Objectives  In order to effectively reduce the bending stress of the upper deck in a rectangular pressure cabin,

  Methods  a scheme of prestressed pillars in a pressure cabin is put forward. First, in the case that the layout and size of the pillars are given, a mathematical model of pillar optimization is proposed in which the pre-stresses of pillars are treated as the design variables and the upper deck bending stress as the objective function, and the stress constraints of the pillars are considered. The pillar position is then further treated as a design variable, and the optimization design of pillar layout and prestressed pillar configuration is carried out.

  Results  The optimization results show that the bending stress of the upper deck frame is reduced by 21.6% while pillar weight does not increase. Furthermore, the upper deck bending stress further decreases by 16.0% while pillar weight still does not increase.

  Conclusions  The research achievements of this paper provide useful references for similar structural design.