Joint analysis during vault lowering of the Officer Sean Collier Memorial

Abstract

The unique geometry and indeterminacy of the Collier Memorial make it a highly complex structure to analyze. During the critical vault-lowering phase of the construction of the memorial, joints were monitored to understand where and how the memorial deformed. Joint displacements are aggregated into figures to allow for a visual representation of the joint displacements working in conjunction with one another. With the visualization of the displacement data, it was determined that a hinging mechanism formed in one of the legs. The majority of the self-weight, about 96%, was transferred to the supporting walls in compression during the lowering of the vault. Joint displacements were also used to assess the actual thrust states of two legs to be compared to analytical and numerical models generated during the design phase. The mechanics of the multipolymer shim used as the intermediary between the granite blocks were studied. The joint displacements in combination with the shim mechanics produced thrust values within the minimum and maximum thrust range established by a thrust line analysis.