Modeling RC Column subjected to blast loading using LS-Prepost + LS-DYNA (S-ALE)

[@alliswell.-560]

Thank You. I really appreciate that. Please continue shooting another LS-DYNA videos on RC structural elements.

[@navyamupparaju1529]

How much blast load is applied in this video?

[@dfetech]

@@navyamupparaju1529 Sorry for late reply. The blast load is define at *INITIAL_VOLUME_FRACTION_GEOMETRY and use *INITIAL_DETONATION to control the position & lighting time of the detonation point. LS-DYNA take the density of “Standard” TNT to be 1.57g/cm3 & detonation velocity to be 0.693cm/us. In this model, we use sphere with radius of 10cm as the TNT. To define the blast load you want, you need to use approximate the equivalent mass of TNT. For more info, please refer to LS-DYNA KEYWORD USER'S MANUAL Volume I.

[@riyansireddy4143]

Sir can you do video on beam

[@hamzagungor3029]

Please one extra initial volume fraction geometry video. You are perfect .

[@erinpratt886]

Question; at the end of the first video, where you create the column model, the list at the top left only had Assembly 1 and FEM Parts. But, at the very start of the second video, there is now "Geom Parts" and "Part 1". Is there a missing step between video 1 and 2?

[@dfetech]

Hi. Sorry for the slow reply. You can right click the Feature Tree to show/hide the "Geom Parts". Thank you.

[@shriyaverma2565]

What will be erosion criteria for concrete MAT_072R3 ? And how can we find depth of crack in concrete? The concrete slab is subjected to airblast load.

[@TấnĐạtPhan-s7c]

at 6:25 , In the *MAT_ADD_EROSION section, how can the parameter MXEPS be calculated? Is it computed as the ratio between the maximum principal stress and the elastic modulus? However, since steel has a plastic deformation stage, how is this parameter calculated for steel?

[@dfetech]

Hi TấnĐạtPhan-s7c, MXEPS in *MAT_ADD_EROSION is variable to invoke a failure criterion based on maximum principal strain. For more info on *MAT_ADD_EROSION, please refer to LS-DYNA Manual Volume II. To better describe the material behavior, you may consider using other advanced materials like *MAT_JOHNSON_COOK, *MAT_PIECEWISE_LINEAR_PLASTICITY, etc. Thank you.

[@duongng99]

i have a question for u. how to create model reinforce concrete with steel bar? i need to create model concrete in real live to simualate. Thank you so much

[@riyansireddy4143]

In which direction we hv to give 3rd node direction for stirrups and main bars in beam?

[@riyansireddy4143]

Sir how you created stirrups?

[@simonematerazzo7020]

at 19:03 it appears a " 1000 auto created PART". I don't understand how you can add an auto-created part. Can you please explain? Thanks. Great tutorial anyway.

[@dfetech]

Sorry for the late reply. The part ID 10000 is the S-ALE part, it is created automatically after you define the DPID in *ALE_STRUCTURED_MESH and accept this keyword. You can change this DPID to any value, but please make sure all the PID refer to the S-ALE are the same, e.g. in *CONSTRAINED_LAGRANGE_IN_SOLID, otherwise your model wouldn't work.

[@navyamupparaju1529]

How much is the blast load applied here?

[@gautamkumar-lu3xx]

I want to join Dfetech please tell me about course

[@zahirshah22]

Could you share the 3d CAD model used in the simulation?

[@dfetech]

Sorry for late reply. You can create this model in LS-PrePost directly. See this video >> kzbin.info/www/bejne/gYvEl6CIrZecq7M on how to create it.

[@JH-nn6oi]

Could you share .K file? No matter what I do, the results of the analysis are not good. (No load is applied to the reinforcing bar, and the concrete element is not removed.)

[@song-up8fj]

I don't know where I'm going wrong, it doesn't even work.can you share your k file, i want to see why i can't

[@shiqizhang3532]

it's same as mine

[@shiqizhang3532]

the lstc suggested me that use*beam in soild and it work ！

[@shiqizhang3532]

I got an error when it running that beam 228 has zero area this message had occured lots of times

[@shiqizhang3532]

I get it it lost the area para in the section on beam

[@zafertoral5840]

Firstly, thank you for tutorial. ı have a question. when you did beam section you wrote TS1=25 and TS2=25 for both rebars. Are these values diameter for rebars? if these values are diameter, longitudinal and transverse rebars diameter have same thickness. This is wrong in civil engineering.Transverse rebars have mostly 10 mm diameter. in this tutorial, did you not care these values.about rebar thickness.

[@dfetech]

Hi Zafer, Firstly, thanks for your comment. We hope this video do provide some help on your activities. TS1 & TS2 are the outer diameters, you also can enter inner diameter in TT1 & TT2. For other settings, please refer to LS-DYNA Manual Volume I. The intension of this video is to guide users how to use S-ALE in LS-DYNA, so we don't actually care the value as long as the model is work, we are able to change it afterward when needed. All the parameter in section/material/EOS are freely to change, as long as the UNIT in LS-DYNA are CONSISTENT. Thank you & wish you a wonderful journey with LS-DYNA.

[@zafertoral5840]

​@@dfetech Hi. ı have a question again :D I did everything how you show like in this tutorial. But, in the RUN ANALYS stage, I having a Error. " Cannot find the executable:mpiexec" writing in the error box. How I overcome this problem. Thank you for supports

[@dfetech]

@@zafertoral5840 Hi Zafer, if you are using LS-DYNA MPP solvers. Please make sure your workstation has correct environment for mpiexec before submit your job. Please contact your local distributor for help. Thank you.

[@lianghuang6095]

so the values of curve 1 are all 0,why?

[@dfetech]

Sorry for the late reply. Please do not follow the materials properties in this video, it is just a sample material. Please use your own concrete materials properties to get the accurate results. You also can use other material models in LS-DYNA like mat084, mat084/085, mat145, etc.

[@shiqizhang3532]

why the refincement has no change 🥲

[@zafertoral5840]

ı did everything like this tutorial and my analysis runded but column or rebar had no deformation. did you solve this poblem?