Fragility analysis, IM = Scaled distance (Part 1)

Performance-based blast engineering

The Blast Blind Simulation Contest 2012

The Blast Blind Simulation Contest 2012

http://sce.umkc.edu/blast-prediction-contest/

 

The Finite Element model

The results - Mid-span deflection

Insulated panel subjected to a close-in detonation

Numerical simulation of insulated panels subjected to close-in detonations

Timeline (2010 - 2013)

Curriculum Vitae

--> Curriculum Vitae download <--

Journal papers

Olmati P, Petrini F, Gkoumas K. Fragility analysis for the Performance-Based Design of cladding wall panels subjected to blast load. Engineering Structures - SP; in press.

Olmati P, Petrini F, Vamvatsikos D, Gantes CJ. Safety factor and fragility analysis for structures subjected to explosions: the case of steel built-up blast resistant doors. Ongoing. 

Olmati P, Trasborg P, Naito CJ, Sgambi L, Bontempi F. Modeling the response of concrete slabs under blast loading. ACI Structural Journal - SP; submitted.

Giovino G, Olmati P, Garbati S, Bontempi F. Blast resistance assessment of concrete wall panels: experimental and numerical investigations. International Journal of Protective Structures; submitted. 

 Naito C, Olmati P, Trasborg P, Davidson J, Newberry C. Assessment of insulated concrete walls to close-in blast demands. Journal of Performance of Constructed Facilities; in press. 

 Trasborg P, Nickerson J, Naito C, Olmati P, Davidson J. Forming a predictable flexural mechanism in reinforced wall elements. ACI Structural Journal; submitted.

Olmati P, Trasborg P, Naito CJ, Bontempi F. Blast resistant design of precast reinforced concrete walls for strategic infrastructures under uncertainty. International Journal of Critical Infrastructures 2014; in press.

Olmati P, Gkoumas K, Brando F, Cao L. Consequence-based robustness assessment of a steel truss bridge. Steel and Composite Structures 2013; 14(4): 379-395.

Olmati P, Petrini F, Bontempi F. Numerical analyses for the structural assessment of steel buildings under explosions. Structural Engineering and Mechanics 2013; 45(6): 803-819.

Olmati P. Simulazione di esplosioni e metodologie progettuali per la mitigazione del rischio associato. Costruzioni Metalliche 2012; 1: 59-60.

Research records - Until the Ph.D. degree

I began the three years Ph.D. program in Structural Engineering in November 2010.  During the first year of the Ph.D. program I focused on the behavior of buildings subjected to severe structural damages like the loss of one or more columns at the ground floor due to accidental or man-made explosions (for an example of such events, see the collapse of the Ronan Point tower - 16 May 1968).  A procedure to evaluate the capacity of a structural system (e.g. building) to withstand structural damages (structural robustness) is proposed in a first publication together with a study on the simulation of gas explosions (for an example of such events, see the case of Buncefield, London - 11 December 2005): "Olmati P, Petrini F, Bontempi F. Numerical analyses for the structural assessment of steel buildings under explosions. Structural Engineering and Mechanics 2013; 45(6): 803-819".  A second publication regards the structural robustness of steel truss bridges (see the collapse of the I-35W Minneapolis Bridge): "Olmati P, Gkoumas K, Brando F, Cao L. Consequence-based robustness assessment of a steel truss bridge. Steel and Composite Structures 2013; 14(4): 379-395". 

During the second year I spent five months (from February 2012 to July 2012) at the Lehigh University (Bethlehem, PA, USA) under the supervision of Prof. Clay Naito, performing research on the performance assessment of insulated panels subjected to close-in detonations.  Detailed numerical simulations (using the LS-Dyna software) were carried out in order to assess the advantages in terms of scabbing and breach resistance of the insulated panels versus the classic concrete panels.  Experimental tests were conducted at the Air Force Research Laboratory in Panama City, FL, USA.  The report of the experimental test is being approved for the "Statement A - for public realize and unlimited distribution" following the rules of the United State Department of Defense for being published. 

In the autumn of 2012 I participated at the "Blast Blind Simulation Contest 2012 - assessment of the deflection of reinforced concrete slabs subjected to a blast demand (http://sce.umkc.edu/blast-prediction-contest)".  The contest was sponsored in collaboration with American Concrete Institute (ACI) Committees 447 (Finite Element of Reinforced Concrete Structures) and 370 (Blast and Impact Load Effects), and UMKC School of Computing and Engineering.  The team was composed by Mr. Olmati (myself), Mr. Trasborg (Lehigh University), Dr. Sgambi (Politecnico di Milano), Prof. Naito (Lehigh University), and Prof. Bontempi (Sapienza University of Rome).  The performed simulation was declared the Winner of the concurring category and the team is invited to publish a paper in a special publication of the American Concrete Institute (ACI) journal. 

During the third year I focused on the probabilistic aspects of the design for blast resistant structures.  In particular, I implemented in blast engineering the probabilistic theory developed in earthquake engineering.  The fragility analysis was carried out for precast concrete cladding wall panels subjected to a terroristic vehicle bomb attack, and the proposed approach was verified and validated by reliability analyses performed by Monte Carlo simulations.  A paper on this study has been accepted for publication: "Olmati P, Trasborg P, Naito CJ, Bontempi F. Blast resistance of reinforced precast concrete walls under uncertainty. International Journal of Critical Infrastructures, 2013".  Moreover a second paper has been submitted to the Structural Safety journal: "Olmati P, Petrini F. Development of fragility curves for cladding panels subjected to blast load". 

The study on the performance-based blast engineering continued at the National Technical University of Athens where I spent about three months (from mid-May to September 2013) under the supervision of Prof. Charis J. Gantes and Prof. Dimitrios Vamvatsikos.  The fragility analysis was carried out for a steel built-up blast resistant door subjected to an accidental explosion of ammunitions, and in a similar manner to the previous studies, the proposed approach was verified and validated by reliability analyses performed by Monte Carlo simulations.  Moreover, a safety factor was provided in order to design the steel built-up door with the common state of the practice method.  The preparation of a journal paper on this topic in ongoing:  "Olmati P, Petrini F, Vamvatsikos D, Gantes CJ. Safety factor and fragility analysis for structures subjected to explosions: the case of steel built-up blast resistant doors". 

In July 2013 I was involved in an experimental test on concrete cladding wall panels subjected to detonation of explosive.  The test was executed at the testing site of the R.W.M. ITALIA s.p.a. (www.rwm-italia.com).  Moreover, detailed numerical simulations were carried out in order to reproduce the experimental evidence.  The work was presented at the 15th International Symposium on Interaction of the Effects of Munitions with Structures (ISIEMS) in Potsdam, Berlin and the journal version of the conference proceeding is ongoing.