Question

IK] is a 'hypothetical element stiffness matrix, fill ght be multiple correct answers. Report one correct 2) If a, b, c, d are positive numbers and [K] is a 'h he missing elements. (Note: there might be multi answer) S 1 b a [K]=/0 I T 26 Lu

Answer 1

& The riven stiffness matrix is 5x5. general 5x5 matrin is shown below to The given stiffness m general 5x5 matri [ Kil Kiz Kez Kin Kis ko | Kai Kiz Kas kay Kas Koi Koz IC33 Kay Kui Kuz Kya Kay Ksi Ksz ks O - lo b. F. - a T- U - B Comparing ① and ② , we get Kiz=N, kiy=s, kaz=b, k23=F, kas=0 K3 =D , K3= a , K3y = T, Ky2 = 0 , Kyy = 2b Kus=A, Ks1 = U, K53 =B we know that stiffness matrix is always symetrical K12 = Kzn = N Kps = Ks3 = B K3 = k 31 =D Kay = Ky2 = 0 ks2 = kas = 0 kly = ky = S ksy = Kys = A. *32 Kz3 = F Kyz= Katy = T Kis = ksi =U ! 1

we know that, jonal positive Kil = any positive nung the elements of stiffness matrix are alway •kil = any positive number (a or borcord) 2 kss = any positive number ( 4 ) Therefore, From ①, we have T Take kil = a e Kss=b K = reno z a N IN b. р ғ o 0 sota *