RC柱单调水平推覆分析问题

westinglie

最近用OpenSEES模拟RC柱的受力分析，低周反复分析出来的滞回曲线不理想，就先做pushover推覆分析，新手，结果还是不行，初始刚度有，但钢筋屈服后突然有个下降突变，屈服后刚度看不出来，跟书上及试验值相差很多。向路过的请教及解决思路！
同时向大家请教，在做RC柱的抗震性能分析时，碰到不收敛的时候，或滞回曲线不好，应该怎么调试参数，使结果好像？
荷载-位移曲线：
tcl命令如下：
#==========================
# 单位制： N，mm
wipe;
model BasicBuilder -ndm 2 -ndf 3;
file mkdir Data;
# ----------------------------------物理本构模型-------------------------------------
set IDConcreteCover 1;
set IDConcreteCore 2;
set IDSteelRein 3;
set IDSteelZeroRein 4;
# 混凝土
set fc -20.1;
set Ec 30000;
# 无约束混凝土
set fc1u $fc;
set eps1u -0.003;
set fc2u [expr 0.2*$fc1u];
set eps2u -0.01;
set lambda 0.1;
set ftu [expr -0.14*$fc1u];
set Ets [expr $ftu/0.002];
uniaxialMaterial Concrete02 $IDConcreteCover $fc1u $eps1u $fc2u $eps2u $lambda $ftu $Ets;
# 约束混凝土
set fc1c [expr 1.3*$fc];
set eps1c [expr 2.*$fc1c/$Ec];
set fc2c [expr 0.2*$fc1c];
set eps2c [expr 5*$eps1c];
set ftc [expr -0.14*$fc1c];
uniaxialMaterial Concrete02 $IDConcreteCore $fc1c $eps1c $fc2c $eps2c $lambda $ftc $Ets;
# 钢筋
# 柱身纵向主筋
set Fy 350;
set Fu [expr 1.2*$Fy];
set Es 200000;
set Esh [expr 0.0255*$Es];
set esh 0.01152;
set eult 0.1105;
uniaxialMaterial ReinforcingSteel $IDSteelRein $Fy $Fu $Es $Esh $esh $eult;
# 零长度单元钢筋
set Sy 0.36;
set Su [expr 30*$Sy];
uniaxialMaterial Bond_SP01 $IDSteelZeroRein $Fy $Sy $Fu $Su 0.4 0.6;
# -------------------------------------------------------------------------------------------
# ---------------------------------------几何模型---------------------------------------------
set LCol 1175;
set PCol 250000;
set HSec 250;
set BSec 250;
set coverH 20;
set coverB 20;
set DSteel 14;
set ASteel [expr 3.14*pow($DSteel/2,2)];
node 1 0 0;
node 2 0 $LCol;
node 1000 0 0;
set IDColSec 1;
set IDZeroSec 2;
set IDnonlinearBeamColumnele 3;
set IDzerolengthSecele 4;
# 纤维截面模型
set coverY [expr $HSec/2];
set coverZ [expr $BSec/2];
set coreY [expr $coverY-$coverH];
set coreZ [expr $coverZ-$coverB];
set nfY 16;
set nfZ 4;
# 柱身单元纤维截面
section fiberSec $IDColSec {
       patch quadr $IDConcreteCore $nfZ $nfY -$coreY $coreZ -$coreY -$coreZ $coreY -$coreZ $coreY $coreZ;
      patch quadr $IDConcreteCover 1 $nfY -$coverY $coverZ -$coreY $coreZ $coreY $coreZ $coverY $coverZ;
patch quadr $IDConcreteCover 1 $nfY -$coreY -$coreZ -$coverY -$coverZ $coverY -$coverZ $coreY -$coreZ;
patch quadr $IDConcreteCover $nfZ 1 -$coverY $coverZ -$coverY -$coverZ -$coreY -$coreZ -$coreY $coreZ;
patch quadr $IDConcreteCover $nfZ 1 $coreY $coreZ $coreY -$coreZ $coverY -$coverZ $coverY $coverZ;
layer straight $IDSteelRein 3 $ASteel -$coreY $coreZ -$coreY -$coreZ;
layer straight $IDSteelRein 3 $ASteel  $coreY $coreZ  $coreY -$coreZ;
};
# 零长度单元纤维截面
section fiberSec $IDZeroSec {
patch quadr $IDConcreteCore $nfZ $nfY -$coreY $coreZ -$coreY -$coreZ $coreY -$coreZ $coreY $coreZ;
      patch quadr $IDConcreteCover 1 $nfY -$coverY $coverZ -$coreY $coreZ $coreY $coreZ $coverY $coverZ;
patch quadr $IDConcreteCover 1 $nfY -$coreY -$coreZ -$coverY -$coverZ $coverY -$coverZ $coreY -$coreZ;
patch quadr $IDConcreteCover $nfZ 1 -$coverY $coverZ -$coverY -$coverZ -$coreY -$coreZ -$coreY $coreZ;
patch quadr $IDConcreteCover $nfZ 1 $coreY $coreZ $coreY -$coreZ $coverY -$coverZ $coverY $coverZ;
layer straight $IDSteelZeroRein 3 $ASteel -$coreY $coreZ -$coreY -$coreZ;
layer straight $IDSteelZeroRein 3 $ASteel  $coreY $coreZ  $coreY -$coreZ;
};
geomTransf PDelta 1;
element nonlinearBeamColumn $IDnonlinearBeamColumnele 1 2 5 $IDColSec 1;
element zeroLengthSection $IDzerolengthSecele 1000 1 $IDZeroSec;
#--------------------------------------------------------------------------------------------
# -----------------------------------边界约束条件---------------------------------------------
fix 1 1 1 0;
fix 1000 1 1 1;
#--------------------------------------------------------------------------------------------
# ------------------------------------数据输出设置--------------------------------------------
recorder Node -file Data/DFree.out -time -node 2 -dof 1 2 3 disp;
recorder Node -file Data/DBase.out -time -node 1 -dof 1 2 3 disp;
recorder Node -file Data/RBase.out -time -node 1 -dof 1 2 3 reaction;
recorder Drift -file Data/Drift.out -time -iNode 2 -jNode 1 -dof 1 -perpDirn 2;
recorder plot Data/Drift.out test 0 0 400 200 -columns 2 1;
#---------------------------------------------------------------------------------------------
puts "Model Built!";                           
#---------------------------------------求解控制-----------------------------------------------
# 轴压比施加
pattern Plain 1 Linear {
       load 2 0 -$PCol 0;
};
constraints Plain;
numberer Plain;
system BandGeneral;
test NormDispIncr 1e-8 6;
algorithm Newton;
integrator LoadControl 0.1;
analysis Static;
analyze 10;
#---------------------------------
puts "Axial-load ratio applied!";
loadConst -time 0.0;
#----------------------------------
# 水平推覆力施加
pattern Plain 2 Linear {
       load 2 $PCol 0 0;
};
constraints Plain;
numberer Plain;
system SparseGeneral -piv;
test NormDispIncr 1e-4 1000;
algorithm KrylovNewton;
analysis Static;
set du1 0.05;
integrator DisplacementControl 2 1 $du1;
analyze 1000;
#===================================================

xutianhang12

为何没人回复

旋风小子

前辈，我正在做型钢混凝土梁柱节点file:///C:\Users\Administrator\AppData\Roaming\Tencent\Users\2292221274\QQ\WinTemp\RichOle\K2A1BX}P25{LL`A$U%){Q8W.png的模拟，不能模拟出下降段，请问一下是什么原因？