• 한국BIM학회 논문집
• /
• 제9권3호
• /
• pp.1-7
• /
• 2019

Digital twin technology has been actively developed to monitor and assess the current state of actual structures. The digital twin changes the traditional observation method performed in the field to the real-time observation and detection system using virtual online model. Thus, this study designed a digital twin model for a beam and examined the feasibility of the digital twin for bridges. To reflect the current state of the bridge, model updating was performed according to the field test data to construct an analysis model. Based on the constructed bridge analysis model, the relationship between strain and displacement was used to represent a virtual model that behaves in the same way as the actual structure. The strain and displacement relationship was expressed as a matrix derived using an approximate analytical theory. Then, displacements can be obtained using the measured data obtained from strain sensors installed on the bridge. The coordinates of the obtained displacements are used to construct a virtual digital model for the bridge. For verification, a beam was fabricated and tested to evaluate the digital twin model constructed in this study. The displacements obtained from the strain and displacement relationship agrees well with the actual displacements of the beam. In addition, the displacements obtained from the virtual model was visualized at the locations of the strain sensor.

• Steel and Composite Structures
• /
• 제46권6호
• /
• pp.731-744
• /
• 2023

Vehicle load information is an important role in operating and ensuring the structural health of cable-stayed bridges. In this regard, an efficient and economic method is proposed for vehicle load detection based on the observed cable tension and vehicle position using a graph neural network (GNN). Datasets are first generated using the practical advanced analysis program (PAAP), a robust program for modeling and considering both geometric and material nonlinearities of bridge structures subjected to vehicle load with low computational costs. With the superiority of GNN, the proposed model is demonstrated to precisely capture complex nonlinear correlations between the input features and vehicle load in the output. Four popular machine learning methods including artificial neural network (ANN), decision tree (DT), random forest (RF), and support vector machines (SVM) are refereed in a comparison. A case study of a cable-stayed bridge with the typical truck is considered to evaluate the model's performance. The results demonstrate that the GNN-based model provides high accuracy and efficiency in prediction with satisfactory correlation coefficients, efficient determination values, and very small errors; and is a novel approach for vehicle load detection with the input data of the existing monitoring system.

• 한국BIM학회 논문집
• /
• 제6권1호
• /
• pp.25-32
• /
• 2016

In BIM environments for infrastructures, civil structures such as road, bridge and tunnel etc., created into 3D objects, integrated with their properties, securing BIM design productivity is very critical during 3D modeling. To solve this issue, configuring BIM libraries so that the users can utilize prefabricating in advance 3D objects that have been applying repeatedly during BIM design is essential so much. Current BIM libraries have made focused on Ready-Made for architectural facilities. However, establishing environment for delivering BIM library for civil facilities is very sparse. Accordingly, this study developed a web-based sharing system for delivering BIM library contents based on standardized drawing for civil area. To do this, we have analyzed core features and operation system of BIM library sharing system in domestic and overseas. Besides, functional requirements that are necessary for developing BIM library sharing system was derived, and through operation scenario configuration, the web-based system was developed according to the detailed mechanism. It is expected that this system can enhance BIM design productivity during library based modeling, and can be utilized as construction supporting tools that can help construction managers to make a design change.

• 한국BIM학회 논문집
• /
• 제7권1호
• /
• pp.1-8
• /
• 2017

Aesthetic design guidelines of bridges were developed in many countries. As iconic structures, bridges need to be attractive and durable as they serve many generations. In this paper, a new design process of concrete structures considering 3D shapes and texture was proposed. The 3D design needs to consider function, economy, advanced technology, tradition and local culture. 3D printers enable the combination of artistic design and engineering design for concrete structures. Parametric modeling with iconic design was utilized to produce 3D formworks. As a pilot project, a railway bridge girder was designed and the proposed technologies were applied. Detail requirements to improve constructability and quality of concrete surfaces were derived. From the pilot applications, design guidelines were suggested.

• 농촌계획
• /
• 제23권1호
• /
• pp.1-10
• /
• 2017

네트워크를 분석하는 방법인 stochastic 기반의 community bridge node finder는 네트워크 구조의 일부 정보만을 이용하여 중심지 및 확산 경로의 유추가 가능하다. 그러나, heterogeneity 네트워크에 적용하기 어려운 단점을 보유하고 있어, 본 연구에서는 이를 개선하고자 하였다. heterogeneity 네트워크에 적용할 수 있는 community bridge node finder 방법을 개발하기 위해 네트워크의 modularity를 계측하는 방법을 적용하였으며, 개선된 방법을 통해 community bridge node를 정량적으로 평가할 수 있어 heterogeneity 네트워크의 분석이 가능하였다. 농촌계획분야 정보의 경우, 대부분 자료의 불확실성이 존재하며 무결성이 떨어지는 특성을 가지고 있는 바 본 연구에서 적용한 전염병 확산 예측 뿐만 아니라 개선된 방법을 활용할 경우 주산지 정비 거점 분석 등 다양한 형태로 이용될 수 있을 것으로 기대된다.

• 한국BIM학회 논문집
• /
• 제6권3호
• /
• pp.42-48
• /
• 2016

Structural members are designed to maintain the load-carrying capacity as well as structural strength, and the structural serviceability such as the deflection, cracks, and vibration to give the occupants uncomfortable environment should be checked. Recently, the importance of the vibration has been issued since the Techno Mart accident due to vibration resonance. This study provides a passive vibration control system using the repulsion force of magnets to reduce dynamic vibrations. The systems is devised by importing the constraint condition by a hinge to operate magnets installed at two adjacent locations. The effectiveness of the proposed system is investigated by the vibration control test of a steel beam with and without the control system. It is illustrated in the test that the system is activated by the control forces executed by the magnets and can be utilized in reducing the dynamic responses. The system can be applied to pedestrian bridge and traffic bridge. The applicability is expected in the future by optimizing the factors to affect the dynamic responses like the intensity, mass, locations of magnets.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2011년도 정기 학술대회
• /
• pp.103-106
• /
• 2011

현재 국내의 건설 산업은 BIM(Building Information Modeling)이라는 새로운 패러다임으로의 변화를 모색하고 있다. 이미 국내 건축업계에서는 적극적으로 BIM개념이 도입되고 있으며 주로 국가 기반시설의 건설업무를 분담하고 있는 토목업계에서는 현재 BIM개념을 도입하기 위한 준비과정에 있는 단계이다. 이 연구에서는 대표적인 토목구조물인 교량을 대상으로 BIM개념 도입의 필요성과 교량을 건설하기위한 여러단계 중에서도 그 출발점이라 할 수 있는 구조설계 단계에 있어서 BIM개념의 도입 방법과 기존의 구조설계 프로세스를 BIM기반의 구조설계 프로세스로 변화하기 위하여 필요한 작업들에 대한 분석을 수행하였으며 결과적으로 교량 프로젝트에 대하여 BIM기반의 구조설계를 위한 최적의 프로세스를 구축하기 위한 연구를 수행하였다.

• 한국CDE학회논문집
• /
• 제3권1호
• /
• pp.48-56
• /
• 1998

Finite element analysis is very important in the design and analysis of mechanical engineering. The process of FEA encompasses shape modeling, mesh generation, matrix solving and post-processing. Some of these processes can be tightly integrated with the current software architectures and data sharing mode. However, complete integration of all the FEA process itself and the integration to the manufacturing processes is almost impossible in the current practice. The barriers to this problem are inconsistent data format and the enterprise-wise software integration technology. In this research, the information model based on STEP AP209 was chosen for handling finite element analysis data. The international standard for the FEA data can bridge the gap between design, analysis and manufacturing processes. The STEP-based FEA system can be further tightly integrated to the distributed software and database environment using CORBA technology. The prototype FEA system DICESS is implemented to verify the proposed concepts.

• 한국건설관리학회논문집
• /
• 제13권2호
• /
• pp.11-24
• /
• 2012

최근 공공사업 발주조건에 BIM(Building Information Modeling)이 의무화되고 있고, 실무 도입을 통한 성공 사례가 증가되면서 건설 분야의 BIM 도입이 본격화되고 있다. 그러나 기존의 BIM 관련 연구는 대부분 설계 또는 시공단계에 한정되어 수행됨에 따라 건설프로젝트의 생애주기를 고려하지 못하고 있고, 특정 업무지원 기능 위주로 진행되고 있다. 따라서 본 연구에서는 건설공사 프로젝트의 기획부터 유지관리단계의 생애주기 동안 단계별 BIM 적용이 가능한 통합 BIM 운영 프로세스를 제안하고 이를 토대로 통합 BIM 시스템을 개발한다. 이를 위해 교량공사를 대상으로 수행단계별 정보체계를 분석하여 BIM 활용 기능과 적용 프로세스를 제시하였으며, 이에 근거하여 수행단계별 BIM 운영 시스템을 구축하였다. 연구에서는 개발된 시스템의 실무 적합성 검증을 위해서 사례적용과 건설 실무자의 활용성 설문 조사를 수행하였다. 이러한 BIM 통합 운영체계는 생애주기를 고려한 건설공사의 3차원 기반 통합정보관리체계로 활용성이 기대된다.

• 한국환경과학회지
• /
• 제4권1호
• /
• pp.81-90
• /
• 1995

In order to provide the basic information for the water quality modeling, the water pollution indicators of Sin stream and Keumho river flowing through Taegu city were measured, and the Periodical variations of these indicators were studied under the condition of stagnating for 19 days. For this experiment, three sampling sites(Sungpook bridge, Mutae bridge and Gangchang bridge) were selected. Sungpook bridge is located most down the Sin stream, Mutae bridge and Gangchang bridge are located on the lower Keumho river. The results were as follows. 1. The values of water pollution indicators measured at Mutae bridge were pH 8.7, TSS 51mg/1, TS 383mg/1, Cl- 60.68mg/1, turbidity 32FTU, DO 8.58mg/1, oxygen deficit 2.02mg/1, COD 16.32mg/1, organic carbon 13.60mg/1. 2. At Gangchang bridge located down more than Mutae bridge, the values of these indicators were pH 8.0, TSS 26mg/1, TS 737mg/1, Cl- 90.59mg/1, turbidity 37FTU,DO 3.49mg/1, oxygen deficit 7.11mg/1, COD 28.02mg/1, organic carbon 14.28mg/1. 3. At Sungpook bridge, the values of these indicators were pH 8.3, TSS 145mg/1, TS 344mg/1, Cl- 32.51mg/1, turbidity 60FTU, DO 6.53mg/1, oxygen deficit 4.07mg/1, COD 43.79mg/1, organic carbon 11.03mg/1. 4. At Mutae bridge and Sungpook bridge of which initial DOs were high, DOs have decreased under the condition of stagnating for 7 days and increased after that time. On the contrary, at Gangchang bridge of which oxygen deficit was very high(7.11mg/l), DO have increased under the condition of stagnating for 13 days and decreased after that time 5. All the samples showed the quick decrease of CODs and organic carbons under the condition of stagnating for 19 days. Nevertheless, at Sungpook bridge ·of which initial COD was yeW high(43.79mg/1), the value of COD measured at the last day of experiment was still high(21.35mg/1) because of a large quantity of reducing inorganic matters. 6. All the samples didn't show the distinct decrease of turbidities because of a large quantity of nonbiodegradable inorganic solids.