Roberts, D.M.Vozzo, R.F.2026-03-112026-03-112026Journal of Homotopy and Related Structures, 2026; 1-662193-84071512-2891https://hdl.handle.net/2440/148929OnlinePublMotivated by the problem of constructing explicit geometric string structures, we give a rigid model for bundle 2-gerbes, and define connective structures thereon. This model is designed to make explicit calculations easier in applications to physics. To compare to the existing definition, we give a functorial construction of a bundle 2-gerbe as in the literature from our rigid model, including with connections. As an example we prove that the Chern–Simons bundle 2-gerbe from the literature, with its connective structure, can be rigidified—it arises, up to isomorphism in the strongest possible sense, from a rigid bundle 2-gerbe with connective structure via this construction. Further, our rigid version of 2-gerbe trivialisation (with connections) gives rise to trivialisations (with connections) of bundle 2-gerbes in the usual sense, and as such can be used to describe geometric string structures. The preprint of this article is available as arXiv:2209.05521.en© The Author(s), under exclusive licence to Tbilisi Centre for Mathematical Sciences 20262-gerbes; higher geometry; rigid models; Chern–Simons theoryJournal article10.1007/s40062-025-00381-w997881Roberts, D.M. [0000-0002-3478-0522]