InfrastructureTesting the seismic strength of light frame steel construction

Published 18 June 2013

A partnership of leading earthquake engineering researchers from top U.S. and Canadian universities and design professionals from the steel industry have begun the final phase of a three-year project to increase the seismic safety of buildings that use lightweight cold-formed steel for their primary beams and columns. Research to conclude with shake-table testing.

A partnership of leading earthquake engineering researchers from top U.S. and Canadian universities and design professionals from the steel industry have begun the final phase of a three-year project to increase the seismic safety of buildings that use lightweight cold-formed steel for their primary beams and columns.

Funded by a grant from the George E. Brown Jr. Network for Earthquake Engineering Simulation Network (NEES), the researchers have already developed a series of computational models to determine how a complete building structure will perform during an earthquake.

Headquartered at Purdue’s Discovery Park, NEES is a collaborative, 14-site research initiative that aims to improve structural seismic design and reduce the damaging effects of earthquakes and tsunamis.

NEES is funded by a $105 million National Science Foundation grant. NEEScomm is the operations unit at Purdue.

A Purdue University release reports that the initial stage in the testing involved the construction of a two-story structure and then testing on a “shake table” at the University of Buffalo. The building will undergo the rigors of a controlled earthquake to determine how it performs. There will be two phases to the shake table testing: Phase One is taking place 12-14 June and will test only the structural components, which include the cold-formed steel skeleton and the OSB (oriented strand board) sheathing for the floor diaphragm and roof; Phase Two will add non-structural components like stairs, gypsum sheathing and interior partitions.

The objective is to advance cold-formed steel light-frame design in buildings to the next level and equip engineers to implement these performance-based seismic designs in their projects.

The data from the research is published on NEEShub, the cyberinfrastructure component of the NEES network. The NEEShub platform is powered by Purdue’s HUBzero software.

The research team is led by Benjamin Schafer of the Department of Civil Engineering at Johns Hopkins University and a longtime member of two standards-developing committees of the American Iron and Steel Institute (AISI) — the Committee on Specifications and the Committee on Framing Standards. Schafer’s team includes additional researchers from Johns Hopkins and Bucknell University, with input from colleagues at the University of North Texas, Virginia Tech, and McGill University in Montreal, Canada.

Several steel industry partners are participating in the project, providing technical expertise, donated materials and additional funding. The steel industry partners include the American Iron and Steel Institute, Bentley Systems Inc., ClarkDietrich Building Systems, Devco Engineering Inc., DSi Engineering, Mader Construction Co. Inc., Simpson Strong-Tie Co. Inc., the Steel Framing Industry Association, and the Steel Stud Manufacturers Association.

We appreciate the valuable technical and economic input that our industry partners have provided,” said Schafer, the project’s principal investigator.

This project has already resulted in several innovations that will immediately impact seismic cold-formed steel design standards, making buildings safer,” Schafer said. “Now comes the fun part — getting to see how all the research plays out on the shake table. One of the important deliverables from this project will be the transfer of our research results into an open-source software framework.

The data will then be made available to engineers, allowing them to see how their structural system designs will respond to an earthquake before they are constructed. This software will create cost efficiencies and potentially save lives.”

In fact, project data is already on NEEShub. Preliminary testing conducted on building components (shear walls in particular) have been posted for engineers to examine. Initial uploading of the test data happens immediately after the tests. Fully curated data will happen over the course of this summer.

Schafer said Johns Hopkins graduate student Kara Peterman is on site at the University of Buffalo Structural Engineering and Earthquake Simulation Laboratory (SEESL) and is providing updates on the structure’s construction and blog entries at the CFS NEES blog.