Horizontal Support Displacement of a Thin-Tile Masonry Dome: Experiments and Analysis

Abstract

A half-scale physical model of a thin-tile masonry dome designed by Rafael Guastavino, Jr. that is located in the Nebraska State Capitol Building is constructed and tested both nondestructively and destructively to determine the load paths of the structure as well as the reactions at the support. A corner support of the model dome is incrementally displaced horizontally and the resulting crack locations are identified. Additionally, a linear finite element model of the dome, validated with experimental modal analysis, is modified to perform nonlinear analysis where loads are placed on the dome and the resulting stresses and reactions determined. The results from the nonlinear finite element model are then compared to the destructive testing carried out on the constructed physical model. From the results of both the nondestructive and destructive testing, it is determined that the thin-tile masonry dome in question acts as a pendentive dome, which exerts horizontal thrust as well as vertically transmitting a portion of the load to the supporting columns. Additionally, the results show that the quarter points of the arches and dome webbing pendentives experience the highest stress levels under both vertical loading at the crown and horizontal support displacement, and as such are the most susceptible to initiate the system failure.