Progressive Collapse Mitigation in Multistory Tilt-up Structural Systems

Abstract

Low-rise office buildings constitute a large portion of the building inventory that is governed by criteria published by the US government. In recent efforts to save costs, building owners and others in this construction sector have explored the use tilt-up construction for these facilities, which eliminates the perimeter steel framing and integrates the concrete façade into the load bearing structure. According to the criteria, many of these buildings meet the height and occupancy thresholds for which progressive collapse resistant design is required. Two major US government agencies, DoD and GSA, provide methodologies for progressive collapse analysis of common structural systems. However these guidelines include limited guidance for the design of tilt-up construction. This paper outlines a methodology for progressive collapse resistant design of tilt-up structures and discusses the increases in reinforcement needed for a prototype building.