cat << EOT > awk_ss.awk
BEGIN{
    fcu=35
    rm=1.5
    cu=0.67*fcu/rm
    ey=0.00024*sqrt(fcu/rm)
    dx=0.00005
    eu=0.0035
    nn=eu/dx
    for(i=0;i<=nn;i++){
        xx=i*dx
        sig=-cu/ey/ey*(xx-ey)**2+cu
        if(ey<=xx)sig=cu
        print xx,sig
    }
}
EOT
awk -f awk_ss.awk > _ss.txt

fig=fig_gmt_ss_con.eps
gmt set FONT_LABEL 20p
gmt set MAP_TICK_LENGTH_PRIMARY -0.1c
gmt psxy _ss.txt -R0/0.0040/0/18 -JX15/10 -W2 -Bxf0.0035+l'Strain' -Byf15.633+l'Stress' -BSW -P -K > $fig
gmt pstext -R -J -F+f+a+j -N -O -K << EOT >> $fig
0.0012093 2 16p 90 LT 0.00024(f@-cu@-/@~g@~@-m@-)@+1/2@+
0.0035500 2 16p 90 LT 0.0035
0.0002 16.133 16p 0 LB 0.67 f@-cu@-/@~g@~@-m@-
0.0001 0.5 16p 0 LB 5.5(f@-cu@-/@~g@~@-m@-)@+1/2@+
0.0001 1.5 16p 0 LB Initial gradient
EOT
echo '0 15.633 0.0011593 15.633' | gmt psxy -R -J -Sv0.05+s -W0.75,#777777,3_3:0 -O -K >> $fig
echo '0.0011593 0 0.0011593 15.633' | gmt psxy -R -J -Sv0.05+s -W0.75,#777777,3_3:0 -O -K >> $fig
echo '0.0035000 0 0.0035000 15.633' | gmt psxy -R -J -Sv0.05+s -W0.75,#777777,3_3:0 -O >> $fig


fig=fig_gmt_ss_steel.eps
gmt set FONT_LABEL 20p
gmt set MAP_TICK_LENGTH_PRIMARY -0.1c
gmt psxy -R-0.0080/0.0080/-550/550 -JX15/10 -W2 -P -K << EOT > $fig
-0.0070 -460
-0.0023 -460
 0.0023  460
 0.0070  460
EOT
gmt pstext -R -J -F+f+a+j -N -O -K << EOT >> $fig
 0.0040  -10 20p  0 CT Strain
-0.0002  250 20p 90 CB Stress
 0.0050  480 16p  0 CB Tension
-0.0050 -480 16p  0 CT Compression
-0.0001  460 16p  0 RM f@-y@-/@~g@~@-m@-
 0.0001 -460 16p  0 LM f@-y@-/@~g@~@-m@-
 0.0006   60 16p 61 LT 200kN/mm@+2@+
EOT
echo '-0.0080 0 0.0080 0'  | gmt psxy -R -J -Sv0.05+s -W0.75,#000000 -O -K >> $fig
echo '0 -550 0 550'        | gmt psxy -R -J -Sv0.05+s -W0.75,#000000 -O -K >> $fig
echo '0  460  0.0023  460' | gmt psxy -R -J -Sv0.05+s -W0.75,#777777,3_3:0 -O -K >> $fig
echo '0 -460 -0.0023 -460' | gmt psxy -R -J -Sv0.05+s -W0.75,#777777,3_3:0 -O >> $fig