%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %pingetensor syms x y z S=[3*x*y 5*y^2 0; 5*y^2 0 2*z; 0 2*z 0] S = [ 3*x*y, 5*y^2, 0] [ 5*y^2, 0, 2*z] [ 0, 2*z, 0] %silinder y^2+z^2-4=0 phi= y^2+z^2-4 phi = y^2+z^2-4 % SILINDRI KÜLGPIND % pinnanormaal: nu=[diff(phi,x),diff(phi,y),diff(phi,z)] nu = [ 0, 2*y, 2*z] %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt P x=2,y=1,z=sqrt(3) x = 2 y = 1 z = 1.7321 % pingetensor SP=subs(S), SP = 6.0000 5.0000 0 5.0000 0 3.4641 0 3.4641 0 % pinnanormaal nuP=subs(nu), nuP = 0 2.0000 3.4641 % ühiknormaal nuP=nuP/norm(nuP) nuP = 0 0.5000 0.8660 % pingevektor p=(nuP*SP) p = 2.5000 3.0000 1.7321 % pingevektori moodul pm=norm(p) pm = 4.2720 % pingevektori proj. normaalil sigma=p*nuP' sigma = 3.0000 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 3.0414 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 0.8220 0.4932 -0.2847 % nihkepinge vektor tauv=tau*tv tauv = 2.5000 1.5000 -0.8660 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt Q x=0,y=1,z=sqrt(3) x = 0 y = 1 z = 1.7321 % pingetensor SP=subs(S), SP = 0 5.0000 0 5.0000 0 3.4641 0 3.4641 0 % pinnanormaal nuP=subs(nu), nuP = 0 2.0000 3.4641 % ühiknormaal nuP=nuP/norm(nuP) nuP = 0 0.5000 0.8660 % pingevektor p=(nuP*SP) p = 2.5000 3.0000 1.7321 % pingevektori moodul pm=norm(p) pm = 4.2720 % pingevektori proj. normaalil sigma=p*nuP' sigma = 3.0000 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 3.0414 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 0.8220 0.4932 -0.2847 % nihkepinge vektor tauv=tau*tv tauv = 2.5000 1.5000 -0.8660 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt R x=4,y=1,z=sqrt(3) x = 4 y = 1 z = 1.7321 % pingetensor SP=subs(S), SP = 12.0000 5.0000 0 5.0000 0 3.4641 0 3.4641 0 % pinnanormaal nuP=subs(nu), nuP = 0 2.0000 3.4641 % ühiknormaal nuP=nuP/norm(nuP) nuP = 0 0.5000 0.8660 % pingevektor p=(nuP*SP) p = 2.5000 3.0000 1.7321 % pingevektori moodul pm=norm(p) pm = 4.2720 % pingevektori proj. normaalil sigma=p*nuP' sigma = 3.0000 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 3.0414 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 0.8220 0.4932 -0.2847 % nihkepinge vektor tauv=tau*tv tauv = 2.5000 1.5000 -0.8660 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt L x=2,y=2,z=0 x = 2 y = 2 z = 0 % pingetensor SP=subs(S), SP = 12 20 0 20 0 0 0 0 0 % pinnanormaal nuP=subs(nu), nuP = 0 4 0 % ühiknormaal nuP=nuP/norm(nuP) nuP = 0 1 0 % pingevektor p=(nuP*SP) p = 20 0 0 % pingevektori moodul pm=norm(p) pm = 20 % pingevektori proj. normaalil sigma=p*nuP' sigma = 0 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 20 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 1 0 0 % nihkepinge vektor tauv=tau*tv tauv = 20 0 0 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt M x=2,y=0,z=2 x = 2 y = 0 z = 2 % pingetensor SP=subs(S), SP = 0 0 0 0 0 4 0 4 0 % pinnanormaal nuP=subs(nu), nuP = 0 0 4 % ühiknormaal nuP=nuP/norm(nuP) nuP = 0 0 1 % pingevektor p=(nuP*SP) p = 0 4 0 % pingevektori moodul pm=norm(p) pm = 4 % pingevektori proj. normaalil sigma=p*nuP' sigma = 0 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 4 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 0 1 0 % nihkepinge vektor tauv=tau*tv tauv = 0 4 0 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % OTSPIND x=0 % otspinna ühiknormaal nuP=[-1,0,0] nuP = -1 0 0 % pinge melevaldses punktis pmp=(nuP*S).' pmp = [ -3*x*y] [ -5*y^2] [ 0] %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt Q x=0,y=1,z=sqrt(3) x = 0 y = 1 z = 1.7321 % pingetensor SP=subs(S), SP = 0 5.0000 0 5.0000 0 3.4641 0 3.4641 0 % pingevektor p=(nuP*SP) p = 0 -5 0 % pingevektori moodul pm=norm(p) pm = 5 % pingevektori proj. normaalil sigma=p*nuP' sigma = 0 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 5 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 0 -1 0 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % OTSPIND x=4 % otspinna ühiknormaal nuP=[1,0,0] nuP = 1 0 0 % pinge melevaldses punktis pmp=(nuP*S).' pmp = [ 3*x*y] [ 5*y^2] [ 0] %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Punkt P x=4,y=1,z=sqrt(3) x = 4 y = 1 z = 1.7321 % pingetensor SP=subs(S), SP = 12.0000 5.0000 0 5.0000 0 3.4641 0 3.4641 0 % pingevektor p=(nuP*SP) p = 12 5 0 % pingevektori moodul pm=norm(p) pm = 13 % pingevektori proj. normaalil sigma=p*nuP' sigma = 12 % nihkepinge moodul tau = sqrt(pm^2-sigma^2) tau = 5 % nihkepinge sihiline ühikvektor nuPp=cross(nuP,p); tv=cross(nuPp,nuP)/norm(nuPp) tv = 0 1 0 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %Pinge silindrilise pinna meelevaldses punktis syms x y z % 1. sil. pinna normaal nu nu = [ 0, 2*y, 2*z] % 2. sil. pinna ühiknormaal nuno=sqrt(4*y^2+4*z^2) nuno = 2*(y^2+z^2)^(1/2) nuy=nu/nuno nuy = [ 0, y/(y^2+z^2)^(1/2), z/(y^2+z^2)^(1/2)] % pinge meelevaldses punktis pmp=((nuy*S).') pmp = [ 5*y^3/(y^2+z^2)^(1/2)] [ 2*z^2/(y^2+z^2)^(1/2)] [ 2*y/(y^2+z^2)^(1/2)*z] echo off