Changyoon Kim

Ubiquitous Sensor Network for Construction Material Monitoring

Timely acquisition of construction resource information is an essential task for construction engineers and managers. Due to the harsh and dynamic construction environment, it is not easy to acquire construction information in real time. This paper presents a radio frequency identification (RFID) and ZigBee (IEEE 802.15.4)-based system to manage materials on a busy construction site where a data communications system is not in place. RFID tags are attached to and used to identify various kinds of construction materials, and the ZigBee communication technology is used to wirelessly transfer this information. To confirm the viability of our system, the RFID and ZigBee technologies were assessed using an indoor experiment. Following this, a field experiment was then conducted. On a building construction site, a range of construction materials was identified using RFID tags and this information was transferred to an end user with the help of ZigBee multihop networking. The results of the field experiment showed an acceptable reading range and rate for the proposed system. Therefore, the integrated system with RFID and ZigBee modules demonstrated great potential for improving the existing management processes for construction resources on large and complex construction sites.

Applicability of 4D CAD in Civil Engineering Construction: Case Study of a Cable-Stayed Bridge Project

Four-dimensional (4D) computer-aided design (CAD) has been credited with improving construction planning procedures. The integration of three-dimensional CAD with schedule information has enabled the effective detection of design and planning flaws in many construction projects. However, the benefit of 4D CAD has been centered on architectural constructions, as other areas such as civil infrastructure have seldom been the target of 4D CAD application. This paper presents a case study in which a cable-stayed bridge construction was analyzed and modeled using the 4D graphic simulation approach. The cable-stayed bridge was chosen for the case study because it suitably represents the complex nature of modern civil infrastructure. 4D CAD models were developed at three different levels of detail: activity, discrete operation, and continuous operation. The clear definitions of the three levels of detail of 4D CAD and their application results for the cable-stayed bridge are presented herein.

Mobile computing platform for construction site management

Ever improving smart phones and mobile computing technologies provide engineers unprecedented opportunities to innovate the existing processes of construction projects. Researchers in the construction industry tried to use mobile computing technologies for enhancing the management process of construction project on site. This study aims to present a location-based construction site management system using a mobile computing platform. The system was developed using iPhone SDK (Software Development Kit) from Apple Inc. Task information provided in the system was easily associated with the corresponding location information. This unique feature enabled the construction engineers to easily understand where the tasks and problems were. The communication capability of mobile devices through construction drawing presentation also offered effective information exchange among construction participants. The mobile system operated on smart phone is expected to assist construction engineers in achieving real-time access to customized, location-based construction information.

Interactive 3D CAD for Effective Derrick Crane Operation in a Cable-Stayed Bridge Construction

The high expectation of esthetic and functional quality in modern civil infrastructure has resulted in the increased demand for long span bridges. In advanced or developing countries, long span bridges such as cable-stayed and suspension bridges are considered even as landmarks that symbolize the prosperity or culture of the region. These long span bridges require higher level of design and construction technologies than other types of bridges. In particular, the construction of cable-stayed bridges involves precise and sophisticated operation of construction equipment such as derrick cranes. However, it is not easy to plan the operations of a derrick crane before the actual construction process takes place. Unexpected spatial constraints in the construction site may hinder the smooth operation of a derrick crane, which leads to lower than expected productivity and safety. This study applies interactive three-dimensional (3D) computer aided design (CAD) to the derrick crane operation for the purpose of id...

RFID and CCTV-Based Material Delivery Monitoring for Cable-Stayed Bridge Construction

The effective management of construction materials is critical to the successful execution of large-scale infrastructure projects. A cable-stayed bridge construction, for which diverse and complex structural components must be monitored, is no exception. To improve the effectiveness and efficiency of bridge-component management, we developed a material delivery monitoring system using closed-circuit television (CCTV) and radio frequency identification (RFID) technologies. The RFID technology was used to identify the structural components of the cable-stayed bridge; CCTV cameras acquired site image data that helped field engineers confirm the delivery of construction components. The RFID information and image data were saved to a main server database for systematic management of construction materials. A case study conducted at a cable-stayed bridge construction site verified the applicability and capability of the developed system. The system has considerable potential to significantly improve the current...

Interactive Modeler for Construction Equipment Operation Using Augmented Reality

AbstractTo ensure an efficient and safe construction operation, efforts have been made to develop a planning tool that focuses on equipment utilization. With the development of augmented reality (AR) technology came an opportunity for collaborative and interactive scenario modelling of construction equipment operation. This paper presents a system for identifying the optimum scenario for equipment operation by intuitively operating the equipment in an AR environment. Augmented reality was coupled with transmission control protocol/internet protocol (TCP/IP) socket programming to form an interactive interface for multiple users. In this system, users can develop a construction scenario involving equipment operation and site conditions such as project progress and share the idea with other users in distant locations. The interactive modeler can test various situations to find the particular scenario that works the best under the surrounding spatial constraints. A case study involving construction of a real ...

Resource Management in Civil Construction Using RFID Technologies

Large amount of construction resources and their scattered locations in a civil construction site make it extremely difficult for project managers to effectively utilize the resources. In order to manage construction resource effectively, a Radio Frequency Identification (RFID) technology was used in this research. RFID tags for metallic objects were attached to structural components used in a cable-stayed bridge. The RFID reader and antennas were installed at the construction site for tracking the structural components and the acquired data were transferred to the head office via Local Area Network (LAN). The proposed RFID system enabled real-time monitoring of the construction materials in the civil construction site.

Bridge Construction Progress Monitoring Using Image Analysis

Construction progress monitoring is a critical task for construction managers. Traditionally, site superintendents walk the construction site to verify the progress report and understand the current state of construction processes. To get rid of the time consuming process, this research proposes a construction progress monitoring system comprised of a network type closed-circuit television (CCTV) camera, a wireless local area network, and image processing techniques. A civil engineering construction site was selected and the system is able to capture the images of the construction processes. In this paper, the hardware architecture of the system and its initial application results are presented with some promising outcomes.

On-site Safety Management Using Image Processing and Fuzzy Inference

Construction is generally conducted in highly changeable site conditions due to operation of machinery, transfer of materials, moving workers, and changing progress status. Such dynamic characteristics can always lend themselves to the potential for safety accidents. However, it is not easy to have a generalized safety management system that can universally apply to every job site. Although there are some guidelines for safety management, their application to a construction site has to be tailored to satisfy the unique nature of the particular project. Based on the good understanding of the particular site, effective and appropriate safety management process should be derived for workers to be protected from potential dangers of the site. This paper presents an on-site safety management methodology based on image processing and fuzzy inference. Image processing is used to extract spatial information of workers; fuzzy inference is then used to provide the workers a proper level of safety warning based on the spatial information. Contextual site information, such as equipment operations and density of workers, also constitute the on-site safety management methodology. The proposed methodology is expected to provide a safer working environment for construction workers, through its capability to easily customize the safety management system for a construction site.

Error-Correction Methods for Construction Site Image Processing under Changing Illumination Conditions

AbstractImage processing is an effective tool for automated monitoring of construction projects. For the last decade, it has gained increasing acceptance in its application to progress monitoring, productivity analyses, and quality assurance. However, a notable downside exists in image processing, especially in outdoor applications such as construction project monitoring: image quality is heavily affected by ambient lighting conditions. Poor or undesirable lighting conditions produce substandard quality images, which generally lead to a high level of errors in the related image processing for information extraction. This paper presents error-correction methods that can improve the image processing results for construction progress monitoring in the postprocessing stage. The methods are applied in the postprocessing stage. The key idea behind the error-correction methods is the concept of priority to classify input images and project information into several categories based on data reliability and intelli...