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Article
Publication date: 1 January 1987

Lawrence R. Murphy and Joseph J. Hurrell

A growing number of studies have demonstrated the efficacy of worksite stress management training for reducing worker psychophysiological arousal and subjective reports of…

1666

Abstract

A growing number of studies have demonstrated the efficacy of worksite stress management training for reducing worker psychophysiological arousal and subjective reports of anxiety, depression, and somatic complaints. The role of stress management in the larger context of occupational stress reduction, however, has not been addressed. An application of stress management as one component of an organisational stressor reduction programme is described. Other components in the process which have been completed include the formation of a stress reduction committee and conduct of a stress assessment survey. Future plans include the formulation and implementation of recommendations for reducing organisational stress and repeated evaluations of their efficacy. The purpose is to depict element of the overall process and to report progress to date in this effort.

Details

Journal of Managerial Psychology, vol. 2 no. 1
Type: Research Article
ISSN: 0268-3946

Keywords

Article
Publication date: 1 November 1995

Les Worrall and Cary L. Cooper

Based on a sample of senior managers from West Midlands businesses,quantifies the level of executive stress in a regional setting.Identifies significant levels of stress generally…

1518

Abstract

Based on a sample of senior managers from West Midlands businesses, quantifies the level of executive stress in a regional setting. Identifies significant levels of stress generally but also reveals that stress is patterned across industrial sectors and by firm size. Also identifies and quantifies the impact of various “stress drivers” and measures the impact of stress‐related illness episodes across businesses.

Details

Personnel Review, vol. 24 no. 7
Type: Research Article
ISSN: 0048-3486

Keywords

Article
Publication date: 1 August 2016

Sampath S.S., Nethri Rammohan, Reema Shetty, Sawan Shetty and Chithirai Pon Selvan M.

Stainless steel is one of the most important elements in structural design and application, and due to its excellent properties, it is widely used in industries for conventional…

166

Abstract

Purpose

Stainless steel is one of the most important elements in structural design and application, and due to its excellent properties, it is widely used in industries for conventional structural engineering applications, such as thermal power plants, nuclear power plants, civil constructions, etc. (Mishra et al., 2014). A traditional tensile testing machine cannot determine the transversal stress–strain curves (Olden, 2002, 2013).

Design/methodology/approach

In the present study, identical mild steel specimen parts are welded at different intervals and then subjected to tensile loading. Welding is carried along the length of the specimen. Induced stresses are determined at the welded intervals and the stress–strain curve is obtained.

Findings

By considering the temperature of the weld at the interface, thermal stresses are determined. Brinell hardness number is determined at the interface and the base metal. Also, the change in the hardness at the heat-affected zone (HAZ) is found. Validation is carried out by comparing the results with the original stress–strain curve.

Originality/value

In the HAZ, there is a drop in the hardness number, which means that there is a change in the material property due to welding. The thermal stresses which develop at the interface can also play a very important role for property change. Results show that the stress developed due to the rise in temperature is lesser than that of normal stresses.

Details

World Journal of Engineering, vol. 13 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 8 February 2016

Melvin Eldho Shibu and Jithish K.S.

The catastrophic failures of these thick-wall cylinders are mainly due to the presence of inherent cracks in the material. The present study aims to deal with the analysis of…

Abstract

Purpose

The catastrophic failures of these thick-wall cylinders are mainly due to the presence of inherent cracks in the material. The present study aims to deal with the analysis of stress for a given range of inside pressure. The paper deals with the calculation of radial and tangential stresses for various external pressure-to-internal pressure ratios and external radius to internal radius of the thick-walled cylinder.

Design/methodology/approach

The inlet line to the combustion chamber normally has an internal diameter of 150 mm and has a thickness of 25 mm. Normal temperature of the working fluid is about 80°C and the outside temperature is kept as room temperature. The present work deals with the stress analysis of the inlet line with and without internal crack. Also the stress intensity factors are calculated to check with the fracture toughness. Analysis is done both theoretically and by FEM by using the well-known software ANSYS.

Findings

Results show that the radial stress is independent of the external radius-to-internal radius ratio, while the tangential stress increases.

Practical implications

In process industries like nuclear or chemical, etc., structures in the form of thick-walled cylinders play a vital role, as its failure can affect humans and the environment. Because of this, the design and analysis of the above cylinders are of much significance.

Originality/value

Due to constant or cyclic operating pressure of pressure vessels and its corresponding pipelines usually in the form of thick-walled cylinders, reliability of the materials and structures used is of critical importance, as its failure can be deadly and possess lethal dangers when the cylinder contains flammable, toxic or reactive working fluid. The major ruling factors for the failure are none other than stress-related defects and presence of cracks.

Details

World Journal of Engineering, vol. 13 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 11 March 2014

Jun Yasuda, Koji Takahashi and Hideki Okada

The purpose of this study is to clarify the influence of stress ratio (R) on the effects of shot peening (SP) on the fatigue limit of high-strength steel containing an artificial…

Abstract

Purpose

The purpose of this study is to clarify the influence of stress ratio (R) on the effects of shot peening (SP) on the fatigue limit of high-strength steel containing an artificial small defect.

Design/methodology/approach

SP was subjected on the specimens with a semi-circular slit with a depth of a=0.1, 0.2 and 0.3 mm. Then, bending fatigue tests were carried out under R=0.4.

Findings

The fatigue limits of specimens with a semi-circular slit were improved by SP under R=0.4. The fatigue limits of the SP specimens with a semi-circular slit under a=0.2 mm fractured outside the slit, and they had considerably high fatigue limits equal to specimens without a slit. Therefore, a semi-circular slit with a depth of under a=0.2 mm could be rendered harmless by SP under R=0.4. Compared to the results of R=0, the increasing ratios of fatigue limits under R=0.4 were lower than those under R=0. However, the size of semi-circular slit that could be rendered harmless by SP was same. In addition, it was found that whether the semi-circular slit is rendered harmless or not is decided by the relationship between the stress intensity factor range of semi-circular cracks and the threshold stress intensity factor regardless of stress ratio.

Practical implications

The proposed method can be applied to mechanical parts used in vehicles, aircraft and trains.

Originality/value

This is the first paper to investigate the fatigue limits after SP in materials containing a surface defect under positive stress ratio. In this study, the authors investigated the influence of stress ratio on the effects of SP on the fatigue limit containing a surface defects.

Details

International Journal of Structural Integrity, vol. 5 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 16 November 2012

M.A.K. Chowdhuri and Z. Xia

It is well known that stress singularity may exist at the edges of a bonded bi‐material interface due to the discontinuity of material properties. This stress singularity causes…

1522

Abstract

Purpose

It is well known that stress singularity may exist at the edges of a bonded bi‐material interface due to the discontinuity of material properties. This stress singularity causes difficulty in accurately determining the bi‐material interface bonding strength. This paper aims to present a new design of specimen geometry to eliminate the stress singularity and present an experimental procedure to more accurately determine the bonding strength of the bi‐material interface.

Design/methodology/approach

The design is based on an asymptotic analysis of the stress field near the free edge of bi‐material interface. The critical bonding angle, which delineates the singular and non‐singular stress field near the free edge, is determined.

Findings

With the new designed specimen and a special iterative calculation algorithm, the interface bonding strength envelope of an epoxy‐aluminum interface was experimentally determined.

Originality/value

This new design of specimen, experimental procedure and iterative algorithm may be applied to obtain more reasonable and accurate bonding strength data for a wide range of bi‐material interfaces.

Details

International Journal of Structural Integrity, vol. 3 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 March 2008

Wanpeng Wang, Zhufeng Yue, Yongle Hu and Junde Lin

This paper presents numerical simulation results of cylindrical steel lining‐concrete structure’s dynamic plastic response under internal intense blast loading by ANSYS/lS‐DYNA…

Abstract

This paper presents numerical simulation results of cylindrical steel lining‐concrete structure’s dynamic plastic response under internal intense blast loading by ANSYS/lS‐DYNA finite element software. The emphasis is put on the dynamic plastic deformation and three‐dimensional stress conditions of steel lining‐concrete structure. It is shown that maximal plastic deformation of steel lining‐concrete structure results from the first action of shock wave on internal surface of the structure. For the steel lining of the structure, radial stress is compressive stress, while hoop and axial stress is tension stress. For concrete of the structure, three‐dimension stress is compressive stress near the out surface of steel lining. Radial stress of concrete at intense shock wave seems to decay as an exponential function with increasing of scaled‐distance.

Details

Multidiscipline Modeling in Materials and Structures, vol. 4 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 December 2005

Nur Azlina Mohd Fahami, Nafeeza Mohd Ismail and Khalid Bin Abdul Kadir

This study seeks to investigate the effect of palm‐based phytonutrient complex (PPC) on stress‐induced gastric lesions and accompanying changes in the gastric acidity and gastrin…

Abstract

Purpose

This study seeks to investigate the effect of palm‐based phytonutrient complex (PPC) on stress‐induced gastric lesions and accompanying changes in the gastric acidity and gastrin level.

Design/methodology/approach

A total of 40 rats were divided between a control group that was given a vitamin E deficient diet and a treatment group that was given a vitamin deficient diet with oral supplementation of PPC at 60 mg/kg body weight for 28 days. At the end of the treatment period half of the number of rats were subjected to restraint‐stress for two hours for four consecutive days. Following stress exposure, blood was taken for measurement of gastrin level, after which all the rats were disposed of. The gastric acid was collected for measurement of acid concentration, while the stomachs were opened along the greater curvature and examined for lesions.

Findings

Rats exposed to stress developed hemorrhagic gastric lesions. PPC supplemented rats had fewer gastric lesions compared with their respective control group. Stress without supplementation with PPC also caused a reduction in the gastric acid concentration and the serum gastrin levels. Compared with their corresponding controls, the pre‐ and post‐values of gastric acid and serum gastrin concentration in rats with PPC supplementation remained comparable.

Originality/value

Stress is an identified risk factor for the development of gastric lesions. The current study showed that PPC was able to reduce the development of gastric lesions induced by stress and blocks the stress‐induced changes in the gastric acid concentration and gastrin level. It is possible that part of the protective effect of PPC in stress is through maintenance of the normal gastrin level, which results in the maintenance of gastrin trophic action in the gastric mucosa.

Details

Nutrition & Food Science, vol. 35 no. 6
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 1 January 1989

A.J. Geare

The widespread practice whereby great emphasis is placed on theharmful effects of stress with only token acknowledgement to thebeneficial effects is questioned. While accepting…

Abstract

The widespread practice whereby great emphasis is placed on the harmful effects of stress with only token acknowledgement to the beneficial effects is questioned. While accepting that stress may result in serious problems, it argues that stress is frequently enjoyed and sought by managers. The limitations of many current definitions are discussed and an alternative proposed, the definition of which accepts that stress can result in both stimulation and/or strain. Such an understanding is demanded.

Details

Employee Relations, vol. 11 no. 1
Type: Research Article
ISSN: 0142-5455

Keywords

Article
Publication date: 12 June 2017

Yunchun Xia

This paper aims to present the results of a study on the behaviour of a pre-stressed cable steel truss exposed to fire under fire conditions, basing on the results of a large…

Abstract

Purpose

This paper aims to present the results of a study on the behaviour of a pre-stressed cable steel truss exposed to fire under fire conditions, basing on the results of a large programme of experimental tests.

Design/methodology/approach

The research investigated the deformation and stress change on a pre-stressed steel cable, including the deflection and displacements at different joints and fire behaviour of the pre-stressed steel cable. In other words, the structural behaviours at different loaded pre-stress, the vertical loading, steel cable height, truss dimension and the final temperature were compared in case of fire.

Findings

The results showed that the strain of longitudinal chord was far larger than those of the transverse chords, the strains of lower chords were significantly larger than those of the upper chords, strain of the chord near the longitudinal centreline were also larger than those of the outside transverse chords. During heating, the displacement and strain gradually changed from linear to nonlinear with loading, and the yielded chord had also in an order those chords which were at mid-span and near to the longitudinal centreline, yielded at first.

Originality/value

Temperatures in the furnace and at several points of the pre-stressed cable steel truss, as well as deformations, deflections and the stress changes of upper chord and the bottom steel cable and the change of displacement at different joint were measured to achieve those goals and, consequently, to assess the deformation behaviours and temperature of the pre-stressed steel cable.

Details

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

Keywords

21 – 30 of over 126000