Body Forces - The Boundary Element Method with Programming - page 353

C4= 1.0 - 2.0*LOG(1.0/r)
II(1:3)= (/1,2,1)
JJ(1:3)= (/1,2,2)
Stress_components: &
DO N=1,3
I= II(N) ; J= JJ(N)
IF (I == J) THEN
C= ny*(2.0*costh*cospsi-cosphi)+(1.0-2.0*LOG(1/r))cosphi
ELSE
C= 0.0
END IF
SK(N)= C2*(C - cospsi*(Vnor(I)*dxr(J)+ Vnor(J)*dxr(I)) &
- 0.5 *(cospsi*(Vnor(I)*dxr(J)+ Vnor(J)*dxr(I)) &
+ C3*(b(I)*Vnor(J) + b(J)*Vnor(I)))
END DO
Stress_components
SK= C1*SK
ELSE ! Three-dimensional solution
II= (/1,2,3,1,2,3)
JJ= (/1,2,3,2,3,1)
C1= 1.0/(8*Pi*r)
Stress_components1: &
DO N=1,6
I= II(N) ; J= JJ(N)
C=0.
IF (I == J) THEN
C= c2*ny*(costh*cospsi-cosphi)
ELSE
C= 0.0
END IF
SK(N)= 2.0*costh*(b(I)dxr(J)+ b(J)dxr(I))+ C &
-0.5 *(cospsi*(Vnor(I)*dxr(J)+ Vnor(J)*dxr(I))&
+ C3*(b(I)*Vnor(J) + b(J)*Vnor(I)))
END DO &
Stress_components1
SK= C1*SK
END IF
RETURN
END

13.3 INTERNAL CONCENTRATED FORCES

It is sometimes necessary to apply concentrated forces inside the domain. An example of
this is the simulation of a pre-stressed rock bolt in tunnelling, where a concentrated force
is generated inside the domain. Acc o rding to figure 13.2, additional work is done by a
concentrated force F acting at point Q .