CPA Moment on the left is ~100*150kg/2. Moment on the right is ~ 250*150kg. A better approximation is 100*150kg moment plus a force of about 65N pushing just below the midpoint. Unbalanced forces will cause the CPA to rotate until the CG of the FC+CPA assembly is under the pivot point. If the bottom of the CPA is constrained the FC will will apply a moment at the top and push on the midpoint of the CPA panel.
This value represents one 2 This value represents one 2.3m wide CPA column picking up the load of one FC. If FC’s are erected on each side of the CPA as installation progresses from one endwall to the opposite, the deflection will be quite a bit less.
+ Pivoting on the CPA tube minimizes the off center load after installation Lifting the FC using a lightweight crane on support rails minimizes the moments during installation, but are we going to get too much bowing just from the convection forces?
Options proposed last Friday: 1 Add ribs back to the CPA design 2 Use a temporary stiffener for the CPA during installation. 3 Lift the FC into position with a light weight crane and support it by hanging it over the CPA tube. Other comments: With a thin CPA: The strength of the panel connection hardware should be checked for strength against the loading. The deflection of the CPA should be checked against the convection and pumping flows. Thin plates, even if ground, may not make for a flat 6m by 2.3m assembly? Also discussed last Friday was the fact that connections between CPA columns makes installation more challenging, more so for protoDUNE.
Back up slides