Hello Abaqus users,
My model and elastic model which is divided into 10 steps, i checked the results, i found something strange. from step #1 to step#4 every thing looks good, i.e., the number of increments shown in the job module>> monitor are the same as that shown in the viewer. for step #5...
I am working on Rock, The rock is similar to concrete in its behavior, usually it is brittle or quasi-brittle.
I know that the softening of material can be simulated in the elastic-plastic criterion. I asked my self, what is the difference between concrete damage plasticity and elastic-plastic...
Hello
I need to know what is the difference between modeling a material for instance concrete as elastic-plastic with strain softening and model the same material (concrete) using damage plasticity approach.
Although In elastic-plastic with strain softening, the post peak failure is included...
Thanks MechIrl,
although the first part of the stress strain curve is linear, but it does not represent an elastic behavior, i just assume that the first part is elastic so i can use elastic-plastic criterion in Abaqus.
This stress-strain curve represents the compaction of rock cuttings, so as...
Thanks Sdebock for your comment, and sorry about not mentioning that i am using linear Drucker prager plasticity model.
the Data that i sent before in the excel sheet is a published paper. and many people use it to calibrate their model, because it is very reliable.
So let me clear this time...
I used the following equation to convert the true strain to true plastic strain which should be used in Abaqus.
e(plastic strain)=e(true strain)-(true stress/Young's Modulus).
If you use this equation, you will find that the equivalent plastic strain will be negative
for example:
e(plastic...
Hello,
First of all, sorry about all numbers after decimal places, i just cut the numbers from the excel sheet.
I am not using metal plasticity, i am using Drucker Prager plasticity because i am working on rock not metal. In Drucker prager i need to define the yield stress as function of the...
I am posting the first and the second tables again because i noticed they are not clear. this table represents the stress-strain curve.
Stress strain
0 0
143.4108527 0.1
405.1094891 0.2
637.9310345 0.25
768.8558235 0.27
1034.161491 0.3
1149.298597 0.31
1485...
Hello
I am working on a material whose stress strain curve is strain hardening (concave upward), unlike the steel whose strain harening is concave downward.
the problem is when i calculate the equivalent plastic strain, it is negative. the following table represents the true stress-strain...
Hello
For Elastic-perfect plastic material or strain softening material, I notice that if i apply load more than the yield limit, the model diverges, while when i apply load through displacement control, the model converges, although the displacement is big.
So my question is why load control...
Hello everyone,
I wish someone help me to understand how to apply the softening behavior of rock in Mohr-coulomb.
I know the friction angle and cohesion of the rock sample from the shear test. Moreover, i have the stress-strain curve for the rock (Uniaxial compression test).
the rock sample...
Hello everyone,
I have three viewports in ABAQUS viewer, i need to compare them.
The problem is:
the same color has different range of values for different viewports, for instance in the first viewport, the red color represents a stress ranges from 1000-1100, while in the second viewport, the...
Thank you very much Portilner,
My Global model is subjected to Kinds of loads, the first load is Uniformely distributed loads on the top surface of the model, the second load is Gravity load.
So, you advice me to apply all kinds of loads to the submodel. Right? Hence i should apply both...
Hello everyone,
I am confused about Applying the loads and the Boundary conditions to the submodel,
Regarding the loads, there was a uniform distributed load on the global model, so shall i apply this load again on the submodel? or it will automatically transferred to the submodel through the...
Hello there,
I have used a simple model to understand sub-modeling technique, but i failed, and i need your help.
The model is 3D model (block). A uniform distributed load was applied on the top surface of the block, the bottom surface of the block is fixed in all directions, while the edges...
The input file for the submodel is here.
Please help me if you know how to do submodel http://files.engineering.com/getfile.aspx?folder=af66bc61-f335-4fcc-a15c-aa4e975e4f44&file=sub-trial.inp
Hello everyone,
since my original model is complex, so i have made a small 3D-model to study how to make submode, but unfortunately i could not.
This model is 3D block under compression, the base is fixed, i remove some elements at the middle of the block. I want to make submodel to focuss...
Hello there,
I am modelling an underground mine, I remove some elements to simulate excavations. After removing these elements, I have pillars (similar to columns in surface buildings), these pillars support the overburden rocks. the rock layer underneath the pillars is called the floor, while...
Hello,
To define the hardening or softening of a material using Mohr-Coulomb criterion, i need to define the variation of cohesion yield stress with Abs. plastic strain.
The question is, how can i define the variation of the cohesion yield stress with plastic strain? I know that, i can find...
