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Determining the duration for road construction projects represents a problem for construction professionals in Ghana. The purpose of this paper is to develop an artificial neural network (ANN) model for determining the duration for rural bituminous surfaced road projects.

Data for 22 completed bituminous surfaced road projects from the Department of Feeder Roads (rural road agency) were collected and analyzed using the principal component analysis (PCA) and ANN techniques. The data collected were final payment certificates which contained payment bill of quantities (BOQ) of work items executed for the selected completed road projects. The executed quantities in the BOQ were the total quantities of work items for site clearance, earthworks, in-situ concrete, reinforcement, formwork, gravel sub-base/base, bitumen, road line markings and furniture, length of road and actual durations for each of the completed projects. The PCA was first employed to reduce the data in order to identify a smaller number of variables (or significant quantities) that constitute 81.58 percent of the total variance of the collected data. The ANN was then used to develop the network using the identified significant quantities as input variables and the actual durations as output variables.

The coefficient of correlation (R) and determination (R²) as well as the mean absolute percentage error (MAPE) obtained show that construction professionals can use the developed ANN model for determining duration. The study shows that the best neural network is the multi-layer perceptron with a structure 3-38-1 based on a back propagation feed forward algorithm. The developed network produces good results with an MAPE of 17.56 percent or an average accuracy of 82.44 percent.

Apart from the fact that the sample size was small, the developed model does not incorporate the implications of other likely factors that may affect contract duration.

The outcome of this study is to help construction professionals to fix realistic contract duration for road construction projects before signing a contract. Such realistic contract duration would help reduce time overruns as well as the payment of liquidated and ascertained damages by contractors for late completion.

This paper proposes an alternative way of determining the duration for road construction projects using the total quantities of work items in a final payment BOQ. The approach is based on the PCA and ANN model of quantities of work items of completed road projects.

While a considerable amount of research has been conducted on construction disputes, disputes remain prevalent in the construction industry and have still been a crucial problem in the Turkish construction industry as well. The purpose of this paper is to explore the perceptions of different stakeholders on key factors that contribute to construction disputes by adopting a qualitative approach.

The qualitative approach adopted for the study provided gathering in-depth and rich information about the topic. To explore the phenomenon in-depth information, semi-structured interviews were conducted. A total of 38 interviews were conducted among experts and practitioners who engaged in construction disputes.

Content analysis of interview data resulted in the emergence of varying categories relevant to the problems which result in construction disputes. By grouping related themes into main categories, the analysis yielded five major ones: clarity of the contract form, errors in contract documents, payments, changes, delays and not granting extension of time.

The major limitations are having interviewees from one country and results limited to the Turkish construction industry.

The findings provide insight on the factors contributing to construction disputes as perceived by different stakeholders, which should provide guidance to determine the associated risks for dispute occurrence, make effort to mitigate disputes once they happen, take proper precautions for minimizing the effects and after all make a significant contribution in the successful accomplishment of completed construction projects.

The findings of the study contribute to a deeper understanding of the factors contributing to construction disputes through a qualitative approach which is limited in the related literature. Although the qualitative exploration only focuses on the Turkish construction industry, the study has added significantly to the body of knowledge within the subject area.

Being able to predict the likelihood of a project to overrun its cost before the contract signing phase is crucial in developing the required mitigating measures to avert it. Known parameters that permit the timely prediction of cost overrun provide the basis for such predictions. Therefore, the purpose of this paper is to develop a model for forecasting cost overruns.

Ten predictive variables known before the contract signing phase of a project are identified. Based on a survey approach, information on 321 educational projects completed are compiled. A multiple linear regression analysis is adopted for the model development.

Five variables – initial contract sum, gross floor area, number of storeys, source of funds and contractors’ financial classification are observed to influence cost overruns. The model, however, yields a fairly weak coefficient of determination with a mean absolute percentage error of 30.22 and 138 per cent, respectively.

The model developed focussed on data only educational projects sampled from three out of the ten administration regions in Ghana based on a purposive sampling approach.

Policy makers and construction managers working on public projects stand to gain tremendous assistance in formulating and strengthening their own in-house cost forecasting at the precontract phase based on “what if” analysis to generate various alternative predictions of cost overruns.

Considering the innate nature of cost overruns within the Ghanaian construction industry often resulting to project abandonment, this research presents a unique dimension for tackling cost overruns based on a predictive approach.

Time overruns are commonplace within the construction industry. These result in deception because project managers critically assess the economic and financial viability of a project before implementation. Forecasting the likelihood of time overruns will not only lead to a reconsideration on the decision to build but also help put in place the necessary control measures – exactly what this research achieved.

The paper argues that rather than depending on the critical failure factors that are unknown at the pre-contract stage to forecast the likelihood of occurrence, it will be more useful to rely on project attributes that are known before contract signing. A multiple linear regression analysis is used for the model development based on ten independent variables.

About 86.6 per cent of all the projects experienced time overruns. The mean time overrun is 106.5 per cent. Initial contract sum, initial duration, gross floor area, contractor class D2K2, competitive tendering, sole sourcing and single-storey buildings explained about 44.7 per cent of the variations within time overruns, with a mean absolute percentage error of 60.7 per cent.

The predictive accuracy of the model can, in practice, be tested after the completion of a project by comparing the actual project schedule with the planned schedule. Any disparity in the expected outputs should result in a reassessment of the significant independent variables to improve the forecasting abilities of the model.

The model is expected to be very useful at the pre-contract stage when detailed designs are unavailable. As a decision support system, it will help the practitioners and decision-makers make informed decisions while minimizing the time and resources spent to arrive at these decisions.

This research presents a unique opportunity to forecast the likelihood of time overruns within the building sector based on project attributes that are known before the contract-signing phase.

The concept of working capital management (WCM) has been a fundamental financial accounting term that has evolved in financial theory for centuries. Given that the construction industry (CI) is financially dynamic, there is an imperative need to understand its WCM practices. The call for the industry players to adhere to efficient financial management practices as a result of a huge financing gap requires consented effort. This study aims to explore the trend of practices of WCM in the CI and elicit a broader polemic dialogue about this crucial theme.

The source of information for the study was secondary mainly from referenced journals and international conference papers published on WCM relating to the CI. A three-step sample selection strategy was adopted to identify the range and scope of publications on WCM in the CI based on the systematic literature review method.

The CI cannot boost of enough empirical WCM research to gain in-depth understanding of its practical trend. The developing economies are failing to produce insightful peer-reviewed papers on WCM to assist in bridging the infrastructural financing gap through apposite strategies. Gaining appropriate knowledge of the short-term financial operations through a conceptualization of WCM practices in the CI may lead to better strategies formulated for smooth operations.

This is a pioneering paper in developing economies that have taken stock of WCM knowledge of the practical trend in the CI. Future research prospects in which WCM matters can use it as a reference point.

Delayed payments have been long standing, pressing issue in construction projects, especially in Government-funded construction projects. The root causes and the consequences of delayed payments must be identified before implementing strategies to mitigate the consequences of such delayed payments. However, these causes and consequences and the parties responsible for managing the delayed payments have not been identified so far. Therefore, the purpose of this study is to investigate the management of payment delays in Government-funded construction projects.

The study used a mixed approach comprising four case studies and a questionnaire survey. The empirical data collected from the case studies and the questionnaire survey were analysed using manual content analysis and mean rating, respectively.

The study identified the most significant causes and the most significant consequences of delayed payments that occur in Government-funded construction projects. It also revealed the strategies that clients, consultants, contractors and other parties can adopt to mitigate the adverse consequences of such delayed payments.

This study identified the most significant causes of delayed payments in Government-funded construction projects, the most significant consequences of such delayed payments and the most suitable strategies the clients, consultants and contractors can adopt to mitigate the consequences of such delayed payments. Thus, this study supports streamlining the management of payment delays in Government construction projects and identifies the roles that different parties must play in managing payment delays in Government building projects, which is an under-researched area.

A major concern for construction professionals at the rural road agency in Ghana is the problem of fixing contract duration for bridge construction projects in rural areas. The purpose of the study was to develop a tool for construction professionals to forecast duration for bridge projects.

In all, 100 questionnaires were distributed to professionals at the Department of Feeder Roads to ascertain their views on the work items in a bill of quantities (BOQ) that impact significantly on the duration of bridge construction projects. Historical data for 30 completed bridge projects were also collected from the same Department. The data collected were executed work items in BOQ and actual durations used in completing the works. The qualitative data were analysed using the relative importance index and the quantitative data, processed and analysed using both the stepwise regression method and artificial neural network (ANN) technique.

The identified predictors, namely, in-situ concrete, weight of prefabricated steel components, gravel sub-base and haulage of aggregates, used as independent variables resulted in the development of a regression model with a mean absolute percentage error (MAPE) of 25 per cent and an ANN model with a feed forward back propagation algorithm with an MAPE of 26 per cent at the validation stage. The study has shown that both regression and ANN models are appropriate for predicting the duration of a new bridge construction project.

The predictors used in the developed models are limited to work items in BOQs only of completed bridge construction projects as well as the small sample size.

The study has developed a working tool for practitioners at the agency to forecast contract duration for bridge projects prior to its commencement.

The study has quantified the relationship between the work items in BOQs and the duration of bridge construction projects using the stepwise regression method and the ANN techniques.

This paper aims to focus on developing a baseline model for time overrun.

Information on 321 completed construction projects used to assess the predictive performance of two statistical techniques, namely, multiple regression and the Bayesian approach.

The eventual results from the Bayesian Markov chain Monte Carlo model were observed to improve the predictive ability of the model compared with multiple linear regression. Besides the unique nuances peculiar with projects executed, the scope factors initial duration, gross floor area and number of storeys have been observed to be stable predictors of time overrun.

This current model contributes to improving the reliability of predicting time overruns.

A distinction must be drawn between a dismissal on the one hand, and on the other a repudiation of a contract of employment as a result of a breach of a fundamental term of that contract. When such a repudiation has been accepted by the innocent party then a termination of employment takes place. Such termination does not constitute dismissal (see London v. James Laidlaw & Sons Ltd (1974) IRLR 136 and Gannon v. J. C. Firth (1976) IRLR 415 EAT).

The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act (which has been amended by the Sex Discrimination Act 1975) provides: