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Article
Publication date: 2 October 2017

Abdolhosein Haddad, Danial Rezazadeh Eidgahee and Hosein Naderpour

The purpose of this study is to introduce a relatively simple method of probabilistic analysis on the dimensions of gravity retaining walls which might lead to a more accurate…

Abstract

Purpose

The purpose of this study is to introduce a relatively simple method of probabilistic analysis on the dimensions of gravity retaining walls which might lead to a more accurate understanding of failure. Considering the wall geometries in the case of allowable stress design, the probability of wall failure is not clearly defined. The available factor of safety may or may not be sufficient for the designed structure because of the inherent uncertainties in the geotechnical parameters. Moreover, two cases of correlated and uncorrelated geotechnical variables are considered to show how they affect the results.

Design/methodology/approach

This study is based on the failure and stability of gravity retaining walls which can be stated in three different modes of sliding, overturning and the foundation-bearing capacity failure. Each of these modes of failure might occur separately or simultaneously with a corresponding probability. Monte Carlo simulation and Taylor series method as two conventional methods of probability analysis are implemented, and the results of an assumed example are calculated and compared together.

Findings

The probability analysis of the failure in each mode is calculated separately and a global failure mode is introduced as the occurrence of three modes of sliding, overturning and foundation-bearing capacity failure. Results revealed that the global mode of failure can be used along with the allowable stress design to show the probability of the worst failure condition. Considering the performance and serviceability level of the retaining structure, the global failure mode can be used. Furthermore, the correlation of geotechnical variables seems to be relatively more dominant on the probability of global failure comparing to each mode of failure.

Originality/value

The introduced terminology of global mode of failure can be used to provide more information and confidence about the design of retaining structures. The resulted graphs maintain a thorough insight to choose the right dimensions based on the required level of safety.

Details

World Journal of Engineering, vol. 14 no. 5
Type: Research Article
ISSN: 1708-5284

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: 5 July 2021

Tamir Amari and Mohamed Nabil Houhou

This paper aims to investigate single pile and pile group responses due to deep braced excavation-induced soil movement in soft clay overlying dense sand. The analysis focuses…

Abstract

Purpose

This paper aims to investigate single pile and pile group responses due to deep braced excavation-induced soil movement in soft clay overlying dense sand. The analysis focuses first on the response of vertical single pile in terms of induced bending moment, lateral deflection, induced axial force, skin resistance distribution and pile settlement. To better understand the single pile behaviour, a parametric study was carried out. To provide further insights about the response of pile group system, different pile group configurations were considered.

Design/methodology/approach

Using the explicit finite element code PLAXIS 3 D, a full three-dimensional numerical analysis is carried out to investigate pile responses when performing an adjacent deep braced excavation. The numerical model was validated based on the results of a centrifuge test. The relevance of the 3 D model is also judged by comparison with the 2 D plane strain model using the PLAXIS 2 D code.

Findings

The results obtained allowed a thorough understanding of the pile response and the soil–pile–structure interactions phenomenon. The findings reveal that the deep excavation may cause appreciable bending moments, lateral deflections and axial forces in nearby piles. The parametric study showed that the pile responses are strongly influenced by the excavation depth, relative pile location, sand density, excavation support system and pile length. It also showed that the response of a pile within a group depends on its location in relation to the other piles of the pile group, its distance from the retaining wall and the number of piles in the group.

Originality/value

Unlike previous studies which investigated the problem in homogeneous geological context (sand or clay), in this paper, the pile response was thoroughly studied in a multi-layered soil using 3 D numerical simulation. To take into account the small-strain nonlinear behaviour of the soil, the Hardening soil model with small-strain stiffness was used in this analysis. For a preliminary design, this numerical study can serve as a practical basis for similar projects.

Details

World Journal of Engineering, vol. 19 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 13 June 2020

Sahar Ghobadi and Hadi Shahir

The purpose of this paper is to study the distribution of active earth pressure in retaining walls with narrow cohesion less backfill considering arching effects.

Abstract

Purpose

The purpose of this paper is to study the distribution of active earth pressure in retaining walls with narrow cohesion less backfill considering arching effects.

Design/methodology/approach

To this end, the approach of principal stresses rotation was used to consider the arching effects.

Findings

According to the presented formulation, the active soil pressure distribution is nonlinear with zero value at the wall base. The proposed formulation implies that by increasing the frictional forces at both sides of the backfill, the arching effect is increased and so, the lateral earth pressure on the retaining wall is decreased. Also, by narrowing the backfill space, the lateral earth pressure is extremely decreased.

Originality/value

A comprehensive analytical solution for the active earth pressure of narrow backfills is presented, such that the effects of the surcharge and the characteristics of the stable back surface are considered. The magnitude and height of the application of lateral active force are also derived.

Details

Engineering Computations, vol. 38 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 25 October 2020

Mohamed Nabil Houhou, Abderahim Belounar, Tamir Amari and Abdelaziz Brouthen

This paper aims to focus on three-dimensional (3D) numerical simulation of a monitored urban underground road consisting of diaphragm walls supported by one row of temporary steel…

Abstract

Purpose

This paper aims to focus on three-dimensional (3D) numerical simulation of a monitored urban underground road consisting of diaphragm walls supported by one row of temporary steel struts and a cover slab in the central area. In addition to the lateral wall displacements, the analysis focuses on the load development in the struts and the evolution of the total stresses at the soil–wall interface, and highlights the 3D effect on the behavior of the structure.

Design/methodology/approach

Computation by back-analysis has become an important contribution to the understanding of observed phenomena. In this context, this paper investigates a full 3D numerical back-analysis of diaphragm wall deformation using the finite difference code FLAC3D.

Findings

The instrumentation allows a deep understanding of the ground response and the soil-structure interaction phenomena. It also provides an opportunity to validate numerical models. Using a soil model with simple failure criteria, the wall displacements are strongly influenced by the soil deformation modulus. The strut stiffness considerably influences the wall behavior. The geometrical effects have a significant impact on the induced wall displacements.

Originality/value

In the present study, the main soil geotechnical characteristics were deduced from laboratory and in situ tests. However, Young’s modulus of the soil has been adjusted to take account of the unloading effect. In the same context, the non-linearity of the elastic characteristics of the steel struts has been taken into account by modeling the struts using their experimental stiffness instead of their theoretical rigidity.

Details

World Journal of Engineering, vol. 18 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 March 2004

J.B. Yang

This paper presents a hybrid artificial intelligence (AI) system capable of integrating techniques of case‐based reasoning, rule induction and expert system, using them for…

Abstract

This paper presents a hybrid artificial intelligence (AI) system capable of integrating techniques of case‐based reasoning, rule induction and expert system, using them for knowledge acquisition and problem solving of selecting appropriate retaining wall systems at the project planning stage. The proposed hybrid system can eliminate the bottleneck of knowledge acquisition in developing a knowledge‐based system and improve the solution quality of the AI‐based system. Test results indicate that solutions generated by the proposed hybrid system are better than those generated by using a single technique.

Details

Construction Innovation, vol. 4 no. 1
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 1 March 1984

W.G. Curtin

Introduction The Victorian engineers built literally miles of mass brickwork retaining walls. Such walls relied on their dead weight to resist the overturning forces and tensile…

Abstract

Introduction The Victorian engineers built literally miles of mass brickwork retaining walls. Such walls relied on their dead weight to resist the overturning forces and tensile stresses caused by the retained earth, or other material. But the walls were of relatively massive thickness, under‐exploited brick‐work's compressive strength, and were structurally restricted by brickwork's low tensile strength. The advent of the more cost‐effective reinforced concrete walls saw their vitual eclipse. Reinforcing the brickwork could result in a come‐back.

Details

Structural Survey, vol. 2 no. 3
Type: Research Article
ISSN: 0263-080X

Book part
Publication date: 15 December 2016

Briana Preminger and Gili S. Drori

With this paper we aimed to explore the matter of space as a physical expression of institutional logics. Following recent discussions on the role of materiality in organizational…

Abstract

With this paper we aimed to explore the matter of space as a physical expression of institutional logics. Following recent discussions on the role of materiality in organizational discourse, this study focused on spatial dimensions of institutional logics, namely, spatialized logics. Utilizing Lefebvre’s (1991) analytic distinction among three layers of space – conceived, lived, and perceived – we described the spatial expressions of distinct logics and the spatial relations among these logics. Drawing on a qualitative case study analysis of the world-renowned site of Jerusalem’s Western Wall, we argued that logics take form in space, logics get embodied in different layers of space, and matters of discursive commensurability and leakages also have spatial expressions. To exemplify these claims we undertook a qualitative case study analysis of Jerusalem’s Western Wall. The Wall is a 500-meter-long and two-millennia-old construction. We showed that, while in material and technical terms the Wall is a singular entity, three distinct logics occupy distinct sections along the Wall, and each of these logics reinterprets the materials and technicalities in distinct ways: religious, professional, and nationalistic. These three distinct spatialized logics get embodied in the conceived space (planning and policy of the site), perceived space (comments and opinions about the site), and lived space (behavior and social interaction at the site). Overall, by interjecting notions of materiality and space into the conversation about institutional logics, we demonstrated that in the physical layout of a space, logic cohesion, and interlogic commensurability literally become a “turf war.”

Details

How Institutions Matter!
Type: Book
ISBN: 978-1-78635-429-7

Keywords

Article
Publication date: 21 May 2020

Seyyed Pouya Alavinezhad and Hadi Shahir

The purpose of this study is to present a diagram for the lateral earth pressure of c–φ soils exerted on anchored walls in presence of surcharge.

Abstract

Purpose

The purpose of this study is to present a diagram for the lateral earth pressure of c–φ soils exerted on anchored walls in presence of surcharge.

Design/methodology/approach

To this end, two-dimensional plane strain modeling of anchored wall was carried out in Plaxis software. To validate the numerical model, two excavations with different specifications were simulated and the model results were compared with the available results. Subsequently, a parametric analysis was done and based on its results, a diagram was proposed for the lateral earth pressure of c–φ soils including the surcharge effects.

Findings

The proposed diagram without the surcharge and cohesion effects is a trapezoidal with zero value at the ground surface that is linearly approaching the apparent earth pressure of sand according to Terzaghi and Peck (1967) at 0.1H (H: wall height). The surcharge and cohesion effects at the ground level is 4 Ka*q and 0, respectively, and below 0.1H, they are treated as the same way for lateral earth pressure of a retaining wall. It should be emphasized that the apparent pressure diagram for design does not resemble the real distribution of earth pressure against the wall and it is for calculating the values of the anchors loads.

Originality/value

The available diagrams to determine the earth pressure exerted on the anchored walls are related to sandy or clayey soils and do not take the presence of surcharge into account. Thus, the proposed diagram is quite original and different from the previous ones.

Details

World Journal of Engineering, vol. 17 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 June 1997

James L. Price

Addresses the standardization of the measurements and the labels for concepts commonly used in the study of work organizations. As a reference handbook and research tool, seeks to…

16010

Abstract

Addresses the standardization of the measurements and the labels for concepts commonly used in the study of work organizations. As a reference handbook and research tool, seeks to improve measurement in the study of work organizations and to facilitate the teaching of introductory courses in this subject. Focuses solely on work organizations, that is, social systems in which members work for money. Defines measurement and distinguishes four levels: nominal, ordinal, interval and ratio. Selects specific measures on the basis of quality, diversity, simplicity and availability and evaluates each measure for its validity and reliability. Employs a set of 38 concepts ‐ ranging from “absenteeism” to “turnover” as the handbook’s frame of reference. Concludes by reviewing organizational measurement over the past 30 years and recommending future measurement reseach.

Details

International Journal of Manpower, vol. 18 no. 4/5/6
Type: Research Article
ISSN: 0143-7720

Keywords

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