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Article
Publication date: 31 August 2021

Kexin Zhang, Tianyu Qi, Dachao Li, Xingwei Xue and Zhimin Zhu

The paper aims to investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening, and…

Abstract

Purpose

The paper aims to investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening, and health monitoring after reinforcement were carried out. The results of concrete strain and deflection show that the flexural strength and stiffness of the strengthened beam are improved.

Design/methodology/approach

This paper describes prestressed steel strand as a way to strengthen a 25-year-old continuous rigid frame bridge. High strength, low relaxation steel strand with high tensile strain and good corrosion resistance were used in this reinforcement. The construction process for strengthening with prestressed steel strand and steel plate was described. Ultimate bearing capacity of the bridge after strengthening was discussed based on finite element model.

Findings

The cumulative upward deflection of the second span the third span was 39.7 mm, which is basically consistent with the theoretical value, and the measured value is smaller than the theoretical value. The deflection value of the second span during data acquisition was −20 mm–10 mm, which does not exceed the maximum deflection value of live load, and the deflection of the bridge is in a safe state during normal use. Thus, this strengthened way with prestressed steel wire rope is feasible and effective.

Originality/value

This paper describes prestressed steel strand as a way to strengthen a 25-year-old continuous rigid frame bridge. To investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening and health monitoring after reinforcement were carried out.

Details

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

Keywords

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Article
Publication date: 17 June 2021

Kexin Zhang, Qi Tianyu, Li Dachao, Xue Xingwei, Fayue Wu and Xinfeng Liu

In order to understand the status of the bridge reinforcement process, the construction process monitoring of the reinforced bridge is carried out. The T-beam bridge was…

Abstract

Purpose

In order to understand the status of the bridge reinforcement process, the construction process monitoring of the reinforced bridge is carried out. The T-beam bridge was tested using the truck loading test. The displacements and concrete strains of the bridge at mid-span were measured during the test.

Design/methodology/approach

This paper describes an innovative technique, external prestressing, used to strengthen a 36-year-old prestressed T-beam bridge. This paper introduces the construction process of the prestressed reinforcement method, and makes a theoretical analysis of the reinforced bridge through the establishment of the reinforcement model.

Findings

This study showed that the structural capacity and performance of the bridge were enhanced with externally prestressed steel strand strengthening.

Originality/value

The innovative reinforcement method of prestressed T-shaped bridge is put forward, which has guiding significance for similar bridge reinforcement and maintenance.

Details

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

Keywords

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Article
Publication date: 9 August 2018

Bo Da, Hongfa Yu, Haiyan Ma and Zhangyu Wu

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand…

Abstract

Purpose

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand, seawater and cement can be widely used for the construction of ports, levees, airports and roads to achieve practical engineering values. However, the naturally porous coral structure and abundant Cl in the seawater and coral lead to extremely severe reinforcement corrosion for CASC. It is well known that Cl is the main cause of reinforcement corrosion in the marine environment. Therefore, it is necessary to research the reinforcement corrosion of CASC in the marine environment.

Design/methodology/approach

In this study, linear polarization resistance was adopted to test the linear polarization curves of reinforcement in CASC with different exposure times. Ecorr, Rp, Icorr and Vcorr were calculated according to the weak electrochemical polarization theory and Stern–Geary formula. The effects of concrete cover thickness, exposure time, reinforcement types and inhibitor on reinforcement corrosion in CASC were analysed. The reinforcement corrosion degradation rule was determined, which provided theoretical support for the durability improvement, security assessment, service life prediction and service quality control of CASC structures in marine islands and reef engineering.

Findings

The corrosion resistance was enhanced with increased concrete cover thickness, and the concrete cover thickness for organic new coated steel should be at least 5.5 cm to reduce the reinforcement corrosion risks in CASC structures. The corrosion resistance of different types of reinforcements followed the rule: 2205 duplex stainless steel > 316 stainless steel > organic new coated steel > zinc-chromium coated steel > common steel. In the early exposure stage, the anti-corrosion effectiveness of the calcium nitrate inhibitor (CN) was superior to that for the amino alcohol inhibitor (AA). With the extension of exposure time, the decreasing rate of anticorrosion effectiveness of CN was higher than that of AA.

Originality/value

Reinforcement corrosion of CASC in a marine environment was studied. Concrete cover thickness, exposure time, reinforcement type and inhibitor influenced the reinforcement corrosion were investigated. New technique of reinforcement anti-corrosion in marine engineering was proposed. Possible applications of CASC in marine engineering structures were suggested.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 1 May 2002

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…

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.

Details

Structural Survey, vol. 20 no. 2
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 12 February 2018

Sijo M.T., Jayadevan K.R. and Sheeja Janardhanan

Stir casting is a promising technique used for the manufacture of Al-SiC metal matrix composites. The clustering of reinforcement particles is a serious concern in this…

Abstract

Purpose

Stir casting is a promising technique used for the manufacture of Al-SiC metal matrix composites. The clustering of reinforcement particles is a serious concern in this production method. In this work, mushy-state solidification characteristics in stir casting are numerically simulated using computational fluid dynamics techniques to study the clustering of reinforcement particles.

Design/methodology/approach

Effects of process parameters on the distribution of particles are examined by varying stirrer speed, volume fraction of reinforcement, number of blades on stirrer and diameter ratio (ratio of crucible diameter to stirrer diameter). Further, investigation of characteristics of cooling curves during solidification process is carried out. Volume of fluid method in conjunction with a solidification model is used to simulate the multi-phase fluid flow during the mushy-state solidification. Solidification patterns thus obtained clearly indicate a strong influence of process parameters on the distribution of reinforcement particles and solidification time.

Findings

From the simulation study, it is observed that increase in stirrer speed from 50 to 150 rad/s promotes faster solidification rate. But, beyond 100 rad/s, stirrer speed limit, clustering of reinforcement particles is observed. The clustering of reinforcement particles is seen when volume fraction of reinforcement is increased beyond 10 per cent. When number of blades on stirrer are increased from three to five, an increase in solidification rate is observed, and an uneven distribution of reinforcement particles are observed for five-blade geometry. It is also seen from the simulation study that a four-blade stirrer gives a better distribution of reinforcement in the molten metal. Decrease in diameter ratio from 2.5 to 1.5 promotes faster solidification rate.

Originality/value

There is 90 per cent closeness in results for simulation study and the published experimental results.

Details

World Journal of Engineering, vol. 15 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

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Article
Publication date: 1 September 1995

Gordon R. Foxall

Methodological pluralism in consumer research is usually confinedto post‐positivist interpretive approaches. Argues, however, that apositivistic stance, radical…

Abstract

Methodological pluralism in consumer research is usually confined to post‐positivist interpretive approaches. Argues, however, that a positivistic stance, radical behaviourism, can enrich epistemological debate among researchers with the recognition of radical behaviourism′s ultimate reliance on interpretation as well as science. Although radical behaviourist explanation was initially founded on Machian positivism, its account of complex social behaviours such as purchase and consumption is necessarily interpretive, inviting comparison with the hermeneutical approaches currently emerging in consumer research. Radical behaviourist interpretation attributes meaning to behaviour by identifying its environmental determinants, especially the learning history of the individual in relation to the consequences similar prior behaviour has effected. The nature of such interpretation is demonstrated for purchase and consumption responses by means of a critique of radical behaviourism as applied to complex human activity. In the process, develops and applies a framework for radical behaviourist interpretation of purchase and consumption to four operant equifinality classes of consumer behaviour: accomplishment, pleasure, accumulation and maintenance. Some epistemological implications of this framework, the behavioural perspective model (BPM) of purchase and consumption, are discussed in the context of the relativity and incommensurability of research paradigms. Finally, evaluates the interpretive approach, particularly in terms of its relevance to the nature and understanding of managerial marketing.

Details

European Journal of Marketing, vol. 29 no. 9
Type: Research Article
ISSN: 0309-0566

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Article
Publication date: 6 June 2016

Guang Chen, Li Liu, Vadim V. Silberschmidt, Y.C. Chan, Changqing Liu and Fengshun Wu

This paper aims to systematically study the effect of reinforcement type, processing methods and reflow cycle on actual retained ratio of foreign reinforcement added in…

Abstract

Purpose

This paper aims to systematically study the effect of reinforcement type, processing methods and reflow cycle on actual retained ratio of foreign reinforcement added in solder joints.

Design/methodology/approach

Two kinds of composite solders based on SAC305 (wt.%) alloys with reinforcements of 1 wt.% Ni and 1 wt.% TiC nano-particles were produced using powder metallurgy and mechanical blending method. The morphology of prepared composite solder powder and solder pastes was examined; retained ratios of reinforcement (RRoR) added in solder joints after different reflow cycles were analysed quantitatively using an Inductively Coupled Plasma optical system (ICP-OES Varian-720). The existence forms of reinforcement added in solder alloys during different processing stages were studied using scanning electron microscope, X-ray diffractometry and energy dispersive spectrometry.

Findings

The obtained experimental results indicated that the RRoR in composite solder joints decreased with the increase in the number of reflow cycles, but a loss ratio diminished gradually. It was also found that the RRoR which could react with the solder alloy were higher than that of the one that are unable to react with the solder. In addition, compared with mechanical blending, the RRoRs in the composite solders prepared using power metallurgy were relatively pronounced.

Originality/value

Present study offer a preliminary understanding on actual content and existence form of reinforcement added in a reflowed solder joint, which would also provide practical implications for choosing reinforcement and adjusting processing parameters in the manufacture of composite solders.

Details

Soldering & Surface Mount Technology, vol. 28 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 January 2008

Elena V. Chepelyuk, Valeriy V. Choogin, David Hui and Yuri M. Strzhemechny

This paper describes a new approach for the design of multilayer reinforcements of textile composite materials and products. We offer an alternative to multilayer complex…

Abstract

This paper describes a new approach for the design of multilayer reinforcements of textile composite materials and products. We offer an alternative to multilayer complex fabrics for which the laminates of the composite reinforcement material consist of orthogonal woven fabrics with an original variable structure when each fabric layer is composed of alternating one‐ply (one warp and one weft) and one and‐ a‐half‐ply (one warp and two wefts) sections. Combination of these sections produces a “gearing” effect, preventing the delamination of textile composites in the process of their exploitation. An important aspect of the proposed method is a possibility to design woven fabrics in concurrence with the dimensions of the composite product and conditions of its exploitation; this leads to a substantial improvement of many properties of such composite product.

Details

Multidiscipline Modeling in Materials and Structures, vol. 4 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

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Article
Publication date: 6 December 2018

Jinliang Liu, Yanmin Jia, Guanhua Zhang and Jiawei Wang

The calculation of the crack width is necessary for the design of prestressed concrete (PC) members. The purpose of this paper is to develop a numerical model based on the…

Abstract

Purpose

The calculation of the crack width is necessary for the design of prestressed concrete (PC) members. The purpose of this paper is to develop a numerical model based on the bond-slip theory to calculate the crack width in PC beams.

Design/methodology/approach

Stress calculation method for common reinforcement after beam crack has occurred depends on the difference in the bonding performance between prestressed reinforcement and common reinforcement. A numerical calculation model for determining the crack width in PC beams is developed based on the bond-slip theory, and verified using experimental data. The calculation values obtained by the proposed numerical model and code formulas are compared, and the applicability of the numerical model is evaluated.

Findings

The theoretical analysis and experimental results verified that the crack width of PC members calculated based on the bond-slip theory in this study is reasonable. Furthermore, the stress calculation method for the common reinforcement is verified. Compared with the model calculation results obtained in this study, the results obtained from code formulas are more conservative.

Originality/value

The numerical calculation model for crack width proposed in this study can be used by engineers as a reference for calculating the crack width in PC beams to ensure the durability of the PC member.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 2
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 February 1991

Maurice F. Villere and Sandra S. Hartman

A “process” theory of motivation is explored, namelyreinforcement theory. Reinforcement theory is definedand the four primary strategies for implementing it – positive…

Abstract

A “process” theory of motivation is explored, namely reinforcement theory. Reinforcement theory is defined and the four primary strategies for implementing it – positive reinforcement, negative reinforcement, punishment and extinction – are described. The advantages and disadvantages of each strategy and the ways of scheduling these are outlined, together with a discussion of current research and practical implications of the theory.

Details

Leadership & Organization Development Journal, vol. 12 no. 2
Type: Research Article
ISSN: 0143-7739

Keywords

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