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Article
Publication date: 5 March 2019

Ali Azadeh, Mahdokht Kalantari, Ghazaleh Ahmadi and Hossein Eslami

Construction materials comprise a major part of the total construction cost. Given the importance of bitumen as a fundamental material in construction projects, it is imperative…

Abstract

Purpose

Construction materials comprise a major part of the total construction cost. Given the importance of bitumen as a fundamental material in construction projects, it is imperative to have an accurate forecast of its consumption in the planning and material sourcing phases on the project. This study aims to introduce a flexible genetic algorithm-fuzzy regression approach for forecasting the future bitumen consumption.

Design/methodology/approach

In the proposed approach, the parameter tuning process is performed on all parameters of genetic algorithm (GA), and the finest coefficients with minimum errors are identified. Moreover, the fuzzy regression (FR) model is used for estimation. Analysis of variance (ANOVA) is used for selecting among GA, FR or conventional regression (CR). To show the applicability of the proposed approach, Iran’s bitumen consumption data in the period of 1991-2006 are used as a case study.

Findings

Production, import, export, road construction and price are considered as the input data used in the present study. It was concluded that, among all the forecasting methods used in this study, GA was the best method for estimating.

Practical implications

The proposed approach outperforms the conventional forecasting methods for the case of bitumen which is a fundamental economic ingredient in road construction projects. This approach is flexible, in terms of amount and uncertainty of the input data, and can be easily adapted for forecasting other materials and in different construction projects. It can have important implications for the managers and policy makers in the construction market where accurate estimation of the raw material demand is crucial.

Originality/value

This is the first in this field introducing a flexible GA-FR approach for improving bitumen consumption estimation in the construction literature. The proposed approach’s significance has two folds. Firstly, it is completely flexible. Secondly, it uses CRs as an alternative approach for estimation because of its dynamic structure.

Details

Construction Innovation , vol. 19 no. 1
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 12 March 2019

Deepa P., Meena Laad, Sangita and Rina Singh

The purpose of this paper is to study the recent work carried out in enhancing the properties of bitumen using nano-additives. Bitumen is a by-product obtained from the refining…

Abstract

Purpose

The purpose of this paper is to study the recent work carried out in enhancing the properties of bitumen using nano-additives. Bitumen is a by-product obtained from the refining process of crude oil, therefore making it a diminishing product. It has been used by mankind since ages for various applications like sealants, binders, waterproof coatings and pavement construction material. It is a black viscous substance with adhesive nature.

Design/methodology/approach

Bitumen is used as a binding material because of its ability to become liquid when heated and become solid when cooled and thus used largely in construction of roads because of its unique properties. Low softening point of bitumen leads to melting of bitumen during summer and causes rutting of roads, whereas during winter it leads to cracking as bitumen acts brittle in nature during low temperature. Increasing global demand of bitumen has created gap between demand and supply which is increasing with the passage of time. Further modern life has created very high traffic volume and heavy load which makes it essential to improve performance of bitumen.

Findings

Research studies have reported that the thermal properties of bitumen are enhanced by using thermoplastic polymers such as styrene-butadiene-styrene, polyethylene and ethylene-vinyl acetate, rubber and bio waste etc.

Originality/value

This paper reviews various types of materials which have been used to improve the properties of bitumen and explores the possibility to synthesise bitumen composite materials with nanoadditives with improved structural, mechanical and thermal properties.

Details

World Journal of Engineering, vol. 16 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 18 May 2015

Antonio Contarini and Arjen Meijer

The environmental performance of several flat roof systems with different materials and insulation thicknesses is compared using life cycle assessment (LCA), with the aim to…

Abstract

Purpose

The environmental performance of several flat roof systems with different materials and insulation thicknesses is compared using life cycle assessment (LCA), with the aim to determine the roofing materials with the highest environmental performance. The paper aims to discuss these issues.

Design/methodology/approach

The calculations were carried out for an existing apartment block with a 300 m² flat roof. Five insulation materials with three different heat resistances each, five types of waterproof layers, three covering layers, and a green roof are assessed using LCA. Foreground data including maintenance are obtained from roofing companies, and background data are taken from Ecoinvent. ReCiPe is used as impact method. Energy losses through the roof are calculated using the energy software EPA-W.

Findings

Improving the insulation from 2.5 to 5 m²K/W leads to reductions of the damage scores from about 10 to 40 per cent. Polyisocyanurate and expanded polystyrene were found to have the lowest environmental damage, although the differences are small. Regarding the other layers, PVC mechanically fixed, ethylene propylene diene monomer (EPDM) mechanically fixed, EPDM glued and PVC with gravel ballast were found to have the lowest environmental damage of the materials assessed.

Practical implications

The outcomes of this study will aid building owners and construction and maintenance companies to choose renovation options for flat roofs with the lowest impact on the environment.

Originality/value

A smart choice of materials for a roofing system, with enough consideration of other aspects such as practical applicability, can thus significantly improve the environmental performance of the roof of a building.

Details

Smart and Sustainable Built Environment, vol. 4 no. 1
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 1 November 1967

Fritz Endtinger and Hermann Weber

Aluminium and its alloys find application to an increasing extent in building construction. Thus in 1965 about 25% of the total consumption of aluminium in Switzerland was taken…

Abstract

Aluminium and its alloys find application to an increasing extent in building construction. Thus in 1965 about 25% of the total consumption of aluminium in Switzerland was taken up by building construction. The material is employed not only for the frames of windows and display windows, doors, facade claddings, etc., i.e. components of a decorative character, but also on an ever‐increasing scale for shell sections, roof structures, cable conduits and so on, i.e. for functional purposes. The versatile application of aluminium can be attributed to a number of favourable properties, not least among which is its good chemical behaviour. In this article we are especially concerned with the stability of aluminium in contact with alkaline building materials. Direct contact between unprotected aluminium and alkaline building materials, such as cement mortar, is as a rule avoided, since the material is protected on the side of the cement by a coat of lacquer or bitumen. For numerous applications, however, knowledge of the behaviour of the unprotected metal can be of advantage to the planning engineer.

Details

Anti-Corrosion Methods and Materials, vol. 14 no. 11
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 August 1979

H.M. Smith

Pipelines are important and expensive pieces of capital equipment and their owners are interested in their safe and economic operation. This requires the reliable protection of…

Abstract

Pipelines are important and expensive pieces of capital equipment and their owners are interested in their safe and economic operation. This requires the reliable protection of the pipes against corrosion by the use of external coatings and/or cathodic protection.

Details

Anti-Corrosion Methods and Materials, vol. 26 no. 8
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 10 February 2022

Lokesh Gupta and Rakesh Kumar

Natural good-quality sources of aggregates are depleting, whereas large amount of reclaimed asphalt pavement (RAP) is produced annually. Safe disposal and use of RAP in the cold…

Abstract

Purpose

Natural good-quality sources of aggregates are depleting, whereas large amount of reclaimed asphalt pavement (RAP) is produced annually. Safe disposal and use of RAP in the cold in-place recycling (CIR) using foamed bitumen could be sustainable approach where milling and mixing operations are accomplished simultaneously. This will not only help in minimizing contamination (probability) and transportation cost but also reduces the carbon footprints. Therefore, this study aims to investigate the scope of RAP utilization up to 100% and further its effect on the behavior of reclaimed asphalt foamed bituminous mix.

Design/methodology/approach

Reclaimed asphalt foamed bituminous mix (FBM) is still a new technique. The evidence of performance of 100% recycled pavement (CIR) is only anecdotal and lacks in systematic guidelines and literatures. Foam binder coating around the aggregates is also a concern. Therefore, this study is mainly emphasized to investigate the scope of RAP use in the FBM up to 100%. RAP content is varied in each trial, i.e. 70, 85, 100 and 0% (only fresh aggregates), to make the FBM. RAP use and its effect on the behavior of FBM in terms of resilient modulus, variation in resilient modulus with curing, rutting performance and the potential of resistance against the moisture damage are addressed.

Findings

Considering the laboratory studies, it can be accomplished that mechanistic properties and performance of FBM are largely influenced by RAP material and portray less susceptible characteristics against the moisture damage. FBM containing 70% RAP content exhibits maximum resilient modulus. However, use of RAP up to 100% in FBM is satisfying the minimum required specification.

Originality/value

Overall, the study may be helpful to highway professionals and could generate another possible option of 100% RAP replacing fresh aggregates in the flexible pavements.

Details

World Journal of Engineering, vol. 20 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 December 1961

The problem of premature failure of galvanized steel hot‐water tanks and, more occasionally, galvanized steel cold‐water cisterns, has attracted much attention. For several years…

Abstract

The problem of premature failure of galvanized steel hot‐water tanks and, more occasionally, galvanized steel cold‐water cisterns, has attracted much attention. For several years the B.N.F.M.R.A. have been investigating the causes of these failures and remedial measures and in the course of this work have organised fairly extensive field trials on the use of magnesium anodes for providing cathodic protection of the galvanized steel. In trials lasting about seven years at a number of sites where there has been a history of early failures of galvanized steel tanks or cisterns, it has been demonstrated that magnesium anodes provide a satisfactory answer.

Details

Anti-Corrosion Methods and Materials, vol. 8 no. 12
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 18 July 2019

Rok Cajzek and Uroš Klanšek

The purpose of this paper is cost optimization of project schedules under constrained resources and alternative production processes (APPs).

Abstract

Purpose

The purpose of this paper is cost optimization of project schedules under constrained resources and alternative production processes (APPs).

Design/methodology/approach

The model contains a cost objective function, generalized precedence relationship constraints, activity duration and start time constraints, lag/lead time constraints, execution mode (EM) constraints, project duration constraints, working time unit assignment constraints and resource constraints. The mixed-integer nonlinear programming (MINLP) superstructure of discrete solutions covers time–cost–resource options related to various EMs for project activities as well as variants for production process implementation.

Findings

The proposed model provides the exact optimal output data for project management, such as network diagrams, Gantt charts, histograms and S-curves. In contrast to classic scheduling approaches, here the optimal project structure is obtained as a model-endogenous decision. The project planner is thus enabled to achieve optimization of the production process simultaneously with resource-constrained scheduling of activities in discrete time units and at a minimum total cost.

Practical implications

A set of application examples are addressed on an actual construction project to display the advantages of proposed model.

Originality/value

The unique value this paper contributes to the body of knowledge reflects through the proposed MINLP model, which is capable of performing the exact cost optimization of production process (where presence and number of activities including their mutual relations are dealt as feasible alternatives, meaning not as fixed parameters) simultaneously with the associated resource-constrained project scheduling, whereby that is achieved within a uniform procedure.

Details

Engineering, Construction and Architectural Management, vol. 26 no. 10
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 2 October 2017

Ravindra Ojha and Prem Vrat

Manufacturing sector growth continues to be topical in the growth journey of Indian economy. The purpose of this paper is to present the modelling and analysis of the combined…

Abstract

Purpose

Manufacturing sector growth continues to be topical in the growth journey of Indian economy. The purpose of this paper is to present the modelling and analysis of the combined impact of three key driving sub-systems on the Indian manufacturing growth. It has provided relevant insights and recommendations for its sustainable growth.

Design/methodology/approach

The impact of three key driving sub-systems: quality of highway-related infrastructure, manufacturing labour productivity and circular material-consumption in the growth of manufacturing has been studied. A System Dynamics (SD) based model to understand long-term implications of the policy variables on manufacturing growth has been developed. Five scenarios have been simulated for analysis.

Findings

Seven policy variables have been identified which have a significant impact on Indian manufacturing growth. Some relevant insights from the analysis of SD based system-behaviour have been provided which would facilitate the manufacturing growth.

Research limitations/implications

The paper has addressed the dynamics of only three sub-systems in the study of manufacturing growth. The other sub-systems which also have an impact on the manufacturing growth: Good governance, education quality and technology are recommended to be studied through SD based modelling.

Practical implications

Specific recommendations for accelerating the manufacturing growth have been made in the paper which has strong practical implications for growth of Indian economy.

Social implications

Manufacturing sector continues to have a significant impact on the prosperity of India. It facilitates in enhancement of employment and the micro-economic health aspects. Therefore, there is a need to understand the dynamics of the key policy variables affecting manufacturing growth which is very relevant for the society at large.

Originality/value

An application of the SD approach to analyse long-term implication of policy variables of three sub-systems that have a significant impact in manufacturing growth and five specific recommendations to the policy makers is the value-add.

Details

Journal of Advances in Management Research, vol. 14 no. 4
Type: Research Article
ISSN: 0972-7981

Keywords

Article
Publication date: 14 April 2022

Guangyuan Wu, Haitao Zhang, Qixin Ge, Junfeng Sun and Tengjiang Yu

In order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium temperature…

Abstract

Purpose

In order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium temperature state can be deeply explored.

Design/methodology/approach

In this paper, the needle penetration test and temperature scanning test were designed for 90# and 70# bitumen as test materials, and the boundary of medium temperature zone of 90# and 70# bitumen was accurately determined by data analysis method. A mathematical model was established based on principal component analysis, and a comprehensive evaluation index was proposed to evaluate the evolution of temperature viscoelastic characteristics of road asphalt by means of standardization and rotational dimensionality reduction.

Findings

The test results show that the medium temperature zone of 90# asphalt is [−5 ± 1°C, 38 ± 1°C], and the medium temperature zone of 70# asphalt is [0 ± 1°C, 51 ± 1°C]. According to the viscoelastic response of road asphalt in the medium temperature zone, the medium temperature zone can be divided into three evolution stages: weak viscoelastic stage, viscoelastic equilibrium stage, strong viscoelastic weak stage. Analysis based on the intrinsic viscosity fillip target describing the various intrinsic viscoelastic index represents the viscoelastic properties of bitumen from different angles, and limitations inherent stick fillip for target put forward the integrated the inherent stick fillip mark information, as well as targeted and accurate evaluation of road asphalt temperature comprehensive evaluation indexes in the evolution of the viscoelastic properties of IM-T. Finally, the temperature data of asphalt pavement in several representative regions of China are compared with the determined medium temperature region, and it is proved that the research on the evolution of viscoelastic characteristics of asphalt pavement under the medium temperature condition has important practical significance.

Originality/value

The boundary of medium temperature zone of 90# and 70# base asphalt was determined, and the viscoelastic characteristic evolution of road asphalt under medium temperature state was studied deeply. Aiming at the limitation of intrinsic viscoelastic index, a comprehensive evaluation index IM-T which not only integrates the information of intrinsic viscoelastic index but also can accurately evaluate the evolution of temperature viscoelastic characteristics in road asphalt is proposed.

Details

Multidiscipline Modeling in Materials and Structures, vol. 18 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

1 – 10 of 145