In December, Hinman headed off to Seoul, South Korea to participate in the 7th International Conference on Design and Analysis of Protective Structures (DAPS) 2019. DAPS has been one of the most well-known international conferences for scientists and engineers who are interested in protective structures for the last 16 years. This conference first launched in 2003 because of a need for an international professional conference on design and analysis of protective structures against impact, impulsive, and shock loads.
For DAPS 2019, there were two featured speakers – Dr. Ted Krauthammer, (Chrome Professor of Civil Engineering at the University of Florida, and Director of its Center for Infrastructure, Protection, and Physical Security (CIPPS)) and Dr. Guoxing Lu (Professor of Impact Engineering at Swinburne University of Technology, Melbourne, Australia). They both supplied broader context for emerging challenges in protective design.
Building on this theme, Hinman’s Jaeyoon Kim presented his research on risk-based resilient design, highlighting novel approaches to quantify building structure risk for explosive hazard events. Spending a week with protective design experts allowed us to think about the future of our industry and consider what trends may lie ahead. Read on to catch two of our key takeaways from DAPS 2019.
DEVELOPMENT OF ADVANCED BLAST SIMULATORS
During the presentation given by Edward Gan (a PhD Graduate student), we had a chance to dive into how the current state of blast-resistant design largely relies on empirical observations of explosive testing. However, experimental data is very limited and many aspects of the blast response of structures are still unknown because of the dangerous, expensive, and uncontrolled variables in experimental blast test. A proper blast simulator must allow systematic and highly controlled blast experiments at much lower cost, greater safety, and higher fidelity than field trials. Advanced Blast Simulator was developed by University of Wollongong (Australia) as an ultramodern machine capable of generating a shock wave that replicates the wave-dynamics of an actual free-field explosion, including reproduction of the negative phase. They described the different subassemblies and components which make up the simulator. The driver has a divergent wedge-shape profile and can operate either in compressed gas or gaseous detonation modes, depending on the need. The Compressed Gas (CG) mode produces shock waves with a more pronounced and adjustable negative phase and with corresponding strong secondary shock. The Gaseous Detonation (GD) mode, by comparison, produces much stronger positive shock waves but is marked by a weaker negative phase. Additionally, GD mode has the operational advantage of not requiring the setup of a frangible diaphragm.
PROTECTION OF NUCLEAR POWER PLANTS
When it comes to the safety of nuclear plants, review of internal explosion scenarios is last step. Dr. Ji-Hun Choi (Post-Doc at Yonsei University, Korea) touched on how bi-directional pre-stressed concrete containment vessels (PCCVs) are commonly used to resist internal blast. However, the design code of PCCVs for blast load has not been developed. Chernobyl and Fukushima nuclear plant accidents revealed that PCCVs are vulnerable to extreme dynamic loads due to the brittle nature of PCCVs. From the literature, it has been reported that internal blast continuously reflects blast waves in a closed system. Unfortunately, internal blast pressure could not be directly captured because measuring devices such as pressure gauges are damaged in most tests. So, direct measurement of blast pressure has been proved as technically impossible. For this reason, there is no available data on the effects of internal blasts on structural members. In their study, a sophisticated and scaled-down test of a PCCV was designed to analyze its internal blast resistance.
As a world leader in integrated protective design, Hinman is committed to addressing these emerging challenges and providing adaptable solutions for complex projects in an ever-changing landscape. We have been trusted by federal, state, and regional agencies as well as private corporations for projects around the world. Our protective design strategies mitigate risk from potentially catastrophic events. Whether the project pertains to a single facility, a complex operation, or a portfolio of properties, we help clients understand the level of investment required to adequately protect against known and unknown risk.
For more information on the HIS-DAPS Conference or the paper on Risk-Based Resilient Design, contact firstname.lastname@example.org.