Leen-Seok Kang

Development of workspace conflict visualization system using 4D object of work schedule

Generally, workspace conflict analysis between construction activities by a 3D or 4D CAD system is performed for checking the conflict between element bodies. However, in case of many projects which consist of diverse activities in limited area, the workspace conflict analysis for reducing interferences caused by labor or equipment work is also an important management factor. In particular, if some activities are constructed adjacent to the overlap period, the workspace for those activities may be conflicting. Workspace conflicts decrease work productivity, and accidents can occur. Therefore, it is desirable that the workspace conflict should be minimized in order to perform efficient work. This paper presents a methodology that generates workspaces using a bounding box model and an algorithm in order to identify schedule and workspace conflict. Additionally, a workspace conflict verification system was developed to analyze the workspace information by integrating algorithms that include the automated generation of workspace models and an automatic check of workspace conflict within a 4D simulator. If a project manager can identify the workspace conflict using the system described, the overlapped activities can be rescheduled to minimize the conflict. A case study of a bridge project has been conducted to evaluate the practical applications and feasibility of the developed system. Therefore, the safety and constructability of a project can be improved by the workspace analysis system.

BIM-Based Construction Scheduling Method Using Optimization Theory for Reducing Activity Overlaps

AbstractAs building information modeling (BIM) systems continue to be widely adopted, there is an increasing demand for an active construction schedule management system with more advanced decision-making capabilities. For example, if overlapping between construction activities is significant, the performance of construction operations for the corresponding activities may deteriorate. Thus, a viable construction schedule should be formulated in order to minimize overlapping of proximate construction activities. An active system can be regarded as a certain solution for this issue. The purpose of this study is to develop a systematic methodology and computer system for an optimal construction schedule simulation that minimize overlapping activities for the enhancement of a project’s operational performance. This study centers on identifying overlapping activities, applying fuzzy theory, and analyzing risk levels for schedule overlap issues. In addition, genetic algorithm (GA) theory is adopted for the mini...

Development of 5D CAD System for Visualizing Risk Degree and Progress Schedule for Construction Project

D CAD system visualizes the schedule data for construction project. Generally, 5D CAD system visualizes construction cost or resource data by linking 4D object. This study attempts to develop a 5D CAD system by linking 4D object for progress schedule data with the risk data for visualizing construction risk degree of each activity. This system uses the fuzzy analysis and AHP analysis procedures to estimate risk degree of each activity. And the system considers construction cost, duration and dangerous condition of work site as risk factors. The estimated risk degree of each activity is simulated with different colors by the risk level in 4D CAD engine that developed in this study. Because the 5D CAD system integrated with risk analysis data has creative functions comparing with the current similar systems, it can be a useful tool for visualizing practical risk data and progress schedule data.

Usability Improvement of BIM for Construction Projects Using Active BIM Functions

Most current BIM systems are focused on the visual information of work status in the design and construction stages. In a passive BIM system, 3D CAD tool can visualize the interference elements of design drawings, however, it cannot suggest a solution to solve the interference status. And 4D CAD tool in the construction stage can simulate the appearance of each activity by construction schedule, however, it cannot suggest an optimized schedule plan considering specified schedule condition of the project. Recently, many organizations need BIM solutions that can improve the work status beyond the level of simple visual information from BIM system. Active BIM system can provide the solutions to the project manager. This study suggests active BIM functions for the solutions and attempts to develop a 4D CAD engine to validate the usability of the functions.

Development of Improved 4D CAD System for Horizontal Works in Civil Engineering Projects

One of the purposes of using four-dimensional (4D) computer-aided design (CAD) system is to express numeric construction schedule data into a visual format. While existing 4D CAD systems are appropriate for building projects composed of vertical schedule progress and manufactured elements, the basic functions of those systems have limitations when directly applied to a civil engineering project, such as highway and railway facilities. Such projects include horizontal works, and their activities are carried out according to the elements of natural topography. This study attempts to develop a 4D CAD engine that supports analysis of the 4D objects for horizontal elements including a visual simulation of a cutting and filling status of an earthwork section in civil engineering projects. The system uses integrated information management techniques employing work breakdown structure for simulating 4D objects for each level. The developed engine includes new functions for visualizing work schedule and activity progress in highway and railway project with horizontal earthwork. Finally, to improve the practical applicability of a 4D CAD system, a new method for visualizing risk analysis data is suggested for future studies.

Grid cell-based algorithm for workspace overlapping analysis considering multiple allocations of construction resources

Abstract When multiple workspaces for resources are allocated within a narrow work area, the constructability of work may deteriorate based on the conflicts that occur due to the mutual adjacency levels between the workspaces. In this situation, the identification of the workspace overlapping status is essential for establishing the optimized layout planning of workspaces. However, current 3D environments consider only physical collision and reaction by the cross verification of geometric properties to detect collisions between 3D objects. Thus, the configuration of methodology to visually check the overlapping level of workspaces with conflicting status is insufficient for a successful interference management. This study develops a new grid cell-based analysis algorithm and its 4D simulation system for visually verifying the workspace overlapping of dynamic resources to be allocated multiply within a confined area, such as a tunnel or underground facility. The proposed algorithm and system can assist in the intensive management of activities that have a high level of workspace overlap by visualizing their overlapping level.

Development of BIM Functions and System for Construction Project Through Project Life Cycle-Focusing on Bridge Construction Project-)

Recently, BIM (Building Information Modeling) technique is being considered as a critical delivery condition for the public projects according to the increase of best practices by practical application of BIM. However, since existing BIM studies are focused on the design and construction phases, those results are not considering the life cycle of a construction project. Therefore, this study suggests an integrated BIM operation process that enables an application of BIM for each phase of a construction project from planning to maintenance phases and develops an integrated BIM system based on the suggested methodologies. This study developed basic BIM functions and its application process by analyzing information systems in each project phase for a bridge construction project. Besides, this study performed case study and survey analysis for construction managers to verify a practical applicability of the developed system. Therefore, it is expected that the integrated BIM system is going to be utilized as a 3D-based integrated information management system considering life cycle of construction projects.

A Comparative Analysis on Generated Construction Waste Quantities in a Case Study for Deconstruction of an Apartment

Abstract : Deconstruction of the building must be applied firstly in order to improve recycling and reuse of construction wastes. In this study have done a case study for deconstruction of an apartment. All construction waste(CW) which will be generated during deconstruction was examined in each part of the building. Because drawing did not exist in most of the old building, we drew up floor plans of buildings. After analyzing these drawings, estimated quantities of CW. It was measured working time of labor and equipments for deconstruction and general demolition on each building of the apartment. In addition, it was proposed in the volume and weight per unit after analyzing detailed measurement of CW which was generated in the process of deconstruction and traditional demolition. It suggested recovery rate at a site, volume and weight conversion factors, and waste basic unit per area that based on the results of comparative analysis on the amount of CW which is calculated from drawing and generated at a site. These factors will be used fundamental materials for estimating quantities and treatment cost of CW, and scheduling of works.

Prototype model of wireless maintenance operation system for bridge facility using VR and ubiquitous technology

Building information modeling (BIM) is a representative IT tool for construction project management. BIM includes virtual reality (VR) and augmented reality (AR) simulations for construction object. Specially, VR is a useful tool for visualizing construction process to check a design error or construction error in virtual space before real construction. This study suggests a framework to use a wireless maintenance method for a bridge facility using VR, RFID and ubiquitous tools. Due to the issues such as omission of data, document based management, maintenance based on measurement data and wire-based network, it is difficult for the existing maintenance system of bridges to act to diverse characteristics of site and environmental changes in real time. With these reasons, there are many constraints in establishing active maintenance strategies for bridge facility. To solve these issues, this study suggests an integrated maintenance model for a bridge facility based on VR and ubiquitous technology to build a smart maintenance operation system. It is expected that the suggested model will be utilized as a framework model in order to build a smart maintenance operation system from collection of maintenance data to visualization of them for bridge facility.

Development Strategies and Feasibility Evaluation of Maintenance Operation System for Railway Bridge Based on Ubiquitous-BIM Technology

Due to the issues such as omission of data, document based management, maintenance based on measurement data and wire-based network, it is difficult existing maintenance system for railway bridges to act to diverse characteristics of site and environmental changes in real time. With these reasons, there are many constraints in establishing active maintenance strategies for railway bridges. To solve these issues, this study suggests an integrated maintenance business model based on practical utilization and information management based on BIM technology to build a smart maintenance operation system based on ubiquitous computing for railway bridges. To secure its development and practical applications, a quantitative evaluation by questionnaire analysis was performed. Therefore, it is expected that the suggested model will be utilized as a framework model in order to build the smart maintenance operation system from collection of maintenance data to action for railway bridges.