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Article
Publication date: 1 April 1987

Edmund Booth

Introduction In a previous paper, I discussed the techniques for ensuring the earthquake resistance of new buildings. Experience of past earthquakes demonstrates that…

Abstract

Introduction In a previous paper, I discussed the techniques for ensuring the earthquake resistance of new buildings. Experience of past earthquakes demonstrates that incorporating the methods and advances of the last 30 years in the planning, design and construction of new buildings is the best way of minimising loss of life and investment during major earthquakes.

Details

Structural Survey, vol. 5 no. 4
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 1 February 2004

Abstract

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Structural Survey, vol. 22 no. 1
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 10 September 2019

Wojciech Piotr Adamczyk, Marcin Gorski, Ziemowit Ostrowski, Ryszard Bialecki, Grzegorz Kruczek, Grzegorz Przybyła, Rafal Krzywon and Rafal Bialozor

Large structural objects, primarily concrete bridges, can be reinforced by gluing to their stretched surface tapes of fiber-reinforced polymer (FRP). The condition for this…

Abstract

Purpose

Large structural objects, primarily concrete bridges, can be reinforced by gluing to their stretched surface tapes of fiber-reinforced polymer (FRP). The condition for this technology to work requires the quality of the bonding of FRP and the concrete to be perfect. Possible defects may arise in the phase of construction but also as a result of long-term fatigue loads. These defects having different forms of voids and discontinuities in the bonding layer are difficult to detect by optical inspection. This paper aims to describe the development of a rapid and nondestructive method for quantitative assessment of the debonding between materials.

Design/methodology/approach

The applied technique belongs to the wide class of active infrared (IR) thermography, the principle of which is to heat (or cool) the investigated object, and determine the properties of interest from the recorded, by an IR camera, temperature field. The methodology implemented in this work is to uniformly heat for a few seconds, using a set of halogen lamps, the FRP surface attached to the concrete. The parameter of interest is the thermal resistance of the layer separating the polymer tape and the concrete. The presence of voids and debonding will result in large values of this resistance. Its value is retrieved by solving an inverse transient heat conduction problem. This is accomplished by minimizing, in the sense of least squares, the difference between the recorded and simulated temperatures. The latter is defined as a solution of a 1D transient heat conduction problem with the already mentioned thermal resistance treated as the only decision variable.

Findings

A general method has been developed, which detects debonding of the FRP tapes from the concrete. The method is rapid and nondestructive. Owing to a special selection of the compared dimensionless measured and simulated temperatures, the method is not sensitive to the surface quality (roughness and emissivity). Measurements and calculation may be executed within seconds. The efficiency of the technique has been shown at a sample, where the defects have been artificially introduced in a controlled manner.

Originality/value

A quantitative assessment procedure which can be used to determine the extent of the debonding has been developed. The procedure uses inverse technique whose result is the unknown thermal resistance between the member and the FRP strip.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 30 April 2021

Arturo Cruz, Vaughan Coffey, Tommy H.T. Chan and Miljenka Perovic

This paper aims to set out the role of engineers in heritage conservation and investigates and evaluates the proposed available tools, technology and innovations that are…

Abstract

Purpose

This paper aims to set out the role of engineers in heritage conservation and investigates and evaluates the proposed available tools, technology and innovations that are currently available in the civil engineering sector that can be applied in heritage conservation.

Design/methodology/approach

As society has become more aware of the grandeur of heritage spaces and structures, there is increasing pressure to preserve historic buildings. But, it is the economic cost of maintaining this important heritage legacy that has become the prime consideration of every state in Australia. Dedicated intelligent monitoring systems supplementing the traditional building inspections will enable the involved and interested stakeholders to carry out not only timely reactive response, but also to plan the maintenance of such buildings in a more vigilant and systematic manner. This will, in future, help to prevent further degradation of heritage buildings, which is very costly, often difficult and sometimes impossible to address if neglected. Savings in time and resources can be achieved, but only if a building's pathological monitoring and inspection results are on hand for use to guide major decisions to be made on how to best prevent further decay, or to save an important historical structure or building fabric.

Findings

The emergence of technological tools will enable the realization of a maintenance-focused conservation model. However, aside from the cost, these tools are still experimental in nature. These technologies are yet to be applied within the conservation industry with hopes of creating an easier and economically effective systematic method of heritage conservation.

Originality/value

The paper discusses the emerging tools and technologies in easing the monitoring aspect of a maintenance-focused conservation model.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2044-1266

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Article
Publication date: 4 January 2011

Valentina Salomoni, Gianluca Mazzucco, Carlo Pellegrino and Carmelo Majorana

The purpose of this paper is to investigate the bond behaviour between fiber reinforced polymer (FRP) sheets and concrete elements, starting from available experimental…

Abstract

Purpose

The purpose of this paper is to investigate the bond behaviour between fiber reinforced polymer (FRP) sheets and concrete elements, starting from available experimental evidences, through a calibrated and upgraded 3D mathematical‐numerical model.

Design/methodology/approach

The complex mechanism of debonding/peeling failure of FRP reinforcement is studied within the context of damage mechanics to appropriately catch transversal effects and developing a more realistic and comprehensive study of the delamination process. The FE ABAQUS© code has been supplemented with a numerical procedure accounting for Mazars's damage law inside the contact algorithm.

Findings

It has been shown that such an approach is able to catch the delamination evolution during loading processes as well.

Originality/value

A Drucker‐Prager constitutive law is adopted for concrete whereas FRP elements are assumed to behave in a linear‐elastic manner, possibly undertaking large strains/displacements. Surface‐to‐surface contact conditions have been applied between FRP and adjacent concrete, including the enhancement given by the strain‐softening law according to Mazars' damage model. The procedure has been introduced to describe the coupled behaviour between concrete, FRP and adhesive resulting in specific bonding‐debonding features under different load levels.

Details

Engineering Computations, vol. 28 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 January 1985

J.S. Tasker

Reinforced concrete is a very durable material, often specified because of the expectations of a long maintenance‐free life. However, it is also an easily abused material…

Abstract

Reinforced concrete is a very durable material, often specified because of the expectations of a long maintenance‐free life. However, it is also an easily abused material. It derives its strength from chemical change and both its physical and its chemical form provide corrosion protection to the reinforcement. It is, therefore, highly sensitive to the contents of the mix and in particular to any additives or pollutants which might affect the chemical composition.

Details

Structural Survey, vol. 3 no. 1
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 8 November 2011

Gursans Guven and Esin Ergen

This paper aims to identify the local information items that are needed by search and rescue (S&R) teams for an effective disaster response following an earthquake…

Abstract

Purpose

This paper aims to identify the local information items that are needed by search and rescue (S&R) teams for an effective disaster response following an earthquake. Currently, it is a challenging and time‐consuming task to collect most of this information from a disaster environment. It was envisioned that the local information identified can be stored on distributed databases that are placed in the buildings and will be used to improve S&R operations.

Design/methodology/approach

The information items are obtained through a literature review and via interviews conducted with experts from disaster response organizations. The data collected were triangulated to generate a data model, which was then validated internally and externally by expert feedback.

Findings

A data model including a detailed list of information items required during S&R operations was generated, along with justification of the information needs. The findings show that not only information related to buildings, but also other information related to the residents and the contents of the buildings are needed, such as residents' health information, and hazardous materials and their specific locations.

Practical implications

The data model presented can be used by researchers to further develop systems that can be used during an earthquake.

Originality/value

Previous studies have only provided a list of some important local information groups to be stored; however, they do not include in‐depth studies on the information needs of S&R teams following an earthquake. In this paper, information needs were fully explored and elaborated, and a data model was developed covering information items required for effective earthquake S&R.

Details

Disaster Prevention and Management: An International Journal, vol. 20 no. 5
Type: Research Article
ISSN: 0965-3562

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Article
Publication date: 10 December 2019

Tie-Lin Chen, Wenbin Tao, Wenjun Zhu and Mozhen Zhou

Near-surface mounted (NSM) fiber-reinforced polymer (FRP) rod is extensively applied in reinforced concrete (RC) structures. The mechanical performances of NSM FRP…

Abstract

Purpose

Near-surface mounted (NSM) fiber-reinforced polymer (FRP) rod is extensively applied in reinforced concrete (RC) structures. The mechanical performances of NSM FRP-strengthened RC structures depend on the bond behavior between NSM reinforcement and concrete. This behavior is typically studied by performing pull-out tests; however, the failure behavior, which is crucial to the local debonding process, is not yet sufficiently understood.

Design/methodology/approach

In this study, a three-dimensional meso-scale finite element method considering the cohesion and adhesion failures is presented to model the debonding failure process in pull-out tests of NSM FRP rod in concrete. The smeared crack model is used to capture the cohesion failures in the adhesive or concrete. The interfacial constitutive model is applied to simulate the adhesion failures on the FRP-adhesive and concrete-adhesive contact interfaces.

Findings

The present method is first validated by two simple examples and then applied to a practical NSM FRP system. This work studied in detail the debonding process, the bond failure types, the location of peak bond stress, the transmitting deformation in adhesive and the morphology of contact zone. The developed method provides a practical and convenient tool applicable for further investigations on the debonding mechanism for the NSM FRP rod in concrete.

Originality/value

A three-dimensional meso-scale finite element method considering the cohesion and adhesion failures is presented to model the debonding failure in NSM FRP-strengthened RC structures. The smeared crack model and the interfacial constitutive model are introduced to develop a convenient approach to analyze the failures in adhesive, concrete and related interfaces. The developed numerical method is applicable for studying the debonding process, the bond failure types, the location of peak bond stress, the transmitting deformation in adhesive and the morphology of contact zone in detail.

Details

Engineering Computations, vol. 37 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 2 October 2018

Yefei Yang, Antonio K.W. Lau, Peter K.C. Lee, Andy C.L. Yeung and T.C. Edwin Cheng

The Chinese Government encourages firms to diffuse their operational-level environmental management (EM) into their organization’s mission and strategy to develop…

Abstract

Purpose

The Chinese Government encourages firms to diffuse their operational-level environmental management (EM) into their organization’s mission and strategy to develop strategic EM to promote sustainable development. The purpose of this paper is to utilize two concepts of institutional theory (isomorphic pressures and decoupling behavior) to assess how different institutional forces arising from Chinese macro-level factors (market pressure, business turbulence, legal voids, carbon policy, structural-level governmental interference and guanxi with government) influence the efficacy of strategic EM.

Design/methodology/approach

In partnership with a major consulting firm in China, the authors collect multi-informant survey data from 183 manufacturing firms drawn from a variety of industries for testing the hypotheses posited.

Findings

The efficacy of strategic EM in the sampled firms is confirmed by the positive association with environmental performance. The authors also find that the efficacy of strategic EM is weakened by market pressure, business turbulence and legal voids, whereas it is strengthened by structural-level governmental interference. However, carbon policy and guanxi with government do not impact it significantly.

Research limitations/implications

To extend the findings on the environmental importance of strategic EM, future research can develop and validate a management framework to guide the adoption of strategic EM. With regard to the four valid macro-level factors influencing the efficacy of strategic EM, future research can identify the reasons (e.g. conflict with corporate functions) behind them to aid manufacturers to mitigate their negative influence or enhance the positive influence on strategic EM.

Social implications

China’s Government and its manufacturers (or those sharing a similar institutional environment) can expand the scope of their EM efforts from operational-level EM practices to strategic EM. The findings on the valid macro-level factors have led to practical suggestions for government bodies and manufacturers to improve the efficacy of strategic EM adoption. Overall, the implications help achieve the higher levels of firm-level environmental performance and alleviate the global pollution problem.

Originality/value

A particular value of this work lies in the demonstration of combining institutional theory (organization decoupling, isomorphic pressures) with practical consideration such as guanxi with government in the particular institutional environment of China to help address an important and context-related problem, environmental performance.

Details

International Journal of Operations & Production Management, vol. 39 no. 1
Type: Research Article
ISSN: 0144-3577

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Article
Publication date: 12 June 2017

Danie Roy Anasco Bastin, Umesh Kumar Sharma and Pradeep Bhargava

The main aim of this research was to investigate the effectiveness of various strengthening techniques in restoring the structural performance of reinforced concrete (RC…

Abstract

Purpose

The main aim of this research was to investigate the effectiveness of various strengthening techniques in restoring the structural performance of reinforced concrete (RC) beams damaged by elevated temperatures.

Design/methodology/approach

Three different strengthening techniques, namely, high-strength fibre reinforced concrete (HSFRC), ferrocement (FC) jacketing and externally bonded fibre-reinforced polymer (FRP) were used. Series of RC beams were casted, heated, strengthened and tested to investigate the influence of various variables. The variables of the study were type of strengthening and level of heat damage.

Findings

Externally bonded FRP was found to be the best among the various techniques, especially with respect to strength and stiffness restoration. On the contrary, the FRP strengthening was not that effective in restoring the energy absorption capacity of beams compared to HSFRC and FC techniques of strengthening. The chosen strengthening techniques were able to restore the failure mode of beams to flexural failure, which was found to have changed to shear failure in case of heated unstrenghthened beams.

Originality/value

This research program has contributed to the fundamental understanding of designing post fire retrofit solutions for RC beams.

Details

Journal of Structural Fire Engineering, vol. 8 no. 2
Type: Research Article
ISSN: 2040-2317

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