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Article
Publication date: 22 August 2022

Long Liu and Songqiang Wan

To make full use of the tensile strength of near surface mounting (NSM) pasted carbon fiber reinforced plastics (CFRP) strips and further increase the flexural bearing capacity…

89

Abstract

Purpose

To make full use of the tensile strength of near surface mounting (NSM) pasted carbon fiber reinforced plastics (CFRP) strips and further increase the flexural bearing capacity and flexibility of reinforced concrete (RC) beams, a new composite reinforcement method using ultra-high performance concrete (UHPC) layer in the compression zone of RC beams is submitted based on embedding CFRP strips in the tension zone of RC beams. This paper aims to discuss the aforementioned points.

Design/methodology/approach

The experimental beam was simulated by ABAQUS, and compared with the experimental results, the validity of the finite element model was verified. On this basis, the reinforced RC beam is used as the control beam, and parameters such as the CFRP strip number, UHPC layer thickness, steel bar ratio and concrete strength are studied through the verified model. In addition, the numerical calculation results of yield strength, ultimate strength, failure deflection and flexibility are also given.

Findings

The flexural bearing capacity of RC beams supported by the new method is 132.3% higher than that of unreinforced beams, and 7.8% higher than that of RC beams supported only with CFRP strips. The deflection flexibility coefficient of the new reinforced RC beam is 8.06, which is higher than that of the unreinforced beam and the reinforced concrete beam with only CFRP strips embedded in the tension zone.

Originality/value

In this paper, a new reinforcement method is submitted, and the effects of various parameters on the ultimate bearing capacity and flexibility of reinforced RC beams are analyzed by the finite element numerical simulation. Finally, the effectiveness of the new method is verified by the analytical formula.

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 31 October 2022

Yasmeen Taleb Obaidat, Wasim Barham and Rawan Abu libdeh

The main aim of this study is to examine the behavior of reinforced concrete short columns strengthened using longitudinal near surface mounted (NSM)-carbon fiber reinforced…

Abstract

Purpose

The main aim of this study is to examine the behavior of reinforced concrete short columns strengthened using longitudinal near surface mounted (NSM)-carbon fiber reinforced polymer (CFRP) strips.

Design/methodology/approach

A full 3D-finite element (FE) model was developed using ABAQUS in order to conduct the analysis. The model is first validated based on experimental data available in the literature, and then the effect of concrete compressive strength, number of CFRP strips that are used and the spacing between them were taken in consideration for both concentric and eccentric loading cases. The parametric study specimens were divided into three groups. The first group consisted of unstrengthened columns and served as control specimens. The second group consisted of columns strengthened by longitudinal CFRP strips at two opposite column faces.

Findings

The results of this study are used to develop interaction diagrams for CFRP-strengthened short columns and to develop best-fit equations to estimate the nominal axial load and moment capacities for these strengthened columns. The results showed that the specimens that were strengthened using more longitudinal CFRP strips showed a significant increase in axial load capacity and a significant improvement in the interaction diagram, especially at large load eccentricity values. This result can be justified by the fact that longitudinal strips effectively resist the bending moment that is generated due to eccentric loading. Generally, the process of strengthening using longitudinal strips only has a reasonable effect and it can be typically considered an excellent choice considering the economic aspect when the budget of strengthening is limited.

Originality/value

This research aims at studying the performance of strengthened rectangular reinforced concrete short columns with CFRP strips using FE method, developing interaction diagrams of strengthened columns in order to investigate the effect of different parameters such as compressive strength (20, 30 and 40 MPa), number of CFRP strips (1, 2, 3 and 4) and the spacing between CFRP strips in terms of the ratio of CFRP center point distance to column outside dimension ratio (0.60, 0.70 and 0.80) on the behavior of strengthened RC columns and improving empirical formulas to predict the nominal axial load and moment capacities of strengthened RC columns. These parameters that directly affect short column load carrying capacity are presented in ACI-318 (2014).

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 22 April 2024

Hesham Mohsen Hussein Omar, Mohamed Fawzy Aly Mohamed and Said Megahed

The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper…

Abstract

Purpose

The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper studies the applicability of different CG designs and the efficiency of some design parameters.

Design/methodology/approach

After reviewing a number of different papers, two designs were selected for a number of exploratory experiments. Using design of experiments (DOE) techniques to identify important design parameters. Finally, the efficiency of the parts was investigated.

Findings

The research finds that a simpler design sacrifices some effectiveness in exchange for a remarkable decrease in production cost. Decreasing infill percentage of previous designs and 3D printing them, out of TPU, experimenting with different parameters yields functional products. Moreover, the paper identified some key parameters for further optimization attempts of such prototypes.

Research limitations/implications

The cost of conducting FFF experiments for TPU increases dramatically with product size, number of parameters studied and the number of experiments. Therefore, all three of these factors had to be kept at a minimum. Further confirmatory experiments encouraged.

Originality/value

This paper addresses an identified need to investigate applications of FFF and TPU in manufacturing functional efficient flexible mechanisms, grippers specifically. While most research focused on designing for increased performance, some research lacks discussion on design philosophy, as well as manufacturing issues. As the needs for flexible grippers vary from high-performance grippers to lower performance grippers created for specific functions/conditions, some effectiveness can be sacrificed to reduce cost, reduce complexity and improve applicability in different robotic assemblies and environments.

Details

Industrial Robot: the international journal of robotics research and application, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 7 May 2024

Xin Jiang and Chengxia Liu

The current bending test method can only test the bending performance of fabric in one direction at a time. It is not possible to directly observe the bending morphology of…

Abstract

Purpose

The current bending test method can only test the bending performance of fabric in one direction at a time. It is not possible to directly observe the bending morphology of fabrics in different directions, and it is necessary to cut samples and repeat the test several times, which takes more time. For this situation, a multidirectional visualization of the fabric bending test method is proposed, using which multiple results can be obtained at one time and the fabric bending can be visualized.

Design/methodology/approach

About 17 fabrics are tested using a self-designed device. The fabrics are cut into special triangles and multiple sets of results in three directions are obtained at once using the device. The experimental specimens are photographed from the above and the transverse elongation length, bending projection area and circumference are extracted after image processing.

Findings

The results show that the correlation coefficients of transverse elongation, bending projected area and circumference are good with the bending length measured by the cantilever method. In which, all three indicators are positively correlated with the bending length. This indicates the good feasibility of the new method.

Originality/value

This method can get the bending index of fabrics in three directions, with five samples in each direction at one time. Meanwhile, it can also visualize the flexural differences between different fabrics and directions of the same fabric. It can provide more efficient testing means for the textile testing field, and the testing efficiency is 15 times of the existing method, which has better theoretical significance and practical values.

Details

International Journal of Clothing Science and Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 28 December 2023

Elizabeth Yeager Washington and Travis Logan Seay

The authors describe an original unit plan that draws from local and national concerns for truthful history education about the history of racial violence in the United States…

Abstract

Purpose

The authors describe an original unit plan that draws from local and national concerns for truthful history education about the history of racial violence in the United States. The unit plan contextualizes one impetus for truth and reconciliation in a community with a history of anti-Black violence.

Design/methodology/approach

The participants partnered with the Equal Justice Initiative to pilot the unit in their district’s new African American History course. The unit drew on historical research and cultural memory to situate local history within a broader context of racism and violence.

Findings

The teachers identified eight goals for the unit so that students could understand racialized violence, acknowledge racism as the lived experience of many of their students, and participate in a collaborative learning environment with productive discussions. Speaking from their own experiences with racism, and creating opportunities for students to do the same, the teachers aided the community in voicing long-silenced memories.

Research limitations/implications

Besides bridging some of the gaps between local, regional, and national histories, more research is needed to further examine historical trauma and its implications for both the past and present, in order to amplify and humanize experiences of racism. Additional research is a critical step in developing more thoughtful, empathic and holistic discussions of history and racism at the local level.

Practical implications

In the wake of the recent past, the authors have learned that teaching about the history of racial violence can be enhanced and empowered by reference to relevant current events. The resurgence of racially charged language and violence over the past few years makes this goal more urgent than ever. This unit gives practical guidance to teachers who face this challenge.

Social implications

The sociopolitical reality of historical trauma and racism must be confronted, and proximity to key events is important in conveying the urgency of racial violence and the need for history education that addresses it. Teachers are making difficult decisions about their options for teaching about race, and they are understandably concerned about any perceived missteps. Nonetheless, inclusive, truthful history education is an appropriate and essential response to narratives of exclusion and silence as the authors help students to develop deliberative skills concerning difficult topics such as racial violence. Teachers and students, together, can do the crucial work of remembering.

Originality/value

The stripping away of narrative agency, identity and history can cover up stories about the stripping away of life and dignity. In the unit plan, the authors recognize truth and reconciliation—especially in the education of people who have relatively little exposure to topics of race and racism—as elemental to a restorative stance against racism.

Details

Social Studies Research and Practice, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1933-5415

Keywords

Article
Publication date: 1 December 2023

Khaled Mohamed Seddik and Marwa Atif Ali

Nowadays, textiles play a striking role in various medical applications. Compression bandages are the most essential medical fabrics that help treat venous flow and edema. This…

Abstract

Purpose

Nowadays, textiles play a striking role in various medical applications. Compression bandages are the most essential medical fabrics that help treat venous flow and edema. This study aims to investigate the characteristics of different woven compressive bandage structures produced using compact cotton and cotton/lycra.

Design/methodology/approach

Four samples were weaved by matt-plain2/2, twill2/2, stripe-stain4 and mock-leno structures. Several properties were tested that related to structural performance. Tensile strength, elastic and sub-bandage pressure are considered the main functional properties. Three different analysis tools were performed: chart-diagram, one-factor ANOVA and radar chart area.

Findings

The woven structures critically affected the performance of woven compression bandage samples as well as their classifications.

Originality/value

The woven structures critically affected the performance of woven compression bandage samples as well as their classifications.

Details

Research Journal of Textile and Apparel, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 31 May 2022

Nikolaas Vande Keere, Bie Plevoets, Peggy Winkels and Livin Mosha

The paper aims to elaborate on the potential for regeneration of Bagamoyo (Tanzania) through adaptive reuse of its heritage sites. The town was the most important harbour for…

Abstract

Purpose

The paper aims to elaborate on the potential for regeneration of Bagamoyo (Tanzania) through adaptive reuse of its heritage sites. The town was the most important harbour for ivory and slaves of the East-African mainland during the 19th and early 20th century and the colonial capital of German East-Africa between 1885 and 1890. Today, it has 85,000 inhabitants who mainly live in informal settlements while stone town closer to the coast is largely abandoned with its historical buildings in a poor state of conservation.

Design/methodology/approach

The first part of the paper describes the history and heritage of the old stone town Bagamoyo, and how it impacts its identity. Additionally, it summarises the critical reception of the town's role in the application to UNESCO World Heritage for “The Central Slave and Ivory Trade Route”. This, in order to consider the reuse of its heritage sites more as part of a layered regeneration process than of a singular narrative for preservation. The second part presents research-by-design proposals investigating the economic, social and cultural potentialities of three spatial layers: the main street, the coastal strip and the shoreline.

Findings

The identity and therefore also urban regeneration of post-colonial towns such as Bagamoyo is the result of a complex combination of different narratives rather than of a singular one.

Originality/value

Bagamoyo's heritage has been studied as a driver for international tourism linked to slavery but without successful implementation. This study proposes an alternative perspective by investigating its potential for urban regeneration in line with local needs. Developed in the context of a master studio of architectural design, it presents an innovative didactic approach. Moreover, the methodology of research-by-design can be inspirational for other historical towns.

Details

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

Keywords

Open Access
Article
Publication date: 8 April 2024

Anita Meena

This paper aims to examine and compare the export performance and competitiveness of Indian and Chinese textile and clothing industry in post-multifibre arrangement (MFA) era.

Abstract

Purpose

This paper aims to examine and compare the export performance and competitiveness of Indian and Chinese textile and clothing industry in post-multifibre arrangement (MFA) era.

Design/methodology/approach

Balassa’s revealed comparative advantage Index is used to assess the competitiveness of Indian and Chinese textile and clothing exports.

Findings

The results indicate that China’s textiles and garments sector holds a greater proportion of the global market compared with India. India has a robust comparative advantage in silk, carpets and cotton post-MFA. Vegetable textile fibers, paper yarn and woven fabrics of paper yarn are also competitive. China had a strong comparative advantage in silk and fabrics; special woven fabrics, tafted textile fabrics, lace, tapestries, trimmings and embroidery in 2005. China also recorded comparative advantage in silk, man-made filaments: strip and the like of man-made textile materials, fabrics; special woven fabrics, tafted textile fabrics, lace, tapestries, trimmings and embroidery and fabrics; knitted or crocheted in 2021.

Research limitations/implications

This study’s results and recommendations could assist the Indian and Chinese Governments develop policies to upgrade their garment industries.

Originality/value

Though vast literature reviews are available for textile and apparel export performance in India and China separately, there are few studies on comparisons. This study is a significant attempt to evaluate India and China’s competitiveness in the global market.

Details

Vilakshan - XIMB Journal of Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0973-1954

Keywords

Article
Publication date: 11 January 2024

Ahmed Ashteyat, Ala Taleb Obaidat, Yasmeen Taleb Obeidat and Ahmad Bani Awwad

The paper aims to introduces an experimental work to investigate the torsional behavior of reinforced concrete (RC) beams strengthened by near-surface mounted (NSM) carbon…

23

Abstract

Purpose

The paper aims to introduces an experimental work to investigate the torsional behavior of reinforced concrete (RC) beams strengthened by near-surface mounted (NSM) carbon fiber-reinforced polymer (CFRP) ropes.

Design/methodology/approach

In this research, nine rectangular RC beams of 250 mm × 300 mm cross-section and 1,600 mm in length were constructed and tested considering the studied parameters. These parameters include the length of the CFRP rope, the orientation of the CFRP rope, the arrangement of longitudinal and the scheme of NSM-CFRP ropes.

Findings

In comparison to control specimens, the results demonstrate a considerable improvement in the torsional response of RC beams strengthened with the CFRP rope. Additionally, specimens strengthened with 90° vertical ropes increase torsional moment capacity more efficiently than specimens strengthened with 45° inclined ropes since the stress concentration leads to premature debonding of the CFRP rope. Whereas RC beams' ability to withstand torsional moments is reduced as the distance between reinforcing CFRP ropes is increased. According to test results, adding CFRP ropes to RC beams' bottoms had a slightly positive impact on torsional response.

Originality/value

This paper fulfills an identified need to study how the using of the CFRP rope is effective in strengthening RC beam subjected to torsion moment.

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 7 May 2024

Fang Haifeng, Jun Zhang, Hanlin Sun and Lihua Cai

As a new type of spinning machine, the jet spinning machine absorbs the carding system of the rotating cup spinning series and the nozzle part of the jet spinning. This paper aims…

Abstract

Purpose

As a new type of spinning machine, the jet spinning machine absorbs the carding system of the rotating cup spinning series and the nozzle part of the jet spinning. This paper aims to intends to introduce the double carding structure currently studied by the rotating cup spinning into the jet spinning machine, and analyze the influence of the nozzle characteristic number on the flow field in the double carding structure to verify the advantages of the double carding structure.

Design/methodology/approach

The simulation is used to evaluate the performance of single/double split jet spinning and nozzle feature number, verify the technical advantages of double split jet spinning and evaluate the influence of nozzle feature number on flow field. The influence of the nozzle characteristic number on the flow pattern in the four models is compared. The advantages and disadvantages of a conventional single comb and a double comb with a bypass channel on the longer side of the transport channel as an additional air supply channel are also evaluated.

Findings

At present, the double comb technology of rotary cup spinning is being studied at home and abroad to improve the spinning quality and improve the difficult problem of mixed yarn with large difference in processing fiber properties. At present, the jet spinning machine combines the advantages of rotary cup spinning and jet spinning, absorbing the comb system of rotary cup spinning series and the nozzle part of jet spinning. Therefore, it is found that the introduction of the double-split structure into the wool jet spinning has research value to improve the spinning quality.

Originality/value

The purpose of this paper is to refer to the previous research on the double comb structure in rotary spinning, and to apply the double comb structure in the new jet spinning machine to improve the spinning quality. The simulation is used to evaluate the performance of single/double split jet spinning and nozzle feature number, verify the technical advantages of double split jet spinning and evaluate the influence of nozzle feature number on flow field.

Details

International Journal of Clothing Science and Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0955-6222

Keywords

1 – 10 of 218