• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.1250-1251
• /
• 2022

Measuring management is an important part of preventing the collapse of retaining walls in advance by evaluating their stability with a variety of measuring instruments. The current work of measuring management requires considerable human and material resources since measurement companies need to install measuring instruments at various places on the retaining wall and visit the construction site to collect measurement data and evaluate the stability of the retaining wall. It was investigated that the applicability of the current work of measuring management is poor at small and medium-sized urban construction sites(excavation depth<10m) where measuring management is not essential. Therefore, the purpose of this study is to develop a laser sensor-based hardware to support the wall displacement measurements and their control software applicable to small and medium-sized urban construction sites. The 2D lidar sensor, which is more economical than a 3D laser scanner, is applied as element technology. Additionally, the hardware is mounted on the corner strut of the retaining wall, and it collects point cloud data of the retaining wall by rotating the 2D lidar sensor 360° through a servo motor. Point cloud data collected from the hardware can be transmitted through Wi-Fi to a displacement analysis device (notebook). The hardware control software is designed to control the 2D lidar sensor and servo motor in the displacement analysis device by remote access. The process of analyzing the displacement of a retaining wall using the developed hardware and software is as follows: the construction site manager uses the displacement analysis device to 1)collect the initial point cloud data, and after a certain period 2)comparative point cloud data is collected, and 3)the distance between the initial point and comparison point cloud data is calculated in order. As a result of performing an indoor experiment, the analyses show that a displacement of approximately 15 mm can be identified. In the future, the integrated system of the hardware designed here, and the displacement analysis software to be developed can be applied to small and medium-sized urban construction sites through several field experiments. Therefore, effective management of the displacement of the retaining wall is possible in comparison with the current measuring management work in terms of ease of installation, dismantlement, displacement measurement, and economic feasibility.

• 한국안전학회지
• /
• 제35권4호
• /
• pp.15-22
• /
• 2020

Scaffolding works are demolished after this structure is completed, and safety accidents often occur because they are installed differently from legal standards or frequently change during work. Therefore, in order to strengthen the safety of scaffolding, the Ministry of Land, Infrastructure and Transport required a need for design standards for temporary facilities that can systematically prevent and solve large-scale safety accidents that are repeatedly increasing during temporary construction. It has been enacted, and some contents have been revised for the past three years. However, construction site personnel do not know or know the revised matters, but often install scaffolding by the installer's experience rather than complying with relevant laws and regulations. It is the situation that the ground strength test of the foundation ground for the load applied to the floor of the column is omitted in most sites. Therefore, this study grasped the actual situation on the degree of recognition of the revised laws and regulations of the construction site and the foundation-based treatment of the floor working load of the scaffolding column, and derived problems. In addition, we intend to provide reference materials for the endurance test according to the ground conditions to small-scale small sites where it is difficult to conduct the test by carrying out the endurance test of the scaffolding ground according to the revised standards.

• 물과 미래
• /
• 제24권1호
• /
• pp.63-71
• /
• 1991

본 연구는 터널식 소수력 발전소의 타당성 검토 기법에 관한 것으로 개발 후보지의 유량지속곡선을 작성하기 위해서 Weibull분포의 누적밀도함수와 Thiessen법을 채택하였고, 터널식 소수력 발전소의 성능예측 모델과 건설비 산정 모델이 개발되었다. 또한 한강 수계에 산재한 8개소의 개발후보지를 선정, 실측하여 이들을 대상으로 성능 특성 및 경제적 타당성을 분석하였다. 분석 결과, 터널식 소수력 발전소의 경우 발전단가를 가장 낮게 하여 주는 최적 설계유량은 유량지속곡선상의 시간비가 20%에서 30%사이에 해당하는 유량이라는 것이 밝혀졌다. 또한 개발 후보지의 설계유량, 유효낙차, 설비용량, 년평균 가동율, 년간 전기 생산량 등과 같은 초기설계제원이 산정되었다.

• 대한안전경영과학회:학술대회논문집
• /
• 대한안전경영과학회 2010년도 추계학술대회
• /
• pp.81-91
• /
• 2010

Daily workers in construction sites rarely receive the benefit of systematic safety and health training as they are required to move from one construction site to another in response to the start, completion, and repetition of construction works. Also, small- to medium-sized construction sites often lack the capacity to train their workers. Therefore, as in the advanced countries, basic safety training system for construction workers should be conducted in the industrial-level, rather than in individual workplace-level, to make the training more effective. By doing so, only workers with the basic safety training will be able to engage in construction works. Consequently, accidents in the construction industry will decrease, as workers themselves who are at the forefront of the construction worksites are empowered to play the central role in accident prevention activities.

• 한국산업안전학회:학술대회논문집
• /
• 한국안전학회 1998년도 춘계 학술논문발표회 논문집
• /
• pp.207-214
• /
• 1998

In the past several years, accident frequency rate was decreased but severity rate was increased at construction sites with less than two-hundred workers. Accidents caused by failure of education in respect with the management occupied about 40 % in 1997. In this research, a questionnaire survey to know the effects of safety education was committed for small & medium construction sites. Survey results showed that workers wanted to improve work environments and safety facilities than safety education, however they also were not satisfied to educational facilities, contents and methods. Whereas, they agreed that they improved safety consciousness after safety education. As a result, four appropriate methods to promote effective safety education were proposed.

• 한국주거학회논문집
• /
• 제11권4호
• /
• pp.53-63
• /
• 2000

The study focuses on the problems of store space supply in apartment sites and suggests policy directions for the problem. Based on the results of field survey and site reconnaissance, this study identifies following problems and policy directions. First, the stores do not meet consumers various demand due to item limitations with small size. Consequently, there are many closed and/or unsold stores with high vacancy rates, Second, there is a tendency that the closed store rate becomes higher as apartment size becomes smaller. We suggest some law and regulation amendment that make store supply optional rather than mandatory in the case of small apartment site construction.

• International Journal of Internet, Broadcasting and Communication
• /
• 제11권1호
• /
• pp.27-38
• /
• 2019

Sensors collect information for Internet of Things (IoT)-based services. However, indoor construction sites have a poor communication environment and many interfering elements that make it difficult to collect sensor information. In this study, a network was constructed between a Bluetooth Low Energy (BLE)-based IoT device based on a serverless IoT framework and a router. This experimental environment was applied to large- and small-scale indoor construction sites. Experiments were performed to test the communication performance of BLE-based IoT devices and routers at indoor construction sites. An analysis of the received signal strength indication (RSSI) graph patterns collected from the communication between the BLE-based IoT devices and routers for different testbed site situation revealed areas with good communication performance and poor communication performance due to interfering factors. The results confirmed that structural components of the building as well as the materials, equipment, and temporary facilities used in indoor construction interfere with the communication performance. Construction project managers will require improved technical knowledge of IoT, such as optimizing the router placement and matching communication between the router and workers, to improve the communication performance for large-scale indoor construction.

• 한국방재안전학회논문집
• /
• 제14권3호
• /
• pp.39-49
• /
• 2021

고용노동부가 최근 발표한 '2020년 12월 말 산업재해 현황'에 따르면 산업별로 산업재해 대상이 되고 있다. 건설업별 사고사망자 수, 사고유형별 사고사망자 수, 사업장 규모별 사고사망자 수는 5~49명으로 소규모 건설현장에서 추락사고가 대부분 발생한 것으로 나타났다. 따라서 도시형 생활주택은 소규모 건설현장으로 낙상사고 발생 확률이 매우 높다. 재해 발생을 위한 가을 모의훈련은 공공부문의 대형 건설 발주기관 위주로 실시되며 소규모 건설현장에서 주택건설업체가 실시하는 것은 국내 최초다. 본 연구는 도시생활주택의 정의, 시공특성, 안전관리 실태 등을 분석·제시하고 추락사고 발생시 긴급구호절차 매뉴얼을 개발·확산하여 사망을 최소화하였다.

• 한국융합학회논문지
• /
• 제10권7호
• /
• pp.175-182
• /
• 2019

본 연구는 기계학습 기법 중 토픽 모델링을 활용하여 건설현장에서 발생하는 추락재해에 대한 토픽을 분류하고 각 토픽에 따른 재해요인을 분석하였다. 잠재 디리클레 할당 기반의 토픽 모델링을 적용하기 위해 텍스트 데이터의 전처리를 하였고 Perplexity 점수로 평가하여 모형의 신뢰성을 높였다. 각 토픽에서 공통으로 도출된 추락재해의 대부분은 소규모 사업장에 속한 일용직 작업자들에게 발생하였다. 추락재해의 대부분의 원인은 안전장비 미착용, 현장 정리 정돈 미흡, 안전장비의 성능 및 착용 상태로 인해 제대로 작동하지 않은 것으로 판단되었다. 추락재해를 예방하고 절감하기 위해서는 소규모 사업장에 맞는 안전교육과 작업장의 정리 정돈과 개인 안전장비의 적절한 착용 상태 및 성능을 확인하는 것이 중요한 것으로 도출되었다.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2020년도 가을 학술논문 발표대회
• /
• pp.67-68
• /
• 2020

Real-time information on the construction project required by the owner make the project's transparency and overall productivity will be improved. This study analyzes domestic and foreign patents for construction project management to identify trends in technology development, construct cloud-based construction project management system solution UI, and proposes functions and services for each module. Trend research is conducted through patent search, and the analysis is divided into quantitative analysis which means quantitative statistics and qualitative analysis which means the technical contents of each patent. The construction project management system solution is based on smart devices at small and medium-sized sites, allowing both the owner and the construction personnel to share information.