Container cranes are used to load and unload ships in ports and are critical to port operations. Past earthquakes have highlighted the vulnerability of container cranes to damage from even moderate earthquakes. During the 1995 Kobe, Japan earthquake,... [more]

Container cranes are used to load and unload ships in ports and are critical to port operations. Past earthquakes have highlighted the vulnerability of container cranes to damage from even moderate earthquakes. During the 1995 Kobe, Japan earthquake, a considerable fraction of the container cranes at the Port of Kobe either collapsed or were damaged beyond repair, leading to significant economic losses for the port and surrounding region. Cranes are unique structures and replacement of a failed structure can take more than a year. Their continued operation after an earthquake is critical to the continued operation of the port as well as post-disaster recovery for the region in which it is located. Despite their importance, the seismic performance of cranes has not been studied in the United States until now as part of a Network for Earthquake Engineering Simulation (NEES) Grand Challenge project sponsored by the National Science Foundation (Award No. CMS-0530478). Several types of earthquake-induced damage are common in container cranes. The first type of damage occurs when earthquake ground shaking causes the crane to derail. A derailed crane cannot be used, but it only takes several days to replace the crane on the rails. The second type is localized structural damage to the crane. This is more severe because the damaged portions must be repaired or replaced, which may take several months. The most severe type of damage is collapse, which requires the entire crane to be replaced. To get a better understanding of how container cranes respond during an earthquake, a 1/10th scale model of a container crane has been designed and will be tested on the shake table at the University at Buffalo, one of 14 facilities for large-scale testing that are part of the NEES network. The shake table has the ability to simulate the motions of the ground during an earthquake. The objective of the test is to measure the response of the crane from small levels of shaking to those large enough to cause the test crane to collapse. The data collected during the test will provide information on the likelihood of each type of damage as a function of the level of shaking and allow computer models of cranes to be developed and verified. When damage occurs in the test crane, repairs similar to those used in the field will be made to the structure. The repaired crane will be tested again to determine how well the repairs perform during subsequent earthquakes. The upcoming test will be the largest ever performed in the United States and the first shake table test in the world to test to collapse. The information from the test will be used to assess the expected performance of existing container cranes and, if necessary, design retrofit measures to reduce the possibility of damage during earthquakes. The test results will also be used to develop improved design standards for future cranes. [less]

Development of a Performance-Based Seismic Design Philosophy for Mid-Rise Woodframe Construction. Evaluate seismic response of engineered wood construction.The test structure is a single unit from a two-story townhousedesigned to the 1998 UBC. Thestr... [more]

Development of a Performance-Based Seismic Design Philosophy for Mid-Rise Woodframe Construction. Evaluate seismic response of engineered wood construction.The test structure is a single unit from a two-story townhousedesigned to the 1998 UBC. Thestructure is approximately 53 x 23 feet in plan andtwo stories tall. The structure will be subjected to theNorthridge ground motion at varying levels ofintensity and for various levels of structural finish, i.e.OSB only, stucco, etc. The tri-axial un-scaledRinaldi record will also be used. The structure willbe repaired between test phases. [less]

The Zipper Frames project is a collaborative NEES project between Georgia Tech, University at Buffalo, UC Berkeley and University of Colorado at Boulder. The model that is going to be tested is a particular variation from the traditional zipper frame... [more]

The Zipper Frames project is a collaborative NEES project between Georgia Tech, University at Buffalo, UC Berkeley and University of Colorado at Boulder. The model that is going to be tested is a particular variation from the traditional zipper frame. It was first developed at GeorgiaTech and it is called the suspended zipper frame, where the top braces are designed to remain elastic during a ground motion, preventing the frame to become unstable.The purpose of this experiment is to perform a shaking table test with the suspended zipper frame and monitor the sequence of yielding and bucking of the braces. The objective of the experiment is to understand the actual behavior of the zipper configuration during a ground motion. Being aware that phenomena like buckling of braces are not directly scalable and the results could possibly not be extrapolated to a full scale structure, the test will be very useful to validate analytical work and assumptions made in simplified computational models. [less]