PROGRAM BSEC
C.... PROGRAM TO COMPUTE PROPERTIES AND 
C     STRESSES IN BEAM
      REAL B(3),D(3),X(4),Y(4),S(4),XMX
      REAL XMY,YD,A,AY,XI,YI,SD,P,BD
      INTEGER I
C.... ASK USER FOR BASIC DIMENSIONS
 50   WRITE(*,2000)
      READ(*,1000) B
      IF(B(1).EQ.0.0) STOP
      WRITE(*,2001)
      READ(*,1000) D
C.... ASK USER FOR MEMBER LOADS
      WRITE(*,2002)
      READ(*,1000) P
      WRITE(*,2003)
      READ(*,1000) XMX,XMY
C.... PRINT INPUT DATA
      WRITE(*,2004) B,D,P,XMX,XMY
C.... EVALUATION OF SECTION PROPERTIES
      YD = 0.0
      A  = 0.0
      AY = 0.0
      XI = 0.0
      YI = 0.0
      SD = 0.0
C
      DO 100 I = 1,3
         BD = B(I)*D(I)
         SD = SD + D(I)
         A  = A + BD
         YD = SD + 0.5*D(I)
         AY = AY + BD*YD
         XI = XI + BD*D(I)*D(I)/12.0 + A*YD*YD
 100     YI = YI + BD*B(I)*B(I)/12.0
C
      YD = AY/A
      XI = XI -A*YD*YD
C
      WRITE(*,2005) YD,A,XI,YI
C.... EVALUATE STRESSES
      X(1) = 0.5*B(1)
      X(2) = -X(1)
      X(3) = X(1)
      IF(B(2).NE.0.0) X(3) = 0.5*B(2)
      IF(B(3).NE.0.0) X(3) = 0.5*B(3)
      X(4) = -X(3)
      Y(1) = YD
      Y(2) = YD
      Y(3) = YD - SD
      Y(4) = Y(3)
C
      DO 200 I = 1,4
 200     S(I) = P/A + XMX*Y(I)/XI + XMY*X(I)/YI
C     
      WRITE(*,2006) S(2),S(1),S(4),S(3)
C
      GOTO 50
C.... FORMATS
 1000 FORMAT(3F10.0)
 2000 FORMAT(/'B E A M   S E C T I O N   P R O G R A M'//
     &     'ENTER BEAM WIDTHS (B1,B2,B3 - 0 TO TERMINATE) = ')
 2001 FORMAT('ENTER BEAM DEPTHS (D1,D2,D3) = ')
 2002 FORMAT('ENTER AXIAL FORCES (NEG. FOR COMP.) = ')
 2003 FORMAT('ENTER MOMENTS MX AND MY')
 2004 FORMAT(/'S U M M A R Y   O F   I N P U T   D A T A'/
     &     'BEAM WIDTHS        = ',3F10.3/
     &     'BEAM DEPTHS        = ',3F10.3/
     &     'AXIAL FORCES       = ',1F10.2/
     &     'SECTION MOMENTS    = ',2F10.1)
 2005 FORMAT(/
     &     'DISTANCE TO N.A.   = ',1F10.3/
     &     'AXIAL AREA         = ',1F10.3/
     &     'IXX                = ',1F10.1/
     &     'IYY                = ',1F10.1)
 2006 FORMAT(/'C A L C U L A T E D   S T R E S S E S'
     &     //2F15.4//2F15.4/)
      END