6.1.1 Tension Cut-off

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Subsections

6.1.1.1 Ambient Influence

6.1.1 Tension Cut-off

There are two tension cut-off criteria available: constant and linear [Fig.6.1].

**Figure 6.1:** Tension cut-off in two-dimensional principal stress space
$\begin{figure}\begin{footnotesize}\setlength{\unitlength}{1cm} \begin{picture... ...enterline{\raise 3.6cm\box\graph} } \end{picture}\end{footnotesize} \end{figure}$

Constant stress cut-off (syntax)

$\begin{figure}\centering \begin{tabbing} \texttt{'MATERI'} \\ [-1.0ex] \rule{14... ... \>\>\texttt{CRKVAL}\>\texttt{\textit{ft}}$_{r}\,$ \end{tabbing} \end{figure}$

CRACK: 1 indicates constant stress cut-off: a crack arises if the major principal tensile stress exceeds f_t .
CRKVAL: ft is the tensile strength f_t .

Linear stress cut-off (syntax)

$\begin{figure}\centering \begin{tabbing} \texttt{'MATERI'} \\ [-1.0ex] \rule{14... ...\textit{ft}}$_{r}\,$ \texttt{\textit{fc}}$_{r}\,$ \end{tabbing} \end{figure}$

CRACK: 2 indicates linear stress cut-off: a crack arises if the major principal tensile stress exceeds the minimum of f_t and f_t(1 + $\sigma_{{\mathrm{lateral}}}^{}$ /f_c) , with $\sigma_{{\mathrm{lateral}}}^{}$ the lateral principal stress.
CRKVAL: ft is the tensile strength f_t , fc is the compressive strength f_c .

6.1.1.1 Ambient Influence

The tension cut-off criterion may be specified depending on ambient values for temperature, concentration or maturity. In this case the criterion must be specified with CRACK as indicated in the previous section followed by the data records in this section. It is not necessary to specify the constant values with CRKVAL.

Constant stress cut-off (syntax)

$\begin{figure}\centering \begin{tabbing} \texttt{'MATERI'} \\ [-1.0ex] \rule{14... ...extit{mvz}}$_{r}\,$ \texttt{\textit{ftz}}$_{r}\,$ \end{tabbing} \end{figure}$

fta ...ftz: are the tensile strengths f_t , (z $\leq$ 30 )respectively valid for the corresponding ambient values.
TEMCRK: specifies temperature influence, tea ...tez are temperatures T .
CONCRK: specifies concentration influence, coa ...coz are concentrations C .
MATCRK: specifies maturity influence, mva ...mvz are maturity variables.

Linear stress cut-off (syntax)

$\begin{figure}\centering \begin{tabbing} \texttt{'MATERI'} \\ [-1.0ex] \rule{14... ...extit{ftz}}$_{r}\,$ \texttt{\textit{fcz}}$_{r}\,$ \end{tabbing} \end{figure}$

fta ...ftz: (z $\leq$ 30 )are the tensile strengths f_t , respectively valid for the corresponding ambient values.
fca ...fcz: are the compressive strengths f_c , respectively valid for the corresponding ambient values.
TEMCRK: specifies temperature influence, tea ...tez are temperatures T .
CONCRK: specifies concentration influence, coa ...coz are concentrations C .
MATCRK: specifies maturity influence, mva ...mvz are maturity variables M .

(file.dat)

'MATERI'
  1   CRACK  1
      MATCRK   0.0  0.01
               1.0  3.0

User-supplied (syntax)

$\begin{figure}\centering \begin{tabbing} \texttt{'MATERI'} \\ [-1.0ex] \rule{14... ...\>\texttt{USRCRK}\>\texttt{\textit{usrkey}}$_{w}\,$ \end{tabbing} \end{figure}$

USRCRK: specifies that the ambient influence on the tension cut-off model is determined via a user-supplied subroutine [§11.3.2]. DIANA passes the keyword usrkey to the first argument of this subroutine.

Next: 6.1.2 Tension Softening Up: 6.1 Smeared Cracking Previous: 6.1 Smeared Cracking Contents Index

DIANA-9.3 User's Manual - Material Library
First ed.

Copyright (c) 2008 by TNO DIANA BV.