Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.

Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.

Decomposing a timbrel dome: Understanding the role of the structural elements in a complex masonry system

Andrew D Sorensen, University of Nebraska - Lincoln

Abstract

Starting at the beginning of the 20th century, over one thousand structures designed by the father and son team of Rafael Guastavino, Sr., and Rafael Guastavino, Jr., were constructed in North America. While these designs have been evaluated from an architectural history standpoint, research on their structural behavior is limited. Examples of Guastavino designs can be found in the timbrel domes of the Nebraska State Capitol (NSC) building. ^ This dissertation investigates how the elements that comprise a Guastavino timbrel dome interact to produce the general structural system behavior. To study these domes, a half-scale case study physical model (PM) of a dome located in the NSC is constructed. The PM is tested non-destructively using experimental modal analysis and the results are used to validate a finite element model (FEM). The validated FEM is decomposed into its elements of four arches and dome webbing. The interaction between the elements is determined, as well as the contribution of each layer of dome webbing tile to the system structural behavior. Parametric studies of the elements' geometry and material properties are carried out to determine their sensitivity to change. From these studies, scaling factors for natural frequency are developed. Using nonlinear FEMs, the load paths of the PM are determined for a load placed at the crown of the dome webbing. The PM is subjected to horizontal support movement and the results are corroborated with the nonlinear FEM results.^ This study determines that the elements of the system work together in series to develop the system behavior, and that the layers of dome webbing tile increase the static stiffness of the dome by approximately 50% per layer. Furthermore, it is determined that Guastavino domes are in fact pendentive domes, where the lower portion of the pendentives are part of the support system, and the dome can be simplified into a structure of two crossing arches that transfer the load to the pendentives and then the supporting piers.^

Subject Area

Engineering, Civil|Architecture

Recommended Citation

Sorensen, Andrew D, "Decomposing a timbrel dome: Understanding the role of the structural elements in a complex masonry system" (2009). ETD collection for University of Nebraska - Lincoln. AAI3378807.
http://digitalcommons.unl.edu/dissertations/AAI3378807

Share

COinS