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Construction firms keep minimal resources to maintain productive working capital. Hence, resources are constrained and have to be shared among multiple projects in an organization. Optimal allocation of resources is a key challenge in such situations. Several approaches and heuristics have been proposed for this task. The purpose of this paper is to compare two approaches for multi-mode resource-constrained project scheduling in a multi-project environment. These are the single-project approach (portfolio optimization) and the multi-project approach (each project is optimized individually, and then heuristic rules are used to satisfy the portfolio constraint).

A direct search algorithm called Probabilistic Global Search Lausanne is used for schedule optimization. Multiple solutions are generated that achieve different trade-offs among the three criteria, namely, time, cost and quality. Good compromise solutions among these are identified using a multi-criteria decision making method, Relaxed Restricted Pareto Version 4. The solutions obtained using the single-project and multi-project approaches are compared in order to evaluate their advantages and disadvantages. Data from two sources are used for the evaluation: modified multi-mode resource-constrained project scheduling problem data sets from the project scheduling problem library (PSPLIB) and three real case study projects in India.

Computational results prove the superiority of the single-project approach over heuristic priority rules (multi-project approach). The single-project approach identifies better solutions compared to the multi-project approach. However, the multi-project approach involves fewer optimization variables and is faster in execution.

It is feasible to adopt the single-project approach in practice; realistic resource constraints can be incorporated in a multi-objective optimization formulation; and good compromise solutions that achieve acceptable trade-offs among the conflicting objectives can be identified.

An integer programming model was developed in this research to optimize the multiple objectives in a multi-project environment considering explicit resource constraints and maximum daily costs constraints. This model was used to compare the performance of the two multi-project environment approaches. Unlike existing work in this area, the model used to predict the quality of activity execution modes is based on data collected from real construction projects.

The purpose of this paper is to develop a framework to optimize time, cost and quality in a multi-mode resource-constrained project scheduling environment.

A case study approach identified the activity execution modes in building construction projects in India to support multi-mode resource-constrained project scheduling. The data required to compute time, cost and quality of each activity are compiled from real construction projects. A binary integer-programming model has been developed to perform multi-objective optimization and identify Pareto optimal solutions. The RR-PARETO3 algorithm was used to identify the best compromise trade-off solutions. The effectiveness of the proposed framework is demonstrated through sample case study projects.

Results show that good compromise solutions are obtained through multi-objective optimization of time, cost and quality.

Case study data sets were collected only from eight building construction projects in India.

It is feasible to adopt multi-objective optimization in practical construction projects using time, cost and quality as the objectives; Pareto surfaces help to quantify relationships among time, cost and quality. It is shown that cost can be reduced by increasing the duration, and quality can be improved only by increasing the cost.

The use of different activity execution modes compiled from multiple projects in optimization is illustrated, and good compromise solutions for the multi-mode resource-constrained project scheduling problems using multi-objective optimization are identified.

Procuring best value should be one of the key objectives in public sector construction projects. Best value depends upon sound “selection” strategies which ensure that the outlined project procurement objectives, including client/user demands are met. Examples of “best value” procurement are presented to demonstrate their usefulness and acceptance in principle. Further conceptualizations of various aspects of best value and the “dominance vectors” influencing the ultimate value definitions are developed, in accordance with basic public sector procurement principles. Presents a structured best value based contractor selection framework to optimize realizable value in public sector construction projects.

A Hong Kong‐based study of factors affecting construction industry performance levels confirms that selection methodologies and decisions are critical, both at the upstream formulation of procurement and operational systems themselves as well as the downstream selection of various project participants. Needs are identified for a holistic approach to broader procurement choices that incorporate all procurement sub‐systems, an integration with synergistic operational sub‐systems and more informed and intelligent participant choices. The many interacting variables and potential information overload point to the consequential need for harnessing IT/IS (information technology/information systems) to enable smarter selections at all stages of the construction supply chain. Frameworks and sample modules of the proposed knowledge‐based decision aids are presented in the case of overall procurement system selection and contractor selection.

Rework is an endemic problem in construction projects and has been identified as being a significant factor contributing cost and schedule overruns. Causal ascription is necessary to obtain knowledge about the underlying nature of rework so that appropriate prevention mechanisms can be put in place. The paper aims to discuss these issues.

Using a supervised questionnaire survey and case-study interviews, data from 112 building and engineering projects about the sources and causes of rework in projects were obtained. A multivariate exploration was conducted to examine the underlying relationships between rework variables.

The analysis revealed that there was a significant difference between rework causes for building and civil engineering projects. The set of associations explored in the analyses will be useful to develop a generic causal model to examine the quantitative impact of rework on project performance so that appropriate prevention strategies can be identified and developed.

The limitations include: small data set (112 projects), which include 75 from building and 37 from civil engineering projects.

Meaningful insights into the rework occurrences in construction projects will pave pathways for rational mitigation and effective management measures.

To date there has been limited empirical research that has sought to determine the causal ascription of rework, particularly in Hong Kong.

The purpose of this paper is to review the normative literature in regard to public-private partnerships (PPPs) and their evaluations, and attempts to investigate whether the Performance Prism is a feasible framework for effective PPP performance measurement.

An in-depth and critical literature review is conducted in this study. Discussion concentrates on PPP features, performance measurement in PPPs, performance measurement in construction, and characteristics of the Performance Prism.

The Performance Prism exhibits a strong ability to capture the distinct features of PPP infrastructure projects and can be considered as a framework suitable for effective and efficient performance measurement.

It is essential that stakeholders have a feasible performance measurement framework to effectively measure performance as they embark on PPP infrastructure projects. This paper can be used as a theoretical base and conceptual framework capable of assisting in the design and selection of effective performance measures for PPPs.

Many governments across the world use PPPs to procure public assets owing to the scarce funds available for infrastructure development. Effective performance measurement is critical to the successful delivery of a PPP project. Conventional ex post evaluation that solely focuses on meeting budget and predetermined project duration is being widely used to measure PPPs in practice. PPPs are more complicated than traditional procurement due to their multiple stakeholder integrations and long-term processes. However, the research on effective PPP performance measurement is limited for addressing such vital issues, and this paper attempts to bridge this knowledge gap.

This paper targets the development of comprehensive approaches to prequalifying teams for Public Private Partnerships (PPPs).

Research outcomes from a study into “relationally integrated project teams” (RIPTs) were applied to necessarily longer‐term PPP scenarios. A force field model was developed to visualise the importance of stronger relational forces between the many PPP participants for “sustainable RIPTs” (SRITs). A framework was conceptualised to show linkages from relational contracting approaches, through sustainable relationships to sustainable infrastructure. This framework and a basic model for evaluating relational performance, were assessed by a panel of international PPP experts.

The results encouraged the collection of factors facilitating successful relationships to build the proposed knowledge base. Literature review and initial interviews provide examples of priorities and lessons learned in relationship building in ongoing PPPs.

Being an integrative theory‐building type exercise bringing together relational contracting, teambuilding and PPP performance research streams, this paper summarises and refers to, rather than provides details of, feeder research. Fleshing out the conceptual framework and model will next proceed beyond the initial testing and sample knowledge elements conveyed herein.

Selecting good teams is essential for successful projects, and more so for PPP projects, given their complexities and longer timeframes. Increasing reliance on PPPs for infrastructure development and asset management enhances this significance.

Synergies are derived from linking relationship‐building and sustainability thrusts in the context of PPP performance. Concepts of “sustainable relationships” and “sustainsivity” (sensitivity to sustainability issues) are introduced.