EXPLORING 4D AND 5D ANALYSIS IN BIM ENVIRONMENT FOR INFRASTRUCTURES: A CASE STUDY

: Building Information Modelling (BIM) has emerged as a focal point in the construction industry, garnering substantial attention due to its capacity to elevate product quality, facilitate accurate quantity determination, and enhance scheduling efficiency. The inherent complexity of construction projects necessitates the integration of BIM models endowed with automation functionalities for schedules and cost estimation. This integration ensures that updates seamlessly occur throughout the construction process, thereby mitigating project uncertainties and reducing overall costs. While the potential benefits of BIM are recognized, a substantial challenge persists in the Architecture, Engineering, and Construction (AEC) field defining workflows for the automated generation of optimized 4D/5D BIM simulation and analysis. The effective utilization of BIM as a transformative tool requires addressing this challenge to unlock its full potential in project management. BIM serves as a pivotal conduit for project data, providing a structured approach to elevate overall product quality, streamline processes, and minimize contingencies and costs associated with construction projects. Consequently, the successful implementation of BIM with automated 4D/5D simulation and analysis stands as a critical milestone in advancing the capabilities of the AEC industry, ensuring greater efficiency, accuracy, and cost-effectiveness in construction projects. According to these aspects, the time-cost analysis (4D/5D) of a project for the North-South railway station in Riyadh, designed by Architect Engineer Dia Hilal, was investigated.


INTRODUCTION
Building Information Modelling (BIM) plays a pivotal role in reshaping the conventional approach of the construction industry, transitioning from two-dimensional (2D) drawing information systems to three-dimensional (3D) object information systems.This paradigm shift transforms the documentation methodology in building design and construction, replacing manual, humanreadable practices with digital descriptions of building elements seamlessly integrated with time and cost, which are computerreadable(Arjun R. Pandey and Farzad Shahbodaghlou, 2016;Kelly et al., 2013;Mihindu and Arayici, 2008;Vacanas et al., 2016).This evolution is encapsulated in the concept of ndimensional (n-D) modelling, where diverse informational "dimensions" are merged into a comprehensive digital building model (Kagioglou, 2003).
The BIM framework, developed to delineate deliverables for Architecture, Engineering, and Construction (AEC) stakeholders, aims to achieve Integrated Project Delivery (IPD) (Akinci et al., 2002).Notably, time, a non-material but crucial element in construction projects, is presented through various perspectives, including time-space conflicts and construction schedule visualization (Chau et al., 2004;Heesom and Mahdjoubi, 2004).The incorporation of time into project assessment is exemplified by 4D Computer Aided Design (CAD), forming the foundation for 4D BIM and construction progress measurement (Kim et al., 2013).
In the realm of cost estimation, accuracy during the early stages of construction projects is widely acknowledged.Historically, cost estimation relied on user experience due to the absence of comprehensive information in the early project phases (Kaming et al., 1997).The advent of 5D BIM bridges this information gap, offering improved project financing and cash flow control.The integration framework of cost and schedule, evolving rapidly, shapes management systems and repetitive construction processes (Hegazy, 2022;Trost and Oberlender, 2003).
The isolated presentation of construction project data, such as time and cost, often lacks meaningful insights.The integration provided by 5D BIM, incorporating building information (3D), time (4D), and cost (5D), aligns with this framework, transforming isolated data into intelligent information with diverse applications (Forgues et al., 2012;Liu et al., 2014).Multi-disciplinary performance models of 5D BIM, utilized through Virtual Design and Construction (VDC), enhance information sharing, comparison, and project integration among stakeholders (Lu et al., 2018;Venturini et al., 2018).VDC ensures consistency and accuracy checks for various dimensions of information, offering graphical coordination of design, operation, and construction.Employing BIM software, this process combines 3D building components, 4D time scheduling, and 5D cost estimation, presenting a comprehensive and intuitive approach to project management (Fischer et al., 2004;Kunz andFischer, 2020, 2012).
An efficient control technique should incorporate a systematic recording method that encompasses substantial information from various sections of the project.Therefore, the development of integrated modules for cost assessment and control is essential to advance the field of building control (Hardin, 2009).This integrated approach facilitates informed decision-making and proactive measures, addressing cost-related challenges throughout the entire construction process (Solnosky, 2017;Solnosky and Luth, 2015).
In this study, following the 3D parametric modelling, a time-cost analysis (4D/5D) of a project for the North-South Riyadh railway station designed by Architect Engineer Dia Hilal was investigated.Operating as a crucial element in the Riyadh railway network, the station exemplifies a meticulous application of design principles to optimize both functionality and spatial efficiency.Architect Hilal's design strategy for the North-South Riyadh Railway Station underscores a focus on a rationalized layout, enhancing passenger flow and operational efficiency without compromising a cohesive aesthetic.

METHODOLOGY
Cost estimation involves forecasting the probable costs of a project with defined future scope, position, and completion point.The accuracy of estimates, crucial for business decisions and budget definition, is directly linked to the precision of the project scope.Reliable cost analysis relies on the accuracy of quantitative metric computation, construction methods, and physical project parameters.The Building Information Modeling (BIM) Level of Development (LOD) reflects the accuracy of information, ranging from LOD 100 to 500.Throughout different phases of the project life cycle, LOD influences model characteristics for accurate cost estimation.Initial phases (LOD 200) allow preliminary budget estimates, while the final design (LOD 300) provides more precise estimates.In the bidding phase, accuracy depends on the procurement process, with design-build projects requiring LOD 350 or higher.BIM expedites quantitative computations, facilitating cost analysis and providing real-time design and cost exploration.Owners benefit from illustrated design ideas and detailed building data, reducing long-term operational and maintenance expenses.The BIM model, reaching LOD 500, ensures quality, subcontractor interfacing, project commissioning, and continuous operation and maintenance (Venturini et al., 2018).The integration of the 4D BIM dimension links project plans with 3D model components, facilitating the comparison of different proposal plans.This visual representation of work sequences and activity durations offers various advantages: i) identification of issues not apparent in traditional schedules; ii) the ability to run scenarios to assess execution feasibility and find optimal solutions; iii) 3D visualization of impact after updating the Gantt chart.functionality becomes a productive solution for project teams to explore and identify the optimal design layout.In summary, the combined use of 4D and 5D technologies enhances (Abdel-Hamid & Abdelhaleem, 2023) project planning, visualization, and cost analysis, providing a comprehensive set of tools for efficient decision-making throughout the construction process.

CASE STUDY
The case study on the use of BIM in the Revit® software for the design of the North-South railway station in Riyadh highlights the potential benefits of adopting this technology in the infrastructure sector.The use of BIM in Revit has improved project efficiency, reduced errors, and facilitated coordination among various disciplines involved in station design.The success of implementing BIM in Revit underscores the importance of using software with advanced features for seamless BIM integration (Figure 1) (Carneiro et al., 2019;Inzerillo et al., 2023bInzerillo et al., , 2023a)).
The case study has reached the maximum Level of Detail (LOD), following a path independent of other elements in the BIM.The research aims to create a BIM model that evolves from a 3D model to 4D and 5D.The management of work phases can be carried out directly in Autodesk Navisworks®, but it is more convenient to parameterize the phases in Revit during the design to simplify the selection of elements (Figure 3).The creation of work phases in Revit already allows for a 4D management of the model, with the possibility of extrapolating temporal information of the elements through the creation of schedules.Each phase generated comprises a designated selection element with assigned time parameters in Navisworks.The Revit model needs meticulous creation to accommodate temporal construction, with the 4D approach initiating during the design phase.
In the initial modelling stage of the railway station in Revit, the process initiates by defining the construction area, establishing boundaries and parameters to guide subsequent development phases.Transitioning to the construction phase, the model undergoes a site division process, delineating distinct areas and integrating pertinent structures.The subsequent excavation phase forms the foundation of the station, identifying excavation routes and equipment and incorporating them into the model for a comprehensive representation.Progressing to foundation work, the groundwork is laid for the structural elements supporting the station.As the model evolves, construction advances to the multistory structure, capturing the distinctive features of each floor (Figure 4).Ultimately, a comprehensive representation of the railway station is crafted, seamlessly integrating all elements and intricate details to faithfully mirror the finalized infrastructure (Figure 5).Within a BIM model, elevated levels of detail concerning construction logistics were achievable.The identification of spaces and pathways was carefully assessed by considering the actual footprint of installations, machinery, and equipment within the model (see Figure 6).Precise integration of facilities, equipment, and machinery at each construction phase in the BIM model also enabled the generation of comprehensive schedules and quantities through the Revit software (Figure 7).By creating these schedules, a cost computation for all model elements, including construction equipment, has been effortlessly obtained within Revit.The computation process involved incorporating the cost parameter and manually inputting the cost value for each element to be assessed.Utilizing this approach for cost extrapolation proved beneficial in the initial stages of economic computation and served as a fundamental reference in the development of bill of quantities for the project.The simplification of element identification in the estimate was enhanced through the creation of schedules in Revit, offering a visual reference to each element within the model (Figure 8).The development of schedules not only facilitated tracking cost progression directly in the software but also allowed for the filtering of costs based on designated construction phase parameters established for the model.This modeling approach fostered connections between individual elements and their corresponding materials, streamlining construction projects and elevating estimate accuracy through intelligent data linkages.The Revit software was employed to create a model depicting the MEP (Mechanical, Electrical, Plumbing) manufacturing design, with the aim of sharing it with construction detail drafters.Utilizing the architectural and structural building models already in place, the mechanical ventilation system for Basement 3 of the station was meticulously developed.This approach enabled the early identification of notable challenges related to interferences between the ventilation system and other components during the design phase.Modelling the ventilation mechanical system in Revit facilitated the seamless integration of all essential components necessary for the system's implementation (Figure 10).Concerning the systems, it was also possible to generate quantity schedules directly, delineating the costs associated with different components (see Figure 11).These schedules allowed for the extraction of cost values for the system components by inputting pertinent information into the cost parameter.

4D Outputs
The implementation of 4D analysis using Navisworks® involves a comprehensive approach that extends beyond conventional project management.The process commenced with the development of a 3D model in Revit, incorporating diverse project elements and speculating on their respective temporal sequences.To streamline element selection in Navisworks, relevant shared parameters of a textual nature were established in Revit.These parameters, linked to the various elements within the 3D model, facilitated the creation of selection filters in Navisworks for associating the temporal parameters of different activities (Figure 12).The optimization of assigning shared parameters to the various model components was achieved through the prior establishment of work phases.Through the implementation of schedules in Revit to quantify materials, the economic computation of individual layers was facilitated, enabling a more detailed cost evaluation.Regarding information about the temporal phases of execution, each individual layer was automatically assigned the same phase for both creation and demolition, thereby hindering a nuanced distinction between the layers themselves (Figure 14).Each element within the imported model on Navisworks encapsulated all the information previously entered into the Revit software.The software organized the elements using a selection structure, allowing for the selection of objects or the identification of the selected object type within the model (Figure 15).Each individual element in the selection structure could be associated with an activity, which had to be reciprocally created in the TimeLiner for constructing the 4D model.Following the import into Navisworks, the exploit of selections made possible by shared parameters, previously configured in Revit, allowed for the association of times with planned activities, greatly simplifying the creation of the 4D construction model.Utilizing the assigned times for the model elements in Navisworks also facilitated simulations of the construction process (Figure 16).The allocation of time to different elements automatically produced a Gantt chart, facilitating the scheduling of project completion times (Figure 17).Within the model's temporal parameters, it was also feasible to input both the actual and planned dates of tasks, thereby enabling real-time simulations even during the construction phases.

5D Outputs
Beyond temporal planning data, Navisworks facilitated model integration by incorporating cost, enabling a thorough 5D analysis.The association of costs with activities could be performed by considering either total costs or by breaking them down into categories present in the software: material cost, labor cost, equipment cost, subcontractor cost (Figure 18).From Navisworks, TimeLiner data could be exported in *csv or *.xls format, viewable through electronic spreadsheet software or project management and planning software (Figure 19).However, akin to exporting data from Revit schedules, it was noted that after export, the data were not interpreted correctly and necessitated subsequent corrective interventions.From the conducted tests, it was determined that Navisworks software enables the achievement of BIM levels 4 and 5D, incorporating a high level of detail that extends down to individual elements within the 3D model.However, for complex models seeking an exceptionally detailed 4 and 5D representation, the processes of element selection and the assignment of time and cost parameters can become exceptionally labor-intensive.Navisworks software excels in 4D simulations, particularly when the model is strategically divided into macroscopic work phases, allowing detailed simulations for specific project components that demand heightened attention.
For more comprehensive 5D analyses, specialized applications designed explicitly for this purpose are available.These applications facilitate a smoother extrapolation of information from the 3D BIM model.One such software is ArchVISION RP®, a multilingual plugin for dynamic and direct quantity takeoff in PriMus® by ACCA Software.With its tools, it enables the direct extraction of information from Revit to create cost analyses of the model.
The software streamlined the handling of multi-level WBS structures, the computation of plants and systems, and the estimation of IFC projects imported into Revit.Moreover, it provided a user-friendly way to associate price list items from Primus with model families through Drag&Drop (Figure 20).This application also facilitated the computation of layering and materials constituting the elements, encompassing the features available for Revit system families.After associating the price list items with the model families and configuring the necessary parameters, the software facilitated the direct generation of the quantity takeoff in Primus from the Revit BIM model.This method had the advantage of automatically updating the quantity takeoff with each geometric modification in the 3D model (Figure 21).The addition of new families to the model or modifications to existing ones necessitated a renewed association with the respective price list items.Using the ArchVISION OFFICE tool for Revit, the association of quantity takeoff items with Revit families was seamlessly achieved directly from Microsoft Excel and Word.Each element or its components were linked to their respective price list items, extracted from Excel, and effortlessly dragged into a designated interface within the tool (See Figure 22).
Once the association of items with families was concluded and the required parameters were set within the software, the automatic generation of the quantity takeoff directly into an Excel spreadsheet was successfully accomplished (Figure 23).The utilization of ArchVISION more effectively addressed diverse needs for project computation and facilitated the development of 5D analyses for the project.Additionally, the integration of Revit with PriMus not only managed the metric computation of the works but also extended to other functionalities, including the project's economic framework, calculating the impact of costs related to safety and labor, determining corporate safety charges, and conducting consistency checks-all encapsulated within a unified document directly linked to the Revit BIM model.
Although the Office version of ArchVISION had limited functionalities, it still ensured accurate data export without necessitating manual adjustments, as often required in exports derived from the generation of Revit schedules.

CONCLUSIONS
The case study examining the application of Building Information Modelling (BIM) in Revit for the design of the North-South railway station in Riyadh underscores the transformative impact of advanced technologies on the infrastructure sector.Demonstrating a successful implementation of BIM in Revit, the study reveals substantial improvements in project efficiency, error reduction, and enhanced collaboration across various disciplines involved in station design.The research's forward-looking approach aims to progress seamlessly from a 3D model to 4D and 5D models.The adoption of Autodesk Navisworks for 4D management, coupled with the strategic parameterization of phases in Revit during the design phase, exemplifies an efficient workflow.This approach not only simplifies the selection of elements but also facilitates the extraction of temporal information through the creation of schedules.The phased approach, spanning from defining the construction area to the final integration of all elements, provides a well-organized framework for construction management.The consideration of construction logistics within the BIM model, including precise identification of spaces and pathways, showcases the software's capabilities in facilitating detailed planning and analysis.The study further extends its application to Mechanical, Electrical, and Plumbing (MEP) manufacturing design, illustrating Revit's effectiveness in early detection of challenges and interferences during the design phase.The incorporation of essential components in the mechanical ventilation system underscores the software's capacity to address interdisciplinary concerns seamlessly within a unified platform.The implementation of 4D and 5D analysis using Navisworks represents a well-structured approach to construction project management.Acknowledging certain challenges, particularly in labor-intensive processes for detailed 4D and 5D representations, the study recommends specialized applications like ArchVISION RP as an efficient solution for detailed quantity takeoff and cost analyses.In conclusion, the case study provides a comprehensive exploration of the transformative potential of BIM in Revit for infrastructure design and construction.It not only emphasizes the software's capabilities in design, construction management, and interdisciplinary collaboration but also recognizes the need for specialized tools to address specific aspects of project analysis.

AKNOWLEDGEMENT
This paper has been produced with the financial assistance of the European Union under the ENI CBC Mediterranean Sea Basin Program, for Education, Research, technological development, and Innovation, under the grant agreement n°28/1682.

Figure 1 :
Figure 1: 3D Revit model of the North-South Riyadh Railway Station.

Figure 2 :
Figure 2: 4D/5D BIM implementation flow chart Furthermore, 5D simulation generates models that assess how changes to materials, layouts, and construction methodologies impact the infrastructure layout and costs.This aids in identifying resource utilization over time, with construction costs adjusting automatically in real-time with model changes.The "what-if"

Figure 4 :
a) The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLVIII-2/W4-2024 10th Intl.Workshop 3D-ARCH "3D Virtual Reconstruction and Visualization of Complex Architectures", 21-23 February 2024, Siena, Italy Visualization of selected construction phases modelled in Revit: site organization and installation of systems (a); excavation phase (b); foundation works (c); construction of the structure floor by floor (d); erection of elevated structures (e); installation of roof beams (f).

Figure 6 :
Display of specific families of systems, equipment, and machinery modelled in Revit for the construction phase: inert and concrete production plant (a); machinery used for drilling and casting piles (b); identification of temporary waste deposits for excavated soil (c).

Figure 7 :
Figure 7: Excerpt from a construction equipment and facilities schedule generated using Revit software.

Figure 8 :Figure 9 :
Dynamic presentation of selected elements in the Revit schedule: selection of the element in the schedule (a); Revit command to highlight the element in the model (b); visualization of the selected element in the schedule (c).The schedules produced in Revit were exported as *.txt files, providing the ability to open them in spreadsheet software for a direct extraction of quantities and descriptions of various elements within the BIM model (see Figure 9).While the export feature facilitated data modification and integration, there was a need for formatting adjustments in the exported text file when accessed in a spreadsheet.Additionally, any subsequent changes to the model only refreshed the Revit schedules, necessitating the re-exportation of data for further computations.Excerpt of text file exported from the Revit schedule (a); conversion of the text file into a spreadsheet (b).
Visualization of the modelled mechanical ventilation system in Revit: Basement 3 system view (a); detailed technical view of the ventilation system (b).

Figure 11 :
Figure 11: Excerpts from schedules of the mechanical ventilation system obtained with Revit: ducts schedule (a); mechanical equipment schedule (b).

Figure 12 :
Figure 12: Linking the shared parameters created in Revit to the different elements constituting the model.The choice of components constituting composite elements, like walls, in Navisworks, had to be made explicitly within the model selection structure.An alternative option would have involved creating the wall directly in Revit as individual, separate layers rather than as an element composed of different layers (Figure13).

Figure 14 :
Figure 14: Materials quantification schedule for a wall, including the identification of individual layers.

Figure 15 :
Figure 15: Identification of elements in the selection structure of Navisworks.

Figure 16 :
Figure 16: Assigning timelines in Navisworks to different elements of the model.

Figure 17 :
Figure 17: Gantt chart generated in Navisworks by assigning timelines to selected elements in the model.
Assigning costs in Navisworks to activities (a); categories of costs that can be assigned in Navisworks (b).

Figure 20 :
Figure 20: Integration, with ArchVISION RP, of Primus price lists with families within the Revit model.

Figure 21 :
Figure 21: Creation of the quantity takeoff on Primus with ArchVISION RP, directly derived from the Revit model.

Figure 22 :
Figure 22: ArchVISION OFFICE tool interface for linking a family in the Revit model to a price list item.

Figure 23 :
Figure 23: Generating the quantity takeoff calculation in EXCEL using ArchVISION OFFICE, with the Revit model as input.