center for infrastructure protection and physical...

J ANU ARY—MARCH 2013

Center for Infrastructure Protection and Physical Security (CIPPS)

Powell Structures & Materials Lab 1-3

Publications & Aca-demic Courses and

Training 4

Academic Courses & Critical Infrastructure Protection Certificate

5

Technical Visits / Activities &

Sponsored Research 6

Examples of Research &

Development 7-9

Announcements & Our Mission 10

Seminars & Conferences 11

Our Sponsors, New Activity, Jobs 12

INSIDE PG

INSIDE THIS ISSUE:

CIPPS Headquarters

Inside Powell Structures and Materials Lab

The Powell Family Structures and Materials Laboratory is located on the East Campus of the Uni-versity of Florida and is part of the Department of Civil and Coastal Engineering. The facility con-sists of a 6000-square foot lab space with a 30-foot-high ceiling and a 4-foot-thick concrete strong floor, a 2000-square foot machine shop with a 12-foot ceiling, a 5000-square foot general lab space with a 16-foot high ceiling, a 120-linear foot wind tunnel, a 220-square foot instrumentation room, and several offices and storage rooms. Research in this facility is primarily directed at earthquakes, hurricanes, tornados, and blast/impact in the context of structural damage mitigation and human intervention. http://www.essie.ufl.edu/facilities/powell_family_structures_and_materials_laboratory/

Modern Protective Structures Short Course Now accepting registra-tions, and seats are lim-ited. See Pg. 10 for more information and the link for registration.

CENTER FOR INFRASTRUCTURE PROTECTION AND PHYSICAL SECURITY

Inside Powell Structures and Materials Lab (Cont.)

Powell Structures and Materials Lab has several components that are essential to the research work of the College of Engineering. CIPPS testing equipment and materials are located in the lab, as seen in these photos. There are two different types of drop hammers that are used to test the stability of various types of concrete under pressure and impact. Other equipment, such as the Data Acquisition Computer (DAC), various meters, and video and camera equipment, provide the information we use to support testing for our projects.

Powell Structures & Materials Lab

4,000 lb. Drop Hammer

Variable Mass Drop Hammer

Machine Shop

and Fabrication Area

Powell Structures & Materials Lab


Six-Degree-of-Freedom Shake Table Recently installed in the lab is a 4-ft × 4-ft six-degree-of-freedom shake table with a 1-ton payload and ±6 in. of stroke in each of the x-, y-, and z-directions. The shake table is powered by a 125-HP Hydraulic Power Unit capable of pressures up to 3000 psi. The complex motion generation capabilities of the shake table will enable testing and monitoring of the structural response of scale models and components in a controlled environment.

Wind Tunnel Under development is a 120-ft × 20-ft’ Boundary Layer Wind Tunnel. It is powered by 2.09 MW (2800 HP) comprising four 0.52 MW (700 hp) marine Detroit Diesel engines that spin eight hydraulically actuated vaneaxial fans. To recreate the boundary layer profile, an active computer control system modulates wind speed by varying fan RPM that pass through several screens and honeycombs before it reaches the test specimen. The control system uses a PID-control system operated in the LabVIEW environment.


MABS 2012, Military Aspects of Blast & Shock

Normal Strength & Ultra-High-Performance Concrete Beams under Impact, T. Krauthammer, D. Koch, M. Stone, S. Astarlioglu, L. Bui Abstract Concrete is one of the most widely utilized building materials because of its cost and wide range of applicability. Ultra-high-performance concrete (UHPC) is a reactive powder concrete that is combined with admixtures and steel fibers to produce a denser, stronger, and more durable material than normal-strength concrete (NSC). This study was dedicated to dynamically test full-scale UHPC beams and also to focus on the effects of strain rate on UHPC. The data obtained from these test were used to validate finite element models cre-ated with the computer code ABAQUS, as well as the Dynamic Structural Analysis Suite (DSAS) to predict the results. The predicted data were used to design a series of NSC and UHPC beams that were tested statically and under impact to study their physical behav-ior, and to define the effect of the materials on the observed performance. Plastic Hinge Formation in Reinforced Concrete & Ultra-High-Performance Concrete Columns under Dynamic Loads T. Krauthammer, S. Astarlioglu, and L. Bui Abstract Columns are critical structural elements, and their behavior under dynamic loads was the focus of this study. Ultra-high-performance concrete (UHPC) is an emerging engineering technology characterized by increased strength and durability compared with normal- and high-performance concretes. The study examined the process by which plastic hinges form along a column, and the effect of such de-velopment on the column’s response under various boundary and load conditions. The considered normal-strength concrete (NSC) and UHPC columns were addressed with both the fast-running computer code DSAS, and the finite element program ABAQUS. The behav-iors obtained from such simulations were compared, and conclusions were drawn about the various aspects of the simulations, the used parameters, and the observed structural behaviors. Numerical Assessment of Direct Shear Behavior in Concrete D. Lavenhagen, T. Krauthammer, S. Astarlioglu, L. Bui Abstract The direct shear behavior of concrete in the dynamic domain is not well understood. Furthermore, simulating such behavior numerically with a finite element program has not been mentioned in the literature. This paper is aimed at describing the numerical simulation of direct shear specimens using the explicit finite element code ABAQUS, and at validating such an approach. It is unknown whether the current material models for concrete in ABAQUS can accurately represent the shear stress-shear slip relationship. This will be accom-plished by comparing the numerical results with test data obtained by other researchers. Furthermore, the Hawkins shear transfer mod-el will be used to investigate its appropriateness in predicating the shear stress-shear slip relationship of the same cases. Behavior of Reinforced Concrete Columns under Combined Effects of Axial and Blast-Induced Transverse Loads S. Astarlioglu, T. Krauthammer, D. Morency, T. P. Tran Abstract The results of numerical studies on the dynamic response of reinforced concrete (RC) columns subjected to axial and blast-induced transverse loads using an advanced single-degree-of-freedom (SDOF) model are presented in this paper. The main variables consid-ered in this study were the level of axial force and longitudinal reinforcement ratio. This work addressed the effect of various levels of axial compressive load on the resistance function, time-history response, and load–impulse diagram when the columns were subjected to transverse loads due to blast. The blast loads were idealized as triangular pulses and the effects of flexural, diagonal shear, and ten-sion membrane behaviors were included in the RC column response. The results from the SDOF analyses were validated using the commercial finite element (FE) program ABAQUS. The results of the parametric study indicated that the level of axial compressive load has a significant influence on the behavior of RC columns when subjected to transverse blast-induced loads. (Engineering Structures, In Press, Available online 13 Feb 2013)

Publications

Technical Reports to Sponsor • Astarlioglu, S., Krauthammer, T., and Felice, C. 2013. State-of-the-Art Report on Fiber-Reinforced, Ultra-High-Performance Con-

crete, 2nd ed., CIPPS Technical Report No. CIPPS-TR-001-2013, Center for Infrastructure Protection and Physical Security, Uni-versity of Florida.

• Astarlioglu, S., Bui, L., and Krauthammer, T. 2013. The Behavior of Reinforced Concrete and Ultra-High-Performance Concrete Columns with Plastic Hinges under Impact and Blast Loads, CIPPS Technical Report No. CIPPS-TR-002-2013, Center for Infra-structure Protection and Physical Security, University of Florida.

• Koch, D., Stone, M., Krauthammer, T., Astarlioglu, S., and Bui, L. 2013. Investigation of Static and Impact Response of Normal-Strength and Ultra-High-Performance Beams, Part I: Static Behavior and Preparation for Impact Tests, CIPPS Technical Report No. CIPPS-TR-003-2013, Center for Infrastructure Protection and Physical Security, University of Florida.

• Lavenhagen, D. and Krauthammer, T. 2013. A Numerical Assessment of Direct Shear Behavior in Concrete, CIPPS Technical Re-port No. CIPPS-TR-004-2013, Center for Infrastructure Protection and Physical Security, University of Florida.

• Friedrich, N. Astarlioglu, S., and Krauthammer, T. 2013. Impact Loading on Ultra-High-Performance Fiber-Reinforced Concrete, CIPPS Technical Report No. CIPPS-TR-005-2013, Center for Infrastructure Protection and Physical Security, University of Florida.

Technical Reports


Technical Visits

Technical Visits • 17–21 December 2012: Prof. Krauthammer visited the Republic of Korea for technical meetings with the Agency for Defense

Development, Korea Institute for Construction Technology, and the Research Institute of Industrial Science and Technology.

• 4–8 February 2013: Prof. Krauthammer visited Japan for meetings with the National Defense Academy, Japan Ministry of De-fense and Japan Self Defense Forces, and Taisei Corporation Technology Center. Also, he presented a keynote lecture during the annual meeting of the Japan Society of Defense Facility Engineers.

The technical staff at CIPPS have been involved in a broad range of projects in the following areas:

• Blast containment and explosive safety assessment

• Blast- and impact-resistant buildings, facilities, and critical infrastructure systems

• Blast, shock, impact, and penetration event characterization

• Development and validation of the Dynamic Structural Analysis Suite (DSAS) computer program

• Damage assessment before and after explosive incidents

• Fortifications and force protection measures, including lightweight blast and fragment shields, modular systems, and shock isolation

• Hurricane wind effects on structural systems — numerical and experimental simulations

• Multi-hazard considerations for facility protection

• Precision impact testing

• Progressive collapse

• Structural connections under blast and shock • Thermodynamic blast suppression • Ultra-High-Performance Concrete applications for protective structures • Wind-driven rain and/or debris effects on structural systems • Training in protective technology

Technical Activity Areas

CIPPS staff are involved in training on protective structures through short courses and workshops. The following five graduate-level courses on protective structures have been developed:

Protective Structures This course is aimed at understanding the loading phenomena associated with the effects of conventional and nuclear explosive devices, and the structural response to such loads. Dynamic analysis and design approaches for a wide range of structural systems and materials to mitigate such effects are addressed, as are the behavior and design of structural connections, non-structural sys-tems, and progressive collapse. Load-impulse (P-I) diagrams for structural behavior and damage assessment are discussed to ad-dress a wide range of applications.

Advanced Protective Structures This course addresses the planning, security assessment, and technical issues involved with mitigating the severe effects associated with explosive incidents (e.g., blast, shock, impact, etc.). It is focused on the advanced treatment of threat and hazard assessment, as well as mitigation approaches when considering conventional, nuclear, industrial, and terrorism hazards. Some of the addressed topics include characteristics of explosive devices and environments, including improvised explosive devices (IED); combined effects (e.g., blast-fragment and medium-structure interaction effects); protective planning and design philosophy; advanced structural dy-namic analysis and structural behavior; advanced treatment and derivation of P-I diagrams; implementation of engineering, architec-tural, safety, and security considerations; application of innovative materials to protective design; and damage assessment, evacua-tion, rescue, and recovery.

Academic Courses and Training

CENTER FOR INFRASTRUCTURE PROTECTION AND PHYSICAL SECURITY PAGE 6

Sponsored Research • Physics-Based Ultra-High-Performance Concrete Research, Defense Threat Reduction Agency, 2009 • Coupled Size and Rate Effects in Ultra-High-Performance Concrete, Ministry of Defense, Israel, 2012 • CIPPS participates in Data Exchange Agreements on Ultra-High-Performance Concrete R&D with Switzerland, France, and Israel • Other collaborative R&D agreements are under development with defense organizations in Canada, Germany, Japan, Singapore,

South Korea, and the United Kingdom

Critical Infrastructure Protection Certificate (CIPC)

The Civil and Coastal Engineering (CCE) Department, an academic unit of the Engineering School of Sustainable Infrastructure and Environment (ESSIE), has established a Critical Infrastructure Protection Certificate (CIPC) program that was approved by the Uni-versity’s Graduate Council for graduate students with interests in the area of protecting the Nation’s critical infrastructure systems against blast, shock, and impact incidents. This is a nine-credit program, compatible with the decision by the College of Engineering (COE) to select security and critical infrastructure protection as one of its focus areas. CIPPS, established at the University of Florida in 2006, provides a solid foundation for the proposed focus area in the College of Engineering and the CIPC program.

The CIPC program was formulated to meet the education needs of a diverse group of students, while working within the current CCE curriculum to optimize the delivery of education and faculty resources. It is further anticipated that offering this Certificate will strengthen relationships between the COE, the government, and industry sectors, and will help to increase enrollment in both the MS and PhD programs through graduate “program ambassadors.” Furthermore, it is envisioned that this new program will create new research and development funding opportunities and enhanced job placement for COE graduate and undergraduate students. The Certificate is awarded to participants upon the completion of their graduate degree studies.

Participants in the CIPC program can select three courses* from the list below: • Introduction to Protective Structures (required of all participants) • Advanced Protective Structures • Retrofit Methods for Protective Structures • Applied Protective Technology • Impact Engineering *Typically, graduate students involved with the research and development activities at CIPPS take all five courses.

The prerequisites for program participation are: A BS degree in civil engineering with a specialization in structures Must be a graduate degree seeking student Completion of CES 6108 – Structural Dynamics

Retrofit Methods for Protective Structures This course addresses the threat and risk assessments of existing structural facilities under explosive loading effects. Topics include damage prediction of various structural elements under explosive loads, applications of P-I approaches for accurate and expedient assessments of retrofit options, and the development of retrofit strategies to mitigate anticipated damage. Comparison of pre- and post-retrofit performance in assessing risk remediation are also included in the course activities.

Applied Protective Technology This course discusses sound protective technology approaches and procedures under emergency conditions, when expedient ac-tion is required in urban and field settings. The topics include application assessment of procedures for threat and hazard definition, load definition, facility response and consequence assessment, P-I approaches for accurate and expedient assessments, expedient remediation procedures and their assessment, and expeditionary and modular force protection approaches.

Impact Engineering This course is aimed at understanding elastic and plastic behavior of beams and plates under concentrated and distributed impact loads. Some of the topics addressed include limit states, plastic hinge and/or yield line formation, and comparisons of closed-form solutions with fast-running approximate solutions and advanced numerical solutions for cases tested under precision impact condi-tions.

Academic Courses and Training (Cont.)


Preparation for New Testing Efforts

New normal-strength concrete (NSC) and ultra-high-performance concrete (UHPC) test specimens were constructed between De-cember 2012 and February 2013. Upon the completion of the steel reinforcing cages, forms, and strain gage application, they were shipped to the U.S. Army Engineer Research and Development Center (ERDC), in Vicksburg, MS, for pouring and curing. The new beam specimens (Figure 1) will provide greater details on the behavior in the compression zone of the beams and on the perfor-mance of beams with increasing tensile reinforcement. The new shear specimens (Figure 2) will provide a second specimen size, which will give additional insight into any size effects that might exist for these specimens. Figure 3 shows the UHPC specimens after being poured. We acknowledge, with gratitude, the very supportive role that the ERDC technical staff had in this activity.

Figure 1: Beam forms and steel cages

Figure 2: Shear forms and rebar cages before pour

Figure 3: UHPC specimens

Examples of Research & Development


Examples of Research & Development Dynamic Structural Analysis Suite (DSAS) Update

Currently, DSAS 4.1 is undergoing a final stage of testing before it is released. This version incorporates a new material model for steel and offers improved accuracy in the analysis of UHPC structural members compared to the current version (4.0.7). Aside from these additions and improvements, this update provides bug fixes and user interface improvements. Below are the comparisons between the load deformation curves obtained by the testing of UHPC beams and results obtained from DSAS 4.1. In both of the cases shown below, the test beams were constructed using UHPC (f’c > 30 ksi). Both beams had conven-tional longitudinal and transverse reinforcement and were tested under point loads applied at midspan. The UHPC beam in Case 1 had steel fibers in the concrete matrix, whereas the beam in Case 2 did not have any fibers and relied solely on conventional rein-forcement. In either case, there was a good correlation between the test results and the numerical results obtained using DSAS.

Case 1: UHPC beam with fibers.

Case 2: UHPC beam with w/o fibers.

CENTER FOR INFRASTRUCTURE PROTECTION AND PHYSICAL SECURITY (CIPPS) PAGE 9

Figure 2 : UHPC beam B3 with full Reinforcement

Figure 3 : UHPC beam B5 without Reinforcement

Figure 4: UHPC beam B6 with longitudinal bars but no stirrups

Examples of Research & Development Characterization and Numerical Implementation of Constitutive Material Model for Ultra-High-Performance Concrete Experimental data from cylinders and beam tests conducted at CIPPS were processed and used in the characterization of material model parameters for numerical simulations. The Concrete Damage Plasticity (CDP) material model was used for normal-strength concrete (NSC) and ultra-high-performance concrete (UHPC) simulations using the finite element program ABAQUS. Typical simula-tion cases and comparisons are shown in Figures 1 through 4.

Figure 1: NSC and UHPC beam models with all reinforcements

CENTER FOR INFRASTRUCTURE PROTECTION AND PHYSICAL SECURITY (CIPPS)

Congratulations!

• To Melvin Goh and his family on the arrival of their baby boy and on Melvin’s recent successful Master’s Thesis Presentation.

• To Michael Stone on his successful Master’s Thesis Presentation and his Graduate Fellowship to enter the PhD pro-

gram at UF. • To Daniel Koch for his new job opportunity with Sargent & Lundy. Daniel will be moving to Chicago to begin his ca-

reer in April. New Employees

Welcome to Rebecca (Corey) Astrom. Corey joined the CIPPS Group in November 2012 as the Technical Editor. She will work with the UHPC Project to review/edit all documents and reports.

Upcoming Events

• Modern Protective Structures Conference— June 15th – 19th, 2013 in Arlington, VA. For more informa on or to register for the conference please visit our web site at: http://conferences.dce.ufl.edu/mps/

• 15th ISIEMS—The 15th International Symposium on the "Interaction of the Effects of Munitions with Structure" will be held in

Potsdam, Germany, September 17th – 20th, 2013: www.15isiems.com or www.isiems.de

Announcements

Our Mission University of Florida and the Center for Infrastructure Protection and Physical Security (CIPPS), The primary mission of CIPPS is to establish comprehensive short- and long-term research and development activities in protec-tive science and technology. Our goal is to ensure the safety of personnel and facilities under explosively induced hazards and evolving threats.

At CIPPS, we put special emphasis on civil and structural engineering, computational mechanics and dynamics, and the behavior of structural systems under severe loading environments.

These activities are handled by an experienced multidisciplinary technical and scientific staff that includes engineers and scientists with advanced academic degrees in several engineering disciplines. CIPPS personnel are guided by Dr. Theodor Krauthammer, Goldsby Professor of Civil Engineering at the University of Florida, who has more than 35 years of engineering and scientific expe-rience in the areas of physical security and mitigation of blast, shock, and impact effects.

During the last few months, we have continued to work on exciting multi-year projects (see Sponsored Research on page 4), and we are currently working with several other potential sponsors from various government agencies and the private sector. Also, we continue to expand our team with new faculty, students, and staff.

One of our key focus areas is to transfer technology through education, training, technical advising, and collaborative research and development.


MODERN PROTECTIVE STRUCTURES

Short Course Arlington, Virginia, July 15–19, 2013

Sponsored by the University of Florida and the Center for Infrastructure Protection and Physical Security (CIPPS), and endorsed by the Society of American Military Engineers (SAME) and The Infrastructure Security Partnership (TISP)

Terrorism is not a new phenomenon, and one can find historic references that such activities have existed for more than 2,000 years. Many regions around the world have been increasingly burdened by terrorism and other types of warfare during the last quarter century (e.g., Afghanistan, Columbia, France, Germany, Greece, India, Iraq, Israel, Italy, Japan, Mexico, Russia, Spain, Sri Lanka, United Kingdom, United States, and many more). Historical terrorism activity data indicates that more than 90% of rec-orded incidents involved explosive devices or ballistic attacks. Vehicle bombs and other types of improvised explosive devices (IEDs) have become the preferred mechanism for terrorist attacks, followed by the use of homicide bombers and the renewed threat of weapons of mass destruction (WMD). Defending society against this rapidly evolving type of warfare will remain a chal-lenge throughout the 21st century. Any successful response will require a well-planned, multilayered approach that strikes a fine balance between assuring a nation’s security and maintaining the freedoms that modern societies enjoy. Technology can and will play a major role in these efforts, and society must develop innovative and comprehensive protective technologies. Did you have special training in designing a building or facility that can protect people and/or assets from such incidents? With all of the regulations and guidelines you must currently follow, you now have to also consider how to protect from an explosive at-tack. The key to achieving such objectives is knowledge — what exists and what can be done regarding various evolving threats. Modern Protective Structures is a short course based on a graduate-level, semester-long course at the University of Florida. It is one of five graduate-level courses that have been developed by Prof. Ted Krauthammer to educate and train the next generation of scientists and engineers to work in this vital and challenging field. This short course has been modified every year to include new material, and it is aimed at addressing a broad range of scientific and technical issues involved in mitigating the severe load-ing effects associated with blast, shock, and impact. Past participants, who represent an international cross section of public and private organizations, have told us that the hands-on, problem-based approach has provided them with valuable and practical knowledge that they can incorporate effectively and immediately into their work. Architects, engineers, and safety and security managers will have the opportunity to:

• Learn how to assess the risk associated with threats, hazards, and various explosive incidents • Have access to knowledge on how such facilities (e.g., office buildings, schools, airports, hospitals, power stations, and in-

dustrial and transportation infrastructure facilities and systems) behave under blast, shock, and impact loads • Learn how to analyze and design various facilities to protect lives and property • Study and practice how to implement such knowledge for conducting effective pre- and post-event facility assessments, res-

cue and recovery operations, and forensic investigations

Prof. Ted Krauthammer will be instructing the Modern Protective Structures short course in Arlington, Virginia, from Monday, July 15 through Friday, July 19, 2013. We invite you and your colleagues to register for this course. Please visit the link: http://conferences.dce.ufl.edu/mps/ to view information on the course location, accommodations, and registration.

Seminars & Conferences

Our Sponsors CIPPS is recognized internationally and its activities have been supported by various government agencies in the U.S. and abroad.

The University of Florida 2114 NE Waldo Road

PO Box 116580 Gainesville, FL 32609

Center for Infrastructure Protection and Physical

Security (CIPPS)

Phone: 352-273-0690 Fax: 352-273-0186

E-mail: [email protected]

Visit us at: www.cipps.eng.ufl.edu

CIPPS is currently seeking high-quality candidates for Post-Doc and Research Assistant positions with documented experience in impact testing of structural concrete elements. Interested individuals should contact us for further information (U.S. citizens preferred).

New Activity Multi-Hazard Mitigation After a very successful NATO-sponsored workshop on Urban Structures Resilience under Multi-Hazard Threat, Moscow, Russia, July 16–18, 2007, CIPPS continues to work with colleagues from the hurricane research facility at UF, and from the Universi-ty of the Armed Forces in Germany, on developing our innovative multi-hazard mitiga-tion approach.

Available Positions


center for infrastructure protection and physical...

Documents