Mitigating the Potential for Progressive Disproportionate Structural Collapse: 20 - Tapa blanda

The twelve papers in this collection accurately represent the current state of practice and research regarding the subject of progressive collapse and the design implications of emerging codes and standards. Although there is debate among design professionals as to the need for more specificity given the limited number of historic events that resulted in structural collapse, U.S. government construction practice is demanding greater attention to damage state design requirements and developers of commercial property are demanding greater robustness of their major construction projects. The American Society of Civil Engineers (ASCE) and the National Institute of Standards and Technology (NIST) are leading the profession towards standards that may some day become design requirements. The following papers address different technical challenges and observations associated with increased structural robustness. Some of these papers help define the issues, while others relate the practices mandated by different criteria. Other papers present observations based on bomb damage data and controlled demolition practice. Risk mitigation for a range of hazardous conditions is compared and the means to describe the consequences of low probability events are identified. Many of these papers address the different analytical approaches that may effectively predict the performance of structures as a result of damage state conditions.