FE study of the reinforcement configurations of the vacuum vessel November 10th 2014 Method: individual interviews with group leaders based on the April schedule -> to gather bottom-up data, EN retreat on 1st July -> the aim was to bring the MTP in line with the last schedule & saving requests from the Council in June ENMB on 26th July -> validate with group leaders the top-down arbitration Norbert Kuder, EN/MME

Stiffeners Stiffener Mass (kg) Thickness (mm) 257 50 22.1 40 32.8 21.1 *188 for 36mm of thickness 50 22.1 40 32.8 21.1

Design concepts 1 2 3 4 5 6 7 8 9 11 10 original design 25x25mm + reinforcement on the top + 5mm thicker sides + additional support + stiffeners on the sides + thinner side stiffeners by 7mm + 5mm thicker the central plate + stiffener on the top + 2 columns Ø80 + 1 column Ø80 in the middle 1 2 3 4 5 6 7 8 9 11 10

Results 1 2 Spot Design 1 2 3 4 5 6 7 8 9 10 11 Total def. spot 1 (mm)    6 7 8 9 10 11 Total def. spot 1 (mm) 0.45 0.12 0.15 0.51 0.10 0.20 0.43 0.09 0.07 Total def. spot 2 (mm) 1.60 1.66 2.93 0.44 1.63 2.90 0.52 1.54 1.53 1.46 1.52 2 1

Total deformation #2 + reinforcement on the top

Total deformation #3 + reinforcement on the top + 5mm thicker sides

Total deformation #5 + reinforcement on the top + additional support

Total deformation #8 + reinforcement on the top + additional support + 5mm thicker the central plate

Total deformation #9 + reinforcement on the top + additional support + 5mm thicker the central plate + stiffener on the top

Total deformation #10 + reinforcement on the top + additional support + 5mm thicker the central plate + 2 columns Ø80

Total deformation #11 + reinforcement on the top + additional support + 5mm thicker the central plate + 1 column Ø80 in the middle

Conclusions The reinforcement of the openings decreases the deformation of the top plate almost 4-fold. Thicker sides bring more weight and dramatically increase the vertical deformation. The lateral stiffeners considerably increase the deformation of the top plate. Three supports are recommended to decrease the overall deformation. The increase of the central plate's thickness to 30mm with the top reinforcement decreases the deformation only by 0.02mm and 0.12mm on the sides. The additional stiffener on the top plate does not influence the deformation. The columns help to slightly decrease the deformation for the structure compare to the model with the reinforced openings. The models should be calculated taking into acount the weights of the magnetic and thermal screens.