求整体刚度矩阵matlab程序

1、精选优质文档-倾情为你奉上姓名：吴佳侣班级：机自11-13学号：例： 如图所示有限元模型，弹性模量为 ，厚度为 ，为简化计算取 ，求整体刚度矩阵。部分分析思路：各单元信息单元编号整体编码1,2,32,4,55,3,23,5,6局部编码以整编码体表示的单元刚度矩阵整体刚度矩阵程序：%求整体刚度矩阵clcclear allsyms E u t a%定义变量%写出单元刚度矩阵,单元面积为a2/2%单元1bi=0;ci=a;bj=-a;cj=-a;bm=a;cm=0;mianji=a2/2;B1=1/2/mianji*bi 0 bj 0 bm 0 0 ci 0 cj 0 cm ci bi cj bj

2、cm bm;u=0;E=1;t=1; D=E/(1-u2)*1 u 0 u 1 0 0 0 (1-u)/2; %弹性矩阵D k1=transpose(B1)*D*B1*t*mianji;%单元2bi=0;ci=a;bj=-a;cj=a;bm=a;cm=0;mianji=a2/2;B2=1/2/mianji*bi 0 bj 0 bm 0 0 ci 0 cj 0 cm ci bi cj bj cm bm;u=0;E=1;t=1; D=E/(1-u2)*1 u 0 u 1 0 0 0 (1-u)/2; %弹性矩阵D K3=transpose(B2)*D*B2*t*mianji;%单元3bi=0;ci

3、=-a;bj=a;cj=-a;bm=-a;cm=0;mianji=a2/2;B3=1/2/mianji*bi 0 bj 0 bm 0 0 ci 0 cj 0 cm ci bi cj bj cm bm;u=0;E=1;t=1; D=E/(1-u2)*1 u 0 u 1 0 0 0 (1-u)/2; %弹性矩阵D k2=transpose(B3)*D*B3*t*mianji;%单元4bi=0;ci=a;bj=-a;cj=-a;bm=a;cm=0;mianji=a2/2;B4=1/2/mianji*bi 0 bj 0 bm 0 0 ci 0 cj 0 cm ci bi cj bj cm bm;u=0

4、;E=1;t=1; D=E/(1-u2)*1 u 0 u 1 0 0 0 (1-u)/2; %弹性矩阵D K4=transpose(B4)*D*B4*t*mianji;% %单元刚度矩阵再分解k1_11=k1(1:2,1:2);k1_12=k1(1:2,3:4);k1_13=k1(1:2,5:6);k1_21=k1(3:4,1:2);k1_22=k1(3:4,3:4); k1_23=k1(3:4,5:6);k1_31=k1(5:6,1:2);k1_32=k1(5:6,3:4); k1_33=k1(5:6,5:6); % %k2_22=k2(1:2,1:2);k2_24=k2(1:2,3:4);

5、k2_25=k2(1:2,5:6);k2_42=k2(3:4,1:2);k2_44=k2(3:4,3:4); k2_45=k2(3:4,5:6);k2_52=k2(5:6,1:2);k2_54=k2(5:6,3:4); k2_55=k2(5:6,5:6); % %k3_55=k2(1:2,1:2);k3_53=k2(1:2,3:4);k3_52=k2(1:2,5:6);k3_35=k2(3:4,1:2);k3_33=k2(3:4,3:4); k3_32=k2(3:4,5:6);k3_25=k2(5:6,1:2);k3_23=k2(5:6,3:4); k3_22=k2(5:6,5:6);% %k

6、4_33=k2(1:2,1:2);k4_35=k2(1:2,3:4);k4_36=k2(1:2,5:6);k4_53=k2(3:4,1:2);k4_55=k2(3:4,3:4); k4_56=k2(3:4,5:6);k4_63=k2(5:6,1:2);k4_65=k2(5:6,3:4); k4_66=k2(5:6,5:6);%单元刚度矩阵组装，形成整体刚度矩阵%k_11=k1_11; k_12=k1_12; k_13=k1_13; k_14=zeros(2,2); k_15=zeros(2,2); k_16=zeros(2,2); k_21=k1_21; k_22=k1_22+k2_22+k3

7、_22; k_23=k1_23+k3_23; k_24=k2_24; k_25=k2_25+k3_25; k_26=zeros(2,2); k_31=k1_31; k_32= k1_32+k3_32; k_33=k1_33+k3_33+k4_33; k_34=zeros(2,2); k_35=k3_35+k4_35;k_36= k4_36; k_41=zeros(2,2); k_42=k2_42; k_43=zeros(2,2); k_44=k2_44; k_45=k2_45; k_46=zeros(2,2); k_51=zeros(2,2); k_52=k2_52+k3_52;k_53=k3_53+k4_53; k_54=k2_54; k_55=k2_55+k3_55+k4_55; k_56=k4_56;k_61=zeros(2,2); k_62=zeros(2,2); k_63=k4_63; k_64=zeros(2,2); k_65=k4_65;k_66=k4_66;% k=k_11 k_12 k_13 k_14 k_15 k_16; k_21 k_22 k_23 k_24 k_25 k_26; k_31 k_32 k_33 k_34 k_35 k_36;