating to stress concentration in a nodal load point (after meshing, image attached)? is it not a better idea to assign the displacement load directly to the whole side edge using these BCs ( U1=0, U2=Value, U3=0, UR1=0, UR2=0, UR3=0)?

any idea would be appreciated.

I am doing a structural analysis of natural fiber composite. I need to insert downward speed on a plate placed on top of a body and the other plate placed at the bottom of the body will remain fixed. I need to solve this problem to see the critical load and deformation induced in the body due to application of speed on the upper plate.

I intend to perform a steady-state structural analysis on dog bone specimen that is loaded axially. The young's modulus is 200.02 GPa and a poisson ratio of 0.39. The analysis is intended to be in a linear state. This is intended to be performed on the APDL section. I am looking to become more of an expert in this field so any help in understanding this better would be appreciated.

Also experiments have been conducted so I do have stress vs strain data to use for non-linear analysis, however I am not very on how to go about it as I have found it difficult to model non-linear problems on ANSYS APDL

In his name is the judge

Hi

There is a fuzzy logic control system in python. The system contain 2 inouts and 18 outputs.

inference of system is mamdani and shape function used to be guassian.

Then in term of refine performance of the controller I need to optimize specifications belong to shape functions of both input and output. In order to that I need to use multi objective optimization.

We have 2 input and 1 output in case of this problem. I have developed 3 shape functions for each entrance and 3 for output and the shape function is gaussian so we have 18 parameters totally.

I defined my problem as a function in python. But notice this I there is not any clear relationship between input and output of function. It’s just a function which is so complicated with 2 inputs and 18 outputs.

I made my decision to use NSGAII algorithm and I really don't want to change the algorithm.

So I try every way to optimize my function but I didn’t find any success. By searching about python library which can do multiobjective optimization I find Pymoo as the best solution but I really failed to optimize my function which is complicated custom function, with it.

So It’s really my pleasure if you can introduce me a library in python or suggest me a way that I can use Pymoo in order to this aim.

wish you best

Take refuge in the right.

Hello everyone, I was modeling pultruded GFRP rectangular hollow sections for ITF boundary conditions. However, i am facing some errors while executing the job analysis. Can you please guide me how can i remove these errors from my model.

I have attached the abqus model, errors file and respective material properties.

Thanks you!!!

In order to analyze a component on which case hardening is done for a certain depth, for fatigue life.

I have done a comparison by applying the hydrostatic pressure on the middle and top of the shell curve surface (Section Assignment: Shell offset = Middle or Top surface in Abaqus). In the case of the middle surface minimum deflection is 6.115 mm, but in the case of the top surface, the minimum deflection is 12.18 mm. The curve plate is simply supported from three sides.

I have attached images of the results.

Could anybody tell me, which one is correct and why?

Thank you very much

Dear Researchers,

I am looking for methods to mesh a twisted blade in order to get more structure mesh.

I tried several mesh size yet the quality metric are a bit bad.

I am analyzing regarding the skewness and the orthogonal quality.

My objective will be performing modal and harmonic in order to determine the stress distribution adequate to the natural frequencies.

Thanks in advance for your advise.

In recent years, there has been development of some innovative construction technologies that are changing the way we build. There are many new technologies that will have a significant impact on the future of the construction industry.

Today, construction companies are able to complete projects more quickly and efficiently than ever before. There are new technologies in demand for the future that will help with accuracy, sustainability and faster construction.

**Based on your point of view, what are the types of construction that can be used in future?**

I am looking for information on the pressure tree roots (by expansion) can exert on structures as retaining walls and quay walls. Failure of retaining walls by root pressure is very common. Is there any way/model to determine this load?

In his name is the judge

Hi

I'm trying to make a fuzzy controller in order to optimize my absorber performance in opensees(in python).

I use adaptive neuro-fuzzy inference system (ANFIS) toolbox in matlab to make fuzzy system as controller.

input data for fuzzy logic system are acceleration and velocity of absorber and the output data is force wich controller send it to absorber for performance improvement.

in fact i want controller learn ,based on velocity and acceleration of a point of structure, how much force need for turn structure into it's balance position.

note that quantity of force determine by fuzzy controller system and applying force part of absorbr job.

logically we have to assign come load to the point of structure wich absorber locate there and then get acceleration and velocity of absorber as input training data of fuzzy logic system.

but i realy don't know how can i do this.

note that i want to give force to structure in balance position, in the otherwise i think make train data is possible when using dynamic loading so i entirely confused here

if you have any suggestion i realy eager to hear it.

wish you best

Take refuge in the right.

In his name is the judge

Hi

for using matlab facilities especially matlab controller like fuzzy have to sending and receiving data between matlab and opensees, in fact i want send two data as fuzzy controller form opensees to matlab after each time history step in opensees and then matlab send back one output to opensees.

to achieve this i have to connect matlab and opensees with openfresco it means i do hybrid simulation.

first is this possible to do this?

second is there any one do work like this, do hybrid simulation generally or specifically do hybrid simulation between matlab and opensees. if yes i am very thankful to share work with me or for some aim.

have to say i prefer not to use openseespy and i almost read all example and guide in openfresco site and even on each site but i cant do this right.

Any help is greatly appreciated.

Take refuge in the right.

In his name is the judge

Hi

I want design cotroller in to control active force of damper.

On this purpose, i analyzed structure with damper, wich is tlcdg, and get data whic use for generate controller. data are accleration and velocity of damper as input and dampers force as output ( i mean force wich made by own damper under earthquake excitation, not active force).

here is anfis properties :

number of inputs are 2

number of outputs is 1

generate fis method is grid partition

number of membership function are 4 for each input

input membership function type is guass2mf

output membership function type is linear

opt method is "hybrid".

(have to say i tried different epochs membership function , .....)

Unfortunately anfis toolbox in matlab refuse to train and build Suitable fuzzy controller wich means error is too much in training, so this answer is not acceptable.

i have some idea for make it true but i'm not sure.

here is my ideas :

* first i think train controller with more or less data ( training data are about 2000 wich is under 100s earthquake excitation but when i reduce earthquake excitation to 10 or 15 seconds the error is acceptable however i think this solution is not good.)

* second maybe i must try one damper for training.

* the last idea is to assign force on the damper location and get acceleration and velacity for generate trianing data.

here is my data and shot frome my try.

Any help is greatly appreciated.

Take refuge in the right.

I'm preparing Msc thesis regarding base isolation of buildings using rubber bearings, but before commencing my study I need to numerically verify an experimental work / shaking table test, but the problem is that I,ve been searching for quite a long time but yet to find anything useful, I've found many good papers but with missing information that makes modling of the experment imposible, thats why I need assistance in finding a proper research with complete information.

Which is the best way to attach the IMU sensor on the cantilever beam to measure it's acceleration so we can avoid errors and noise as much as possible ? (Is it by glue for example or wax or any other way) ...?

Which is the most crack direction is studied in a metal cantilever beam? When the crack is vertical or horizontal? (I mean if the crack propagates vertically or horizontally?)

And how each type of excitation(Bending, Axial,..) is sensitive for each type of crack shape and orientation?

I am asking for test purposes .. So I can use the crack direction that is more sensitive for measurements in my experiment.

Is there any effect of damage shape on the damage severity? And which do you expect has more severity of damage the holes shape or longitudinal shape? And why?

The psychological, inner mental activity, is a process. Usually it is hard approaching dynamic phenomenons by means of structural analysis, where intuitively things are seen in some static way. On the other hand, psychological activity is a very complex issue, and complexity can be frequently managed by systemic structural methods.

I am currently testing a basic design for my research topic with a hollow cylinder.

The displacement was set as 0 on one end as a fix support and -5 in Y direction on another end.

The reaction solution i had is different from in Ansys Mechanical and i believe that the result generated from APDL was wrong.

The last screenshot is the result from APDL using .cbd file from Workbench mechanical

The result is still incorrect comparing to the result from Workbench Mechanical.

What is my mistakes here or any suggestion ?

To whom it may concern...

Case shown in pictures below need to stop in front of it...

Starting with the way of supporting slab before casting.. the question appear...

Based on your engineering opinion, and supporting method that you might used... is what shown in pictures attached ,.. enough.. ?

Then... whom responsibility is that... if slab fail during casting process, as there will be additional loading of pumped concrete and labors also ...? where that will be the most important question....

To whom it may concern...

Case shown in pictures below need to stop in front of it...

What the mean of overload... What will be the meaning of calculated loading before design... and.... What really mean the structural design based on submitted data..

All, in general,.. knows that.. design start with converting functional use of the building to loading on structural element... then start design element by element ...

So, what might be the supposed loading to one story house... based on all adopted code... ? this is the first question..

Then what you think, .. or what the supervisor engineer might think the value of such loading on that slab shown in pictures attached... ? this is the second question...

Then at last... whom responsibility is that... if failure occur...? where that will be the most important question....

Limited education with low experiences causes such cases, ... or... we need to ask the supervised engineer if he care...

+1

I am currently solving a static structural problem using ansys. I have given all the inputs but stress is not transmitting across the body. I have attached the files and I am bit new to ansys. Please guide me through the problem.

Dear all,

I would like to do a welding heat transfer analysis in 2D and map these results to a 3D model for conducting structural analysis. Is there any way to do the same?

Can any one suggest references for the same?

I am doing a 2D pure shear isochoric strain analysis with 20% pure shear in ansys workbench using ansys static structural in ansys workbench. Previously in ansys mechanical apdl, there is a scope to enter displacement as a function of coordinates of nodes. The equations of my constituting boundary condition are

U = 0.2 *X and V = (-20/120)* Y. Here X and Y are the coordinates of the concerned node. How do I use them in ansys static structural analysis? Please guide.

Hello,

I am studying the performance of 2 wing models (with the same size, constraints, loading and material properties but different material distribution) using Nastran. Wing A is lighter and 24% stiffer than wing B and that is demonstrated in the static analysis (under a distributed load on the top skin).

The two wings have about the same fundamental frequency (34.25Hz and 34Hz). Using the relationship f=sqrt(K/m), the difference between the two frequencies should be significant.

Also, the divergence analysis yields exactly the same displacement for the two wings.

Does any one know what could be causing such results? why the divergence displacement is not smaller for wing A (since it is stiffer) and its frequency is not much higher than wing B?

Thank you in advance for your input.

Dear researchers.

I am studying one way FSI using fluent and transient structural, my problem is that when I transfer the result directly from the fluent, I can not observe the correct deflection as the response should be a stepped as the excitation is a step function.

The relative total pressure on the structure surface is correct and I verified the plot.

I think that in transient I could not read the time steps even that I followed the correct step.

one of the solution I crossed with during web searching is to use external data transfer.

I know how to export pressure time value yet how to make the solver know that the pressure zone is as described in the attached picture?

I will really appreciate if anyone could give some tips on the use of Lusas and SAP 2000 software for modeling and structural analysis. Thanks

Can anyone suggest to me method to design fuzzy inference system (FIS) for MIMO structural damage detection (i.e. data distribution on the membership function, parameters of MF, Generate rules ... etc )

In my system there are 3 inputs and 2 outputs:

Inputs: Relative 1st Natural frequency , Relative 2nd Natural frequency , Relative 3rd Natural frequency

Outputs: Crack depth ratio , Crack Length

Note: I tried to use "genfis" By MATLAB it didn't give me reasonable results.

Data science is a growing field of technology in present context. There have been notable applications of data science in electronic engineering, nanotechnology, mechanical engineering and artificial intelligence. What kind of future scopes available for data science at civil engineering aspects in the field of structural analysis, structural design, geotechnical engineering, hydrological engineering, environmental engineering and sustainable engineering?

Hello Researchers,

The FEM discretized (meshed) geometry/domain is considered stiffer than the actual geometry/domain due to the assumption of variation of the displacement within each element. This is analogous to the displacement being constrained to vary in a particular fashion within each of the elements. This results in the stiffness of the discretized domain being greater than the actual domain. As the element size decreases (or the number of elements increases), the constraint on the displacement loosens due to the smaller size of the element and hence, the smaller constraint zone. Thus, the stiffness of the meshed domain decreases and approaches that of the actual domain as the number of elements is increased.

**Based on the above reasoning, the natural frequencies (on increasing the number of elements) must converge from above to the actual value (i.e. converge from higher values to the actual value).**

- Can this be considered to be strictly true?
- Has any deviation from it been observed (i.e. convergence from below or lower values to the actual value) and if so how can that trend be physically explained/interpreted?

I am looking for stress-strain data for steel to input for the plastic properties in Abaqus. However I cannot find any literature or experimental data on the matter. If full data is not available then the strain or deformation rate will also be helpful. Should I assume a 2% strain rate in the absence of other data?

How can I get the equivalent(effective) Young modulus and Poisson ratio of a multilayer structure? A structure like the below picture. the structure is consists of Si, Al2O3, and Al metal thin films. They must be simplified into one equivalent layer.

Thanks.

So If a column isn't casted exactly in the intended location according to the structural drawings, and the centre of this column is moved 3 cm away from it's original location.now in the ACI code, accidental eccentricity is taken into account in the column design equation,so the question is how to check If that eccentricity is within the allowable range? According to the ACI?

While doing profile matching in full prof chi-square value is stuck at 12. When I try to refine u,v,w parameters their value reaches up to 38. What might be the possible reasons for the non-refinement of these parameters?

Structural analysis and morphological analysis

in his name is the judge

hi

I wrot a sub code on opensees for active tlcd or tuned liqiud gass damper (tlcgd) and assign it to some structures, it seems worked correctly.

In next step i want to optimize tlcgds location on each story with some objects like max dislacement or torsion ratio and ... so i have to use multi objective optimization (which may NSGAII algorithm is the best choice) code or toolbox on matlab and simulink. For this purpose i want to run NSGAII algorithm in matlab, then algorithm Calling my code in opensees (tcl) and run it, after that NSGAII algorithm modify damper location (in opensees code) after each timehistory analysis In order to improve objectives and then analysis my code again and again until find best location for dampers.

Note that I actually want to changing dampers location be part of the NSGAII algorithm and the algorithm itself automatically relocation the dampers to get the best answer.

one best solution may use openseespy but i think it's not free access and i can't get it from iran, So i think realyhead Over heels in this case.

Any help is greatly appreciated.

Take refuge in the right.

What can cause severe bending conditions on the wind power plant's tower(only the tower part)? I assume that as the wind hits the blades it create a bending moment which vary linearly from wing tip to wing base. This moment will be transferred from blade's base to the top of the tower ( we have then a model like a beam with one end fixed and a bending moment on top). And I think that this moment has larger condtribution to tower's bending than the force coming from the wind as it hits the structure. Correct If I am wrong.

Hi,

Can any one please let me know how to configure ABAQUS solver for ANSYS workbench? So I can run simulations using ABAQUS solver which are pre-processed in ANSYS.

I read the help file, but I'm bit unclear what to do!

Thanks in Advnace!

Hello friends

Nowadays I am trying to use Code_Aster to simulate CABLE . I want to know how to add a force like this F=0.5*velocity^2 on selected nodes?

And how can people add a triangle distributed force on a moving cable whose coordinate is changing with time .

Thanks for your help in advance.

Is the only way to differentiate between short and long coloums according to ACI is through slendeness ratio? Is there an easier approach?

Structure Erection and Civil Works

1)Brief on civil foundation and, erection of supporting structures.

2) Fixing the foundation of the structure and, the grounding considerations.

3) Installation of mechanical structure

4) Foundation: Reinforcement and Shutting other balance of systems

5) Mechanical safety aspects.

What should be done if items did not load in EFA?

should they be discarded? Or that means that they are unique and do not have partners?

What if these items are important or represent our dependent variables ? Can we include them as single items?