March 10, 2011
Multi-Hazard Risk Mitigation: One Size Fits All
by Brian Katz
The next frontier in engineering innovation may largely center around endeavors to take the understanding of project specific needs to a higher level. This approach has the potential to more optimally match engineering solutions to the needs of structure and enhance the efficiency of the design process.
February 24, 2011
The Effect of Fire Following an Extreme Event
by Spencer Quiel
The ability of a structure to resist a disproportionately large collapse due to localized damage (i.e. progressive collapse) has become a topic of increasing concern within the building community in the wake of structural collapses worldwide over the last half century… The goal of this study is to raise awareness of potential fire hazards that may follow extreme events and provide recommendations regarding evacuation times for occupants of damaged buildings under fire.
February 24, 2011
Terrorist Risk Assessment and Mitigation of Bridges
by Andy Coughlin
In 2003, the Blue Ribbon Panel on Bridge and Tunnel Security issued its recommendations for risk assessment and mitigation of bridges and tunnels. The report gives general guidelines to help decision makers improve the security of bridges and tunnels. However, the actual implementation can be highly dependent on the methods used to carry out the assessment.
February 24, 2011
Performance Limits for Progressive Collapse
by Steve Wopschall
Progressive collapse is an extreme loading event that requires identifying and engaging all necessary and available load paths within a structure. Most recently, Hinman engineers have conducted a nonlinear dynamic finite element analysis of an existing 33-story high rise structure with the intent of pushing the limits of structural performance. Hemmed in by the constraints of the current governing criteria, project engineers found structural performance to be limited by the required use of seismic documentation. When costs and upgrades are a concern, and collapse is the question, it appears to be necessary to redefine the problem of progressive collapse.
February 24, 2011
Innovation in Motion: Cable Catchment Systems
by Seda Dogruel
Preservation of exterior window systems is an important aesthetic consideration when renovating historic buildings. The need to improve the protective quality of this component of the building envelope while maintaining the existing façade expression presents both challenges and opportunities to apply innovative threat mitigation technologies. In exploring various window retrofit options, blast engineers must balance the demands of likely threat scenarios against a variety of other design objectives pertaining to cost, energy performance, window operability and constructability. The final result is, ultimately, a system that is a threat mitigation solution uniquely tuned to meet project specific goals and preserve the identity of the historic structure.
February 24, 2011
Concrete Anchorage for Extreme Loading
by Dan Gavahi
ACI 318 Appendix D provides a design procedure… not well suited for atypical loads such as those resulting from an explosive event. In fact, Appendix D explicitly states that high cyclic fatigue or impact loads, like blast, are outside of its scope… Our hope is to encourage a collaborative effort with manufacturers and academia to develop a suitable design protocol that may be incorporated into future editions of ACI 318
February 19, 2011
Design Innovations Needed for Disaster Protection
by Eve Hinman
A quarter of a century ago when I started in the field of protective design of civilian buildings, a series of simplifying assumptions were made to enable engineers to effectively respond to this new need. When infused with engineering judgment, the results of these analyses could be used to effectively reduce the vulnerability of high risk buildings without unreasonable cost or aesthetic impact.
Today, our understanding of the true threat that our infrastructure faces is considerably more sophisticated and not aligned well with the basic assumptions originally made. These threats include not only terrorist attack, but natural hazards and accidents as well.
February 19, 2011
GreenBlast : Protect the Built & Natural Environments
by Caroline Field
Two of the biggest challenges facing the world today are Global Warming and Terrorism. Ironically, the more we deplete our natural resources, the more we will need to protect what we have left. Is this inevitable? What small part can we, as blast consultants play in derailing this path?
February 07, 2011
Minimizing terrorist risk with the “power of people”
by Andy Coughlin
On a recent site visit, two Hinman engineers had a curious experience while taking measurements of windows in an occupied federal building. Though the engineers were authorized by building maintenance and security to take photographs and measurements, most of the hundreds of employees in the building were not informed of their visitors that day. Security later informed the Hinman engineers they had received call after call from concerned employees reporting the “suspicious” activity which was taking place outside the building.
January 19, 2011
ATFP Design of Military vs. Civilian Federal Facilities
by Eve Hinman
I had the honor of providing expert testimony to the U.S. House of Representatives Committee on Transportation and Infrastructure on the risk implications of applying the DoD Minimum Antiterrorism Standards for GSA lease procurements. The House is concerned about the cost of providing the large setback distances required by DoD standards for new facilities housing “back office” DoD operations located within an office park or downtown location with an uncontrolled perimeter.
