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Article
Publication date: 15 July 2021

Vishal M. and Satyanarayanan K.S.

This paper delineates a literature review on fire-induced progressive collapse on structures and the effect of high temperature on structures and elements. After the…

Abstract

Purpose

This paper delineates a literature review on fire-induced progressive collapse on structures and the effect of high temperature on structures and elements. After the occurrences of fire in the World Trade Center in the USA, the researchers started concentrating on the progressive collapse that happens due to high temperature. Currently, most of the researchers are working on fire-induced progressive collapse on structures using high-temperature behavior on materials which are used for construction. The researchers have been doing an intensive study to find a better strategy to prevent the building from structural fire damage or collapse with available codes and guidelines throughout the world. This paper aims to provide a better understanding and analytical solutions on the basis of the recent works done by researchers in fire-induced progressive collapse and methods adopted to find the collapse mechanism.

Design/methodology/approach

This paper is written by studying different literature papers of 109 related to progressive collapse on structures and fire-induced progressive collapse.

Findings

The behavior of structures due to high temperature and collapse conditions due to fire in different scenarios is identified.

Originality/value

This paper fulfills an identified need to study how the structure can withstand high-temperature conditions in our day-to-day lives.

Details

Journal of Structural Fire Engineering, vol. 12 no. 3
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 1 July 2021

Silambarasan R., Veerappan A.R. and Shanmugam S.

The purpose of this study is to investigate the effect of structural deformations and bend angle on plastic collapse load of pipe bends under an in-plane closing bending…

Abstract

Purpose

The purpose of this study is to investigate the effect of structural deformations and bend angle on plastic collapse load of pipe bends under an in-plane closing bending moment (IPCM). A large strain formulation of three-dimensional non-linear finite element analysis was performed using an elastic perfectly plastic material. A unified mathematical solution was proposed to estimate the collapse load of pipe bends subjected to IPCM for the considered range of bend characteristics.

Design/methodology/approach

ABAQUS was used to create one half of the pipe bend model due to its symmetry on the longitudinal axis. Structural deformations, i.e. ovality (Co) and thinning (Ct) varied from 0% to 20% in 5% steps while the bend angle (ø) varied from 30° to 180° in steps of 30°.

Findings

The plastic collapse load decreases as the bend angle increase for all pipe bend models. A remarkable effect on the collapse load was observed for bend angles between 30° and 120° beyond which a decline was noticed. Ovality had a significant effect on the collapse load with this effect decreasing as the bend angle increased. The combined effect of thinning and bend angle was minimal for the considered models and the maximum per cent variation in collapse load was 5.76% for small bend angles and bend radius pipe bends and less than 2% for other cases.

Originality/value

The effect of structural deformations and bend angle on collapse load of pipe bends exposed to IPCM has been not studied in the existing literature.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 29 April 2021

Joseph Kwaku Kidido, Ibrahim Yahaya Wuni and Edward Ansah

The study investigated the perceived causes of structural failure of public buildings, frequency of stability checks, stability checking procedures, measures to enhance…

Abstract

Purpose

The study investigated the perceived causes of structural failure of public buildings, frequency of stability checks, stability checking procedures, measures to enhance public building stability checks and the roles of facility managers in the Accra Metropolis of Ghana.

Design/methodology/approach

Following a comprehensive literature review, the study employed a structured questionnaire survey and gathered the opinions of sixty-seven facility managers on the facility management practices. Following statistical pretesting of the dataset for reliability, distribution and agreement among the responses, the study analysed the dataset using mean scoring and weighted analysis.

Findings

The analysis showed that external building inspectors rarely inspect stability checks of the studied public buildings in Accra. It is also found that both reactive and proactive stability checking protocols are implemented in public buildings in Accra, but inadequate knowledge of facility managers limits technical stability checks. The study further revealed that stability checks of public buildings can be enhanced through incorporating site and location conditions into the design early upfront, active engagement of facility managers in the design and construction of public buildings, adequate budgetary provisioning for planned maintenance of public buildings, and encouraging appropriate use of public buildings.

Originality/value

This paper, to the best of the authors' knowledge, represents the first attempt to comprehensively examine the causes of structural failure of public buildings, frequency of stability checks, stability checking procedures, measures to enhance public building stability checks and the roles of facility managers in Ghana, from the perspective facility management.

Details

Property Management, vol. 39 no. 4
Type: Research Article
ISSN: 0263-7472

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Book part
Publication date: 14 July 2006

David Ray Griffin

I argue that the official story about the collapses of the Twin Towers and building 7 of the World Trade Center, according to which the collapses were caused by fire …

Abstract

I argue that the official story about the collapses of the Twin Towers and building 7 of the World Trade Center, according to which the collapses were caused by fire – combined, in the case of the Twin Towers, with the effects of the airplane impacts – cannot be true, for two major reasons. One reason is that fire has never, except allegedly three times on 9/11, caused the total collapse of steel-frame high-rise buildings. All (other) such collapses have been produced by the use of explosives in the procedure known as “controlled demolition.” The other major problem is that the collapses of all three buildings had at least 11 features that would be expected if, and only if, explosives had been used.

I also show the importance of the recently released of 9/11 Oral Histories recorded by the New York Fire Department. With regard to the Twin Towers, many of the firefighters and medical workers said they observed multiple explosions and other phenomena indicative of controlled demolition. With regard to building 7, many testimonies point to widespread foreknowledge that the building was going to collapse, and some of the testimonies contradict the official story that this anticipation of the building's collapse was based on objective indications. These testimonies further strengthen the already virtually conclusive case that all three buildings were brought down by explosives.

I conclude by calling on the New York Times, which got the 9/11 Oral Histories released, now to complete the task of revealing the truth about 9/11.

Details

The Hidden History of 9-11-2001
Type: Book
ISBN: 978-1-84950-408-9

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Article
Publication date: 2 March 2020

Mohammed Y. Fattah and Basma A. Dawood

This study aims to predict the volume changes and collapse potential (CP) associated with the changes in soil suction by using the pressure cell and the effect of initial…

Abstract

Purpose

This study aims to predict the volume changes and collapse potential (CP) associated with the changes in soil suction by using the pressure cell and the effect of initial load on soil suction. Three types of gypseous soils have been experimented in this study, sandy gypseous soil from different parts of Iraq. A series of collapse tests were carried out using the oedometer device [single oedometer test (SOT) and double oedometer test (DOT)]. In addition, large-scale model with soil dimensions 700 × 700 × 600 mm was used to show the effect of water content changes in different relations (collapse with time, stress with time, suction with time, etc.).

Design/methodology/approach

A series of collapse tests were carried out using the oedometer device (SOT and DOT). In addition, a large-scale model with soil dimensions 700 × 700 × 600 mm was used to show the effect of water content changes in different relations (collapse with time, stress with time, suction with time, etc.).

Findings

The CP increases with the increasing of the void ratio for each soil. For each soil, the CP decreased when the initial degree of saturation increased. Kerbala soil with gypsum content (30%) revealed collapse value higher than Tikrit soil with gypsum content (55%) under the same initial conditions of water content and density, this is because the higher the Cu value of Kerbala soil is, the more well-graded the soil will be. Upon wetting, the smaller particles or fractions of the well-graded soil tend to fill in the existing voids, resulting in a lower void ratio as compared to the poorly graded one. Consequently, soils with high Cu value tend to collapse more than poorly graded ones. The compressibility of the soil is low when loaded under unsaturated condition, the CP for samples tested in the DOTs under stress level 800 kPa are greater than those obtained from collapse test at a stress level of 200 kPa.

Originality/value

The initial value of suction for all soils increases with initial water content decreases.

Details

World Journal of Engineering, vol. 17 no. 2
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 10 December 2019

Eric Goncalves Da Silva and Philippe Parnaudeau

The purpose of this paper is to quantify the relative importance of the multiphase model for the simulation of a gas bubble impacted by a normal shock wave in water. Both…

Abstract

Purpose

The purpose of this paper is to quantify the relative importance of the multiphase model for the simulation of a gas bubble impacted by a normal shock wave in water. Both the free-field case and the collapse near a wall are investigated. Simulations are performed on both two- and three-dimensional configurations. The main phenomena involved in the bubble collapse are illustrated. A focus on the maximum pressure reached during the collapse is proposed.

Design/methodology/approach

Simulations are performed using an inviscid compressible homogeneous solver based on different systems of equations. It consists in solving different mixture or phasic conservation laws and a transport-equation for the gas volume fraction. Three-dimensional configurations are considered for which an efficient massively parallel strategy was developed. The code is based on a finite volume discretization for which numerical fluxes are computed with a Harten, Lax, Van Leer, Contact (HLLC) scheme.

Findings

The comparison of three multiphase models is proposed. It is shown that a simple four-equation model is well-suited to simulate such strong shock-bubble interaction. The three-dimensional collapse near a wall is investigated. It is shown that the intensity of pressure peaks on the wall is drastically increased (more than 200 per cent) in comparison with the cylindrical case.

Research limitations/implications

The study of bubble collapse is a key point to understand the physical mechanism involved in cavitation erosion. The bubble collapse close to the wall has been addressed as the fundamental mechanism producing damage. Its general behavior is characterized by the formation of a water jet that penetrates through the bubble and the generation of a blast wave during the induced collapse. Both the jet and the blast wave are possible damaging mechanisms. However, the high-speed dynamics, the small spatio-temporal scales and the complicated physics involved in these processes make any theoretical and experimental approach a challenge.

Practical implications

Cavitation erosion is a major problem for hydraulic and marine applications. It is a limiting point for the conception and design of such components.

Originality/value

Such a comparison of multiphase models in the case of a strong shock-induced bubble collapse is clearly original. Usually models are tested separately leading to a large dispersion of results. Moreover, simulations of a three-dimensional bubble collapse are scarce in the literature using such fine grids.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 22 no. 8
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 31 December 2019

Sassan Eshghi and Mohammad Mahdi Maddah

Mid-rise steel moment-resisting frames (MRFs) with intermediate ductility are a major part of conventional residential buildings in Iran. According to Iranian seismic…

Abstract

Purpose

Mid-rise steel moment-resisting frames (MRFs) with intermediate ductility are a major part of conventional residential buildings in Iran. According to Iranian seismic design codes, in this resisting system, considering the strong-column/weak-beam (SCWB) criterion is not mandatory. Where a metal deck ceiling system is used, the composite action of a concrete slab and steel beams could change the collapse mechanism of the structure, especially in the MRFs with intermediate ductility. The purpose of this paper is to investigate the influence of the composite action in the seismic collapse risk of this type of structures. Seismic collapse risk assessment can be carried out by using simplified pushover-based methods. In these methods, the cyclic deterioration of an equivalent single degree of freedom (ESDoF) system must be considered when the modified Ibarra–Medina–Krawinkler is used for nonlinear modeling of MRFs. Accordingly, a modified method is developed to use in simplified collapse risk assessment process. For these purposes, two mid-rise MRFs with intermediate ductility located in Tehran have been selected as case studies. The results confirm that the composite action is very effective in collapse risk value in the steel MRFs in which their SCWB ratio is less than 1. Moreover, the proposed approach of considering the cyclic deterioration of ESDoF systems increases the accuracy of the simplified collapse assessment approaches.

Design/methodology/approach

Identifying seismically vulnerable buildings to collapse requires using robust methods. These methods can be simplified based on pushover analysis methods. An attempt was made to apply one of these approaches for steel MRFs with intermediate ductility. In these frames, the composite action of a concrete slab and steel beams could change the collapse mechanism. Here, two MRFs were investigated in order to assess this effect on collapse risk value. This process was done by modifying the SPO2IDA method as a simplified collapse capacity evaluation approach by developing a relationship to consider the cyclic deterioration effects for the ESDoF systems.

Findings

The results showed that it is necessary to consider the slab effects in the analytical model in the collapse assessment process of MRFs with intermediate ductility, especially in the condition in which the SCWB ratios of the frame are less than 1. Furthermore, by utilizing the proposed method of considering the ESDoF cyclic deterioration, the error values of the SPO2IDA program were reduced significantly. Moreover, estimating the collapse risk parameters shows that the utilized simplified method presents suitable accuracy and could be an acceptable approach to collapse risk assessment of mid-rise steel MRFs.

Originality/value

The influence of the composite action in seismic collapse risk of MRFs with intermediate ductility is investigated. Also, a modified relationship is developed to consider the deterioration effects on the ESDoF parameters used in simplified collapse risk assessment process. Also, a framework is presented for utilized methodology.

Details

International Journal of Structural Integrity, vol. 11 no. 6
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 6 February 2017

Hadi Faghihmaleki, Elmira Khaksar Najafi and Ali Hooshmand Aini

The purpose of this paper is to present a probabilistic assessment and verify the effectiveness of seismic improvement schemes against earthquake, blast and progressive…

Abstract

Purpose

The purpose of this paper is to present a probabilistic assessment and verify the effectiveness of seismic improvement schemes against earthquake, blast and progressive collapse. The probabilistic analysis is performed by taking into account the uncertainties in loading such as planar configuration and amplitude of the blast loading. A standard Monte Carlo (MC) simulation method is employed to generate various concepts of the uncertain parameters within the problem. For a given concept, various local dynamic analyses are performed within a certain range of distance, in order to quantify and locate the damage induced by impact wave on structural elements. In the next step, a limit state analysis is performed in order to investigate whether a progressive collapse mechanism forms under the acting loads or not.

Design/methodology/approach

( | ) and ( | ) are blast fragility and seismic fragility, respectively; ( ) and ( ) are annual occurrence rate of earthquake and blast, respectively. The purpose of the current study is to calculate for the primary structure as well as the retrofitted structure. Annual occurrence rate of earthquake can be calculated by using probability seismic hazard analysis for the site of interest, where the structure is located. In this paper, blast fragility and seismic fragility are defined rather differently; in other words, seismic fragility is defined as the probability of structural collapse given a specified level of seismic intensity whereas blast fragility is defined as the probability of collapse given that a significant blast event takes place. Both blast and earthquake loading conditions involve the activation of energy dissipation mechanism and, as a consequence, both can be resisted employing ductility enhancing techniques, such as column wrapping or jacketing and steel bracing.

Findings

The current paper aims to present a probabilistic assessment of progressive collapse under blast and earthquake loads. Non-dependent and incompatible events are considered to obtain a general rate of collapse. Finally, probabilistic collapse rate was obtained for a moment frame before and after modifying with convergent steel brace (CBF). The purpose of doing so is to investigate whether seismic improvement schemes can reduce collapse risk of different critical events or not.

Originality/value

Objective of the present work is to present a methodology for calculating the annual risk of collapse for a civil structure subjected to both seismic and blast loads, using a bi-hazard approach. Given that a blast event takes place, the probability of progressive collapse is calculated using a MC simulation procedure. The simulation procedure implements an efficient non-linear limit state analysis, formulated and solved as a linear programming problem. The probability of collapse caused by an earthquake event can be calculated by integrating the seismic fragility of the structure and the seismic hazard for the site.

Details

International Journal of Structural Integrity, vol. 8 no. 1
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 1 June 2000

Andrea P. Assanelli, Rita G. Toscano, Daniel H. Johnson and Eduardo N. Dvorkin

The production of steel pipes with guaranteed external collapse pressure (e.g. high collapse casings for oil wells) requires the implementation of an accurate process…

Abstract

The production of steel pipes with guaranteed external collapse pressure (e.g. high collapse casings for oil wells) requires the implementation of an accurate process control. To develop that process control it is necessary to investigate how different parameters affect the external collapse pressure of the pipes. Experimental/numerical techniques implemented to investigate the collapse behavior of steel pipes are presented. The discussion of the experimental techniques includes the description of the facilities for performing external pressure collapse tests and the description of an imperfections measuring system. The numerical techniques include 2D and 3D finite element models. The effects on the value of the pipes’ external collapse pressure of their shape, residual stresses and material properties are discussed.

Details

Engineering Computations, vol. 17 no. 4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 June 2006

Sunil Mathew, Theo G. Keith Theo G. Keith Jr and Efstratios Nikolaidis

The purpose is to present a new approach for studying the phenomenon of traveling bubble cavitation.

Abstract

Purpose

The purpose is to present a new approach for studying the phenomenon of traveling bubble cavitation.

Design/methodology/approach

A flow around a rigid, 2D hydrofoil (NACA‐0012) with a smooth surface is analyzed computationally. The Rayleigh‐Plesset equation is numerically integrated to simulate the growth and collapse of a cavitation bubble moving in a varying pressure field. The analysis is performed for both incompressible and compressible fluid cases. Considering the initial bubble radius as a uniformly distributed random variable, the probability density function of the maximum collapse pressure is determined.

Findings

The significance of the liquid compressibility during bubble collapse is illustrated. Furthermore, it is shown that the initial size of the bubble has a significant effect on the maximum pressure generated during the bubble collapse. The maximum local pressure developed during cavitation bubble collapse is of the order of 104 atm.

Research limitations/implications

A single bubble model that does not account for the effect of neighboring bubbles is used in this analysis. A spherical bubble is assumed.

Originality/value

A new approach has been developed to simulate traveling bubble cavitation by interfacing a CFD solver for simulating a flow with a program simulating the growth and collapse of the bubble. Probabilistic analysis of the local pressure due to bubble collapse has been performed.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 16 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

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