git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@10431 f3b2605a-c512-4ea7-a41b-209d697bcdaa

doc/pair_peri.html

@@ -17,11 +17,13 @@
 </H3>
 <H3>pair_style peri/lps/omp command 
 </H3>
+<H3>pair_style peri/ves command 
+</H3>
 <P><B>Syntax:</B>
 </P>
 <PRE>pair_style style 
 </PRE>
-<UL><LI>style = <I>peri/pmb</I> or <I>peri/lps</I> 
+<UL><LI>style = <I>peri/pmb</I> or <I>peri/lps</I> or <I>peri/ves</I> 
 </UL>
 <P><B>Examples:</B>
 </P>
@@ -31,6 +33,9 @@ pair_coeff * * 1.6863e22 0.0015001 0.0005 0.25
 <PRE>pair_style peri/lps
 pair_coeff * * 14.9e9 14.9e9 0.0015001 0.0005 0.25 
 </PRE>
+<PRE>pair_style peri/ves
+pair_coeff * * 14.9e9 14.9e9 0.0015001 0.0005 0.25 0.5 0.001 
+</PRE>
 <P><B>Description:</B>
 </P>
 <P>The peridynamic pair styles implement material models that can be used
@@ -42,12 +47,21 @@ microelastic brittle (PMB) model.
 <P>Style <I>peri/lps</I> implements the Peridynamic state-based linear
 peridynamic solid (LPS) model.
 </P>
+<P>Style <I>peri/ves</I> implements the Peridynamic state-based linear
+peridynamic viscoelastic solid (VES) model.
+</P>
 <P>The canonical papers on Peridynamics are <A HREF = "#Silling2000">(Silling 2000)</A>
 and <A HREF = "#Silling2007">(Silling 2007)</A>.  The implementation of Peridynamics
 in LAMMPS is described in <A HREF = "#Parks">(Parks)</A>.  Also see the <A HREF = "http://www.sandia.gov/~mlparks/papers/PDLAMMPS.pdf">PDLAMMPS
 user guide</A> for
 more details about the implementation of peridynamics in LAMMPS.
 </P>
+<P>The peridynamic VES model in PDLAMMPS is implemented by R. Rahman and
+J.T Foster at University of Texas at San Antonio. The VES formulation
+is described in "(Mtchell2011)". For question regarding VES
+implementation in LAMMPS please contact R.Rahman:
+rezwanur.rahman@utsa.edu
+</P>
 <P>The following coefficients must be defined for each pair of atom types
 via the <A HREF = "pair_coeff.html">pair_coeff</A> command as in the examples above,
 or in the data file or restart files read by the
@@ -81,6 +95,25 @@ cutoff distance for truncating interactions, and s00 and alpha are
 used as a bond breaking criteria. See the users guide for more
 details.
 </P>
+<P>For the <I>peri/ves</I> style:
+</P>
+<UL><LI>K (force/area units)
+<LI>G (force/area units)
+<LI>horizon (distance units)
+<LI>s00 (unitless)
+<LI>alpha (unitless) 
+<LI>m_lambdai (unitless)
+<LI>m_taubi (unitless) 
+</UL>
+<P>The same as for <I>peri/lps</I>, K is the bulk modulus and G is the shear
+modulus. The horizon is a cutoff distance for truncating interactions,
+and s00 and alpha are used as a bond breaking criteria. m_lambdai and
+m_taubi are the viscoelastic relaxation parameter and time constant,
+respectively. m_lambdai varies within zero to one. For very small
+values of m_lambdai the viscoelsatic model responds very similar to a
+linear elastic model. For details see the description in
+<A HREF = "#Mitchell">(Mitchell)</A>.
+</P>
 <HR>
 
 <P>Styles with a <I>cuda</I>, <I>gpu</I>, <I>omp</I>, or <I>opt</I> suffix are functionally
@@ -128,7 +161,7 @@ to be specified in an input script that reads a restart file.
 
 <P><B>Restrictions:</B>
 </P>
-<P>The <I>peri/pmb</I> and <I>peri/lps</I> styles are part of the PERI
+<P>The <I>peri/pmb</I>, <I>peri/lps</I> and <I>peri/ves</I> styles are part of the PERI
 package. They are only enabled if LAMMPS was built with that package.
 See the <A HREF = "Section_start.html#start_3">Making LAMMPS</A> section for more
 info.
@@ -143,7 +176,8 @@ info.
 
 <A NAME = "Parks"></A>
 
-<P><B>(Parks)</B> Parks, Lehoucq, Plimpton, Silling, Comp Phys Comm, 179(11), 777-783 (2008).
+<P><B>(Parks)</B> Parks, Lehoucq, Plimpton, Silling, Comp Phys Comm, 179(11),
+777-783 (2008).
 </P>
 <A NAME = "Silling2000"></A>
 
@@ -151,6 +185,13 @@ info.
 </P>
 <A NAME = "Silling2007"></A>
 
-<P><B>(Silling 2007)</B> Silling, Epton, Weckner, Xu, Askari, J Elasticity, 88, 151-184 (2007).
+<P><B>(Silling 2007)</B> Silling, Epton, Weckner, Xu, Askari, J Elasticity,
+88, 151-184 (2007).
+</P>
+<A NAME = "Mitchell"></A>
+
+<P><B>(Mitchell)</B> Mitchell, "A non-local, ordinary-state-based
+viscoelasticity model for peridynamics", Sandia National Lab Report,
+8064:1-28 (2011).
 </P>
 </HTML>

doc/pair_peri.txt

@@ -10,12 +10,13 @@ pair_style peri/pmb command :h3
 pair_style peri/pmb/omp command :h3
 pair_style peri/lps command :h3
 pair_style peri/lps/omp command :h3
+pair_style peri/ves command :h3
 
 [Syntax:]
 
 pair_style style :pre 
 
-style = {peri/pmb} or {peri/lps} :ul
+style = {peri/pmb} or {peri/lps} or {peri/ves} :ul
 
 [Examples:]
 
@@ -25,6 +26,9 @@ pair_coeff * * 1.6863e22 0.0015001 0.0005 0.25 :pre
 pair_style peri/lps
 pair_coeff * * 14.9e9 14.9e9 0.0015001 0.0005 0.25 :pre
 
+pair_style peri/ves
+pair_coeff * * 14.9e9 14.9e9 0.0015001 0.0005 0.25 0.5 0.001 :pre
+
 [Description:]
 
 The peridynamic pair styles implement material models that can be used
@@ -36,12 +40,21 @@ microelastic brittle (PMB) model.
 Style {peri/lps} implements the Peridynamic state-based linear
 peridynamic solid (LPS) model.
 
+Style {peri/ves} implements the Peridynamic state-based linear
+peridynamic viscoelastic solid (VES) model.
+
 The canonical papers on Peridynamics are "(Silling 2000)"_#Silling2000
 and "(Silling 2007)"_#Silling2007.  The implementation of Peridynamics
 in LAMMPS is described in "(Parks)"_#Parks.  Also see the "PDLAMMPS
 user guide"_http://www.sandia.gov/~mlparks/papers/PDLAMMPS.pdf for
 more details about the implementation of peridynamics in LAMMPS.
 
+The peridynamic VES model in PDLAMMPS is implemented by R. Rahman and
+J.T Foster at University of Texas at San Antonio. The VES formulation
+is described in "(Mtchell2011)". For question regarding VES
+implementation in LAMMPS please contact R.Rahman:
+rezwanur.rahman@utsa.edu
+
 The following coefficients must be defined for each pair of atom types
 via the "pair_coeff"_pair_coeff.html command as in the examples above,
 or in the data file or restart files read by the
@@ -75,6 +88,25 @@ cutoff distance for truncating interactions, and s00 and alpha are
 used as a bond breaking criteria. See the users guide for more
 details.
 
+For the {peri/ves} style:
+
+K (force/area units)
+G (force/area units)
+horizon (distance units)
+s00 (unitless)
+alpha (unitless) 
+m_lambdai (unitless)
+m_taubi (unitless) :ul
+
+The same as for {peri/lps}, K is the bulk modulus and G is the shear
+modulus. The horizon is a cutoff distance for truncating interactions,
+and s00 and alpha are used as a bond breaking criteria. m_lambdai and
+m_taubi are the viscoelastic relaxation parameter and time constant,
+respectively. m_lambdai varies within zero to one. For very small
+values of m_lambdai the viscoelsatic model responds very similar to a
+linear elastic model. For details see the description in
+"(Mitchell)"_#Mitchell.
+
 :line
 
 Styles with a {cuda}, {gpu}, {omp}, or {opt} suffix are functionally
@@ -122,7 +154,7 @@ These pair styles can only be used via the {pair} keyword of the
 
 [Restrictions:]
 
-The {peri/pmb} and {peri/lps} styles are part of the PERI
+The {peri/pmb}, {peri/lps} and {peri/ves} styles are part of the PERI
 package. They are only enabled if LAMMPS was built with that package.
 See the "Making LAMMPS"_Section_start.html#start_3 section for more
 info.
@@ -136,10 +168,17 @@ info.
 :line
 
 :link(Parks)
-[(Parks)] Parks, Lehoucq, Plimpton, Silling, Comp Phys Comm, 179(11), 777-783 (2008).
+[(Parks)] Parks, Lehoucq, Plimpton, Silling, Comp Phys Comm, 179(11),
+777-783 (2008).
 
 :link(Silling2000)
 [(Silling 2000)] Silling, J Mech Phys Solids, 48, 175-209 (2000).
 
 :link(Silling2007)
-[(Silling 2007)] Silling, Epton, Weckner, Xu, Askari, J Elasticity, 88, 151-184 (2007).
+[(Silling 2007)] Silling, Epton, Weckner, Xu, Askari, J Elasticity,
+88, 151-184 (2007).
+
+:link(Mitchell)
+[(Mitchell)] Mitchell, "A non-local, ordinary-state-based
+viscoelasticity model for peridynamics", Sandia National Lab Report,
+8064:1-28 (2011).