void ntTruss::def_BC(){
Kb = K;
int n = nodes.size();
for (int i = 0; i < n; i++){
int bc = nodes.at(i)->get_BC(); //number of bc's at node
BCs += bc; //add boundary conditions to total
///define matrix id for bc's within global K
if (nodes.at(i)->free == false){
int dofX = i * DOF + 0;
int dofY = i * DOF + 1;
int dofZ = i * DOF + 2;
if (nodes.at(i)->fixed == true){
bc_Id.push_back(dofX);
bc_Id.push_back(dofY);
bc_Id.push_back(dofZ);
} else {
if (nodes.at(i)->fixed_X == true){
bc_Id.push_back(dofX);
}
if (nodes.at(i)->fixed_Y == true){
bc_Id.push_back(dofY);
}
if (nodes.at(i)->fixed_Z == true){
bc_Id.push_back(dofZ);
}
}
}
}
////IMPLEMENT BIG SPRING FACTOR
float bsFX = pow(10, 20); // Big Spring Factor
for (int i = 0; i < BCs; i++){
int index = bc_Id.at(i);
Kb(index, index) = Kb(index, index) + bsFX;
F(index, 0) = 0;
}
}
#define sb4(x) (((x) >> 1) ^ (x))
#define sb5(x) (((x) >> 2) ^ (x))
#define rb1(x) SPH_ROTL64(x, 5)
#define rb2(x) SPH_ROTL64(x, 11)
#define rb3(x) SPH_ROTL64(x, 27)
#define rb4(x) SPH_ROTL64(x, 32)
#define rb5(x) SPH_ROTL64(x, 37)
#define rb6(x) SPH_ROTL64(x, 43)
#define rb7(x) SPH_ROTL64(x, 53)
#define Kb(j) SPH_T64((sph_u64)(j) * SPH_C64(0x0555555555555555))
#if SPH_SMALL_FOOTPRINT_BMW
static const sph_u64 Kb_tab[] = {
Kb(16), Kb(17), Kb(18), Kb(19), Kb(20), Kb(21), Kb(22), Kb(23),
Kb(24), Kb(25), Kb(26), Kb(27), Kb(28), Kb(29), Kb(30), Kb(31)
};
#define rol_off(mf, j, off) \
SPH_ROTL64(mf(((j) + (off)) & 15), (((j) + (off)) & 15) + 1)
#define add_elt_b(mf, hf, j) \
(SPH_T64(rol_off(mf, j, 0) + rol_off(mf, j, 3) \
- rol_off(mf, j, 10) + Kb_tab[j]) ^ hf(((j) + 7) & 15))
#define expand1b(qf, mf, hf, i) \
SPH_T64(sb1(qf((i) - 16)) + sb2(qf((i) - 15)) \
+ sb3(qf((i) - 14)) + sb0(qf((i) - 13)) \
+ sb1(qf((i) - 12)) + sb2(qf((i) - 11)) \
+ sb3(qf((i) - 10)) + sb0(qf((i) - 9)) \
int
PFEMElement2D::update()
{
// get nodal coordinates
double x[3], y[3];
for(int a=0; a<3; a++) {
const Vector& coord = nodes[2*a]->getCrds();
const Vector& disp = nodes[2*a]->getTrialDisp();
x[a] = coord(0) + disp(0);
y[a] = coord(1) + disp(1);
}
// get c and d
double cc[3], dd[3];
cc[0] = y[1]-y[2];
dd[0] = x[2]-x[1];
cc[1] = y[2]-y[0];
dd[1] = x[0]-x[2];
cc[2] = y[0]-y[1];
dd[2] = x[1]-x[0];
// get Jacobi
double J = cc[0]*dd[1]-dd[0]*cc[1];
if(fabs(J)<1e-15) {
opserr<<"WARNING: element area is nearly zero";
opserr<<" -- PFEMElement2D::update\n";
for (int i=0; i<3; i++) {
opserr<<"node "<<ntags[2*i]<<"\n";
opserr<<"x = "<<x[i]<<" , y = "<<y[i]<<"\n";
}
return -1;
}
// get M
M = rho*J*thickness/6.0;
Mp = (kappa<=0? 0.0 : J*thickness/kappa/24.0);
double Mb = 9.*rho*J*thickness/40.0;
// get Km
Km.Zero();
double fact = mu*thickness/(6.*J);
for (int a=0; a<3; a++) {
for (int b=0; b<3; b++) {
Km(2*a,2*b) = fact*(4*cc[a]*cc[b]+3*dd[a]*dd[b]); // Kxx
Km(2*a,2*b+1) = fact*(3*dd[a]*cc[b]-2*cc[a]*dd[b]); // Kxy
Km(2*a+1,2*b) = fact*(3*cc[a]*dd[b]-2*dd[a]*cc[b]); // Kyx
Km(2*a+1,2*b+1) = fact*(3*cc[a]*cc[b]+4*dd[a]*dd[b]); // Kyy
}
}
// get Kb
Matrix Kb(2,2);
fact = 27.*mu*thickness/(40.*J);
double cc2 = 0., dd2 = 0., cd2 = 0.;
for(int a=0; a<3; a++) {
cc2 += cc[a]*cc[a];
dd2 += dd[a]*dd[a];
cd2 += cc[a]*dd[a];
}
Kb(0,0) = fact*(4*cc2+3*dd2); // Kxx
Kb(0,1) = fact*cd2; // Kxy
Kb(1,0) = fact*cd2; // Kyx
Kb(1,1) = fact*(3*cc2+4*dd2); // Kyy
// get Gx and Gy
Gx.Zero(); Gy.Zero();
fact = thickness/6.0;
for (int a=0; a<3; a++) {
Gx(a) = cc[a]*fact;
Gy(a) = dd[a]*fact;
}
// get Gb
Matrix Gb(2,3);
fact = -9.*thickness/40.0;
for (int a=0; a<3; a++) {
Gb(0,a) = cc[a]*fact;
Gb(1,a) = dd[a]*fact;
}
// get S
S.Zero();
if (ops_Dt > 0) {
Kb(0,0) += Mb/ops_Dt;
Kb(1,1) += Mb/ops_Dt;
}
if (Kb(0,0)!=0 && Kb(1,1)!=0) {
this->inverse(Kb);
}
S.addMatrixTripleProduct(0.0, Gb, Kb, 1);
// get F
F.Zero();
fact = rho*J*thickness/6.0;
F(0) = fact*b1;
F(1) = fact*b2;
// get Fb
Vector Fb(2);
fact = 9.*rho*J*thickness/40.;
Fb(0) = fact*b1;
Fb(1) = fact*b2;
// get Fp
Fp.Zero();
Fp.addMatrixTransposeVector(0.0, Gb, Kb*Fb, -1);
return 0;
}
