Structural fire safety is one of the primary considerations in the design of high-rise buildings, where steel is often the material of choice. One of the most common types of structural members in high rise buildings is the moment-resisting frame (MRF) members, which consist of beam-columns. The objective of this project is to develop simple tools and design guidelines for predicting the demands and capacity of steel beam-column structural systems under realistic fire, loading, failure, and geometric conditions. To achieve the above objectives, a collaborative research between Michigan State University (MSU) and Princeton University (PU) involving full-scale fire experiments and numerical studies is proposed under the following five tasks: (1) experimental investigation under real fire and loading scenarios; (2) finite element parametric study using coupled fire-heat transfer-structural interaction model; (3) predict the system behavior (i.e., demands) of beam-columns with thermal gradients; (4) evaluate the behavior of beam-columns (specifically perimeter columns) in frames; and (5) develop guidelines for evaluating fire resistance of beam-columns and transfer the information to codes and standards. The data from fire experiments in Task (1) will be used to validate and calibrate the finite element models in Task (2), which in turn will form the basis for developing simplified design tools and guidelines.
The intellectual merit of this research lies in developing design approaches for the highly complex problem involving fire-structure interaction of beam-columns. The proposed fire experiments studies are unique since it will lead to development of test data (for the first time) for beam columns under design fires, realistic loading, failure, and restraint scenarios. The proposed numerical studies involve tracing the highly complex behavior of a beam-column using coupled heat transfer/strain equilibrium analysis based on theoretical heat transfer and mechanics principles. Thus, the research proposed here lead to fundamental understanding on the fire behavior of beam-columns in the entire range of loading from pre-fire stage to collapse stages. The simplified equations and associated design guidelines will facilitate integration of fire resistance design into overall structural design and will lead to cost-effective and rational fire safety design of steel beam-columns in built infrastructure. Thus, the proposed research on beam-columns will form the basis for developing design guidelines to provide improved fire safety and contribute to the development of US codes and standards. The PIs have developed programs to disseminate the work to the practicing engineer, and they have developed a rich research experience for two PhD and three undergraduate students in structural fire safety area. One of the PIs is a woman and strong efforts will be made to recruit women and minority students.
