at the opposite side of the wall each of the i beams extends the full height of the dividing wall 40 each pair of beams is connected by a plurality of fasteners 52 between the i beams when the fasteners 52 are tightened the beams are pressed against the opposite sides of the wall 40 and that fixes the boards 41 42 et al of the dividing wall in alignment over the height of the wall and keeps the adjacent horizontal boards abutting to seal the dividing wall first truss rods 54 56 are spaced from but near to respective opposite sides of the dividing wall 40 with the dividing wall on a diameter of the tank each of the first truss rods 54 56 extends on a chord across the width of the tank the first truss rods pass through holes 57 formed in the i beams 48 50 the first truss rods pass through the side walls of the tank the above described hoop segments 19 have holes that receive the ends 59 of the first truss rods 54 56 so that the first truss rods are tightened into the hoop segments 19 on the outside of the shell of the tank this pulls radially inward the staves of the tank wall including the staves that receive the first truss rods 54 and 56 this tightens the hoop segments 19 against the staves there is a respective channel cover 58 at the top of the tank just outward of the truss rods 54 and 56 in fig4 and 5 there is a fixture 60 and 62 at each side of the dividing wall 40 just below the height.