This research investigated whether 4D construction model effectively helps project participants on construction sites in detecting time-space conflicts in the schedule. Previous researchers on construction space management typically modeled space requirements for equipment and paths for material and focused primarily on static or dynamic layout planning. Some researchers regarded time-space conflicts as an essential aspect of construction space management. They demonstrated the use of 4D modules in time-space conflict analysis. Although these 4D prototypes have been successful in tackling time-space conflict analysis, they have been validated with only post-hoc analysis of construction projects. Also, various currently commercially available 4D visualization softwares do not take into account the workspace required during the construction of a component unless space is modeled as a separate component into the CAD application. Therefore, without modeling space as a component in the 3D model it is necessary to assess whether 4D visualization can be effectively used on construction sites to detect time-space conflicts in the schedule. In order to fulfill the research goal an experiment was conducted. A 4D construction model of an ongoing project was developed. Project participants were introduced to two different graphic representations of the schedule; namely, an overlay drawing - the conventional method used on site to detect conflicts and the 4D construction model. Analysis of the results compared the performance of the participants in detecting time-space conflicts in the schedule using the two methods. The experiment produced empirical evidence that a 4D construction model may be effective on construction sites in detecting time-space conflicts in the schedule.

Transportation projects often involve communication of project information between diverse parties and have been a challenge with increasing complexity. Communication, review and feedback are very important for planners, builders/developers and traffic engineers for successful project execution. Past research was successful in finding effective ways to communicate to stakeholders and improve project performance. 3D/4D CAD modeling has been one among them which offers potential benefits from planning to construction phase owing to its wide range of capabilities. However, there is no single tool to analyze traffic conditions and changing geometry during construction for reviewing and better decision-making. A methodology to use DTA models as a source for traffic information and development of traffic visualization during construction with microsimulation output is discussed in this thesis. The benefits of adding traffic information to 3D/4D CAD models and some potential areas of application are explored. Two case studies on TxDOT transportation construction projects are considered to explain the modeling and analysis for better understanding of different phases of the projects. Also, a small construction scenario was analyzed to validate the traffic data generated from DTA models for their use as an input to microsimulation models. / text

The creation of an effective construction schedule is fundamental to the successful completion of a construction project. Effectively communicating the temporal and spatial details of this schedule are vital, however current planning approaches often lead to multiple or misinterpretations of the schedule throughout the planning team. Four Dimensional Computer Aided Design (4D CAD) has emerged over the last twenty years as an effective tool during construction project planning. In recent years Building Information Modelling (BIM) has emerged as a valuable approach to construction informatics throughout the whole lifecycle of a building. Additionally, emerging trends in location-aware and wearable computing provide a future potential for untethered, contextual visualisation and data delivery away from the office. The purpose of this study was to develop a novel computer-based approach, to facilitate on-site 4D construction planning through interaction with a 3D construction model and corresponding building information data in outdoor Augmented Reality (AR). Based on a wide ranging literature review, a conceptual framework was put forward to represent software development requirements to support the sequencing of construction tasks in AR. Based on this framework, an approach was developed that represented the main processes required to plan a construction sequence using an onsite model based 4D methodology. Using this proposed approach, a prototype software tool was developed, 4DAR. The implemented tool facilitated the mapping of elements within an interactive 3D model with corresponding BIM data objects to provide an interface for two way communication with the underlying Industry Foundation Class (IFC) data model. Positioning data from RTK-GPS and an electronic compass enabled the geo-located 3D model to be registered in world coordinates and visualised using a head mounted display fitted with a ii forward facing video camera. The scheduling of construction tasks was achieved using a novel interactive technique that negated the need for a previous construction schedule to be input into the system. The resulting 4D simulation can be viewed at any time during the scheduling process, facilitating an iterative approach to project planning to be adopted. Furthermore, employing the IFC file as a central read/write repository for schedule data reduces the amount of disparate documentation and centralises the storage of schedule information, while improving communication and facilitating collaborative working practices within a project planning team. Post graduate students and construction professionals evaluated the implemented prototype tool to test its usefulness for construction planning requirements. It emerged from the evaluation sessions that the implemented tool had achieved the essential requirements highlighted in the conceptual framework and proposed approach. Furthermore, the evaluators expressed that the implemented software and proposed novel approach to construction planning had potential to assist with the planning process for both experienced and inexperienced construction planners. The following contributions to knowledge have been made by this study in the areas of 4D CAD, construction applications of augmented reality and Building Information Modelling; · 4D Construction Planning in Outdoor Augmented Reality (AR) · The development of a novel 4D planning approach through decomposition · The deployment of Industry Foundation Classes (IFC) in AR · Leveraging IFC files for centralised data management within real time planning and visualisation environment.

Currently in the field of demolition, which generates most of the waste in the construction industry, the treatment of waste largely relies on landfill or degraded recycling, which leads to significant consumption of natural resource and energy and a shortage of landfill site. In order to improve the inefficiency of demolition waste recovery, “to suggest improvements in the environmental impact of the demolition industry in UK” was set as the aim of the present research. After the identification of few opportunities for communication between demolishers and constructers in the current social system, a collaboration support system between these two stakeholders called ‘Demolition Project Mapping’ (DPM) system was suggested. In the system, the impact evaluation tool developed in the 4D-CAD software is applied to the demolition project simulation. This tool allows the users to dynamically simulate the impact of project planning which can be designed in the tool. In the pilot study, the simulation result shows the large potential to reduce the impact (e.g. 28% for the cost) by the tool application.

The use and application of 4 Dimensional Computer Aided Design (4D CAD) is growing within the construction industry. 4D approaches have been the focus of many research efforts within the last decade and several commercial tools now exist for the creation of construction simulations using 4D approaches. However, there are several key limitations to the current approaches. For example, 4D models are normally developed after the initial planning of a project has taken place using more traditional techniques such as Critical Path Method (CPM). Furthermore, mainstream methodologies for planning are based on individual facets of the construction process developed by discrete contractors or sub-contractors. Any 4D models generated from these data are often used to verify work flows and identify problems that may arise, either in terms of work methods or sequencing issues. Subsequently, it is perceived that current 4D CAD approaches provide a planning review mechanism rather than a platform for a novel integrated approach to construction planning. The work undertaken in this study seeks to address these issues through the application of a distributed virtual reality (VR) environment for collaborative 4D based construction planning. The key advances lie in catering for geographically dispersed planning by discrete construction teams. By leveraging networked 4D-VR based technologies, multidisciplinary planners, in different places, can be connected to collaboratively perform planning and create an integrated and robust construction schedule leading to a complete 4D CAD simulation. Establishing such a complex environment faces both technological and social challenges. Technological challenges arise from the integration of traditional and recent 4D approaches for construction planning with an ad hoc application platform of VR linked through networked computing. Social challenges arise from social dynamics and human behaviours when utilizing VR-based applications for collaborative work. An appropriate 4D-based planning method in a networked VR based environment is the key to gaining a technical advancement and this approach to distributed collaborative planning tends to promote computer-supported collaborative work (CSCW). Subsequently, probing suitable CSCW design and user interface/interaction (UI) design are imperative for solutions to achieve successful applicability. Based on the foregoing, this study developed a novel robust 4D planning approach for networked construction planning. The new method of interactive definition was devised through theoretical analysis of human-computer interaction (HCI) studies, a comparison of existing 4D CAD creation, and 3D model based construction planning. It was created to support not only individual planners’ work but multidisciplinary planners’ collaboration, and lead to interactive and dynamic development of a 4D simulation. From a social perspective, the method clarified and highlighted relevant CSCW design to enhance collaboration. Applying this rationale, the study specified and implemented a distributed groupware solution for collaborative 4D construction planning. Based on a developed system architecture, application mode and dataflow, as well as a real-time data exchange protocol, a prototype system entitled ‘4DX’ was implemented which provides a platform for distributed multidisciplinary planners to perform real-time collaborative 4D construction planning. The implemented toolkit targeted a semi-immersive VR platform for enhanced usability with compatibility of desktop VR. For the purpose of obtaining optimal UI design of this kind of VR solution, the research implemented a new user-centred design (UCD) framework of Taguchi-Compliant User-Centred Design (TC-UCD) by adapting and adopting the Taguchi philosophy and current UCD framework. As a result, a series of UIs of the VR-based solution for multifactor usability evaluation and optimization were developed leading to a VR-based solution with optimal UIs. The final distributed VR solution was validated in a truly geographically dispersed condition. Findings from the verification testing, the validation, and the feedback from construction professionals proved positive in addition to providing constructive suggestions to further reinforce the applicability of the approach in the future.