Civil Engineering Software - Science topic

I need help with one survey to reach 3000 people (response). I will be really thankful if anyone can reply and share this survey.

https://docs.google.com/forms/d/e/1FAIpQLSf3iKWTc0VkEyPnwX8lIHcVB_4aWJajgbA0_EzkC6HAEpCyHQ/viewform?usp=sf_link

According to my information, the lumped mass is a diagonal mass that has six elements (u1, u2, u3, r1, r2, r3). u1, u2, and u3 have a value equal to (ml/2) while r1, r2, and r3 have a value equal to zero. In Figure (1-a), the matrix is arranged and constructed correctly, while in Figure (2-b), the matrix is unarranged and constructed differently why?

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

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.

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.

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.

I want to model a Dam in 8 stage.

hello

In order to do my thesis, I need to place the damper I developed at OpenSees on several asymmetric steel benchmarks. For this purpose, to develop asymmetric one- and nine-story structures, I decided to use the method given in the above article, but unfortunately in the article, the structures are parametric and I do not realize this.

Here are some basic questions for me.

One, how the mass and structural members of these structures are defined and modeled.

Second, how can a find period for these structures?

And finally, how is it possible to get the response of these structures under the earthquake record?

My strongest guess is that it is to define stiffness of each structural member as a coefficient of mass or vice versa.

Any help is greatly appreciated.

Take refuge in the right.

i had done some work about the debris flow through the experiment and numerical simulation using PFC3D.the particle velocity cloud figure of particle flow could't be well displayed to the reader.

i am using Abaqus CDP how can i get the parameters of Damages fc , ft and how to apply the eccentric load to a wall supported Pin-Pin ends? tq

I already have application file.

Researchers that is currently using Avizo software. 

There's a pinned, steel I-beam like IPE300, 5m lenght, 300mm height, flange 10,7mm thick and 150mm width, web 7,1mm. It's made from shell elements. I'm trying to do buckle analysis with load of 10kN/m.

First of all, I recalculated 10kN/m into kN/m² (10/0,15(width of beam's flange) ) and put on upper flange. In buckle analysis I get 1. eigenvalue = 5,07. In LTBeam I got 2,81, so I checked the reaction forces in boundary conditions. The sum of vertical forces in reaction nodes was equal to the 10kN/m load (25kN for side).

Then I put concentrated forces (corresponding to the 10kN/m) in every node over the web in upper flange. In buckle analysis I got 1. eigenvalue = 2,30. Reaction forces are OK (25kN for side).

I'm curious why there's such a big difference between those two kinds of load with equal value for beam. I made recalculation for edge load and there's almost the same result as in concentrated forces case.

Good morning,

I am trying to analyze a 2D four-level frame structure that is formed by concrete columns and concrete beams. The original building from where I obtained the frame is a university structure here in Perú. I considered the sections and reinforcements according to constrution plans.

I used user defined hinges that were created by a moment-rotation analysis considerating concrete and steel models. I consider a certain level of axial load in order to obtain moment-rotation diagrams in columns. I didn´t use any automatic hinge definition (ASCE or FEMA) because I would like to obtain results acordding to my own constituve models. I created different hinges for columns and beams and I placed them in every extreme side in columns and beam and in the middle of beams.

The seismic record is Lima 1974 earthquake and I scaled it to a 0.45g aceleration that belong to the maximun aceleration in peruvian seismic resistant norm. The original unit of the seismic record is cm/seg2. I think this is a good level of earthquake in order to generated an inelastic response in the hinges. For that reason I used a scale factor of 0.0247 that means to convert the units cm/seg2 to m/seg2 (x 0.01) and I also considered the value of 2.47 to scale the maximun aceleration of the seismic record to the value of 0.45g. At the end, the scale factor results in 0.01 x 2.47 = 0.0247.

In the nonlinear time history case I also used a initial nonlinear case in order to obtain more degradation (Gravity loads). I also defined geometric nonlinearity parameters in order to obtain more displacements.

The problem is that I didn't obtain a good strength degradation of the hinges and they seem to have a elastic degradation response. For that reason, I ask for your help because I don´t find the problem in the model definition. I check my moment-rotation diagrams and don't have any problem or error.

I would apreciated some help and I share the model definition with all the things that I defined in the analysis.

Thanks.

My model is a raft rested on group of stone column, my phases are as follows:

1: Initial phase

2: Installation (raft + stone column)

3: Surface Loading of Raft

3-1: 40% Consolidation

3-2: 70% Consolidation

3-3: 90% Consolidation

After Calculation I get the same results (Settlement & No of Days and steps of solution) for 40% Consolidation and 70% consolidation, and this does not make sense,

so please can anyone know how can I solve this problem?

* attached photos

Hello!

I am analysing a cable stayed bridge seismic behaviour in Ansys Mechanical APDL, but I have got some problem unfortunately. I wolud like to run multiplie loadsteps in one work session. In every load step I want to prestress a pair of cables so that the other ones are stay prestress free. Every cable in the structure made of LINK 180 element. Here is the snipet of my code where I defining the loads and loadsteps and try to solve them.

!MEGTAMASZTASOK

!///////////////////////////

ALLSEL,ALL,ALL

NSEL,S,LOC,Y,15

NSEL,A,LOC,Y,-15

NSEL,R,LOC,X,0 !MEGTAMASZTAS

D,ALL,UZ,,,0

ALLSEL,ALL,ALL

NSEL,S,LOC,X,0

NSEL,R,LOC,Y,0 !SZELSARU

D,ALL,UZ,,,0,UY

ALLSEL,ALL,ALL

NSEL,S,LOC,X,144

NSEL,R,LOC,Z,-11.285

NSEL,R,LOC,Y,-23.463,23.463 !TELJES MEGTAMASZTAS PILON ALJ

D,ALL,ALL,,,0

ALLSEL,ALL,ALL

NSEL,S,LOC,X,444

NSEL,R,LOC,Z,-11.285

NSEL,R,LOC,Y,-23.463,23.463 !TELJES MEGTAMASZTAS PILON ALJ

D,ALL,ALL,,,0

ALLSEL,ALL,ALL

NSEL,S,LOC,Y,15

NSEL,A,LOC,Y,-15

NSEL,R,LOC,X,588 !MEGTAMASZTAS

D,ALL,UZ,,,0

ALLSEL,ALL,ALL

NSEL,S,LOC,X,588

NSEL,R,LOC,Y,0 !SZELSARU

D,ALL,UZ,,,0,UY

ALLSEL,ALL,ALL

NSEL,S,,,6168,6173,5 !LEKOTES

F,ALL,FZ,-4000*1000

ALLSEL,ALL,ALL

NSEL,S,,,6188,6213,25 !LEKOTES

F,ALL,FZ,-4000*1000

!TERHEK

!///////////////////////////

ACEL,,,9.81 !GRAVITACIO

!KABEL FESZITES

!///////////////////////////

*DO,I,1,2,1

ESEL,S,TYPE,,3

INISTATE,DELETE

ESEL,S,,,3733+2*I,3734+2*I,1,1 !KABEL ELEMEK

INISTATE,SET,CSYS,-2 !LOKALIS KOORDINATRENDSZER

INISTATE,SET,DTYP,STRE !FESZULTSEG

INISTATE,DEFINE,,,,,1000000000 !FESZITESI ERTEK

LSWRITE,I

*ENDDO

FINISH

!MEGOLDAS

!///////////////////////////

/SOLU

ALLSEL

ANTYPE,0 !ANALIZIS FAJTA

PSTRESS,ON

OUTRES,ALL,ALL !FESZITES BEAKCSOLASA

LSSOLVE,1,2,1

FINISH

Ansys solves the problem, but got an error wich says:

*** ERROR *** CP = 626.422 TIME= 17:49:37

LSSOLVE looping is stopped because of a solution error.

In post procesing I have some sort of result, but it has only one load step, and gives a rigidy body displacement (I added the picture as a file).

Do you have any ide what did I mess up? If I prsetess only one pair of cable, and ask Ansys for solution, it perfectly works withou any errors.

My other problem is about elemnt table results. I would like to write out the element table result into a text file, but I don't have any idea how could I extract the results with scripts.

Thank you in advice for your help,

Rafael

In your opinion which is the best software to analyse a 3D frame:

(a) STAAD

(b) ETABS

(c) ABAQUS

What are the merits of your answer?

In pushover analysis,while defining lateral load pattern for there is actually two options available 1. mode 2. ACC. Mode pattern considers the pattern as the mode shape of the structure analysed. What does the 'ACC' mean? how the load is distributed along the structure?

How can I model a three-storey structure in opensees with viscous damper the enters harmonic force to top floor?((for obtaining stories acceleration)

The tensile damage parameter, dt is defined as the ratio of the cracking strain to the total strain. Similarly, the compressive damage parameter, dc is defined as the ratio between the inelastic strain and total strain. In that case won't the expression (4) and (2) in the attached paper always evaluates to zero?

I'm doing an unsteady state project on HEC-RAS, but I get an error the says time series ends before simulation time at the end.

Dear all,

I am writing the Abaqus' output such as stress and strain in a text file. I need to use these as training data. However, the results are repeated and given different set of data because of the differences in the number of iteration.

In the text file I can have the number of elements, increment number and variables but I need the number of iteration as well?

Does Abaqus in Umat output give me just the last iteration?

The attached texts show the data is repeated twice for on iteration and triple for two iterations? (Number of element = 15)

Could you please advise me ?

Best regards

I am using SWAT 2012 New Delhi conference data. when I am using HWSD (FAO) type it is showing that the raster layer hwsd.bil doesn't have attribute table just after its loading ( before defining look up table) as shown in fig 1. and when using SOIL_WATERBASE (faosol.img) it is showing that "I-Ne-3729" doesn't exist in user soil database but it exist (as shown in fig 2.). If I replace it (I-Ne-3729) with some other soil from SWAT default soil of USA, it is showing that - some of the user soil can't be detected by SWAT, should be corrected SWAT RUN.

I have modeled a 3story-3bay frame in Opensees that it has one vertical shear link in each story. I wanna get the deformation of the links to know their rotation, so I've used the below Recorder , but I did not get any data in my outputs.

recorder Element -file data/ele1003Defo.out -time -ele 1003 section 28 deformation;

would you please help me where is my wrong?

So Thanks,

I want to perform analysis on a concrete beam subjected to static load at centre of beam. How can I model steel concrete interaction? How can I model a perfect bond?

when i try to model RC column both ended are fixed with axial load i got non convergence problem at early time ,

meaning if the capacity of specimen is 2400KN according to practical results i got in ansys non convergence at 300 KN only

so i think ansys stop solving when the concrete cover cracks and don't wait until the core of column crushed

i have checked the geometry and the material didn't find any things

so can you give me any guidelines or advice or files in this problem.

my mail eng-mohdhisham@hotmail.com

I am simulating the flat slab model under cyclic loading. I am using CDPM for the material properties of the concrete. In order to define the stiffness degradation in each cycle, tension and compression recovery for concrete should be defined. Until now, I am just assuming the value and do not know how to calculate the precise value. Anyone has any idea where I can fine the articles? Some links would be very helpful.

Regards

 I have this problem the following error message appeared to me

Elements to be separated by cohesive elements are of more than one stiffness number (169 and 172, perhaps more). The CZMESH command is ignored

I am trying to modeling  the debonding between concrete and CFRP using 2D analysis. in order to present the debonding I have to use the CZM with contact element. how could I solve this problem could you help me?

after generating the target element and the contact element iused the following command

TB,CZM,3,1,1,CBDD

TBDATA,1,C1,C2,C3,C4,C5,C6   ( HERE I PUT THE VALUES THAT I CALCULATED FOR (C1,C2,...)

R,1

RMODIF,1,3,-1E6

RMODIF,1,12,-1E6

CZMESH,CM_1,CM_2

after that the error message appear how could I solve this problem (the attached photograph show the model with error message. any answer ?

Bridge is of a 175m span, post-stressed cables, Software preferably in Sofistik AG, could be in Autodesk Robot 2012.

For Curve Segment Cable Stayed bridge. What is the design criteria for max. twisting moment to find manually as per IRC or lrfd or any other standard. or a any equation related to find twisting moment.

Hello everyone

I am simulating the suspension bridge given on the pictures by ANSYS workbench.

However, I just add the earth gravity force(self weight ) on the structure but it has exceeded the allowable deflection in vertical direction.

So I was wondering whether the anchorages of bridge use the pull force to cancel the self weight of bridge?

I will very appreciate any replies. 

I'm new in Bridge Engineering

How can I modelling a steel box girder (deck) using Midas Civil engineering software?

for experimental analysis of scour depth at particular site, How can I proceed if I am starter in the civil engg. field ? What experiments are mandatory for this?

I want to design the composite column in ETABS by section designer command method. After the column section made in section designer i assigned this member in building model but in after the placement the design procedure shows as the concrete frame design instead of composite column design. what should i do in this case? how can i change the design procedure?  

I've modeled a simple 2 DOF structure in ETABS then manually computed the modal analysis

I used mass story and story stiffness on ETABS data table

but when i compared my manual computation eigenvalue with ETABS eigenvalue, they both not the same

i'm really sure that my manual calculation is correct, can you please help me to find the ETABS modal analysis calculation?

simple 2 DOF structure -> 2 story shear building (only Ux or Uy analysis direction activated)

I found that this only occur if i run model analysis in 3 dimension structure

i've made 2 dimension frame and run modal analysis on it, and the eigenvalue from my manual calculation with program calculation are same

i am comparing the results of various bracing system for  industrial structure.

while i analysing the structure with X and diagonal bracing it shows less lateral deflection 7-18 mm and 4.73-8.95 mm under various seismic zone.

but in case of K bracing and V bracing it shows large value around 2000mm and lots of instability at joint how do i solve it and whats the reason.

what should i do for getting small displacement

I have a building plan in 2d format that I want to convert into 3d, kindly suggest recent software available. 

steel frame design

I am trying to model reinforced frame section in 2D using tno diana fem software. How can I define detail reinforcing of X-section in 2D model in TNO DIANA?

hi,can anyone help me about modelling of "LSF . i am try to model a hystersis loop for a gypsum panel shear wall and use of Pinching4 Material. but i can't calibrate the parameters of this Material. can you guide me about this issue? thank

I am currently modeling a simple truss with Newmark Method (time integration method) on SAP 2000, I have read some of article about process of time integration method.

But since I try to compare the "show plot function", it has different shape with the time history input. (please take a look to the picture below)

Anyone who ever use linear time integration method specially newmark method. I hope you have time to help me.

Regards,

Ichsan

I want to know any info about undex and modeling to fem analyze 

Which has better strength; circular, square, rectangular, or any other cross-section of RC columns; if all have the same area, main reinforcement, f_c’, and f_y ?

Hi everybody,

I am currently trying to create a numerical model of a Bögl slab track and I was wondering which is the simplest way to simulate the rail pads between the sleepers and the rails. 

I would appreciate any kind of help, thank you.

I need these values for modelling of Hostun Sand in Abaqus Software

Dear all, 

I am trying to model pile soil interaction. I have a short rigid pile in undrained clay, I use C3D8RP for my soil and C3D8R for my pile. At this stage I used Mohr-Coulomb model. I can see that my Geostatic step gives the correct values of displacements and stresses, but when I go to the results and I run Animate Time History , I can see that the pile punches into the soil under its self weight and the geometry of the pile changes (Diameter increases) and the soil disturbance is very strange. 

Is there any way that I can model the case without having the pile sinks into the soil under its own self weight please?.

I appreciate your help , and thank you in advance.

I want to model adobe brick as smeared cracking and mortar as zero thickness cohesive element but I dont know from where I can start. What are the data needs to be entered for smeared cracking and zero thickness cohesive element?

I am trying to simulate 1D site response analysis and then to compare with some other software i.e openSees and DeepSoil. Unfortunately, I am new to this software and having a difficulty in understanding. If anyone has Linear, Equivalent or Non-Linear analysis file in LS-Dyna. Please share with me. 

I'm thanking you in advance

The research is the simulation of the embankment subject to the cyclic loading.

The model is  built in PLAXIS 3D. After finishing the structures stage the Volume of foundation;  soil; facing disappear in mesh stage then it can not perform the mesh on it.

I’m trying to make a moment rotation hysteresis diagram for an HSS to HSS connection in ANSYS. To be able to get the hysteresis diagram, I applied a cyclic loading protocol using a remote displacement at the end of the beam, defined in several analysis steps to represent the displacement at each cycle. Knowing the displacement, it is very simple to determine the rotation of the connection. Nevertheless, I’m not sure of the best way to determine the moment at the connected column face to build the hysteresis diagram.

My question is, do you have any suggestions of a method to obtain results for moment at the column face?

Attached is a picture of the model of the connection that I am using.

Thanks in advance for any help,

Martin

Hey everyone, 

I am now creating a 2D bridge model for the following concrete bridge. It has two spans. The bridge superstructure is basically a concrete slab, with the middle fixed by a shear wall and the two supports built in the abutments. 

My aim is to obtain the natural frequency for this bridge; however, I am not sure what boundary or constraints should I put on the bridge supports. Can someone help with this? 

Currently I am designing a building (width=35 m) over 2 layers of very compressible soils with 35 and 10 m thick and Cc arround 5. Below them is a very stiff soil.

I decided to improve those layers with rigid inclusions, but I do not know how can I introduce the influence of the rigid inclussions into the consolidation (settlement) analysis.

Can anybody help me with this?

Note: Maybe the obvious solution could be to have a deep foundation to the stiff layef, but it is not feasible beccause of a regional settlement could cause an apparent emersion. 

I have completed BE in civil engineer and a native of Nepal. And I want to do research regarding the buildings damaged in the Nepal Earthquake 2015. I have the knowledge but don't know how to start one

Hello everybody

I'm using opensees to simulate SSI problems. I modeled the problem using direct method and now I want to know how can I connect my structure to the soil media. I used a rigid beam as foundation (foundation was not designed) and connect it to soil surface without any special elements ( equalDOF was used to constrain the beam and soil movements in X and Y directions). But drift results shows the rocking doesn't happen in correct way. I need an idea to connect soil and structure.

thank you

I have modeled a mortar layer sandwich between two single adobe brick. I have given an contact interaction between brick and mortar. I have applied compressive stress of 5 N/mm2 on top of one brick and given pinned condition Ux=Uy=Uz=0 on the base of the other brick. The model run fine with 5 N/mm2 pressure, but when I increase it to 6 N/mm2, the solution does not converge. The model is shown in figure. The step time is as:

Time period 100

Max no. of increment 1000

Initial INcrement size 0.0005

Minimum 1E-300

Max 100

Hello everyone, I am designing a 7-story steel building using STAAD Pro software. I made it and when I saw it in render view, it showed intermixed I sections at column beam joints. What type of joint is that?

I have modeled a bridge using the bridge modeler , and i want to add rollers in mid span to simulate the bent behavior because i do not have the exact dimensions and properties of the bents .   

Civil engineers build the 15000 ton and 200m long bridge by and parallel to the existing tracks. When completed, rotate the bridge some degrees to make a seamless connection with the rest of the viaducts&.

Dear all,

I just have architecture drawing of double-deck circle tunnel. Anyone can help me about structure drawing. I want to know their reinforcement, just same shape, dont need identical size.

Thank in advance!

Hello,

Eurocode 2, 7.3.4 (3):

"In situations where bonded reinforcement is fixed at reasonably close centres within the tension zone (spacing <= 5(c + Φ/2)), the maxiumum final crack spacing may be calculated from expression (7.11)"

srmax = k3 c + k1 k2 k4 Φ / ρpeff          (7.11)

and 

"Where the spacing of the bonded reinforcement exceeds 5(c + Φ/2) or where there is no bonded reinforcement within the tension zone, an upper bound to the crack width may be found by assuming a maxiumum crack spacing srmax = 1,3(h - x)"

where x is the compression zone in pahse 2.

And there is my question:

In members under uniaxial tension there is no compression zone (x = 0). Does that mean, that for such kind of elements a maximum crack spacing is equal to      srmax = 1,3 h?

Or maby this rule applies only for members with existing compression zone? If yes, than what is the upper limit for crack spacing for members subjected to tension?

Best regards,

Bartosz Grzeszykowski

Dear all, My model is a raft rested on number of piles, the piles are soil volumes.

The question now for plaxis 3D users:

How can I improve the mesh quality ? should I local refine the mesh for the volume containing the raft and piles? and what value to put it in Fineness factor? and what will be the global mesh density ?

Thanks in Advance

I am having trouble finding information on the use of a 3D IFC file within a building automation program, there seems to be no program that can interrogate a 3D file. 

- Slip Failure line

Just as the question.

I've got a detailed and systematical introduction on numerical model of the soil-pile intercation on a sesimic load in the dissertation from the attached link. In figure 3.11 and 3.22 (the atteach picture), page 72, it is reported that real part of the impedance function is obtained from FEA,here Abaqus.

But anyone can tell me how to work it out?

can the analysis be implemented in universal step?

Is this method suitable to a harmonic load uniformly acted at the pile top?

Dear researchers,

Do you know how I can model TNT blast loading at ground level in Abaqus? 

I'm modelling metro tunnel in Abaqus to study blast loading effect.

_

I need to perform a Time-History Analysis on a building frame embedded in soil using LUSAS. It is a Dynamic SSI Problem, I have tried to perform the analysis by deconvoluting the Earthquake Data of Response Spectra (IS: 1893-2002) . Deconvolution is done using "STRATA" and "DEEP SOIL" (Which appears to be correct) but the problem is that after applying the deconvoluted data at the soil support (fixed in all translations at bottom and fixed in x and z in lateral direction) and recording Secondary Response Spectra at the soil top. the recorded Secondary Spectra is very high when compared to the Target Spectra that I have considered (IS: 1893-2002).

I have come through the topic of Bicanic Bounday Condition used in LUSAS but how to use it and how the load is applied and results are processed??

I modelled a helical pile (with a mass at the head) installed in dry sand undergoing seismic shaking at the base. I am trying to mimic a full-scale test we performed in a shaking table. I am using ABAQUS.

My modelling steps are as follows:

Step1: Initial conditions which consists of applying fixation at the base and lateral sides of the model. I also fixed the empty void in the soil (Where the soil will be placed, I know this does not include the effect of driving the pile). I applied the initial state of stresses using the predefined field in abaqus.

Step2: Geostatic step. I applied gravity loading on all the soil. At the end of this step, I checked the stress states with depth and they are matching my initial calculations and all deformations are at of the order of 10^-7. (should they be smaller?)

Step3: Removed fixations at the void inside and activated the interaction between the pile and soil. Also applied the gravity load of the pile so that it will settle slightly in the soil. Checked stresses here and displacements and they look okay.

Step4: Applied the time history of my earthquake at the base. At the first 3 seconds during shaking the soil didnt show any settling, however during the strong shaking the soil starts to settle and reaches 0.5m displacement downwards at the surface. (look at the attached images)

I cannot think of any reason causing this. Your help is greatly appreciated!

Attached are the input file used for the analysis (took about 5 days to run) and several screenshots of the deformations during the shaking.

Also attached several videos of the run in difference scaling factors.

I have modelled masonry building in abaqus using homogenisation technique but i m getting some errors in analysis so now i want to model  masonry building by modelling separate brick and mortar interface so i want to know the procedure for modelling brick and mortar interface and cohesive elements,which type of element should i select to model separate mortar and brick.

I will be be grateful 

Thank you in advance

Dear All,

I want to calculate the minimum distance between randomly distributed small squares as shown in the attachment. The length of the small squares is 0.016667 and the length of the total length is 1. Right now, I have the data of the centers of the small squares. I want to find out the minimum distance between these small squares.

Any suggestion would be appreciated.

Thank you.

Best Regards,

Bill

Dear all,

I am going to model ground water level falling in order to determine soil layer settlement.

I would be so grateful if anyone could help me.

I need to study the effect of stiffness contribution from reinforcement and get load-displacement curve considering interaction of reinforced structures/composite structures. Since I'm dealing with large infrastructures (in my case bridges), what would be a user friendly (not necessarily complicated) finite element software for modelling such responses in large structures?  

My available options (those I have the license) are Ansys, Abaqus and Ls-Dyna

Thanks heaps, 

Dear Researchers, 

I modeled an RC wall that is subjected to lateral blast pressures using surface to surface contact, where a finite thin part of the underlying soil modeled as an elastic material with only 50mm thick. The bottom surface of that part constrained from movement in all directions, and upper surface connected to the bottom of wall base using surface-to-surface contact using a high coefficient of friction equals to 0.8. After the solution of the dynamic explicit problem, it is found that the wall is moving (slide and overturn) without stoppage till the end of step time! even when subjected to very low levels of loads? When the step time increased, the wall still moves till the end of extended time. I'm expecting that wall shall move certain distance then stop. Is the type of contact i'm using suitable? and how to model such contact by another ways?

Kindly help