Blast & Impact Loading & Response of Structures
A pair of decommissioned thirteen-story reinforced concrete buildings were demolished via controlled implosion at the University of Nebraska-Lincoln in December 2017. The implosion consisted of controlled charges at select columns on alternating floors throughout the buildings, which initiated the collapse of the two buildings. This controlled implosion provided the rare opportunity to monitor and characterize the collapse progression of the buildings as well as the response of nearby and adjacent structures to both the remote blast loading and the subsequent building collapse. To this end, sacrificial accelerometers were placed throughout the two buildings prior to the collapse to record the buildings’ motions and load redistribution. In addition to these sensors, additional accelerometers were placed in the free field and within three nearby structures, including two immediately adjacent structures as well as one high-rise at an approximate distance of 0.25 mile. These sensors monitored the adjacent structures before, during, and after the collapse to understand the impact of the collapse. While no noticeable damage nor shift in the natural frequencies were observed in the adjacent structures, each exhibited observable response to both the blast sequence as well as the collapse sequence of the buildings, with accelerations on the order of 0.05 g at the ground outside the closest building and 0.005 g at the furthest structure. This experimental dataset is expanded upon through detailed finite element analyses of the structure-soil-structure interaction in LS-DYNA. In this paper, this unique dataset will be introduced alongside key observations of the performance of the pair of buildings as well as that of the adjacent structures.