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1 – 10 of 248Manoochehr Najmi, Rahim Ehsani, Ahmad Sharbatoghlie and Mohammad Saidi‐Mehrabad
The purpose of this paper is to develop an integrated dynamic model, based on empirical findings, which can be used in research centers for evaluating the performance of research…
Abstract
Purpose
The purpose of this paper is to develop an integrated dynamic model, based on empirical findings, which can be used in research centers for evaluating the performance of research projects by using multiple attribute utility theory.
Design/methodology/approach
In developing the model, the measures by which the performance of research projects could be evaluated are identified by Delphi method and group decision making. These measures are categorized into three general success factors of time, cost and quality. Then a multi‐attribute utility function is applied to integrate these dimensions to determine the utility resulting from the performance of the project.
Findings
Through literature review it is evident that some evaluation techniques such as checklists, scoring models, analytical hierarchy process and engineering economic techniques have been developed for evaluating performance of projects. The present model complements and improves upon the existing models.
Research limitations/implications
The parameters of model are determined based on research center's policy but they may be changed for other research centers. So the model depends on the expert's view. The model is not considered advantageous in situations where project gets ahead of program.
Practical implications
The model is tested in an engineering research institute and the comparison is made with the results of the existing models.
Originality/value
The advantage of proposed model is its flexibility, dynamism and the capability to revise the model based on any changes in the objectives and policies of the research center.
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Yasmin Murad, Haneen Abdel-Jabar, Amjad Diab and Husam Abu Hajar
The purpose of this study is to develop two empirical models that predict the shear strength of exterior beam-column joints exposed to monotonic and cyclic loading using Gene…
Abstract
Purpose
The purpose of this study is to develop two empirical models that predict the shear strength of exterior beam-column joints exposed to monotonic and cyclic loading using Gene expression programming (GEP).
Design/methodology/approach
The GEP model developed for the monotonic loading case is trained and validated using 81 data test points and that for cyclic loading case is trained and validated using 159 data test points that collected from different 9 and 39 experimental programs, respectively. The parameters that are selected to develop the cyclic GEP model are concrete compressive strength, joint aspect ratio, column axial load and joint transverse reinforcement. The monotonic GEP model is developed using concrete compressive strength, column depth, joint width and column axial load.
Findings
GEP models are proposed in this paper to predict the joint shear strength of beam-column joints under cyclic and monotonic loading. The predicted results obtained using the GEP models are compared to those calculated using the ACI-352 code formulations. A sensitivity analysis is also performed to further validate the GEP models.
Originality/value
The proposed GEP models provide an accurate prediction for joint shear strength of beam-column joints under cyclic and monotonic loading that is more fitting to the experimental database than the ACI-352 predictions where the GEP models have higher R2 value than the code formulations.
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Y.N. Ziraba, M.H. Baluch, A.M. Sharif, G.J. Al—Sulaimani, A.K. Azad and I.A. Basunbul
This paper presents a finite element model for analysis of damaged RCbeams strengthened or repaired by externally bonding glass fibre reinforcedplastics (GFRP) on the tension side…
Abstract
This paper presents a finite element model for analysis of damaged RC beams strengthened or repaired by externally bonding glass fibre reinforced plastics (GFRP) on the tension side of the beams. The salient features include: (i) the introduction of a thin, six—noded element to simulate behaviour of the concrete/epoxy glue/GFRP interface and )ii( a scheme of loading a virgin RC beam to a prescribed displacement to simulate damage, unloading and then reloading the damaged RC beam fortified by an externally bonded GFRP plate. Results are presented for RC beams repaired by plates of varying thickness and a transmutation of failure mode is noted from classical flexure for the case of external reinforcement in the form of thin GFRP plates to a unique concrete cover rip off failure for thicker GFRP plates and not predicted by the ACI shear strength formula for diagonal tension failure of unplated RC beams of similar geometry.
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A. Mohamadi Sani, M.R. Ehsani and M. Mazaheri Asadi
Fungal growth on UF‐Feta cheese is one of the most important factors of consumer dissatisfaction in Iran. Propionibacterium shermanii metabolites was used as a biopreservative to…
Abstract
Purpose
Fungal growth on UF‐Feta cheese is one of the most important factors of consumer dissatisfaction in Iran. Propionibacterium shermanii metabolites was used as a biopreservative to retard this inconvenient. This research was done to determine the concentration of the metabolite that increases cheese shelf life with no adverse effect on sensory properties.
Design/methodology/approach
The cheese was manufactured according to the methods used in the Iranian UF‐Feta cheese dairy plants. The metabolite was used in the order of 0.5 and 1 per cent (w/w) of retentate weight. After incubation while reaching the required pH, cheese samples were stored at two temperatures including 4 and 25 degree C in which analysis was done during a period of 90 and 70 days respectively. Effect of the metabolite on shelf life (absence of visible fungi growth), total viable fungi, microbial load, pH as well as sensory properties including taste, odour, colour and overall acceptability was compared with the control (untreated sample).
Findings
Results showed that the shelf life duration of the cheese was extended by approx. 35–43 per cent. Total viable fungi was most efficiently reduced using the metabolite but there was no significant differences in microbial load. Addition of the metabolite didn’t affect pH of cheese at either temperatures compared with control. Results of sensory evaluation showed that the taste and odour of cheese containing 0.5 per cent of the metabolite was preferred as compare to the others (p<0.1). The intervension had no effect no effect on colour scores of cheese. The texture of control was better than the others (p<0.1).
Originality/value
In UF‐Feta cheese, the presence of fungi represents a major concern for cheese manufacturers. The results indicate that the fungal growth can be minimized using Propionibacterium shermanii metabolites without undesirable effects on sensory properties. The potential of the metabolite to inhibit yeast growth on UF‐Feta cheese was a new finding in this research.
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R.V. Balendran, T.M. Rana and A. Nadeem
Presents an overview and discusses the applications of fibre reinforced polymer (FRP) sheets and plates in the strengthening of concrete structures. An insight may be obtained…
Abstract
Presents an overview and discusses the applications of fibre reinforced polymer (FRP) sheets and plates in the strengthening of concrete structures. An insight may be obtained from the discussions made to enhance the use of these techniques for productive use. In addition, selected case studies have been furnished where FRP materials have been used for repairing/retrofitting, emphasizing the application of different types of FRP materials in strengthening concrete structures. Concludes that the use of FRP material is rapidly gaining pace and replacing the traditional steel or metal based materials due to its enhanced properties and cost effectiveness.
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Djeffal Mohamed, Merdas Abdelghani and Douara Taha Hocine
Although the reinforcement of concrete and brick masonry with fiber-reinforced polymer (FRP) has been extensively researched, its application and impact on natural stone…
Abstract
Purpose
Although the reinforcement of concrete and brick masonry with fiber-reinforced polymer (FRP) has been extensively researched, its application and impact on natural stone, especially in historic preservation, have received less attention. This study aims to examine the bond-slip characteristics of carbon fiber-reinforced polymer (CFRP) with two types of natural stone masonry, aiming to enhance their effectiveness in reinforcing historic structures. The stones studied include one from the Chouf-Lekdad region (A) and another from a historic structure in Sétif City (B). Both stones were strengthened using CFRP and carbon fiber fabric (CFF) through near-surface mount (NSM) and external bonding (EBR) techniques.
Design/methodology/approach
The interaction was assessed during the pull-out test by analyzing the stress transfer mechanisms, adhesion and deformation. This study also examines the effects of the following parameters on the bond between CFRP and stone: type of stone (A and B), type of reinforcement (plat CFRP and CFF), various notch shapes and sizes (bp, tp and Lb), and reinforcement techniques (NSM and EBR).
Findings
This study demonstrated the practicality and effectiveness of enhancing natural stone masonry of old buildings by integrating NSM and EBR techniques with CFRP. With a bond length of 30 mm, the pull-out force correlates with the strength of the stone. This indicates the importance of stone strength in obtaining better adhesion. The CFF–resin interface is more cohesive than the CFRP plate–resin interface because the resin penetrates the flexible CFF strip, ensuring better adhesion. In contrast, the CFRP plate interface is rigid and smooth. The results suggest that natural stone–CFRP adhesion is more effective than CFRP bonded to concrete and brick masonry due to the stone's strong resistance.
Originality/value
This experimental investigation provides new study into the bond-slip behavior of CFRP-reinforced natural stone masonry, filling the gap in existing research. The findings offer useful direction for creating FRP strengthening solutions that are specifically adapted to the properties of natural stone used in historic constructions. This study helps to improve preservation procedures by guiding the selection of reinforcing techniques, such as NSM versus EBR, and finding ideal bond lengths. This work's novelty stems from its ability to improve the structural integrity of culturally significant buildings while preserving their historical authenticity.
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M. Ait Ameur Meziane, S. Benyoucef, A. Tounsi and E.A. Adda Bedia
Fibre‐reinforced plastic (FRP) materials have been recognised as new innovative materials for concrete rehabilitation and retrofit. Since concrete is poor in tension, a beam…
Abstract
Fibre‐reinforced plastic (FRP) materials have been recognised as new innovative materials for concrete rehabilitation and retrofit. Since concrete is poor in tension, a beam without any form of reinforcement will fail when subjected to a relatively small tensile load. Therefore, the bonding of FRP plate to reinforced concrete (RC) structure is an effective solution to increase its overall strength. In such plated beams, tensile forces develop in the bonded plate and these have to be transferred to the original beam via interfacial shear and normal stresses. Consequently, the debonding of FRP plates bonded to reinforced concrete beams is believed to be initiated by the stress concentration in the adhesive layer. Accurate predictions of the interfacial stresses are prerequisite for designing against debonding failures. In the present analysis, a simple theoretical model to estimate shear and normal stresses is proposed, including the variation in FRP plate fibre orientation. The solution shows significant shear and normal stresses concentration at the plates end. A parametrical study is carried out to show the effects of some design variables, e.g., thickness of adhesive layer and FRP plate, and the distance from support to cut ‐ off end of bonded plates.
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Preeti Dwivedi, Vijit Chaturvedi and Jugal Kishore Vashist
This research focuses on suggesting an optimized model for selecting best employees using advanced multi-criteria decision making method to a supply chain firm, who is planning to…
Abstract
Purpose
This research focuses on suggesting an optimized model for selecting best employees using advanced multi-criteria decision making method to a supply chain firm, who is planning to start a new cold chain business vertical.
Design/methodology/approach
Study has been conducted in a supply chain firm in North India, who wants to expand its business with the help of efficient team members. In total 38 applicants were considered for the study, as selected by the firm after initial screening from pool of talent. AHP-LP and TOPSIS-LP integrated approach were applied separately for evaluation and implementation of personnel selection model. Further, both the approaches were compared to find the best fit and optimized model.
Findings
As per the findings, both AHP and TOPSIS can be used to select the best candidate among the alternatives available. TOPSIS was found easier to implement as it involves ranking of applicants with respect to each skills required for respective job profile only once, whereas AHP involves pair-wise comparison among candidates with respect to each skills required for respective job profile and normalization of each comparison, resulting in the formation of number of comparison matrices. However, AHP is more reliable as it considers consistency check for each level of pair-wise comparison. Hence, there is a chance to avoid or revise the human judgment error. Integrated ranking and optimization approach minimizes the cost by suggesting the relevant positions to be filed to make an efficient team.
Research limitations/implications
Group of interviewers are involved in the decision-making process, hence there are chances of biasness in ranking method which can influence the group decision. Research is limited to a particular geography of North India therefore needs to be tested for other regions also in order to generalize. The research will help the third party logistics (3PL) and other related firms in efficient team selection.
Originality/value
The researcher focuses on formalizing a method for potential candidate selection by considering the constraints of the organization. It has been observed that limited researches have been done on the application of AHP-LP or TOPSIS-LP integrated approach for selection process. Hence, this research proposes two integrated ranking-optimization method and suggests the best fit by comparing both the approaches.
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Achintya Haldar and Ali Mehrabian
Structural engineering as a part of civil engineering has over 5,000 years of distinguished history, as documented in this paper. An attempt is made in this paper to define…
Abstract
Purpose
Structural engineering as a part of civil engineering has over 5,000 years of distinguished history, as documented in this paper. An attempt is made in this paper to define structural engineering as it exists at present, then some historical structures are identified.
Design/methodology/approach
The advances of structural engineering are discussed in chronological order, encompassing the development of the concept, analysis, the use of innovative construction materials, and construction. The developments which necessitated the change of design philosophies are presented, and the current status of structural engineering is discussed in terms of several specific topics. Opportunities and challenges in the new millennium in structural engineering are then presented in terms of education, service to society, and research.
Findings
In the past, structural engineering always met the challenges it faced. It helped to improve our quality of life, and its role in society is not expected to change in the near future.
Originality/value
The paper has provided an over‐view of this important profession – from ancient history to the present day. Based on research over several decades it offers a prediction of the direction in which this profession and the academic research that underpins it is likely to take in the future.
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R.V. Balendran, T.M. Rana, T. Maqsood and W.C. Tang
This paper presents an overview and discusses the applications of fibre reinforced polymer (FRP) bars as reinforcement in civil engineering structures. Following a discussion of…
Abstract
This paper presents an overview and discusses the applications of fibre reinforced polymer (FRP) bars as reinforcement in civil engineering structures. Following a discussion of the science underpinning their use, selected case studies where FRP reinforcement has been used are presented. The use of FRP reinforcement is rapidly gaining pace and may replace the traditional steel due to its enhanced properties and cost‐effectiveness. In addition, FRP reinforcement offers an effective solution to the problem of steel durability in aggressive environments and where the magnetic or electrical properties of steel are undesirable.
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