• Smart Structures and Systems
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• v.5 no.4
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• pp.469-482
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• 2009

The emerging sensor-based structural health monitoring (SHM) technology has a potential for cost-effective maintenance of aging civil infrastructure systems. The author proposes to integrate continuous and global monitoring using on-structure sensors with targeted local non-destructive evaluation (NDE). Significant technical challenges arise, however, from the lack of cost-effective sensors for monitoring spatially large structures, as well as reliable methods for interpreting sensor data into structural health conditions. This paper reviews recent efforts and advances made in addressing these challenges, with example sensor hardware and health monitoring software developed in the author's research center. The hardware includes a novel fiber optic accelerometer, a vision-based displacement sensor, a distributed strain sensor, and a microwave imaging NDE device. The health monitoring software includes a number of system identification methods such as the neural networks, extended Kalman filter, and nonlinear damping identificaiton based on structural dynamic response measurement. These methods have been experimentally validated through seismic shaking table tests of a realistic bridge model and tested in a number of instrumented bridges and buildings.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.6
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• pp.483-500
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• 2007

Emerging sensor-based structural health monitoring (SHM) technology can play an important role in inspecting and securing the safety of aging civil infrastructure, a worldwide problem. However, implementation of SHM in civil infrastructure faces a significant challenge due to the lack of suitable sensors and reliable methods for interpreting sensor data. This paper reviews recent efforts and advances made in addressing this challenge, with example sensor hardware and software developed in the author's research center. It is proposed to integrate real-time continuous monitoring using on structure sensors for global structural integrity evaluation with targeted NDE inspection for local damage assessment.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.479-486
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• 2009

This paper presents an integrated real-time monitoring and control framework that facilitates decision making by enabling project managers to take corrective actions right after any deviation happens and mitigate the damage to the ongoing steel projects. The proposed framework employs the High Level Architecture (HLA) as its infrastructure. It is composed of several individual monitoring and control components called "Federates," which cooperate and interact with each other through the Real-time Infrastructure (RTI). Reusability, interoperability and extendibility of federates in the proposed project control system make this a unique system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.2
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• pp.677-685
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• 2014

Despite the significant benefits of BIM (Building Information Modeling), it is not being vitalized for the facilities that are designed based on the horizontal and vertical alignments because of the lack of flexibility in manipulating surface models generated based on alignments. Alignment-based design produces a surface model in one piece through the definition of the typical cross-section along the alignment. Therefore, linking these alignment-based 3D surface models, that are not modularized and difficult to partition, to the required attribute information is very difficult This paper presents design of a flexible BIM technology suitable for the alignment-based civil infrastructure by providing the partitioning functionality for surface models, the contents library for cross-sectional design components, and the attribute information along with the critical functionalities needed for the design, construction and maintenance of alignment-based civil infrastructure.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.1
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• pp.71-76
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• 2017

In BIM design, the construction and use of a library are very important. Since the existing contents can be re-used, the design can be executed more effectively and efficiently. Unlike the construction, the civil engineering, in particular, the railroad sees an inappropriate development and standardization of libraries. Thus, this study aims to develop and standardize the 3D object library in the railroad facility. We first gather and analyze the railroad facility breakdown structure and relevant drawings. We then match the items of analyzed standard drawings and the breakdown structure items. It was reviewed whether the library was required according to all items, and if required, it was reviewed what software was proper. Available software were found to be Civil 3D, Revit, etc. Based on this analysis, we will design the attribute items and specifications of the 3D railroad infrastructure library, as well as construct the library thereof.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.5
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• pp.675-687
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• 2023

The border area between the South and North Korea is considered a stage for promoting Green Détent through the transformation of the Demilitarized Zone into the Green Peace Zone. This paper proposes 'Prosuming-index' composed of items to evaluate the multi-layered nature of industrial and infrastructure projects in the ecological and environmental fields planned in the border area. Based on the prosuming-index, we derived the following four types of potential for Green Detent practice in the border area-first, the Incheon and Ganghwa regions as 'a logistics/human network and agricultural/fishery production area', second, the northern Gyeonggi region as a 'cooperative network area based on the smart technology industries', third, the western Gangwon and the parts of nothern Gyeonggi region, as 'a multiple prosumer's area based on carbon neutral technologies', lastly, the eastern Gangwon region, as 'a transition area from idle or aged infrastructure to green infrastructure through the renewable energy industries'.

• Korean Journal of Computational Design and Engineering
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• v.19 no.3
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• pp.281-293
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• 2014

Although there have been a lot of BIM R&Ds in the civil engineering and their applications to the real projects, BIM in the field is still known to be behind the other areas. One of the reasons for this should be that the civil projects is generally too public for private participants to try new technologies, but it is mainly because the projects are so huge and complex that we still have the working environment where the systematic information sharing or exchanging is not smooth enough. In this paper, we are verifying the possibility and proposing the direction of BIM information standardization technology in civil engineering based on the integrated BIM information standard framework. For this purpose, after reviewing the introduction plan for BIM information framework, we applied it to an actual civil structure for test. The implementation result proved that the framework has possibility and effectiveness for the takeoff and construction cost calculation, which confirmed the standard framework needs to be extended consistently. This study is expected to contribute to the standard system establishment and its technology propagation for BIM development in the civil engineering.

• Structural Monitoring and Maintenance
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• v.9 no.4
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• pp.359-371
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• 2022

Bridges are critical to the civil engineering infrastructure network as they facilitate movement of people, the transportation of goods and services. Given the aging of bridge infrastructure, federal officials mandate visual inspections biennially to identify necessary repair actions which are time, cost, and labor-intensive. Additionally, the expansion joints of bridges are rarely monitored due to cost. However, expansion joints are critical as they absorb movement from thermal effects, loadings strains, impact, abutment settlement, and vehicle motion movement. Thus, the need to monitor bridge expansion joints efficiently, at a low cost, and wirelessly is desired. This paper addresses bridge joint monitoring needs to develop a cost-effective, real-time wireless system that can be validated in a full-scale bridge structure. To this end, a wireless expansion joint monitoring was developed using commercial-off-the-shelf (COTS) sensors. An in-service bridge was selected as a testbed to validate the performance of the developed system compared with traditional displacement sensor, LVDT, temperature and humidity sensors. The short-term monitoring campaign with the wireless sensor system with the internet protocol version 6 over the time slotted channel hopping mode of IEEE 802.15.4e (6TiSCH) network showed reliable results, providing high potential of the developed system for effective joint monitoring at a low cost.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.1
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• pp.121-128
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• 2016

The restructuring of Korean railway industry, separation of between train operators and an infrastructure manager, had been conducted in 2004 to increase the productivities of railway operations. However, the maintenance-staffs are still employed by Korail (train operator), not by the infrastructure manager, which led the maintenance of railway infrastructure to be conducted by the train operator. The infrastructure manager is now only taking care of financial transferring issues once the train operator requests expenses spent for facility maintenance. Such incomplete restructure may result in a lack of safety performance on railway operations as the roles and responsibilities are less likely to be assigned under the multiple train operators. Thus, this study proposes the way of structuring maintenance divisions and their roles and responsibilities to assure the safe work execution under the circumstance of multiple train operators on the same rail network.

• Journal of Korean Society of Water and Wastewater
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• v.37 no.6
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• pp.335-345
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• 2023

In Korea, as part of the Green New Deal project toward a carbon-neutral society, it is necessary to build a climate-resilient urban environment to green the city, space, and living infrastructure. To this end, SWMM-ING was improved and the model was modified to analyze the carbon reduction effect. In addition, I plan to select target watersheds where urbanization is rapidly progressing and evaluate runoff, non-point pollution, and carbon reduction effects to conduct cost estimation and optimal design review for domestic rainwater circulation green infrastructure. In this study, green infrastructure facilities were selected using SWMM-ING. Various scenarios were presented considering the surface area and annual cost of each green infrastructure facility, and The results show that the scenario derived through the APL2 method was selected as the optimal scenario. In this optimal scenario, a total facility area of 190,517.5 m² was applied to 7 out of 30 subwatersheds to achieve the target reduction. The target reduction amount was calculated a 23.50 % reduction in runoff and a 26.99 % reduction in pollutant load. Additionally, the annual carbon absorption was analyzed and found to be 385,521 kg/year. I aim to achieve additional carbon reduction effects by achieving the goal of reducing runoff and non-point pollution sources and analyzing annual carbon absorption. Moreover, considering the scale-up of these interventions across the basin, it is believed that an objective assessment of economic viability can be conducted.