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Article
Publication date: 9 October 2019

Hui Chen and Donghai Liu

The purpose of this study is to develop a stochastic finite element method (FEM) to solve the calculation precision deficiency caused by spatial variability of dam compaction…

Abstract

Purpose

The purpose of this study is to develop a stochastic finite element method (FEM) to solve the calculation precision deficiency caused by spatial variability of dam compaction quality.

Design/methodology/approach

The Choleski decomposition method was applied to generate constraint random field of porosity. Large-scale laboratory triaxial tests were conducted to determine the quantitative relationship between the dam compaction quality and DuncanChang constitutive model parameters. Based on this developed relationship, the constraint random fields of the mechanical parameters were generated. The stochastic FEM could be conducted.

Findings

When the fully random field was simulated without the restriction effect of experimental data on test pits, the spatial variabilities of both displacement and stress results were all overestimated; however, when the stochastic FEM was performed disregarding the correlation between mechanical parameters, the variabilities of vertical displacement and stress results were underestimated and variation pattern for horizontal displacement also changed. In addition, the method could produce results that are closer to the actual situation.

Practical implications

Although only concrete-faced rockfill dam was tested in the numerical examples, the proposed method is applicable for arbitrary types of rockfill dams.

Originality/value

The value of this study is that the proposed method allowed for the spatial variability of constitutive model parameters and that the applicability was confirmed by the actual project.

Details

Engineering Computations, vol. 36 no. 9
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 10 January 2020

Shi Yang Pan, Jing Cheng and Tong Chun Li

The meshfree node-based smoothed point interpolation method (NS-PIM) is extended to the forward and inversion analysis of a high gravelly soil core rock-fill dam during…

Abstract

Purpose

The meshfree node-based smoothed point interpolation method (NS-PIM) is extended to the forward and inversion analysis of a high gravelly soil core rock-fill dam during construction periods.

Design/methodology/approach

As one member of the meshfree methods, the NS-PIM has the advantages of “softer” stiffness and adaptability to large deformations which is quite indispensable for the stability analysis of rock-fill dams. In this work, the present method contains a reconstruction procedure to deal with the existence or nonexistence of the construction layers. After verifying the validity of the NS-PIM method for nonlinear elastic model during construction period, the convergence features of the NS-PIM and FEM methods are further investigated with different mesh schemes. Furthermore, the NS-PIM and FEM methods are applied for the forward analysis of a high gravelly soil core rock-fill dam and the convergence features under complex stress conditions are also studied using the rock-fill dam model. Finally, the NS-PIM method is used to calculate the DuncanChang parameters of the deep overburden under the high gravelly soil core rock-fill dam based on the back-propagation neural network method.

Findings

The results show that: the NS-PIM solution for construction analysis still possesses the property of upper bound solution even under complex stress conditions and can provide comparatively more conservative results for safety evaluation. Furthermore, it can be used to evaluate the accuracy of results and mesh quality together with the FEM solution which has the property of lower bound solution; the inversion analysis in this work provides a set of material parameters for the deep overburden under high rock-fill dam during construction period and the calculated results show good agreement with the measured displacement values and it is feasible to apply the NS-PIM to the forward and inversion analysis of high rock-fill dams on deep overburden during construction periods.

Research limitations/implications

In further study, the feasibility of three-dimensional problems, elastic–plastic problems, contact problems and multipoint inversion can still be probed in the NS-PIM solution for the forward and inversion analysis of high rock-fill dams on deep overburden.

Practical implications

This paper introduced a method for the forward and inversion analysis of high rock-fill dams during construction period using the NS-PIM solution. The property of upper bound solution ensures that the NS-PIM can provide more conservative results for safety evaluation. The inversion analysis in this work provides a set of material parameters for the deep overburden under high rock-fill dam during construction periods.

Originality/value

First, the analysis from forward to inversion for high rock-fill dams during construction period using the NS-PIM solution is accomplished in this work. A procedure dealing with the existence or nonexistence of the construction layers is also developed for the construction analysis. Second, it is confirmed in this work that the NS-PIM still possesses the property of upper bound solution even under complex stress conditions (the forward analysis of high rock-fill dams during construction period). Thus, more conservative results can be provided for safety evaluation. Furthermore, it can be used to evaluate the accuracy of results and mesh quality together with the FEM solution which has the property of lower bound solution. Third, the calculated material parameters of the deep overburden in this work can be used for further studies of the high rock-fill dam.

Details

Engineering Computations, vol. 37 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 12 June 2017

Xiang Yu, Degao Zou, Xianjing Kong and Long Yu

A large, uneven settlement that is unfavourable to dam safety can occur between a concrete cut-off wall and the high-plasticity clay of earth core dam built on alluviums. This…

Abstract

Purpose

A large, uneven settlement that is unfavourable to dam safety can occur between a concrete cut-off wall and the high-plasticity clay of earth core dam built on alluviums. This issue has been often studied using the small-strain finite element (FE) method in previous research. This paper aims to research the interaction behaviour between a concrete cut-off wall and high-plasticity clay using large-deformation FE analyses.

Design/methodology/approach

The re-meshing and interpolation technique with a small-strain (RITSS) method was performed using an independently developed program and adopted for large-deformation FE analyses, and a suitable element size for the high-plasticity clay region was suggested. The layered construction process of an earth core dam built on thick alluviums was simulated using the RITSS method incorporating a hyperbolic model for soil.

Findings

The RITSS method is an effective technique for simulating the soil–structure interaction during dam construction. The RITSS analysis predicted a higher maximum principle stress of the concrete cut-off wall and higher stress levels in the high-plasticity clay region than small-strain FE analysis.

Originality/value

A practical method for large-deformation FE analysis was advised and was used for the first time to study the interaction between a concrete cut-off wall and high-plasticity clay in dam engineering. Large deformation in the high-plasticity clay was handled using the RITSS method. Moreover, the penetration process of the concrete cut-off wall into the high-plasticity clay was captured using a favourable element shape and mesh density.

Details

Engineering Computations, vol. 34 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 9 August 2023

Yi Sui, Yi Wang and Xiang Yu

The dynamic response of the nuclear power plants (NPPs) with pile foundation reinforcement have not yet been systemically investigated in detail. Thus, there is an urgent need to…

Abstract

Purpose

The dynamic response of the nuclear power plants (NPPs) with pile foundation reinforcement have not yet been systemically investigated in detail. Thus, there is an urgent need to improve evaluation methods for nonlithological foundation reinforcements, as this issue is bound to become an unavoidable task.

Design/methodology/approach

A nonlinear seismic wave input method is adopted to consider both a nonlinear viscoelastic artificial boundary and the nonlinear properties of the overburden layer soil. Subsequently, the effects of certain vital parameters on the structural response are analyzed.

Findings

A suitable range for the size of the overburden foundation is suggested. Then, when piles are used to reinforce the overburden foundation, the peak frequencies in the floor response spectra (FRS) in the horizontal direction becomes higher (38%). Finally, the Poisson ratio of the foundation soil has a significant influence on the FRS peak frequency in the vertical direction (reduce 35%–48%).

Originality/value

The quantifiable results are performed to demonstrate the seismic responses with respect to key design parameters, including foundational dimensions, the Poisson Ratio of the soil and the depth of the foundation. The results can help guide the development of seismic safety requirements for NPPs.

Details

Engineering Computations, vol. 40 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 4 November 2022

Xiang-Nan Wang, Yi-Zhao Gao, Xiang-Tao Zhang, Yu-Zhen Yu and He Lv

The stress–strain behaviors of rockfill materials in dams are significantly affected by the anisotropy and grain crushing. However, these factors are rarely considered in…

Abstract

Purpose

The stress–strain behaviors of rockfill materials in dams are significantly affected by the anisotropy and grain crushing. However, these factors are rarely considered in numerical simulations of high rockfill dams. This study intends to develop a reasonable and practical constitutive model for rockfill materials to overcome the above problems.

Design/methodology/approach

The effects of anisotropy and grain crushing are comprehensively considered by the spatial position of the reference state line. After the improved generalized plasticity model for rockfill materials (referred to as the PZR model) is developed and verified by laboratory tests, it is used with the finite element method to simulate the stress–strain behaviors of the Nuozhadu high core rockfill dam.

Findings

The simulated results agree well with the laboratory tests data and the situ monitoring data, verifying the reliability and practicability of the developed PZR model.

Originality/value

A new anisotropic state parameter is proposed to reflect the nonmonotonic variation in the strength as the major principal stress direction angle varies. This advantage is verified by the simulation of a set of conventional triaxial tests with different inclination angles of the compaction plane. 2) This is the first time that the elastoplastic model is verified by the situ monitoring data of high core rockfill dams. The numerical simulation results show that the PZR model can well reflect the stress–strain characteristics of rockfill materials in high core rockfill dams and is better than the traditional EB model.

Details

Engineering Computations, vol. 39 no. 10
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 25 October 2019

Liz McDonnell, Lesley Murray, Tamsin Hinton-Smith and Nuno Ferreira

‘Living together apart’ (LTA) is the practice of remaining in close domestic proximity following the ending of an intimate relationship. Using the conceptual framework of families…

Abstract

‘Living together apart’ (LTA) is the practice of remaining in close domestic proximity following the ending of an intimate relationship. Using the conceptual framework of families in motion, in which families are re-envisioned as in flow, responding to all kinds of disruptions, chosen and unchosen, by ‘holding on’, adapting, adjusting and redirecting, this chapter explores the family practices involved in LTA. Using collaborative autoethnography – a research process in which the authors jointly explored data from their own lives – the authors were able to develop an understanding of LTA that was attentive to everyday life and the interconnections of time and space within families. The authors found that when families are living within less normative constellations, there are fewer scripts to rely upon and the potential for non-legitimacy and anxiety increases. The data also showed how deeply families are embedded in practices that are always in relation to an experienced past and imagined future. The importance of having a family story to tell that ‘works’ socially and emotionally, as well as having a home that can spatially encompass such new flows in family lives, is crucial.

Details

Families in Motion: Ebbing and Flowing through Space and Time
Type: Book
ISBN: 978-1-78769-416-3

Keywords

Open Access
Article
Publication date: 30 June 2007

Young-Tae Chang and Paul T.W. Lee

Port competition attracted much scholarly attention in Northwest Europe during the 1980s. Following the rise of powerful economies in East Asia, particularly during the 1980s and…

Abstract

Port competition attracted much scholarly attention in Northwest Europe during the 1980s. Following the rise of powerful economies in East Asia, particularly during the 1980s and 1990s, port competition has become an important phenomenon with the top five container ports in the world being located in the region. This paper aims to overview major port competition issues and outlines and analyzes the main alternative methodologies that researchers have employed to address them, referring to 70 items, mostly papers but including a few books and reports

Details

Journal of International Logistics and Trade, vol. 5 no. 1
Type: Research Article
ISSN: 1738-2122

Keywords

Book part
Publication date: 17 June 2020

Alireza Nankali, Maria Palazzo, Mohammad Jalali, Pantea Foroudi, Nader Seyyed Amiri and Gholam Heydar Salami

This chapter aims to identify integrated marketing communication (IMC) in the context of business to business to consumer (B2B2C) and empirically test a number of hypotheses…

Abstract

This chapter aims to identify integrated marketing communication (IMC) in the context of business to business to consumer (B2B2C) and empirically test a number of hypotheses related to the selected constructs. A model of the IMC was tested in a survey conducted among stakeholders in the selected field. Professionals responsible for communication and branding activities need to evaluate the relative contributions of the IMC in the B2B2C perspective.

Book part
Publication date: 13 August 2018

Robert L. Dipboye

Abstract

Details

The Emerald Review of Industrial and Organizational Psychology
Type: Book
ISBN: 978-1-78743-786-9

Book part
Publication date: 15 July 2019

Saba S. Colakoglu, Niclas Erhardt, Stephanie Pougnet-Rozan and Carlos Martin-Rios

Creativity and innovation have been buzzwords of managerial discourse over the last few decades as they contribute to the long-term survival and competitiveness of firms. Given…

Abstract

Creativity and innovation have been buzzwords of managerial discourse over the last few decades as they contribute to the long-term survival and competitiveness of firms. Given the non-linear, causally ambiguous, and intangible nature of all innovation-related phenomena, management scholars have been trying to uncover factors that contribute to creativity and innovation from multiple lenses ranging from organizational behavior at the micro-level to strategic management at the macro-level. Along with important and insightful developments in these research streams that evolved independently from one another, human resource management (HRM) research – especially from a strategic perspective – has only recently started to contribute to a better understanding of both creativity and innovation. The goal of this chapter is to review the contributions of strategic HRM research to an improved understanding of creativity at the individual-level and innovation at the firm-level. In organizing this review, the authors rely on the open innovation funnel as a metaphor to review research on both HRM practices and HRM systems that contribute to creativity and innovation. In the last section, the authors focus on more recent developments in HRM research that focus on ambidexterity – as a way for HRM to simultaneously facilitate exploration and exploitation. This chapter concludes with a discussion of future research directions.

Details

Research in Personnel and Human Resources Management
Type: Book
ISBN: 978-1-78973-852-0

Keywords

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