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Article
Publication date: 5 March 2021

Muhannad R. Alasiri and Mustafa Mahamid

Standard fire resistance curves such as ASTM E119 have been used for so long in structural fire practice. The issue with use of these curves that they do not represent real fire…

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Abstract

Purpose

Standard fire resistance curves such as ASTM E119 have been used for so long in structural fire practice. The issue with use of these curves that they do not represent real fire scenarios. As a result, the alternatives have been to either conduct experiments or find other tools to represent a real fire scenario. Therefore, the purpose of this paper is to understand the temperature effects resulted from a designed fire on steel beams and whether the standard fire curves represent a designed fire scenario.

Design/methodology/approach

Computational fluid dynamics (CFD) models were developed to simulate a designed fire scenario and to understand the structural responses on the beams under elevated temperatures. Consequently, the results obtained from the CFD models were compared with the results of three-dimensional (3D) non-linear finite element (FE) models developed by other researchers. The developed FE models were executed using a standard fire curve (ASTM E119). A parametric study including two case studies was conducted.

Findings

Results obtained from performing this study showed the importance of considering fire parameters such as fuel type and flame height during the thermal analysis compared to the standard fire curves, and this might lead to a non-conservative design as compared to the designed fire scenario. The studied cases showed that the steel beams experienced more degradation in their fire resistance at higher load levels under designed fires. Additionally, the models used the standard fire curves underestimated the temperatures at the early stages.

Originality/value

This paper shows results obtained by performing a comparison study of models used ASTM E119 curve and a designed fire scenario. The value of this study is to show the variability of using different fire scenarios; thus, more studies are required to see how temperature history curves can be used to represent real fire scenarios.

Details

Journal of Structural Fire Engineering, vol. 12 no. 2
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 7 August 2017

Ali Shrih, Adeeb Rahman and Mustafa Mahamid

Heavy hex structural bolts have been used in a wide range of steel structures for many years. However, these structures remain susceptible to fire damage. Conducting fire…

182

Abstract

Purpose

Heavy hex structural bolts have been used in a wide range of steel structures for many years. However, these structures remain susceptible to fire damage. Conducting fire experiments on full-scale steel structures is costly and requires specialized equipment. The main purpose of this research is to test, analyze and predict the behavior of ASTM A325 bolts under tension loading in simulated fire conditions and develop a reliable finite element model that can predict the response of similar bolts without the need for repeated testing.

Design/methodology/approach

The experimental work was conducted at the University of Wisconsin-Milwaukee, where an electric furnace was custom-built to test a bolted specimen in tension under elevated temperatures. A transient-state testing method was adopted to perform a group of tests on 12.7 mm (½”) – diameter A325 bolts. The tests were divided into two groups: the first one was used to calibrate the equipment and choose a final testing arrangement and the second group, consisting of four identical tests, was used to validate a finite element model.

Findings

The temperature-displacement and load-displacement response was recorded. The tested bolts exhibited a ductile fracture in which a cup-and-cone shaped failure surface was formed in the threaded section at the root of the nut. ASTM A325 bolts are widely used by engineers in building and bridge construction, the results of this research enable engineers to determine the behavior and strength of ASTM A325 bolts when such bolts when exposed to fire event.

Research limitations/implications

Structural bolts are used to connect structural members, and they are part of structural assembly. To study the behavior of the bolts, the bolts only were investigated in a fire simulated in a furnace. The bolts studied were not part of a structural assembly.

Practical implications

The results of this study enable engineers to evaluate the condition of ASTM A325 bolts when subjected to fire loading.

Originality value

Tests were conducted at the University of Wisconsin – Milwaukee’s structures laboratory to study the effect of fire on an ASTM A325 bolts. Many tests under fire loading have been performed by researchers on different components of steel structures, this study focuses on studying the behavior of ASTM A325 bolts which are widely used in the USA.

Details

Journal of Structural Fire Engineering, vol. 8 no. 4
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 28 February 2019

Ataollah Taghipour Anvari, Mustafa Mahamid, Michael McNallan and Mohammadreza Eslami

The purpose of this paper is to present the effect of damaged fireproofing on structural steel members. This study will show that a minor damage in fireproofing will reduce the…

234

Abstract

Purpose

The purpose of this paper is to present the effect of damaged fireproofing on structural steel members. This study will show that a minor damage in fireproofing will reduce the fire rating of members significantly. Damaged fireproofing happens in structures due to various reasons, and the question is always how effective is this fireproofing? This paper presents the results of one type of fireproofing and presents a parametric study on the size of damage and its effect on fire resistance of structural steel members.

Design/methodology/approach

The study has been performed using numerical methods, thermal and structural finite element analysis. The analysis method has been verified by experimental results.

Findings

Small fire protection damage or loss leads to significant rise of temperature at the damaged parts and causes severe fire resistance reduction of beams. The higher fire protection damage’s extension at the bottom flange of the steel beams does not have any major influence on the rate of reduction of fire resistance of the beams. Steel beams experience greater fire resistance reduction at higher load levels because of the existing of higher stresses and loads within the steel beam section.

Research limitations/implications

The study has been performed using finite element analysis, and it covers a wide range of practical sizes. However, experimental work will be performed by the researchers when funding is granted.

Practical implications

The study provides researchers and practitioners with an estimate on the effect of damaged fireproofing on fire resistance of structural steel beams.

Social implications

Understanding the effect of the effect of damaged fireproofing helps in estimating the fire resistance of structural steel members, which may protect collapses and disasters.

Originality/value

The research is original; extensive literature review has been performed, and this research is original.

Details

Journal of Structural Fire Engineering, vol. 10 no. 1
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 4 August 2017

Ali Shrih, Adeeb Rahman and Mustafa Mahamid

Nuts and bolts have been used as fasteners of steel structures for many years. However, these structures remain susceptible to fire damage. While conducting fire experiments on…

183

Abstract

Purpose

Nuts and bolts have been used as fasteners of steel structures for many years. However, these structures remain susceptible to fire damage. While conducting fire experiments on steel structures is sometimes necessary, to better understand their behavior, such experiments remain costly and require specialized equipment and testing facilities. This paper aims to present a highly accurate three-dimensional (3D) finite element (FE) model of ASTM A325 bolt subjected to tension loading under simulated fire conditions. The FE model is compared to the results of experimental testing for verification purposes and is proven to predict the response of similar bolts up to certain temperatures without the need for repeated testing.

Design/methodology/approach

A parametric 3D FE model simulating tested specimens was constructed in the ANSYS Workbench environment. The model included the intricate details of the bolt and nut threads, as well as all the other components of the specimens. A pretension load, a tension force and a heat profile were applied to the model, and a nonlinear analysis was performed to simulate the experiments.

Findings

The results of the FE model were in good agreement with the experimental results, deviations of results between experimental and FE results were within acceptable range. This should allow studying the behavior of structural bolts without the need for expensive testing.

Originality/value

Detailed 3D FE models have been created by the authors have been created to study the behavior of structural bolts and compared with experiments conducted by the authors.

Details

Journal of Structural Fire Engineering, vol. 9 no. 1
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 23 January 2019

Mustafa Mahamid, Ataollah Taghipour Anvari, Ines Torra-Bilal, Tom Brindley and Michael McNallan

The purpose of this paper is to investigate different types of fire on structural steel members with damaged fireproofing. Two types of fire scenarios are considered, ASTM E119…

216

Abstract

Purpose

The purpose of this paper is to investigate different types of fire on structural steel members with damaged fireproofing. Two types of fire scenarios are considered, ASTM E119 fire and Hydrocarbon fire. In industrial facilities such as oil refineries, certain units maybe subjected to hydrocarbon fire, and its effect might be different than standard fire. The purpose of this study is to compare both types of fire scenarios on steel beams with damaged fireproofing and determine the fire rating of the damaged beams under each fire scenario.

Design/methodology/approach

The study is performed using computational methods, thermal-stress finite element analysis that is validated with experimental results. The results of practical beam sizes and typical applied loads in such structures have been plotted and compared with steel beams with non-damaged fireproofing.

Findings

The results show significant difference in the beam fire resistance between the two fire scenarios and show the fire resistance for beam under each case. The study provides percentage reduction in fire resistance under each case for the most commonly used cases in practice under different load conditions.

Originality/value

Extensive literature search has been performed by the authors, and few studies were found relevant to the topic. The question this study answers comes up regularly in practice. There are no standards to codes that address this issue.

Details

Journal of Structural Fire Engineering, vol. 10 no. 2
Type: Research Article
ISSN: 2040-2317

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Article
Publication date: 2 March 2015

Abdulaziz M. Jarkas and Theodore C. Haupt

The purpose of this paper is to identify, explore, rank the relative importance and determine the prevalent allocation response trends of the major construction risk factors…

3409

Abstract

Purpose

The purpose of this paper is to identify, explore, rank the relative importance and determine the prevalent allocation response trends of the major construction risk factors considered by general contractors operating in the State of Qatar.

Design/methodology/approach

A structured questionnaire survey comprising 37 potential risk factors was distributed to a statistically representative sample of contractors. The influence ranks of the factors explored were determined using the “Relative Importance Index (RII)” technique, whereas the prevalent trend of contractors’ attitudes toward risk allocation of each factor investigated was quantified and expressed as a percentage, based on the number of respondents who selected a specific option, in relation to the total number of respondents.

Findings

The results obtained indicate that risks related to the “client” group are perceived as most critical, followed by the “consultant”, “contractor” and “exogenous” group-related factors, respectively. The outcomes further show that the “transfer” option is the contractors’ prevalent response to “client” and “consultant”-related risks, while the “retention” decision is the principal pattern linked to “contractor” and “exogenous” group-related risk factors.

Research limitations/implications

The dominant respondents’ perception that the crucial construction risks are related to clients and consultants suggests that these two parties have an essential role in controlling the negative ramifications of the associated factors.

Practical implications

The findings suggest that increasing designers’ awareness of the significant effect of applying the constructability concept can considerably help reducing the risks concomitant of the construction operation. Policy makers may contribute, moreover, in alleviating the risk of incompetent technical staff and operatives’ employment by controlling the migration of inexperienced and unskilled construction workforce into the State.

Originality/value

Given the knowledge gap for the major construction risk factors considered by general contractors in Qatar, the results reported in this study can provide clients, industry practitioners and policy makers with guidance to effectively manage the significant risks determined, which can further assist in achieving a reasonable level of competitiveness and cost-effective operation.

Details

Journal of Engineering, Design and Technology, vol. 13 no. 1
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 3 April 2017

Ibrahim Mahamid

This study aims at identifying the main causes of change orders in highway construction projects, determining the factors that affect rework in highway construction projects…

578

Abstract

Purpose

This study aims at identifying the main causes of change orders in highway construction projects, determining the factors that affect rework in highway construction projects, examining the relationship between change orders and rework and at developing a predictive model that will determine the impact of change orders on rework in highway construction projects in Palestine.

Design/methodology/approach

A questionnaire survey was used to identify the main change order causes and rework causes from the perspectives of contractors and consultants. The questionnaire contained 16 causes of change orders and 19 causes of rework which had been identified from the literature reviewed. The study also identifies the impact of change orders on rework based on data comprising 22 highway construction projects implemented in Palestine. Both descriptive and inferential statistics were used in analyzing the data.

Findings

The study concluded that the five most common causes of change orders can be identified as: change of project scope by owner (additional – enhancement), lack of coordination between construction parties; owner’s financial difficulties, change in materials, and errors and omissions in design. The study has also established that among the various factors that causes rework, non-conformance with specification requirements, scope changes, late design changes, lack of labor experience, lack of labor skills and improper subcontractor selection top the list. Using regression analysis, the results reveal a significant relationship between change orders and rework cost in highway construction projects in Palestine.

Practical implications

By ranking the various change orders causes and rework causes from the perspectives of consultants and contractors, the study provides a fresh perspective on an old chronic problem in the construction sector. This study has provided evidence on the most significant change orders causes and rework causes in the Palestinian highway construction, as well as the impact of change orders or rework on constructions sites. Finally, although this study is specific to the country of Palestine, its results can be applicable to other developing countries facing similar problems in their public construction sectors.

Originality/value

The results address the common causes of change orders and reworks in highway construction projects in Palestine. The results also address the relation between change orders and rework cost based on data collected from highway construction projects implemented in the West Bank in Palestine. This study is the first study conducted in the West Bank in Palestine to identify the change orders and reworks causes in highway construction projects.

Details

Journal of Financial Management of Property and Construction, vol. 22 no. 1
Type: Research Article
ISSN: 1366-4387

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Article
Publication date: 5 October 2022

Parvathidevi A. and Naga Satish Kumar Ch

This study aims to assess the efficacy of thermal analysis of concrete slabs by including different insulation materials using ANSYS. Regression equations were proposed to predict…

199

Abstract

Purpose

This study aims to assess the efficacy of thermal analysis of concrete slabs by including different insulation materials using ANSYS. Regression equations were proposed to predict the thermal conductivity using concrete density. As these simulation and regression analyses are essential tools in designing the thermal insulation concretes with various densities, they sequentially reduce the associated time, effort and cost.

Design/methodology/approach

Two grades of concretes were taken for thermal analysis. They were designed by replacing the natural fine aggregates with thermal insulation aggregates: expanded polystyrene, exfoliated vermiculite and light expanded clay. Density, temperature difference, specific heat capacity, thermal conductivity and time were measured by conducting experiments. This data was used to simulate concrete slabs in ANSYS. Regression analysis was performed to obtain the relation between density and thermal conductivity. Finally, the quality of the predicted regression equations was assessed using root mean square error (RMSE), mean absolute error (MAE), integral absolute error (IAE) and normal efficiency (NE).

Findings

ANSYS analysis on concrete slabs accurately estimates the thermal behavior of concrete, with lesser error value ranges between 0.19 and 7.92%. Further, the developed regression equations proved accurate with lower values of RMSE (0.013 to 0.089), MAE (0.009 to 0.088); IAE (0.216 to 5.828%) and higher values of NE (94.16 to 99.97%).

Originality/value

The thermal analysis accurately simulates the experimental transfer of heat across the concrete slab. Obtained regression equations proved helpful while designing the thermal insulation concrete.

Details

World Journal of Engineering, vol. 21 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 2 September 2013

Ibrahim Mahamid

– The study aims at identifying the factors affecting labor productivity in building construction projects in the West Bank in Palestine from contractors’ viewpoint.

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Abstract

Purpose

The study aims at identifying the factors affecting labor productivity in building construction projects in the West Bank in Palestine from contractors’ viewpoint.

Design/methodology/approach

To do so, 59 contractors working in building construction completed a structured questionnaire survey and the factors were ranked according to their levels of influence. In all, 31 factors were identified through literature review. These factors were grouped into five groups: labor, managerial, materials and equipments, environmental, and financial.

Findings

The analysis of the identified 31 factors indicates that the top-five factors negatively affecting labor productivity in building construction are: rework, lack of cooperation and communication between construction parties, financial status of the owner, lack of labor experience, and lack in materials.

Originality/value

This study is original and has not been published before. The findings and recommendations of this study are very useful and helpful for the local firms and the international firms who are planning to do works in the West Bank

Details

Engineering, Construction and Architectural Management, vol. 20 no. 5
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 9 November 2015

Siti Mashitoh Mahamood and Asmak Ab Rahman

The purpose of this article is to highlight the importance of waqf in financing higher education. Nowadays, higher education is costly and this has prevented students, especially…

7254

Abstract

Purpose

The purpose of this article is to highlight the importance of waqf in financing higher education. Nowadays, higher education is costly and this has prevented students, especially those who are self-financed, from accessing such learning environments. This paper offer an alternative solution to relieve such a situation, namely, through the application of an endowment-based or waqf educational institution. The study suggests a way to establish an endowment university by concentrating the discussion on the concept and principles of its establishment, as well as sharing the experiences of the Malaysian waqf universities and the Turkish Foundation Universities/Vakif Üniversitesi in financing their universities using waqf, i.e. a pious endowment instrument.

Design/methodology/approach

The empirical data were mainly collected using in-depth interviews with the universities’ higher management authorities and some of the members of the board of trustees.

Findings

The findings show that the role of waqf or pious endowment is significant in providing financial assistance to their communities as well as strengthening their academic quality. In addition, tawhidic epistemology together with morality and ethics have influenced waqf donors or founders to donate their wealth and property to enrich and sustain universities and higher education.

Originality/value

This article provides the experiences of the Malaysian Waqf Universities and the Turkish Foundation Universities/Vakif Üniversitesi in financing their universities using waqf. It also contains some good examples from the experience of several earlier Islamic civilizations, in particular those of the Ottoman Empire and the Mamluk Sultanate of Egypt. In addition, examples of the implementation of waqf and endowment-based universities in the UK and USA as well as the Al-Azhar University of Egypt is also included.

Details

Humanomics, vol. 31 no. 4
Type: Research Article
ISSN: 0828-8666

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