Single element simulation on K&C and CSCM
Sophie Clark
l...@schwer.net
Hello Sophia –
Both MAT072R3 (K&C) and MAT159 (CSCM) use quite different models for strain softening, so there is no reason to assume the softening stress strain response would be the same.
If you had some laboratory softening characterization data, you could theoretically tune either model to such data.
--len
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Sophie Clark
l...@schwer.net
Sophie –
Both models make use of the CEB specific fracture energy based on unconfined compressive strength and maximum aggregate size.
The K&C model is based on MAT016 (*MAT_PSEUDO_TENSOR) so have a look in the User Manual Volume II at that model description of damage (strain softening). There is a “damage” surface that the stress trajectory migrates to after reaching the maximum shear failure surface based on accumulation of effective plastic strain.
The CSCM damage formulation, two modes, is fairly well described in the User Manual Volume II. The damage is based on the strain energy.
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James M. Kennedy
Dear Sophie,
See if these presentations are of some help:
LS-DYNA software has several advanced constitutive models developed to simulate concrete material behavior, the most usual ones are *MAT_016, *MAT_072R3, *MAT_084, and *MAT_159. Most of these have automatic generation capability of concrete law parameters. LS-DYNA is able to provide, starting from a first reduced set of physical parameters (unconfined compress strength Fc, unconfined tension strength Ft...) a second large set of parameters by internally fitting experimental reference results. A general modeling approach for concrete modeling has been offered, where the main goal was to try and understand the ins and outs of different modeling to be able to have an overall view of a problem:
Van Dorsselaer, N., Lapoujade, V., Nahas, G., Tarallo, F., and Rambach, J.-M., "General Approach for Concrete Modeling: Impact on Reinforced Concrete", 12th International LS-DYNA Users Conference, Dearborn, Michigan, June, 2012.
http://www.dynalook.com/international-conf-2012/blast-impact06-c.pdf
The following study used *MAT_016, *MAT_072R3, and *MAT_159 for comparative concrete material behavior:
Schwer, L.E., "Simple Input Concrete Constitutive Models: An Illustration of Brick Walls & Concrete Cylinder Perforation", 10th International LS-DYNA Users Conference, Dearborn, Michigan, June, 2008.
http://www.dynalook.com/international-conf-2008/PenetrationBlast-4.pdf
Four conventional damage plasticity models for concrete, the Karagozian and Case model (K&C/*MAT_072), the Riedel-Hiermaier-Thoma model (RHT/*MAT_272), the Brannon-Fossum model (BF1), and the Continuous Surface Cap Model (CSCM/*MAT_159) were compared (data included). All four models are essentially isotropic plasticity models for which plasticity is regarded as any form of inelasticity. All of the models support nonlinear elasticity, but with different formulations. All four models employ three shear strength surfaces:
Brannon, R.M., and Leelavanichkul, S., "Survey of Four Damage Models for Concrete", SAN2009-5544, Sandia National Laboratories, Albuquerque, New Mexico, August, 2009.
http://prod.sandia.gov/techlib/access-control.cgi/2009/095544.pdf
https://my.mech.utah.edu/~brannon/pubs/7-2009BrannonLeelavanichkulSurveyConcrete.pdf
This report described a study pertaining to validating the capability afforded by the standard release of the Karagozian & Case (K&C) cementitious (or concrete) material model. In doing this, responses computed with the K&C model for structural components comprised of either concrete or reinforced concrete were compared with results from tests. Comparisons of the responses computed for the structural components were shown for both quasi-static and blast loadings. Computed responses were also compared to data from standard material tests to demonstrate the basic capability afforded by the K&C model. The analytic results shown were computed with the LS-DYNA code. The K&C model is embedded in this code (i.e., Release III, *MAT_072R3 in LS-DYNA) along with the other concrete models considered in this report, *MAT_084 (Winfrith), *MAT_159 (CSCM), and *MAT_272 (RHT):
Crawford, J.E., Wu, Y., Choi, H.-J., Magallanes, J.M., and Lan, S., "Use and Validation of the Release III K&C Concrete Material Model in LS-DYNA", TR-11-36.5, Karagozian and Case Structural Engineers, Burbank, California, July, 2012.
http://www.kcse.com/assets/Uploads/TR-11-36-6-KCCM.pdf
The dynamic analysis code LS-DYNA provides a variety of constitutive models for concrete. The first problem is how to select a proper constitutive model besides the related parameters. The theoretical backgrounds of five simple input concrete models, namely, *MAT_016 (Pseudo Tensor), *MAT_072R3 (K&C), *MAT_084 (Winfrith), *MAT_159 (CSCM) and *MAT_272 (RHT), were reviewed. The basic performances of the five models in capturing the key concrete behaviors, such as axial tension and compression, triaxial isotropic tension and compression, and triaxial shear, were examined through single element simulation:
Xiong, Y.-B., "Applicability Analysis of Simple Input Concrete Models in LS-DYNA", Acto Armamentarii, Vol. 34, pp. 351-357. January, 2013.
Yi, T.J., “Comparative FE Study Between MAT159 and MAT072R3 for Concrete Behaviour Modelling under Quasi-Static Loading in LS-DYNA”, Bachelor’s Thesis, Civil Engineering, Universiti Teknologi Petronkas, Tronoh, January, 2016.
1. Final Dissertation.pdf (utp.edu.my)
Sincerely,
James M. Kennedy
KBS2 Inc.
June 4, 2022
From: ls-d...@googlegroups.com [mailto:ls-d...@googlegroups.com] On Behalf Of Sophie Clark
Sent: Saturday, June 04, 2022 11:33 AM
To: LS-DYNA2 <ls-d...@googlegroups.com>
Subject: [LS-DYNA2] Single element simulation on K&C and CSCM
Dear James and Len
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