This document discusses architectural and structural design techniques for blast resistant buildings. It begins by introducing high explosives and explosion types. Then it describes the explosion process and different types of explosions. On the architectural side, it discusses planning and layout, structural form, internal layout, bomb shelter areas, glazing, and cladding to minimize blast impacts. Structurally, it explains how blast loads affect buildings and the need for ductile and robust beam-column connections to avoid collapse under dynamic loads from explosions. The goal is to provide guidance on mitigating explosion effects to protect human life and building integrity.
Computation of blast loading for a multi storeyed framed buildingeSAT Journals
Abstract
The number and intensity of domestic and international terrorist activities have heightened our concerns towards the safety of our infrastructure systems. Due to different accidental or intentional events, related to important structures all over the world, explosive loads or blast loads have received considerable attention in recent years. The development in this field is made mostly through publication of the U.S. Army Corps of Engineers, Naval Facilities Engineering Command (NAVFAC), and Air Force Civil Engineer Support Agency. In India also, the guidelines for the blast loading are published in IS 4991. In the present study, blast pressures for different weights of surface blast or TNT and varying stand-off distances are computed for a multi-storeyed framed building adopting wave scaling laws given by U.S Army technical manual (UFC3-340-02). Blast pressures for different cases are computed using correlation between blast pressure and blast scaled distance based on charts given in U.S manual. Time history loading is also obtained with parameters of reflected total over pressure and duration of positive phase of blast.
Keywords: blast loading, blast wave, scaled distance, blast pressure.
A brief description on explosion,types of explosion,Physical explosion,details on chemical explosion,types,everything which is needed to understand chemical explosion properly is given here.Case study is also included.
This document discusses wind-induced motion in tall buildings. It begins by explaining the increasing trend of tall building construction globally due to population growth and land scarcity. Tall buildings experience significant lateral loads from wind that can cause dynamic motion, so accurate structural design methods are important. Wind forces on tall buildings are analyzed using wind tunnel tests on scaled models to determine pressures and loads. Vortex shedding is identified as a critical phenomenon that can cause across-wind vibrations if the shedding frequency matches the building's natural frequency. The document provides background on wind characteristics, types of winds, wind speed variation with height, and definitions of high-rise buildings.
FAMAT was founded in 1981 in Saint-Nazaire, France as a joint venture between General Electric and Snecma to manufacture high-tech engine frames and assemblies. It employs 393 people across 25,000 square meters of facilities. FAMAT produces major structural components for commercial aircraft engines made by GE and Snecma that power planes from Airbus, Boeing, and soon Comac.
HappyDev-lite-2016-весна 05 Андрей Юдин. Javascript - мультиинструмент для всехHappyDev-lite
Доклад для тех, кто только выбирает свой путь, ищет куда податься в программировании.
Расскажу о том, что такое JS и что с его помощью можно делать.
Расскажу о использовании JS в браузерах, о его применении на мобильных платформах. О том что с его помощью можно делать десктопные приложения и многое другое.
Spatial data infrastructure in KyrgyzstanUnison Group
The document discusses the limitations of Kyrgyzstan's spatial data infrastructure and the implications for climate adaptation efforts. It finds that there is currently no national SDI, and data exists in silos with poor coordination and data sharing between institutions. This poses challenges for climate adaptation projects that require spatial data on topics like boundaries, satellite imagery, and climate/weather. The document recommends establishing a working group to develop an NSDI through improved data access, standards, and awareness of SDI benefits. This could help adaptation efforts and unlock economic opportunities through increased transparency, efficiency and investment.
Este fresco de la bóveda del palazzo Barberini representa la alegoría de la Divina Sabiduría. La Sabiduría está personificada por una mujer sentada en un trono rodeada por figuras alegóricas como la Divinidad, la Suavidad, la Eternidad y la Justicia. En la parte inferior se representa el globo terráqueo iluminado, simbolizando que la sabiduría terrenal nació en Egipto pero ahora Italia ha heredado su prestigio religioso y sapiental bajo el papado de U
Architectural And Structural Design Of Blast Resistant Buildings - REPORTPaul Jomy
The objective of this study is to shed light on blast resistant building theories, the enhancement of building security against the effect of explosives in both architectural and structural design process and the design techniques that should be carried out. Firstly, explosives and explosion type have been explained briefly. In addition, the general aspects of explosion process have been presented to clarify the effect of explosives on buildings. To have a better understanding of explosives and characteristics of explosions will enable us to make blast resistant building design much more efficiently. Essential techniques for increasing the capacity of a building to provide protection against explosive effects is discussed both with an architectural and structural approach.
Computation of blast loading for a multi storeyed framed buildingeSAT Journals
Abstract
The number and intensity of domestic and international terrorist activities have heightened our concerns towards the safety of our infrastructure systems. Due to different accidental or intentional events, related to important structures all over the world, explosive loads or blast loads have received considerable attention in recent years. The development in this field is made mostly through publication of the U.S. Army Corps of Engineers, Naval Facilities Engineering Command (NAVFAC), and Air Force Civil Engineer Support Agency. In India also, the guidelines for the blast loading are published in IS 4991. In the present study, blast pressures for different weights of surface blast or TNT and varying stand-off distances are computed for a multi-storeyed framed building adopting wave scaling laws given by U.S Army technical manual (UFC3-340-02). Blast pressures for different cases are computed using correlation between blast pressure and blast scaled distance based on charts given in U.S manual. Time history loading is also obtained with parameters of reflected total over pressure and duration of positive phase of blast.
Keywords: blast loading, blast wave, scaled distance, blast pressure.
A brief description on explosion,types of explosion,Physical explosion,details on chemical explosion,types,everything which is needed to understand chemical explosion properly is given here.Case study is also included.
This document discusses wind-induced motion in tall buildings. It begins by explaining the increasing trend of tall building construction globally due to population growth and land scarcity. Tall buildings experience significant lateral loads from wind that can cause dynamic motion, so accurate structural design methods are important. Wind forces on tall buildings are analyzed using wind tunnel tests on scaled models to determine pressures and loads. Vortex shedding is identified as a critical phenomenon that can cause across-wind vibrations if the shedding frequency matches the building's natural frequency. The document provides background on wind characteristics, types of winds, wind speed variation with height, and definitions of high-rise buildings.
FAMAT was founded in 1981 in Saint-Nazaire, France as a joint venture between General Electric and Snecma to manufacture high-tech engine frames and assemblies. It employs 393 people across 25,000 square meters of facilities. FAMAT produces major structural components for commercial aircraft engines made by GE and Snecma that power planes from Airbus, Boeing, and soon Comac.
HappyDev-lite-2016-весна 05 Андрей Юдин. Javascript - мультиинструмент для всехHappyDev-lite
Доклад для тех, кто только выбирает свой путь, ищет куда податься в программировании.
Расскажу о том, что такое JS и что с его помощью можно делать.
Расскажу о использовании JS в браузерах, о его применении на мобильных платформах. О том что с его помощью можно делать десктопные приложения и многое другое.
Spatial data infrastructure in KyrgyzstanUnison Group
The document discusses the limitations of Kyrgyzstan's spatial data infrastructure and the implications for climate adaptation efforts. It finds that there is currently no national SDI, and data exists in silos with poor coordination and data sharing between institutions. This poses challenges for climate adaptation projects that require spatial data on topics like boundaries, satellite imagery, and climate/weather. The document recommends establishing a working group to develop an NSDI through improved data access, standards, and awareness of SDI benefits. This could help adaptation efforts and unlock economic opportunities through increased transparency, efficiency and investment.
Este fresco de la bóveda del palazzo Barberini representa la alegoría de la Divina Sabiduría. La Sabiduría está personificada por una mujer sentada en un trono rodeada por figuras alegóricas como la Divinidad, la Suavidad, la Eternidad y la Justicia. En la parte inferior se representa el globo terráqueo iluminado, simbolizando que la sabiduría terrenal nació en Egipto pero ahora Italia ha heredado su prestigio religioso y sapiental bajo el papado de U
Architectural And Structural Design Of Blast Resistant Buildings - REPORTPaul Jomy
The objective of this study is to shed light on blast resistant building theories, the enhancement of building security against the effect of explosives in both architectural and structural design process and the design techniques that should be carried out. Firstly, explosives and explosion type have been explained briefly. In addition, the general aspects of explosion process have been presented to clarify the effect of explosives on buildings. To have a better understanding of explosives and characteristics of explosions will enable us to make blast resistant building design much more efficiently. Essential techniques for increasing the capacity of a building to provide protection against explosive effects is discussed both with an architectural and structural approach.
A Review on Blast Analysis of Reinforced Concrete Viaduct Pier StructuresIRJET Journal
The document discusses blast analysis of reinforced concrete viaduct pier structures. It begins with an introduction discussing the increasing population leading to more infrastructure development like bridges and viaducts using reinforced concrete piers. It then discusses how explosions can occur near these piers from accidents or terrorism, potentially causing structural failure and casualties. The document reviews explosion types, how blast loads are predicted and modeled, literature on analyzing reinforced concrete structures under blast loading, and methods to improve blast resistance of structures.
As we know that in today’s world terrorists’ attacks are common and not a single country is completely safe. High-explosive detonations propagate blast energy in all directions, causing extensive damage to both the target structure and nearby buildings. Structural damage and the glass exposure have been major contributors to death and injury for the targeted buildings. If the structures are properly designed for these abnormal loads damage can be controlled. Within the Indian Standard Codes these types of situations are not dealt with and they need further explanation as the engineers have no guidelines on how to design or evaluate structures for the blast phenomenon for which a detailed understanding of structural behavior as well as effects of different kinds of blast load is required. The calculation of blast load is studied in this report using various parameters.
IRJET- The State of the Art on Analytical Investigation of RCC Viaduct Pi...IRJET Journal
This document discusses analytical investigation of reinforced concrete viaduct pier structures due to air blast loads from explosions. It begins with an introduction to transportation infrastructure like bridges, flyovers and metros that use piers. It then discusses explosion phenomena like deflagration and detonation that generate blast waves. It covers blast loading characteristics like peak pressure, impulse, scaling laws and methods for calculating blast loads. The document aims to understand blast loads to inform the design of pier structures to withstand explosions and reduce casualties.
IRJET- A Review on “Analysis, design and study of behavior of RC Structur...IRJET Journal
This document reviews research on analyzing and designing reinforced concrete structures to withstand blast loads of various intensities. It discusses how blast loads generate pressure waves that can damage structures and cause loss of life. The study aims to understand blast wave parameters like overpressure for different explosive charge amounts and distances. It also looks at how blast loads affect structures differently based on factors like surface bursts versus air bursts. The goal is to minimize damage to structures and occupants from explosive events.
“Comparative Analysis of Blast Load on Multi Storey R.C.C. Building at Differ...IRJET Journal
This document summarizes a research paper that analyzes the effects of blast loads on multi-story reinforced concrete (RCC) buildings using computer modeling. 32 different blast load cases are modeled using ETABS software, varying the standoff distance (20m and 30m), TNT charge weight (50-300kg), and location of the blast (external walls and internal columns). The response of the building models under blast loading is examined through time history analysis, evaluating story displacement, drift, and shear. The goal is to better understand how RCC buildings respond structurally to blast loads at different locations and intensities.
This document discusses analyzing the response of a reinforced concrete building to blast loads. The building was modeled in Inventor and analyzed in Altair and Staad Pro. Transient structural analysis was used to simulate the effects of uniform blast pressure loads at different standoff distances. The objectives were to study deformation of the structure under positive and negative blast phases and compare effects of blast pressure at 5m and 6m standoffs. A 3-story commercial building was modeled and analyzed, with blast assumed from the front corner at 5m and 6m distances.
This document analyzes the response of different building models subjected to blast loads using ETABS software. A 12-story building is analyzed for 4 cases with different explosive charge weights (100kg and 200kg) and standoff distances (20m and 40m). Blast parameters are calculated using code standards. Four building models are then analyzed - a normal model, and models with increased member sizes, added shear walls, and added bracing. Storey displacement and drift are compared to determine the most blast resistant model.
Structures to Resist the Effects of the Accidental Explosionsijtsrd
Currently in the field of civil engineering the requirement regarding knowledge blast loads are essential. Every country in the world are having terrorist threats. As the scenario of terrorist attacks are unpredictable neither location nor blast material used. This provides an outline to analysis and design to resist blast loads. We have taken an example model to illustrate evaluation of blast parameters which are used in the analysis. The analysis and design of structures to resist blast explosive loads is having utmost importance compared to the conventional type of structures. Where Loading is actually independent of time variation. From past few decades terrorist attacks are becoming a new threat to people lives material used, its quantity, and distance from structure etc. Since we dont know when the blasting activity is going to be happened and type of charge material is used, depends on importance of structure we have to make sure the design of structure should be such that it should resist the failure against blasting activities and to property also. The amount of damage caused to structure is depends upon type of charge. Blast loads, its contribution to structures and other required provisions are opted from Technical Manual 5 1300 and IS 4991 1968.The design method used is Equivalent Static Approach. Analysis of frames of structure is done with software package. Kota Sudeep | V. Narasimha Rao ""Structures to Resist the Effects of the Accidental Explosions"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23455.pdf
Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/23455/structures-to-resist-the-effects-of-the-accidental-explosions/kota-sudeep
This document discusses the design of blast resistant structures. It begins by explaining that terrorist attacks involving explosives have increased the need to consider blast loads in building design. The objectives are to explain blast resistant design theories and techniques. It describes the effects of explosions, including shock waves and pressure decay over distance. Design considerations for blast resistant structures include reinforcing steel, concrete strength, and "bomb proof" concrete with steel fibers. The document also discusses reducing blast impacts through increasing stand-off distance from explosions. Both architectural and structural design aspects are important for blast resistance. Structural designs aim to prevent overall collapse and distribute explosion energy without failure.
This document discusses blast loading on structures from explosions. It provides an overview of how to determine blast load as a pressure-time history and analytically model the load in structural analysis software. It presents the key parameters for characterizing explosions, including TNT equivalency, scaled distance, peak overpressure, and duration. It also describes how the explosion wave interacts with structures and the ground, including pressure magnification. The document then demonstrates modeling a fictional structure subjected to blast loading in SAP2000 software to preliminarily assess the structure's response.
Dynamic failure of composite and sandwich structuresSpringer
This document discusses experiments conducted on sandwich composite materials and composite tubes subjected to air and underwater blast loading. Explosive charges ranging from 0.64-100 kg of TNT were used. High-speed photography and digital image correlation were used to monitor deformation during air blasts, while strain gauges monitored response during underwater blasts. Different failure mechanisms like core crushing, skin cracking, and delamination were observed depending on whether the blast was in air or underwater. The results provide data to develop analytical and computational models of blast loading on composite structures.
IRJET-The Study of Effect of Blast Load on Multi-Storey Building by using Tim...IRJET Journal
This document discusses a study on the effect of blast loads on multi-storey buildings using time history analysis. A G+4 storey reinforced concrete building is subjected to blast loads from charges weighing 100, 300, and 500kg placed at standoff distances of 30, 40, and 50m. Nonlinear time history analysis is carried out using ETABS 2016 software. The response of the structure is examined in terms of displacement, velocity, acceleration, storey drift, beam forces, column forces, and storey displacement. The results show that when the blast source is closer and the charge weight is higher, the building response is more critical.
Analysis of Blast Resistant RCC StructureIRJET Journal
This document presents a study on the effects of blast loading on a six-story reinforced concrete building. The blast load from an explosion of 100kg of TNT at a distance of 30m from the building is analytically determined as a pressure-time history. Key blast parameters such as peak overpressure, dynamic pressure, and positive impulse are calculated based on established formulas. The numerical model of the building is then created in SAP2000 software and analyzed to determine the influence of blast loading on the structure in terms of peak displacements, velocities, accelerations, and inter-story drift. The goal is to better understand how to strengthen structures to resist blast loads from explosions.
This document discusses the design of blast resistant structures. It covers types of blasts, principles of blast resistant design such as maintaining safe stand-off zones and minimizing debris, and guidelines for analysis including redundancy and ductile structure elements. It also describes procedures for analysis using pressure-impulse diagrams and finite element methods. Acceptable damage levels from minor to major are defined. The key differences between blast and seismic loads are outlined, and it is concluded that while withstanding any attack is impractical, performance can be improved through appropriate design processes.
Dynamic failure of composite and sandwich structuresSpringer
This document discusses research on the blast loading of sandwich composite materials and composite tubes. Air-blast and underwater-blast experiments were conducted using explosive charges ranging from 0.64-100 kg of TNT. High-speed photography and digital image correlation were used to monitor the deformation and failure mechanisms of glass fiber and carbon fiber sandwich panels under air-blast loading. Strain gauges were also used to monitor the response of similar sandwich materials and glass fiber tubes during underwater blast experiments. The experiments showed that underwater blast loading caused global core crushing in sandwich panels, while air-blast loading resulted in distributed core shear failure. The results provide data to develop analytical and computational models of blast loading and highlight the importance of boundary conditions in blast-
This document discusses assessing the risk of structural collapse from blast loading. It begins by introducing the problem of assessing building safety against terrorist bomb attacks. It then discusses calculating the annual risk of progressive structural collapse from blast loading through simulating possible blast scenarios and analyzing structural stability. As a case study, it calculates the blast fragility and annual risk of collapse for a four-story steel building. The document provides background on modeling blast loading and effects, including empirical formulas for predicting blast pressure over time. It emphasizes that accurately assessing blast risk requires considering uncertainties and probabilities of events through a performance-based probabilistic framework.
Comparative Study of Response of Structures Subjected To Blast and Earthquake...IJERA Editor
The increase in the number of terrorist attacks especially in the last few years has shown that the effect of blast
load on building is a serious challenge that should be taken in to consideration for designing of structures. This
type of loading damages the structures, externally as well as internally. Hence the blast load should be
considered with same importance as earthquake load. The present study includes the comparative performance
of G+3 storey building subjected to blast and earthquake loading using ETABS. For four storey building using
different input parameters like charge explosive, stand-off distance and layout of building the blast pressure are
conducted and linear time history analysis is carried out. Comparative study for blast and earthquake loading is
carried out for different parameters like maximum storey displacement, storey drift and quantity of materials.
Safe charge explosive and safe stand-off distance are obtained for the RCC structure with the sections of
structural elements same as per the requirement for earthquake resistance. Displacement is higher for the blast
loading as compared to earthquake loading and very high for the storey at which blast load is applied. Quantity
of concrete is 40 percentages higher for blast resistant building than the earthquake resistant building.
Analysis of blast loading effect on high rise buildingsAlexander Decker
This document analyzes the effect of blast loading on high-rise buildings. It describes modeling a 30-story reinforced concrete building in SAP2000 and subjecting it to blast loads from charges of 800 and 1600 pounds of TNT at distances of 5 and 10 meters. The results show that as the standoff distance increases, inter-story drift decreases, and as the explosive weight increases, inter-story drift increases. The maximum inter-story drift of 16.5 mm occurred for an irregular frame model with a charge weight of 1600 pounds at a distance of 5 meters.
Analysis of blast loading effect on high rise buildingsAlexander Decker
This document analyzes the effects of blast loading on high-rise buildings. It describes modeling a 30-story reinforced concrete building in SAP2000 and subjecting it to blast loads from charges of 800 and 1600 pounds of TNT at distances of 5 and 10 meters. The results show maximum inter-story drift occurs on the first story due to its proximity to the blast. Regular infill frames performed best by exhibiting the lowest drift values, while irregular frames performed worst. Increasing standoff distance and decreasing charge weight both reduced structural response based on inter-story drift values.
Study of Behaviour of Strip Foundation On Various Soils in Slopes2.pptxMansi Kakani
This document presents an introduction to a project on assessing and optimizing the water distribution system in Nashik, India using EPANET software. The objectives are to analyze the existing system using EPANET, suggest improvements if needed to meet demand, optimize pipe sizes and locations of components like pipes, tanks and pumps, and design the system to be more economical while meeting peak demand. The methodology describes using EPANET to model the system, edit properties, operate the system in the software, view results, and optimize the design. Literature on previous studies using EPANET to model water systems is also reviewed.
This document presents a project presentation on "Manufacturing of Paver Blocks using Construction and Demolition Wastes". The presentation discusses using construction and demolition waste to manufacture paver blocks in order to minimize waste and reduce environmental impacts. It provides an introduction to the topic, objectives of the project which include reuse of waste and increasing block strength. A literature review is presented summarizing several papers on using various wastes like glass powder, marble dust and steel aggregates in paver block production. The methodology explains the process of material collection, mix design, block casting and testing of blocks made with cement and C&D steel waste.
A Review on Blast Analysis of Reinforced Concrete Viaduct Pier StructuresIRJET Journal
The document discusses blast analysis of reinforced concrete viaduct pier structures. It begins with an introduction discussing the increasing population leading to more infrastructure development like bridges and viaducts using reinforced concrete piers. It then discusses how explosions can occur near these piers from accidents or terrorism, potentially causing structural failure and casualties. The document reviews explosion types, how blast loads are predicted and modeled, literature on analyzing reinforced concrete structures under blast loading, and methods to improve blast resistance of structures.
As we know that in today’s world terrorists’ attacks are common and not a single country is completely safe. High-explosive detonations propagate blast energy in all directions, causing extensive damage to both the target structure and nearby buildings. Structural damage and the glass exposure have been major contributors to death and injury for the targeted buildings. If the structures are properly designed for these abnormal loads damage can be controlled. Within the Indian Standard Codes these types of situations are not dealt with and they need further explanation as the engineers have no guidelines on how to design or evaluate structures for the blast phenomenon for which a detailed understanding of structural behavior as well as effects of different kinds of blast load is required. The calculation of blast load is studied in this report using various parameters.
IRJET- The State of the Art on Analytical Investigation of RCC Viaduct Pi...IRJET Journal
This document discusses analytical investigation of reinforced concrete viaduct pier structures due to air blast loads from explosions. It begins with an introduction to transportation infrastructure like bridges, flyovers and metros that use piers. It then discusses explosion phenomena like deflagration and detonation that generate blast waves. It covers blast loading characteristics like peak pressure, impulse, scaling laws and methods for calculating blast loads. The document aims to understand blast loads to inform the design of pier structures to withstand explosions and reduce casualties.
IRJET- A Review on “Analysis, design and study of behavior of RC Structur...IRJET Journal
This document reviews research on analyzing and designing reinforced concrete structures to withstand blast loads of various intensities. It discusses how blast loads generate pressure waves that can damage structures and cause loss of life. The study aims to understand blast wave parameters like overpressure for different explosive charge amounts and distances. It also looks at how blast loads affect structures differently based on factors like surface bursts versus air bursts. The goal is to minimize damage to structures and occupants from explosive events.
“Comparative Analysis of Blast Load on Multi Storey R.C.C. Building at Differ...IRJET Journal
This document summarizes a research paper that analyzes the effects of blast loads on multi-story reinforced concrete (RCC) buildings using computer modeling. 32 different blast load cases are modeled using ETABS software, varying the standoff distance (20m and 30m), TNT charge weight (50-300kg), and location of the blast (external walls and internal columns). The response of the building models under blast loading is examined through time history analysis, evaluating story displacement, drift, and shear. The goal is to better understand how RCC buildings respond structurally to blast loads at different locations and intensities.
This document discusses analyzing the response of a reinforced concrete building to blast loads. The building was modeled in Inventor and analyzed in Altair and Staad Pro. Transient structural analysis was used to simulate the effects of uniform blast pressure loads at different standoff distances. The objectives were to study deformation of the structure under positive and negative blast phases and compare effects of blast pressure at 5m and 6m standoffs. A 3-story commercial building was modeled and analyzed, with blast assumed from the front corner at 5m and 6m distances.
This document analyzes the response of different building models subjected to blast loads using ETABS software. A 12-story building is analyzed for 4 cases with different explosive charge weights (100kg and 200kg) and standoff distances (20m and 40m). Blast parameters are calculated using code standards. Four building models are then analyzed - a normal model, and models with increased member sizes, added shear walls, and added bracing. Storey displacement and drift are compared to determine the most blast resistant model.
Structures to Resist the Effects of the Accidental Explosionsijtsrd
Currently in the field of civil engineering the requirement regarding knowledge blast loads are essential. Every country in the world are having terrorist threats. As the scenario of terrorist attacks are unpredictable neither location nor blast material used. This provides an outline to analysis and design to resist blast loads. We have taken an example model to illustrate evaluation of blast parameters which are used in the analysis. The analysis and design of structures to resist blast explosive loads is having utmost importance compared to the conventional type of structures. Where Loading is actually independent of time variation. From past few decades terrorist attacks are becoming a new threat to people lives material used, its quantity, and distance from structure etc. Since we dont know when the blasting activity is going to be happened and type of charge material is used, depends on importance of structure we have to make sure the design of structure should be such that it should resist the failure against blasting activities and to property also. The amount of damage caused to structure is depends upon type of charge. Blast loads, its contribution to structures and other required provisions are opted from Technical Manual 5 1300 and IS 4991 1968.The design method used is Equivalent Static Approach. Analysis of frames of structure is done with software package. Kota Sudeep | V. Narasimha Rao ""Structures to Resist the Effects of the Accidental Explosions"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23455.pdf
Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/23455/structures-to-resist-the-effects-of-the-accidental-explosions/kota-sudeep
This document discusses the design of blast resistant structures. It begins by explaining that terrorist attacks involving explosives have increased the need to consider blast loads in building design. The objectives are to explain blast resistant design theories and techniques. It describes the effects of explosions, including shock waves and pressure decay over distance. Design considerations for blast resistant structures include reinforcing steel, concrete strength, and "bomb proof" concrete with steel fibers. The document also discusses reducing blast impacts through increasing stand-off distance from explosions. Both architectural and structural design aspects are important for blast resistance. Structural designs aim to prevent overall collapse and distribute explosion energy without failure.
This document discusses blast loading on structures from explosions. It provides an overview of how to determine blast load as a pressure-time history and analytically model the load in structural analysis software. It presents the key parameters for characterizing explosions, including TNT equivalency, scaled distance, peak overpressure, and duration. It also describes how the explosion wave interacts with structures and the ground, including pressure magnification. The document then demonstrates modeling a fictional structure subjected to blast loading in SAP2000 software to preliminarily assess the structure's response.
Dynamic failure of composite and sandwich structuresSpringer
This document discusses experiments conducted on sandwich composite materials and composite tubes subjected to air and underwater blast loading. Explosive charges ranging from 0.64-100 kg of TNT were used. High-speed photography and digital image correlation were used to monitor deformation during air blasts, while strain gauges monitored response during underwater blasts. Different failure mechanisms like core crushing, skin cracking, and delamination were observed depending on whether the blast was in air or underwater. The results provide data to develop analytical and computational models of blast loading on composite structures.
IRJET-The Study of Effect of Blast Load on Multi-Storey Building by using Tim...IRJET Journal
This document discusses a study on the effect of blast loads on multi-storey buildings using time history analysis. A G+4 storey reinforced concrete building is subjected to blast loads from charges weighing 100, 300, and 500kg placed at standoff distances of 30, 40, and 50m. Nonlinear time history analysis is carried out using ETABS 2016 software. The response of the structure is examined in terms of displacement, velocity, acceleration, storey drift, beam forces, column forces, and storey displacement. The results show that when the blast source is closer and the charge weight is higher, the building response is more critical.
Analysis of Blast Resistant RCC StructureIRJET Journal
This document presents a study on the effects of blast loading on a six-story reinforced concrete building. The blast load from an explosion of 100kg of TNT at a distance of 30m from the building is analytically determined as a pressure-time history. Key blast parameters such as peak overpressure, dynamic pressure, and positive impulse are calculated based on established formulas. The numerical model of the building is then created in SAP2000 software and analyzed to determine the influence of blast loading on the structure in terms of peak displacements, velocities, accelerations, and inter-story drift. The goal is to better understand how to strengthen structures to resist blast loads from explosions.
This document discusses the design of blast resistant structures. It covers types of blasts, principles of blast resistant design such as maintaining safe stand-off zones and minimizing debris, and guidelines for analysis including redundancy and ductile structure elements. It also describes procedures for analysis using pressure-impulse diagrams and finite element methods. Acceptable damage levels from minor to major are defined. The key differences between blast and seismic loads are outlined, and it is concluded that while withstanding any attack is impractical, performance can be improved through appropriate design processes.
Dynamic failure of composite and sandwich structuresSpringer
This document discusses research on the blast loading of sandwich composite materials and composite tubes. Air-blast and underwater-blast experiments were conducted using explosive charges ranging from 0.64-100 kg of TNT. High-speed photography and digital image correlation were used to monitor the deformation and failure mechanisms of glass fiber and carbon fiber sandwich panels under air-blast loading. Strain gauges were also used to monitor the response of similar sandwich materials and glass fiber tubes during underwater blast experiments. The experiments showed that underwater blast loading caused global core crushing in sandwich panels, while air-blast loading resulted in distributed core shear failure. The results provide data to develop analytical and computational models of blast loading and highlight the importance of boundary conditions in blast-
This document discusses assessing the risk of structural collapse from blast loading. It begins by introducing the problem of assessing building safety against terrorist bomb attacks. It then discusses calculating the annual risk of progressive structural collapse from blast loading through simulating possible blast scenarios and analyzing structural stability. As a case study, it calculates the blast fragility and annual risk of collapse for a four-story steel building. The document provides background on modeling blast loading and effects, including empirical formulas for predicting blast pressure over time. It emphasizes that accurately assessing blast risk requires considering uncertainties and probabilities of events through a performance-based probabilistic framework.
Comparative Study of Response of Structures Subjected To Blast and Earthquake...IJERA Editor
The increase in the number of terrorist attacks especially in the last few years has shown that the effect of blast
load on building is a serious challenge that should be taken in to consideration for designing of structures. This
type of loading damages the structures, externally as well as internally. Hence the blast load should be
considered with same importance as earthquake load. The present study includes the comparative performance
of G+3 storey building subjected to blast and earthquake loading using ETABS. For four storey building using
different input parameters like charge explosive, stand-off distance and layout of building the blast pressure are
conducted and linear time history analysis is carried out. Comparative study for blast and earthquake loading is
carried out for different parameters like maximum storey displacement, storey drift and quantity of materials.
Safe charge explosive and safe stand-off distance are obtained for the RCC structure with the sections of
structural elements same as per the requirement for earthquake resistance. Displacement is higher for the blast
loading as compared to earthquake loading and very high for the storey at which blast load is applied. Quantity
of concrete is 40 percentages higher for blast resistant building than the earthquake resistant building.
Analysis of blast loading effect on high rise buildingsAlexander Decker
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1. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
ARCHITECTURAL AND STRUCTURAL DESIGN FOR
BLAST RESISTANT BUILDINGS
Zeynep Koccaz1
Fatih Sutcu2
Necdet Torunbalci3
1 MSc Student, Institute of Science, Technical University, Taskisla, Istanbul, Turkey
2 Research Associate PhD, Faculty of Architecture, Istanbul Technical University, Taskisla, Istanbul, Turkey
E-mail address: fatihsutcu@hotmail.com
3Associate Professor, Faculty of Architecture, Istanbul Technical University, Taskisla, Istanbul, Turkey
ABSTRACT
The increase in the number of terrorist attacks especially in the last few years has shown that the effect of blast
loads on buildings is a serious matter that should be taken into consideration in the design process. Although these
kinds of attacks are exceptional cases, man-made disasters; blast loads are in fact dynamic loads that need to be
carefully calculated just like earthquake and wind loads.
The objective of this study is to shed light on blast resistant building design theories, the enhancement of building
security against the effects of explosives in both architectural and structural design process and the design
techniques that should be carried out. Firstly, explosives and explosion types have been explained briefly. In
addition, the general aspects of explosion process have been presented to clarify the effects of explosives on
buildings. To have a better understanding of explosives and characteristics of explosions will enable us to make
blast resistant building design much more efficiently. Essential techniques for increasing the capacity of a building
to provide protection against explosive effects is discussed both with an architectural and structural approach.
KEYWORDS: Blast resistant design, blast waves, explosive effects
1 INTRODUCTION
Damage to the assets, loss of life and social panic are factors that have to be minimized if the threat of terrorist
action cannot be stopped. Designing the structures to be fully blast resistant is not an realistic and economical
option, however current engineering and architectural knowledge can enhance the new and existing buildings to
mitigate the effects of an explosion.
The main target of this study is to provide guidance to engineers and architects where there is a necessity of
protection against the explosions caused by detonation of high explosives. The guidance describes measures for
mitigating the effects of explosions, therefore providing protection for human, structure and the valuable equipment
inside. The paper includes information about explosives, blast loading parameters and enhancements for blast
resistant building design both with an architectural and structural approach. Only explosions caused by high
explosives (chemical reactions) are considered within the study. High explosives are solid in form and are
commonly termed condensed explosives. TNT (trinitrotoluene) is the most widely known example. There are 3
kinds of explosions which are unconfined explosions, confined explosions and explosions caused by explosives
attached to the structure. [2]
Unconfined explosions can occur as an air-burst or a surface burst. In an air burst explosion, the detonation of the
high explosive occurs above the ground level and intermediate amplification of the wave caused by ground
reflections occurs prior to the arrival of the initial blast wave at a building (Figure 1) As the shock wave continues
2. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
to propagate outwards along the ground surface, a front commonly called a Mach stem is formed by the interaction
of the initial wave and the reflected wave.
However a surface burst explosion occurs when the detonation occurs close to or on the ground surface. The initial
shock wave is reflected and amplified by the ground surface to produce a reflected wave. (Figure 2) Unlike the air
burst, the reflected wave merges with the incident wave at the point of detonation and forms a single wave. In the
majority of cases, terrorist activity occurres in built-up areas of cities, where devices are placed on or very near the
ground surface.
Figure 1. Air burst with ground reflections Figure 2. Surface burst
When an explosion occurs within a building, the pressures associated with the initial shock front will be high and
therefore will be amplified by their reflections within the building. This type of explosion is called a confined
explosion. In addition and depending on the degree of confinement, the effects of the high temperatures and
accumulation of gaseous products produced by the chemical reaction involved in the explosion will cause additional
pressures and increase the load duration within the structure. Depending on the extent of venting, various types of
confined explosions are possible. (Figure 3)
Fully vented partially vented fully confined
Figure 3. Fully vented, partially vented and fully confined explosions [2]
If detonating explosive is in contact with a structural component, e.g. a column, the arrival of the detonation wave at
the surface of the explosive will generate intense stress waves in the material and resulting crushing of the material.
Except that an explosive in contact with a structure produces similar effects to those of unconfined or confined
explosions.
There are many forms of high explosive available and as each explosive has its own detonation characteristics, the
properties of each blast wave will be different. TNT is being used as the standard benchmark, where all explosions
can be expressed in terms of an equivalent charge mass of TNT. The most common method of equalization is based
on the ratio of an explosive’s specific energy to that of TNT.
3. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
2 EXPLOSION PROCESS FOR HIGH EXPLOSIVES
An explosion occurs when a gas, liquid or solid material goes through a rapid chemical reaction. When the
explosion occurs, gas products of the reaction are formed at a very high temperature and pressure at the source.
These high pressure gasses expand rapidly into the surrounding area and a blast wave is formed. Because the gases
are moving, they cause the surrounding air move as well. The damage caused by explosions is produced by the
passage of compressed air in the blast wave. Blast waves propagate at supersonic speeds and reflected as they meet
objects. As the blast wave continues to expand away from the source of the explosion its intensity diminishes and its
effect on the objects is also reduced. However, within tunnels or enclosed passages, the blast wave will travel with
very little diminution.
Close to the source of explosion the blast wave is formed and violently hot and expanding gases will exert intense
loads which are difficult to quantify precisely. Once the blast wave has formed and propagating away from the
source, it is convenient to separate out the different types of loading experienced by the surrounding objects.[3]
Three effects have been identified in three categories. The effect rapidly compressing the surrounding air is called
“air shock wave”. The air pressure and air movement effect due to the accumulation of gases from the explosion
chemical reactions is called “dynamic pressure” and the effect rapidly compressing the ground is called “ground
shock wave”.
The air shock wave produces an instantaneous increase in pressure above the ambient atmospheric pressure at a
point some distance from the source. This is commonly referred to as overpressure. As a consequence, a pressure
differential is generated between the combustion gases and the atmosphere, causing a reversal in the direction of
flow, back towards the center of the explosion, known as a negative pressure phase. This is a negative pressure
relative to atmospheric, rather than absolute negative pressure. (Figure 4) Equilibrium is reached when the air is
returned to its original state.
Figure 4. Blast wave pressures plotted against time
As a rough approximation, 1kg of explosive produces about 1m3
of gas. As this gas expands, its act on the air
surrounding the source of the explosion causes it to move and increase in pressure. The movement of the displaced
air may affect nearby objects and cause damage. Except for a confinement case, the effects of the dynamic pressure
diminish rapidly with distance from source.
The ground shock leaving the site of an explosion consists of three principal components [3]. A compression wave
which travels radially from the source; a shear wave which travels radially and comprises particle movements in a
plane normal to the radial direction where the ground shock wave intersects with the surface and a surface or
Raleigh wave. These waves propagate at different velocities and alternate at different frequencies.
4. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
3 ARCHITECTURAL ASPECT OF BLAST RESISTANT BUILDING DESIGN
The target of blast resistant building design philosophy is minimizing the consequences to the structure and its
inhabitants in the event of an explosion. A primary requirement is the prevention of catastrophic failure of the entire
structure or large portions of it. It is also necessary to minimize the effects of blast waves transmitted into the
building through openings and to minimize the effects of projectiles on the inhabitants of a building. However, in
some cases blast resistant building design methods, conflicts with aesthetical concerns, accessibility variations, fire
fighting regulations and the construction budget restrictions.
3.1 Planning and layout
Much can be done at the planning stage of a new building to reduce potential threats and the associated risks of
injury and damage. The risk of a terrorist attack, necessity of blast protection for structural and non-structural
members, adequate placing of shelter areas within a building should be considered for instance. In relation to an
external threat, the priority should be to create as much stand-off distance between an external bomb and the
building as possible. On congested city centers there may be little or no scope for repositioning the building, but
what small stand-off there is should be secured where possible. This can be achieved by strategic location of
obstructions such as bollards, trees and street furniture. Figure 5 shows a possible external layout for blast safe
planning.
Figure 5. Schematic layout of site for protection against bombs [8]
3.2 Structural form and internal layout
Structural form is a parameter that greatly affects the blast loads on the building. Arches and domes are the types of
structural forms that reduce the blast effects on the building compared with a cubicle form. The plan-shape of a
building also has a significant influence on the magnitude of the blast load it is likely to experience. Complex
shapes that cause multiple reflections of the blast wave should be discouraged. Projecting roofs or floors, and
buildings that are U-shaped on plan are undesirable for this reason. It should be noted that single story buildings are
more blast resistant compared with multi-story buildings if applicable.
5. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
Partially or fully embed buildings are quite blast resistant. These kinds of structures take the advantage of the shock
absorbing property of the soil covered by. The soil provides protection in case of a nuclear explosion as well.
The internal layout of the building is another parameter that should be undertaken with the aim of isolating the
value from the threat and should be arranged so that the highest exterior threat is separated by the greatest distance
from the highest value asset. Foyer areas should be protected with reinforced concrete walls; double-dooring should
be used and the doors should be arranged eccentrically within a corridor to prevent the blast pressure entering the
internals of the building. Entrance to the building should be controlled and be separated from other parts of the
building by robust construction for greater physical protection. An underpass beneath or car parking below or
within the building should be avoided unless access to it can be effectively controlled.
Figure 6. Internal planning of a building
A possible fire that occurs within a structure after an explosion may increase the damage catasthrophically.
Therefore the internal members of the building should be designed to resist the fire.
3.3 Bomb shelter areas
The bomb shelter areas are specially designated within the building where vulnerability from the effects of the
explosion is at a minimum and where personnel can retire in the event of a bomb threat warning. These areas must
afford reasonable protection against explosions; ideally be large enough to accommodate the personnel involved
and be located so as to facilitate continual access. For modern-framed buildings, shelter areas should be located
away from windows, external doors, external walls and the top floors if the roof is weak. Areas surrounded by full-
height concrete walls should be selected and underground car parks, gas storage tanks, areas light weight partition
walls, e.g. internal corridors, toilet areas, or conference should be avoided while locating the shelter areas.
Basements can sometimes be useful shelter areas, but it is important to ensure that the building does not collapse on
top of them.
The functional aspects of a bomb shelter area should accommodate all the occupants of the building; provide
adequate communication with outside; provide sufficient ventilation and sanitation; limit the blast pressure to less
than the ear drum rupture pressure and provide alternative means of escape.
3.4 Installations
Gas, water, steam installations, electrical connections, elevators and water storage systems should be planned to
resist any explosion affects. Installation connections are critical points to be considered and should be avoided to
use in high-risk deformation areas. Areas with high damage receiving potential e.g. external walls, ceilings, roof
6. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
slabs, car parking spaces and lobbies also should be avoided to locate the electrical and other installations. The main
control units and installation feeding points should be protected from direct attacks. A reserve installation system
should be provided for a potential explosion and should be located remote from the main installation system.
3.5 Glazing and cladding
Glass from broken and shattered windows could be responsible for a large number of injuries caused by an
explosion in a city centre. The choice of a safer glazing material is critical and it has been found out that laminated
glass is the most effective in this context. On the other hand, applying transparent polyester anti-shatter film to the
inner surface of the glazing is as well an effective method.
For the cladding, several aspects of design should be considered to minimize the vulnerability of people within the
building and damage to the building itself. The amount of glazing in the facade should be minimized. This will limit
the amount of internal damage from the glazing and the amount of blast that can enter. It should also be ensured that
the cladding is fixed to the structure securely with easily accessible fixings. This will allow rapid inspection after an
explosion so that any failure or movement can be detected.
4 STRUCTURAL ASPECT OF BLAST RESISTANT BUILDING DESIGN
The front face of a building experiences peak overpressures due to reflection of an external blast wave. Once the
initial blast wave has passed the reflected surface of the building, the peak overpressure decays to zero. As the sides
and the top faces of the building are exposed to overpressures (which has no reflections and are lower than the
reflected overpressures on the front face), a relieving effect of blast overpressure is experienced on the front face.
The rear of the structure experiences no pressure until the blast wave has traveled the length of the structure and a
compression wave has begun to move towards the centre of the rear face. Therefore the pressure built up is not
instantaneous. On the other hand, there will be a time lag in the development of pressures and loads on the front and
back faces. This time lag causes translational forces to act on the building in the direction of the blast wave. [4]
Figure 7. Sequence of air-blast effects [5]
Blast loadings are extra ordinary load cases however, during structural design, this effect should be taken into
account with other loads by an adequate ratio. Similar to the static loaded case design, blast resistant dynamic
design also uses the limit state design techniques which are collapse limit design and functionality limit design. In
collapse limit design the target is to provide enough ductility to the building so that the explosion energy is
distributed to the structure without overall collapse. For collapse limit design the behavior of structural member
connections is crucial. In the case of an explosion, significant translational movement and moment occur and the
loads involved should be transferred from the beams to columns. The structure doesn’t collapse after the explosion
however it cannot function anymore.
Functionality limit design however, requires the building to continue functionality after a possible explosion
occurred. Only non-structural members like windows or cladding may need maintenance after an explosion so that
they should be designed ductile enough.
7. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
When the positive phase of the shock wave is shorter than the natural vibration period of the structure, the explosion
effect vanishes before the structure responds. This kind of blast loading is defined as “impulsive loading”. If the
positive phase is longer than the natural vibration period of the structure, the load can be assumed constant when the
structure has maximum deformation. This maximum deformation is a function of the blast loading and the structural
rigidity. This kind of blast loading is defined as “quasi-static loading”. Finally, if the positive phase duration is
similar to the natural vibration period of the structure, the behavior of the structure becomes quite complicated. This
case can be defined as “dynamic loading”.
Frame buildings designed to resist gravity, wind loads and earthquake loads in the normal way have frequently been
found to be deficient in two respects. When subjected to blast loading; the failure of beam-to-column connections
and the inability of the structure to tolerate load reversal. Beam-to-column connections can be subjected to very
high forces as the result of an explosion. These forces will have a horizontal component arising from the walls of
the building and a vertical component from the differential loading on the upper and lower surfaces of floors.
Providing additional robustness to these connections can be a significant enhancement.
In the connections, normal details for static loading have been found to be inadequate for blast loading. Especially
for the steelwork beam-to-column connections, it is essential for the connection to bear inelastic deformations so
that the moment frames could still operate after an instantaneous explosion. Figure 8 shows the side-plate
connection detail in question [7]. The main features to note in the reinforced concrete connection are the use of
extra links and the location of the starter bars in the connection [3] (Figure 8). These enhancements are intended to
reduce the risk of collapse or the connection be damaged, possibly as a result of a load reversal on the beam.
Figure 8. Enhanced beam-to-column connection details for steelwork [7] and reinforced concrete [3]
It is vital that in critical areas, full moment-resisting connections are made in order to ensure the load carrying
capacity of structural members after an explosion. Beams acting primarily in bending may also carry significant
axial load caused by the blast loading.
On the contrary, columns are predominantly loaded with axial forces under normal loading conditions, however
under blast loading they may be subjected to bending. Such forces can lead to loss of load-carrying capacity of a
section. In the case of an explosion, columns of a reinforced concrete structure are the most important members that
should be protected. Two types of wrapping can be applied to provide this. Wrapping with steel belts or wrapping
with carbon fiber-reinforced polymers (CFRP).
8. The 14
th
World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China
Cast-insitu reinforced concrete floor slabs are the preferred option for blast resistant buildings, but it may be
necessary to consider the use of precast floors in some circumstances. Precast floor units are not recommended for
use at first floor where the risk from an internal explosion is greatest. Lightweight roofs and more particularly, glass
roofs should be avoided and a reinforced concrete or precast concrete slab is to be preferred.
5 RESULTS
The aim in blast resistant building design is to prevent the overall collapse of the building and fatal damages.
Despite the fact that, the magnitude of the explosion and the loads caused by it cannot be anticipated perfectly, the
most possible scenarios will let to find the necessary engineering and architectural solutions for it.
In the design process it is vital to determine the potential danger and the extent of this danger. Most importantly
human safety should be provided. Moreover, to achieve functional continuity after an explosion, architectural and
structural factors should be taken into account in the design process, and an optimum building plan should be put
together.
This study is motivated from making buildings in a blast resistant way, pioneering to put the necessary regulations
into practice for preventing human and structural loss due to the blast and other human-sourced hazards and
creating a common sense about the explosions that they are possible threats in daily life. In this context,
architectural and structural design of buildings should be specially considered.
During the architectural design, the behavior under extreme compression loading of the structural form, structural
elements e.g. walls, flooring and secondary structural elements like cladding and glazing should be considered
carefully. In conventional design, all structural elements are designed to resist the structural loads. But it should be
remembered that, blast loads are unpredictable, instantaneous and extreme. Therefore, it is obvious that a building
will receive less damage with a selected safety level and a blast resistant architectural design. On the other hand,
these kinds of buildings will less attract the terrorist attacks.
Structural design after an environmental and architectural blast resistant design, as well stands for a great
importance to prevent the overall collapse of a building. With correct selection of the structural system, well
designed beam-column connections, structural elements designed adequately, moment frames that transfer
sufficient load and high quality material; it’s possible to build a blast resistant building. Every single member
should be designed to bear the possible blast loading. For the existing structures, retrofitting of the structural
elements might be essential. Although these precautions will increase the cost of construction, to protect special
buildings with terrorist attack risk like embassies, federal buildings or trade centers is unquestionable.
REFERENCES
[1] Koccaz Z. (2004) Blast Resistant Building Design, MSc Thesis, Istanbul Technical University, Istanbul, Turkey.
[2] Yandzio E., Gough M. (1999). Protection of Buildings Against Explosions, SCI Publication, Berkshire, U.K.
[3] Hill J.A., Courtney M.A. (1995). The structural Engineer’s Response to Explosion Damage. The Institution of
Structural Engineer’s Report, SETO Ltd, London.
[4] Mays G.C., Smith P.D. (1995). Blast Effects on Buildings, Thomas Telford Publications, Heron Quay, London.
[5] Hinman E. (2008) Blast Safety of the Building Envelope, WBDG, US
[6] Remennikov A. (2003) Essay 1: The HSBC Bank Building Bombing: Analysis of Blast Loading,
www.safeguardingaustralia.org.au/Essays/Essay3.html, Australia.
[7] Punch S. (1999) Blast Design of Steel Structures to Prevent Progressive Collapse, Structural Engineers
Association Convention Proceedings, Santa Barbara, California, U.S.A.
[8] Smith P.D., Hetherington J.G. (1994) Blast and ballistic loading of structures. Butterworth Heinemann.