TY - CONF A1 - Agasty, Amit A1 - Hering, Marcus T1 - Eine Machbarkeitsstudie zur Skalierung von Sprengversuchen an Stahlbetonbauteilen N2 - Sprengversuche sind erforderlich, um Explosionsereignisse auf Grund von Unfällen oder Anschlägen zu untersuchen und um das Schutzniveau für Menschen und Anlagen in kritischen Infrastrukturen zu bewerten. Die Durchführung von Feldversuchen in großem Maßstab für komplexe Szenarien ist sehr ressourcenintensiv. Verlässliche Experimente im kleinen Maßstab sind eine vielversprechende Alternative. Die Skalierungsgesetze für die Bemessung von Stahlbetonkonstruktionen unter Explosionsbelastung sind jedoch nicht hinreichend etabliert. Die Forschungsarbeit fokussiert sich auf Stahlbetonstrukturen, die für die Standardisierung von skalierten Sprengversuchen in Frage kommen. Im Rahmen der Machbarkeitsstudie wurden auf dem TTS-Gelände Sprengversuche an Probekörpern unterschiedlicher Größe durchgeführt. Dabei wurden verschiedene horizontal gelagerte Stahlbetonplatten getestet und unterschiedlichen Explosionsbelastungen ausgesetzt. Die Sprengversuche umfassten verschiedene Messtechniken zur Quantifizierung der Explosionslast sowie des Verhaltens der Stahlbetonplatten. Die Explosionslast wurde mit bündig eingebauten piezoelektrischen Druckmessern gemessen, während Beschleunigungssensoren und flächig applizierte verteilte faseroptische Sensorik verwendet wurden, um das dynamische Verhalten der Platte unter Explosionsbelastung zu charakterisieren. Darüber hinaus wurden Schädigungsmerkmale ebenfalls mit verteilter faseroptischer Sensorik ermittelt. Die Anwendung solcher Messtechniken sowie die Nutzung verschiedener numerischer Softwaretools bieten die Möglichkeit die Skalierungsgesetze zu verifizieren bzw. anzupassen. T2 - BBK - Fachkongress Forschung für den Bevölkerungsschutz 2025 CY - Bonn, Germany DA - 05.02.2025 KW - Sprengversuch KW - Skalierung KW - Faseroptik PY - 2025 AN - OPUS4-62509 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus A1 - Agasty, Amit A1 - Costard, René A1 - Hüsken, Götz A1 - Chruscicki, Sebastian A1 - Hicke, Konstantin T1 - Explosion effects on reinforced concrete structures – A preliminary study of scaling laws N2 - Blast tests are required to investigate accidental or intentional blast events and to assess the level of protection for people and facilities in critical infrastructures. Conducting large-scale field tests for complex scenarios is very resource intensive. Reliable small-scale experiments are a promising alternative. However, the scaling laws for the design of reinforced concrete structures under blast loads are not sufficiently established. In our research work, a consortium made up of three BAM departments, focuses on reinforced concrete structures that are suitable for the standardization of scaled blast tests. As part of the feasibility study, blast tests were carried out on test specimens of different sizes on the BAM Test Site for Technical Safety (TTS). Various reinforced concrete plates were tested and subjected to different blast loads. The blast tests included various measurement techniques to quantify the blast load and the behavior of the reinforced concrete plate. The blast load was measured with flush-mounted piezoelectric pressure gauges, while accelerometers and embedded fiber optic sensor cables were used to characterize the dynamic behavior of the plate under blast loading. In addition, damage characteristics were also determined using distributed fiber optic sensing. The application of these measurement techniques as well as the use of different numerical software tools offer the possibility to verify or adapt the scaling laws. T2 - 19th International Symposium on Interaction of the Effects of Munitions with Structures (19th ISIEMS) CY - Bonn, Germany DA - 09.12.2024 KW - Scaling KW - Blast KW - Fiber optic sensing PY - 2024 SP - 1 EP - 9 AN - OPUS4-62258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Replica scaling of RC slabs under blast loading: a preliminary assessment N2 - Blast testing is undoubtedly the most straightforward and direct method of evaluating the blast resistance of a structure. For the calibration and validation of numerical models as well, blast tests must be carried out. However, true-scale prototype testing under different blast loading scenarios is not always feasible. Reliable small-scale experiments are a promising alternative. Application of dimensional analysis and similarity principals can be found in different engineering fields. For applications to the phenomenon of shock wave propagation, Hopkinson-Cranz or cube-root scaling is a well-established concept. When it comes to the scaling the structural response, research has predominantly focused on structures made of metallic materials. Scaled investigations with concrete or reinforced concrete (RC) structures remain limited, specifically under blast loading. In a preliminary study, we tested RC slabs at two different scales under near-field blast loading. Replica scaling, which is geometrical scaling while using the same materials at different scales, was implemented in the construction of the test specimens. The assessment of scaling and the discrepancy in its application was investigated by characterizing the blast loads, dynamic response, and damage. The experiments were supplemented by numerical simulations of these scenarios. The quantification of scenario-and-response-specific discrepancy can be used to modify the scaling laws, so that a blast assessment can be performed based on resource efficient small-scale tests. T2 - 25th International Physical Security Forum CY - Schwarzenburg, Switzerland DA - 11.05.2025 KW - Blast KW - RC slabs KW - Scaling PY - 2025 AN - OPUS4-63184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit A1 - Hering, Marcus T1 - Experimental and Numerical Analysis of Reinforced Concrete Structures Under Blast Loading: Scopes and Challenges N2 - Protection against terrorist or accidental scenarios in industrial settings requires suitable designs of structures to resist blast loads. Field testing as well as finite element simulations are among the techniques available to engineers in the understanding of the structural behavior against blast loading. As blast testing of complex scenarios can be very resource intensive, tests are generally performed for simplified scenarios. Numerical tools can be used to model these scenarios in order to get a better insight into blast loading, structural response and the resulting damage to the structure. In the next steps, the simplified scenario is successively modified in numerical simulations to incorporate complexities that cannot be covered in blast testing experiments. One of the conditions for this approach to work is that the original simplified numerical simulation is valid. The scopes and challenges encountered in such a validation are the focus of this presentation. A relatively ‘simple’ field test of a horizontal reinforced concrete (RC) slab subjected to blast loading is taken as an example for validation of the performance of numerical tools. The blast test incorporated various measurement techniques to quantify the blast load as well as the behavior of the RC slab. Blast load was measured using flush-mounted piezoelectric pressure gauges, whereas acceleration sensors and fiber-optic sensor cables were used to characterize the dynamic behavior of the slab under blast loading. Additionally, damage characteristics were ascertained also using fiber-optic sensing. The application of such measurement techniques, along with different numerical software available for the analysis of the scenario in question, demonstrate the scope of our contribution. T2 - 24th International Physical Security Forum Brussels CY - Brussels, Belgium DA - 15.04.2024 KW - Blast KW - Reinforced Concrete Structures KW - Numerical simulations PY - 2024 AN - OPUS4-60880 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Structural behavior and damage assessment of a reinforced concrete wall by various NDT methods and embedded sensors under blast-loading N2 - A safety or security related assessment of explosions, accidental and intentional scenarios alike, often necessitate performance of replication-tests. Such test results are necessary to clarify the causes within the scope of forensic investigations. To gain important insights into the behavior of structures and materials under such loading, field tests may also be performed in accordance with different test standards. To determine the resistance of building-structures after explosions, estimation of the residual load-bearing capacity in addition to the assessment of dynamic structural response and damage to the building components is important. In most cases an evaluation of structural integrity is based only on the visual damage, resulting in an overestimation of the residual capacity. The Bundesanstalt für Materialforschung und -prüfung (BAM) operates the Test site for Technical Safety (TTS) on an area measuring about 12 km2 in the Federal State of Brandenburg for execution of true-to-scale explosion tests. At the TTS, building component testing was performed to assess the suitability of different non-destructive testing methods to characterize the dynamic structural response and damage resulting from the detonation of high explosives. Different blast-loading scenarios were realized by varying the net explosive mass and the standoff distance with all scenarios representing a near-field detonation. The test object was a reinforced concrete wall 2 m high, 2.5 m wide and 20 cm thick, fixed at both vertical edges. The dynamic loading of the wall was characterized with 8 piezoelectric pressure sensors flush-mounted on the front surface, thus measuring the reflected pressures from the shock wave. The tests were conducted with the aim of characterizing the global behavior of the wall under dynamic shock loading and the resulting local damage pattern, respectively. High speed digital image correlation was implemented in combination with multiple acceleration sensors to observe the rear surface of the wall to chart the dynamic deflection during the loading and to determine the residual deformation after the loading had ceased. In addition, one test specimen was instrumented with fiber optic sensor cables, both fixed to the rebars and embedded in the concrete-matrix, respectively. Firstly, these sensors were interrogated during the blast test by a distributed acoustic sensing (DAS) device using a particularly high sampling rate to measure the shock-induced vibrations in the structure with high temporal resolution. This delivers information on dynamics of compression and tension cycles from within the structure. Secondly, the local damage-pattern emerging during the series of blasts was determined via distributed fiber optic strain sensing (DSS) by interrogating the embedded fiber optic sensors with a high spatial resolution DSS device after each blast. This enabled the characterization of non-visual damage to the structure, in particular with regard to the formation of localized cracks in the concrete matrix. The DSS was further complimented by a structure-scanner based on ultrasonic measurements. Our contribution describes this new test approach in detail. Results of the three datasets, namely dynamic shock loading, global behavior of the test object and the local damage pattern will be presented. The suitability of the implemented measurement methods will be discussed in combination with the challenges in their application for technical safety evaluation of building components under explosive loading. T2 - 26th International Symposium on Military Aspects of Blast and Shock (MABS26) CY - Wollongong, Australia DA - 03.12.2023 KW - Blast tests KW - Reflected pressure KW - Embedded sensors KW - Distributed fiber optic sensors KW - Acceleration sensors KW - Digital image correlation KW - Ultrasonic structure-scanner PY - 2023 AN - OPUS4-58927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - A Preliminary Study on the Scaling of RC Structures under Blasting Loading N2 - Current capabilities for full-scale field blast testing are highly resource intensive. Reliable small-scale experiments are an effective alternative. Characterization of the dynamic response and damage of RC elements to scaled blast loads was investigated in scaled-down field experiments. Spatially resolved information on the dynamic structural response to blast loading was obtained using distributed fiber optic acoustic sensing (DAS), acceleration sensors as well as piezoelectric pressure sensors. T2 - 46. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 25.04.2025 KW - Explosives KW - Blast and scaling effects KW - Concrete PY - 2025 AN - OPUS4-62994 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Numerical analysis of structures under blast loading N2 - Blast tests are indispensable for investigations of accidental or intentional explosions and to evaluate the level of protection to people and equipment within critical infrastructure. Current capabilities for detailed blast effects assessment are limited to performing full-scale field testing, which, for complex scenarios, are highly resource intensive. In this regard, reliable numerical simulations are an effective alternative option. A discussion of the scope and challenges of using numerical tools for a technical-safety assessment of reinforced concrete structures under blast loading is presented. Different coupling possibilities between shock wave simulations and structural simulations with the help of practical examples is given. An outlook on the development of new methods for structural simulations currently being researched at BAM concludes the presentation. T2 - Exerter Final Conference, 2023 CY - Soest, The Netherlands DA - 24.04.2023 KW - Coupling KW - Numerical Simulation KW - Blast KW - Structural Analysis KW - FSI PY - 2023 AN - OPUS4-57458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Costard, René A1 - Agasty, Amit A1 - Kadoke, Daniel A1 - Kind, Thomas A1 - Hicke, Konstantin A1 - Hüsken, Götz T1 - Charakterisierung der Belastung und Schädigung von Stahlbetonprüfkörpern unter Explosionsbeanspruchung N2 - Zur Bewertung der Widerstandsfähigkeit von Schutzobjekten und Bauteilen gegen Explosionsbeanspruchung führt die Bundesanstalt für Materialforschung und -prüfung (BAM) regelmäßig Sprengversuche im Realmaßstab auf einem Testgelände durch. Solche Versuche sind planungs- und ressourcenintensiv, sodass sie zunehmend durch numerische Simulationen ergänzt bzw. ersetzt werden. Aktuelle Forschungsarbeiten zielen darauf ab, neue Berechnungsmethoden und Materialmodelle zu entwickeln, mit denen die Bestimmung der Bauteilantwort sowie die daraus resultierende Schädigung nach einem Explosionsereignis möglich sind. Zur Validierung solcher Ansätze ist es notwendig, systematische Versuche mit unterschiedlichen Szenarien durchzuführen, bei denen die relevanten Parameter mit Hilfe verschiedener Messmethoden aufgezeichnet werden. T2 - 44. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 14.04.2023 KW - Explosivstoff KW - Explosionswirkung KW - Stahlbeton KW - Faseroptische Sensorik PY - 2023 SN - 0941 - 4584 VL - 45 IS - 2 SP - 11 EP - 14 AN - OPUS4-58109 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hicke, Konstantin A1 - Chruscicki, Sebastian A1 - Breithaupt, Mathias A1 - Costard, René A1 - Kind, Thomas A1 - Hüsken, Götz A1 - Agasty, Amit T1 - Measuring Dynamic Behavior and Damage Evolution of a Reinforced Concrete Wall Subjected to Explosive Blasts using Embedded Distributed Fiber Optic Sensors N2 - Results from highly dynamic and static strain measurements, respectively, using embedded distributed fiber optic sensors in a steel-reinforced concrete wall under explosive blast-loading are presented, detailing the structure’s dynamic behavior and the evolutions of cracks. T2 - 28th International Conference on Optical Fiber Sensors (OFS-28) CY - Hamamatsu, Japan DA - 20.11.2023 KW - Distributed acoustic sensing KW - DAS KW - Structural response KW - Blast experiment KW - Embedded fiber optic sensor PY - 2023 SP - 1 EP - 4 PB - Optica CY - Washington D.C., USA AN - OPUS4-59096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit A1 - Costard, René T1 - Dynamic response of reinforced concrete (RC) components in scaled-down blast tests N2 - Current capabilities for full-scale field testing are highly resource intensive. Reliable small-scale experiments are an effective alternative. Characterization of the dynamic response and damage of RC elements to scaled blast loads was investigated in scaled-down field experiments. Spatially resolved information on the dynamic structural response using distributed fiber optic acoustic sensing (DAS) and acceleration as well as blast loading by piezoelectric pressure sensors. T2 - 45. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 05.04.2024 KW - Blast tests KW - Reinforced concrete KW - Acceleration sensors PY - 2024 AN - OPUS4-59808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Assessment of the Application of Scaling Concepts for Blast Effects Analysis N2 - Blast testing finds its implementation in several applications, e.g. for the purpose of investigation into accidental or intentional explosions, or for an assessment of the level of protection provided by a certain structural configuration. Analytical and/or semi-empirical methods are generally limited to preliminary assessments prior to blast testing. Applications of numerical simulations with hydrocodes coupled with finite element methods (FEM) can only reduce the amount of blast testing required, as these necessitate fulfillment of the fundamental prerequisites of model verification and that of model validation. Field tests are implemented for contact detonations as well as near-field blast scenarios and shock tube tests for far-field blast scenarios. However, these can be extremely resource intensive. Reliable small-scale experiments are a promising alternative. The concepts of dimensional analysis and similarity based on Buckingham’s Π-theorem (1914) have been applied in different fields. For applications to the phenomenon of shock wave propagation, Hopkinson-Cranz or cube-root scaling is a well-established concept. When it comes to scaling the structural response, research has predominantly focused on structures made of metallic materials. Scaled investigations with concrete or reinforced concrete (RC) structures remain limited. The lack of even the most basic guidelines (far from any ‘standardized scaling methods’ for blast tests) show that scaling as a method is not yet established in blast effects analysis. In this preliminary study, we present a systematic approach and evaluation of scaling of blast effects analysis for RC slabs in order to develop guidelines for resource efficient testing methods. We study the blast scenario at two different scales. The focus of these investigations has been on evaluation of scaling of dynamics using pressure sensors, acceleration sensors and fiber optic sensing cables for distributed acoustic sensing (DAS). Further, the resulting plastic behavior upon blast is characterized by distributed strain sensing (DSS) along the same cables. T2 - 27th International Symposium on Military Aspects of Blast and Shock (MABS27) CY - Colmar, France DA - 06.10.2025 KW - Blast KW - RC-slabs KW - Similarity and scaling PY - 2025 AN - OPUS4-64616 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit A1 - Costard, Rene A1 - Hering, Marcus A1 - Chruscicki, Sebastian A1 - Hicke, Konstantin A1 - Hüsken, Götz T1 - Assessment of the Application of Scaling Concepts for Blast Effects Analysis N2 - Blast testing finds its implementation in several applications, e.g. for the purpose of investigation into accidental or intentional explosions, or for an assessment of the level of protection provided by a certain structural configuration. Analytical and/or semi-empirical methods are generally limited to preliminary assessments prior to blast testing. Applications of numerical simulations with hydrocodes coupled with finite element methods (FEM) can only reduce the amount of blast testing required, as these necessitate fulfillment of the fundamental prerequisites of model verification and that of model validation. Field tests are implemented for contact detonations as well as near-field blast scenarios and shock tube tests for far-field blast scenarios. However, these can be extremely resource intensive. Reliable small-scale experiments are a promising alternative. The concepts of dimensional analysis and similarity based on Buckingham’s Π-theorem (1914) have been applied in different fields. For applications to the phenomenon of shock wave propagation, Hopkinson-Cranz or cube-root scaling is a well-established concept. When it comes to scaling the structural response, research has predominantly focused on structures made of metallic materials. Scaled investigations with concrete or reinforced concrete (RC) structures remain limited. The lack of even the most basic guidelines (far from any ‘standardized scaling methods’ for blast tests) show that scaling as a method is not yet established in blast effects analysis. In this preliminary study, we present a systematic approach and evaluation of scaling of blast effects analysis for RC slabs in order to develop guidelines for resource efficient testing methods. We study the blast scenario at two different scales. The focus of these investigations has been on evaluation of scaling of dynamics using pressure sensors, acceleration sensors and fiber optic sensing cables for distributed acoustic sensing (DAS). Further, the resulting plastic behavior upon blast is characterized by distributed strain sensing (DSS) along the same cables. T2 - 27th International Symposium on Military Aspects of Blast and Shock (MABS27) CY - Colmar, France DA - 06.10.2025 KW - Similarity and scaling KW - Blast KW - RC-slabs PY - 2025 SP - 1 EP - 11 AN - OPUS4-64617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Skalierung von Sprengversuchen N2 - Eine Machbarkeitsstudie zur ressourceneffizienten sicherheitstechnischen Bewertung. T2 - 25. Internationalen Symposium des Bundeskriminalamtes für Sprengstoffermittelnde und Entschärfende unkonventioneller Spreng- und Brandvorrichtungen CY - Magdeburg, Germany DA - 01.12.2025 KW - Sicherheitstechnische Bewertung KW - Sprengversuche KW - Skalierung KW - Numerische Simulationen PY - 2025 AN - OPUS4-65019 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Agasty, Amit A1 - Costard, Rene A1 - Kadoke, Daniel A1 - Kind, Thomas A1 - Hicke, Konstantin A1 - Hüsken, Götz T1 - A comprehensive experimental assessment of reinforced concrete walls under blast: In situ monitoring of loading, dynamic response and damage with NDT methods and embedded sensors N2 - A safety or security related assessment of explosions, accidental and intentional scenarios alike, often necessitate performance of resource intensive replication tests. For an efficient assessment without performing full scale blast tests, e.g., supported by numerical simulations, detailed knowledge is necessary to predict the blast loading from a given charge configuration, the resulting dynamic response of the structure under investigation as well as the resulting damage. Validation of numerical simulation requires the spatially resolved acquisition of all these parameters in real time. In this paper we present a set of measurement techniques and discuss their suitability for monitoring reinforced concrete (RC) walls under blast loading. Different blast-loading scenarios were realized by varying the charge weight and the standoff distance. The dynamic loading of the wall was characterized with pressure sensors complemented by numerical simulations using the APOLLO Blastsimulator and ConWep. High speed digital image correlation (DIC) was implemented in combination with multiple acceleration sensors to observe the dynamic deflection of the walls during the loading and to determine the residual deformation after the loading had ceased. In addition, one test specimen was instrumented with fiber optic sensor cables. These fiber optic sensors were used for distributed acoustic sensing (DAS) delivering information on dynamics of compression and tension cycles from within the structure. Additionally, the local damage pattern emerging during the series of blasts was determined via distributed fiber optic strain sensing (DSS) to enable the characterization of visual and non-visual damage to the structure. The obtained information was compared to results by an ultrasound structure-scanner. KW - Blast testing KW - Reinforced concrete KW - NDT methods KW - Fiber optic sensing KW - DIC KW - Numerical simulations KW - APOLLO Blastsimulator PY - 2025 DO - https://doi.org/10.1177/20414196251353795 SN - 2041-4196 SP - 1 EP - 31 PB - Sage Publications AN - OPUS4-63832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -