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The building sector of the construction industry incorporates a precipitous and volatile nature with poor safety conditions being prevalent, owing to its inability to determine an appropriate trade-off between productivity and safety. This disproportionate trade-off produces production pressures, which contribute poorly to construction performance, by encouraging workers to prioritise their working productivity ahead of safety. The purpose of this study is to investigate the impacts of production pressures in the building sector and propose mitigation strategies accordingly.

A systematic review of literature was conducted, and secondary data were extracted from peer-reviewed journal papers. The data was then analysed to achieve the objectives of this study.

The main causes of production pressures are tight construction schedules, ineffective management and construction rework. Furthermore, the negative effects of production pressures are increased levels of stress in employees, reduced craftsmanship, encouraging accident-prone environments and decreasing employee’s safety behaviour. Effective mitigation strategies in relation to scheduling, leadership, communication and motivation were proposed. Finally, a causal loop diagram of production pressures in the building sector was developed.

This research will assist in creating a safer working environment within the building sector, by providing useful information regarding the severity of production pressures and suggesting mitigation strategies that can be implemented in the construction projects.

It is well-known that significant production pressures exist on many construction projects and previous studies have suggested that this pressure is a contributory factor in safety incidents on sites. While research has established that production pressures exist, less is understood about the construction practices that occur when projects are under such pressures and their repercussion for safety. The paper aims to discuss this issue.

Through an ethnographic approach on a large construction project in the UK, these practices were explored and unpacked. The lead researcher was a member of the Health and Safety department, and undertook participant observation as a main research tool for three years.

It was found that informal, covert and dangerous “piecework” strategies were adopted at the site level in direct response to scheduling demands. Construction workers were incentivised through extra finance and rest periods to finish the work quickly, which, in turn, prioritised production over safety. Unreasonable production pressures remain an unresolved problem in the construction industry and are, perhaps consequentially, being informally managed on-site.

This study improves our understanding of the complexities involved in the unresolved demands between production and safety on construction sites, which marks a step towards addressing this substantial challenge that is deeply ingrained within the industry.

The purpose of this study showcase a realistic model for estimating pressure drop at any production time in any location along the vertical flowing solid-gas well. Also to simulate the impact of solid particles on the pressure transient in gas well. The production of natural gas from the reservoir is always associated with entrained solid particle of different sizes, mainly sand particles and crystalline salts. Entrained solid transport along the gas phase has been a great concern for gas production engineer, as the detrimental consequences are often associated to desirable high operational parameters, such as rate and pressure transverse in producing well.

A variety of early models for predicting pressure transverse in gas wells were based on steady state flow equation that did not consider time factor, which results in inaccuracy at early production time. Some of the early investigators overlooked the effect of the solid on the pressure transverse phenomena in a gas well. Hence, there is a need for developing a model for estimating pressure transverse at all times in solid–gas well. This study presents an equation for pressure drop in flowing vertical well without neglecting any term in the momentum equation by the inclusion of accumulation and kinetic term.

The solution of the resulting differential equation gives functional relationship between solid–gas flow rates and pressure at any point in flowing well at any given production time. The results show improvement over previous studies, as the assumptions previously neglected were all considered.

A more realistic result that includes the initial unsteadiness phenomenon is obtained; hence, predicting pressure transient at any given production time has been established for both gas that flows along with solid particles and gas without particles. At the onset of production, the effect of all possible wellbore pressure losses is highly pronounced and decreased as the production time increases. The newly developed model, however, can be used at all depths. The effect of using the Sukkar and Cornell model is extremely adverse for the calculation of other parameters, such as flow rate, and carrying out economic analysis.

This paper aims to establish a mathematical model for water-flooding considering the impact of fluid–solid coupling to describe the process of development for a low-permeability reservoir. The numerical simulation method was used to analyze the process of injected water channeling into the interlayer.

Some typical cores including the sandstone and the mudstone were selected to test the permeability and the stress sensitivity, and some curves of the permeability varying with the stress for the cores were obtained to demonstrate the sensitivity of the formation. Based on the experimental results and the software Eclipse and Abaqus, the main injection parameters to reduce the amount of the injected water in flowing into the interlayer were simulated.

The results indicate that the permeability of the mudstone is more sensitive to the stress than sandstone. The injection rate can be as high as possible on the condition that no crack is activated or a new fracture is created in the development. For the B82 block of Daqing oilfield, the suggested pressure of the production pressure should be around 1–3MPa, this pressure must be gradually reached to get a higher efficiency of water injection and avoid damaging the casing.

This work is beneficial to ensure stable production and provide technical support to the production of low permeability reservoirs containing an interlayer.

The purpose of this paper is to present a detailed algorithm for simulating three-dimensional hydrocarbon reservoirs using the blackoil model.

The numerical algorithm uses a cell-centred structured grid finite volume method. The blackoil formulation is written in a way that an Implicit Pressure Explicit Saturation approach can be used. The flow field is obtained by solving a general gas pressure equation derived by manipulating the governing equations. All possible variations of the pressure equation coefficients are given for different reservoir conditions. Key computational details including treatment of non-linear terms, expansion of accumulation terms, transitions from under-saturated to saturated states and vice versa, high gas injection rates, evolution of gas in the oil production wells and adaptive time-stepping procedures are elaborated.

It was shown that using a proper linearization method, less computational difficulties occur especially when free gas is released with high rates. The computational performance of the proposed algorithm is assessed by solving the first SPE comparative study problem with both constant and variable bubble point conditions.

While discretization is performed and implemented for unstructured grids, the numerical results are presented only for structured grids, as expected, the accuracy of numerical results are best for structured grids. Also, the reservoir is assumed to be non-fractured.

The proposed algorithm can be efficiently used for simulating a wide range of practical problems wherever blackoil model is applicable.

A complete and detailed description of ingredients of an efficient finite volume-based algorithm for simulating blackoil flows in hydrocarbon reservoirs is presented.

The production of natural gas from the reservoir is always associated with entrained solid particle of different sizes mainly sand particles and crystalline salts. Entrained solid transport along the gas phase has been a great concern for gas production engineer, as the detrimental consequences are often associated to a desirable high operational parameters such rate and pressure transverse in producing well.

A variety of models for predicting pressure transverse in flowing gas wells have been reported in the literatures. Most of the models were based on steady state fluid flow equation that did not consider time factor which results in inaccurate at early production time. Some of the early investigators overlooked the effect of the entrained solid on the pressure transverse phenomena in a gas well. Hence, there is a need for developing a more realistic model for estimating pressure transverse at all times in flowing solid-gas vertical well.

This study presents equation for pressure drop in flowing vertical well without neglecting any term in the momentum equation by the inclusion of accumulation and kinetic term. The solution of the resulting differential equation gives functional relationship between solid-gas flow rates and pressure at any point in flowing well at any given production time.

The results show improvement over previous studies, as the assumptions previously neglected were all considered.

This chapter examines and discusses the unintended outcomes of the production bonus scheme the mine had instituted to motivate and increase the productivity of the frontline mining teams. This is crucial given that the maladministration of the bonus system could lead to a range of undesired outcomes such as deteriorating levels of trust between management and frontline workers, prioritisation of production at the expense of safety, poor work relations and ultimately low levels of organisational, employee and team performance. There are a number of organisational, management and labour factors that can render a production bonus scheme effective or ineffective. These factors influence the nature and extent of worker reactions to the bonus scheme.

This chapter examines and discusses the factors that influenced the reaction of the mining teams to the team-based production bonus scheme and the extent to which mine management fulfilled its side of the bargain in the implementation of the production bonus. The chapter highlights the manner in which the team-based bonus system influenced teams of stope workers to engage in their informal organisational practice of making plan (planisa) in order to offset the snags that jeopardised their prospects of earning the production bonus. The chapter reveals that, to a large extent, the productivity bonus generated conflict rather than cooperation at the point of production down the mine. As a result, the incentive scheme failed to live up to expectations by not eliciting the desired levels of organisational, worker and team performance at the rock-face.

This chapter examines the interaction between formal and informal organisation of work in a deep-level mining workplace. In response to organisational constraints, underground mining teams make a plan (planisa) to offset production bottlenecks which affected the daily running of the production process at the rock-face down the mine. They ‘get on and get by’ inside the pit to cope with organisational dysfunctions and management inefficiencies. The chapter highlights the limits of formalised work methods and the significance of the frontline miners’ informal work practice of making a plan (planisa) as an existing and alternative working practice that shapes their subjective orientation, agency and resilience to deep-level mining work processes and managerial initiatives. While the informal work practice of planisa has pros and cons, any managerial strategy designed to improve organisational productivity, safety and teamwork must recognise and systematically articulate the frontline miners’ work culture of planisa. This is especially important if we are to fully understand the limits of contemporary organisational strategies and workers’ orientations towards modernised work processes and managerial practices.

This paper aims to examine the interaction between formal and informal organisation of work inside the pit, with reference to the informal working or coping strategy of “making a plan” (planisa).

The research for this paper was ethnographic in nature and the participant observation was the main research technique used in the field.

The underground gold miners make a plan or engage in planisa to offset the production bottlenecks which affected their capacity to achieve their production targets and increase their bonus earnings. They “get on and get by” underground in order to cope with organisational constraints and management inefficiencies.

The paper highlights the limits of formal organisation of work and the significance of gold miners’ informal work strategy of making a plan (planisa) as an existing and alternative working practice that shapes their subjective orientation, agency and resilience to work structures and managerial strategies. Any strategy designed to improve the health, safety and productivity of underground miners must recognise, elaborate and systematically articulate the workplace culture of planisa as an existing work practice in the day‐to‐day running of the production process down the mine.

This chapter provides an extensive review of literature on the interaction between and interdependence of informal and formal working practices in various workplace settings. The aim of the chapter is to elucidate the organisational, managerial, human relations and social factors that give rise to informal work practices and strategies, on the shop-floor not only at workers and work group levels but also at supervisory and managerial levels. This chapter helps the reader to understand the informal work practice of making a plan (planisa) in a deep-level mining workplace.