The present work addresses the need for a proof of plate capacity under combined in-plane loads, a need recently highlighted by the loss of the post-panamax container ship MOL Comfort. Towards this end, an extensive series of numerical studies based on the finite element method have been performed covering all load combinations and plating configurations relevant for the shipbuilding industry. These studies have been used to investigate the mechanics of plating collapse (including the effects of plate slenderness and aspect ratio) under longitudinal, transverse and shear loads in isolation and in combination. Numerical studies have also been used to quantitatively evaluate existing proofs of plate capacity found in both literature and the shipbuilding industry. In this regard, quantitative acceptance criteria have been developed with which to judge whether a proof is (1) precise, (2) accurate and (3) robust. Similarly, qualitative criteria have been defined which require an acceptable proof to be (1) concise, (2) physically-based and (3) directly solvable. Because no existing proof was found to satisfy all quantitative and qualitative acceptance criteria, a hypothetical proof has been postulated using a generalised form of the von Mises equation (in order to satisfy qualitative acceptance criteria), where the exponents and interaction coefficient have been derived on the basis of observations made in the investigation of plating collapse mechanisms. To satisfy all quantitative acceptance criteria, the exponents and interaction coefficient of the hypothetical proof have subsequently been redefined on the basis of additional numerical studies (in case of biaxial compression only). Design application of the resulting proof has subsequently been explained and demonstrated. Because the new proof is based on numerical studies of simply-supported plates, uniform in-plane loads and idealised initial imperfections, the validity of its application has been demonstrated in case of other boundary conditions, additional load components and more realistic initial imperfections. Moreover, the marginal effect of out-of-plane loads (i.e.lateral pressure) on the in-plane capacity of plating has also been investigated. Finally, two examples of design application have been provided wherein the capacity of stiffened panels in the bottom shell and side shell of a double hull VLCC have been calculated both numerically and according to the new proof. Although the focus of the present work is on the capacity of plane plates, a new proof of curved plate capacity has been additionally presented. In terms of practical application in the shipbuilding industry, both proofs of plate capacity have been included in the newly harmonised IACS Common Structural Rules for Bulk Carriers and Oil Tankers, the new IACS Longitudinal Strength Standard for Container Ships as well as the new DNVGL Rules for Classification which are applicable to all ship types.weiterlesen