ASCE has honored Erica C. Fischer, Ph.D., P.E., M.ASCE, with the 2019 Collingwood Prize for the paper “Experimental Evaluation of Single-Bolted Lap Joints at Elevated Temperatures,” Journal of Structural Engineering, January 2018.
The mentioned paper summarizes a series of tests performed at Purdue University that measured the axial force–displacement–temperature relationship of lap splice joints. The field of structural fire engineering consists of designing and analyzing buildings for the load effects due to fire, rather than using the prescriptive approach per the International Building Code. To perform such analyses, complex nonlinear finite element models are necessary to simulate the nonlinear material behavior of steel and the inherent fire resistance of the building through lateral restraint and load redistribution. While the gravity frame connections are designed for vertical shear force only at ambient temperature, structural fire engineering entails designing these connections for the loads imposed throughout both the heating and cooling phases of the fire. These loads include large axial tensile demands during the cooling phase. To design for these demands, engineers must quantify the temperature-dependent load-displacement capacity of the connections.
The results presented by Fischer in her paper experimentally benchmark numerical codes previously developed for the temperature-dependent load-displacement capacities for connections failing in bolt shear fracture and bolt bearing. While the relationships have previously been benchmarked for bolt shear fracture, these experiments occurred in the UK, where ASTM A325 bolts are not used. The plate bearing numerical models had yet to be benchmarked against experimental tests. The results from the tests that Fischer rationally summarized showed that the lap splice joints will fail in tearout failure, which results in a sudden loss of carrying capacity, rather than the gradual decline in load-carrying capacity that bolt bearing failure implies. These results are paramount in the development and furthering of the structural fire engineering field, especially for the work being produced through the ASCE fire protection committee.
Fischer has been active in the ASCE Fire Protection Committee. Her esearch has a direct application to the products the committee is developing. She has been involved in the writing and development of the Structural Fire Engineering Manual of Practice, recently published. This manual provides background and knowledge to structural engineers to implement structural fire engineering on projects throughout the United States. She is currently serving as an academic advisor on the joint Charles Pankow Foundation and Structural Engineers Institute project to develop exemplar procedural guidance on how to use the Manual of Practice.
The paper demonstrates that the author has significantly contributed to the engineering body of knowledge through the experiments she performed. These experiments begin to experimentally benchmark critical modeling techniques and methodologies that structural engineers will require as they employ structural fire engineering on structural engineering projects.
The Collingwood Prize is awarded to the author or authors, under 35 years of age, of a paper describing an engineering project with which the author is directly connected, or recording investigations contributing to engineering knowledge to which the author has made some essential contribution and which contains a rational digest of results.
