This study analyzed the major change of revised Construction Technology Promotion Act in the field of safety management. In order to increase the execution of the system of construction safety management, Construction Technology Promotion Act was revised at the end of 2018. The key issues were founded in the system of safety management plan, regular safety inspection by external professional organization, and irregular safety inspection by clients. By revised law, the role and responsibility of construction clients was enforced and the clients were recognized as leading participants in construction safety management.

Construction safety is one of the significant problems on the world. Deep learning is an emerging term that acquires, processes and analyses image or video data to help computers have a high-level visual understanding of the world. In recent years, it has been introduced into the construction industry for improvements of occupational health and safety. This research contributes in solving this problem by using deep learning only RGB images that output detects the hazard zone on construction sites. The main goal of this study is to use different computer vision and deep learning to develop for different cases concerning fall related hazards.

최근 산업 활동에 의해 발생하는 CO2에 대한 처리와 산업부산물에 대한 유효처리 및 자원화 방안이 시급히 요구되고 있다. 본 연구는 콘크리트 혼합재료로 활용이 가능한 산업부산물를 대상으로 탄산화 양생에 의한 건설재료로의 적용성 평가를 목적으로 한다. 이러한 목적을 위해 연구용 시멘트(research cement, RC), 고로슬래그 미분말(GGBFS) 및 유동층 보일러 애시(CFBC)를 대상으로 탄산화 양생에 의한 물리·화학적 변화를 비교 검토하였다. 페이스트 내부의 미세조직 변화를 살펴보기 위해 XRD, SEM 분석을 수행하였다. 실험결과 탄산화 양생을 통해 생성된 반응 생성물인 탄산칼슘은 페이스트 내부의 공간을 채우며 밀도가 높은 미세 구조를 형성함을 확인하였다. 또한, CO2 양생시간이 길어짐에 따라 탄산칼슘 결정이 함께 성장하여 밀실한 미세구조를 이루는 것을 확인하였다.

This paper presents the mechanical response of concrete composites subject to extreme loadings including blast. In general, the dynamic strength of the concrete was greater than the static strength of the concerete so the dynamic increase factor (DIF) was defined as a ratio of the dynamic strength to the static strength and greater than one. Since the DIF was a function of strain rate, it was hard to apply the DIF to the analysis and/or design of concrete. Therefore, the new

This study is aimed at developing a wireless unified-maintenance system (WUMS) that would satisfy all the requirements for a disaster preventive SHM system of civil structures. The WUMS is designed to measure diverse types of structural responses in realtime based on wireless communication, allowing users to selectively use WiFi RF band and finally working in standalone mode by means of the field-programmable gate array (FPGA) technology. To verify its performance, the following tests were performed: (i) A test to see how far communication is possible in open field, (ii) a modal test on a bridge to see how exactly characteristic real-time dynamic responses are of structures. Finally, the WUMS is proved valid as a SHM, and its outstanding performance is also proven.

Most of the companies that build small houses are mostly private businesses or small corporations. Lack of awareness of poor management environment and small-scale projects and lack of systematic management cause many losses and management difficulties in project execution. Therefore, there is a need to improve the quality of small - sized houses by identifying the difficulties and weaknesses of small - and mid - sized construction companies that build small houses, and the factors that impede the safety and housing environment of small houses. The purpose of this study is to propose an improvement plan through a questionnaire survey on small - scale housing construction specialists.

This paper developed the guideline for the safety and health(S&H) file drawn by a client in construction plan stage. According to the announcement of revised Occupational Safety Health Act(February 9, 2018), the construction client should make or manage the three S&H files in the plan, design, and work stages respectively. By analyzing S&H management systems led by the client and surveying the opinion of construction participators, the contents and practical method of the S&H file in the plan stage was proposed. Client should control hazard in construction site through the S&H file. And, it should include important S&H condition dealt with design and work stages as well as selection method of competent designer and contractors with S&H capacity.

This study investigated both leaching of heavy metals and ecological toxicity when coal bottom ash (CBA) generated by power plants has been used to reduce both erosion and turbidity of surface runoff at construction sites. The Korean leaching test (KLT) method, sequential extraction method, and acute toxicity test using Daphnia magna were performed to evaluate the environmental impacts and the ecological risks of CBA. According to the results of the KLT method of CBA, trace amounts of Cu were leached at limit of quantitation whereas metal leaching was not monitored for other heavy metals. Through the sequential extraction method of CBA, the relatively high leaching potential was found for As and Pb due to greater fraction of exchangeable (F1) and bound to carbonates (F2), and reasonable probability of leaching under the reducing/anaerobic environment was expected for Cu due to high faction of bound to Fe?Mn oxides (F3). However, significantly low probability of leaching was expected for Cd, Cr, Ni, and Zn with grater fractions of bound to organic matter (F4) and residual (F5). Additionally, total amount of heavy metals in CBA was lower than criteria for soil pollution concerns, and were similar or slightly lower levels than the ‘15 National soil average concentration excluding Cr6+. Finally, acute toxicity test using Daphnia magna display no impact for mobilization and lethality in either the prefiltration or post-filtration experiment, indicating that the ecological toxicity was insignificant with zero values of toxic unit. Consequently, no environmental impacts or ecological toxicity are expected when CBA generated by power plants has been used to reduce both erosion and turbidity of surface runoff at construction sites.

The purpose of this study is to measure the cost-benefit of a road construction project in Vietnam through international development cooperation, which includes private grants and Official Development Assistance(ODA). In developing countries, it is difficult and costly to use data on markets, the CVM(Contingent Valuation Method) to measure the WTP(Willingness-to-Pay) as the benefits of road construction are used. A total of 232 villagers in 16 villages of Lao Cai Province in Northern Vietnam have been surveyed. It is found that the Benefit-Cost Ratio(B/C) in all 3 models are found to be well over 1.0, ranging from 2.8 to 3.64 with the discount rate of 0.06. These BC ratios imply the road construction project in Lao Cai can be justified. Also, it is found that the shortened travel time is the most relevant factor for WTP among direct benefits and the enhanced academic achievement of the children is the most relevant factor among indirect benefits, due to easier and faster access to schools, which in turn increase the school attendance rate. The result of this study can be used to justify other similar projects in Vietnam, even though the benefits may have to be reassessed in other countries.

This study assesses greenhouse gas evolution from construction-material manufacturing facilities and estimates the potential reduction of these gases via the future massive sequestration of carbon dioxide. The scope of the evaluation specifically targets the global-warming potential in terms of kg-CO2 equivalent/tonnage industrial waste. Life cycle assessment (LCA) is a method to quantitatively analyze the input and output of a specific material resource during its life cycle from raw-material acquisition to final disposal as well as its environmental effect(s). LCA comprises four steps: its objective and definition of the scope, the entire life-cycle analysis list, an evaluation of its effects, and life-cycle analysis. The annual inflow of petro-ash reaches 300,000 tons, and this material is transported via screw-driving systems. The composition of the petro-ash is 1.2% volatile compounds, 6.8% fixed carbon and 92% ash contents. A total of 38,181,891 Nm3/yr of carbon dioxide is sequestrated, which is equivalent to 75,000 tons per annum and 304.5 kg/ton of petro-ash waste, with 250 kg/ton of the latter sequestrated as calcium carbonate. The final analysis on the effect of one ton of petro ash in construction materials showed 27.6 kg-CO2 eq emission. According to the final LCA analysis, only 27.6 kg-CO2 eq/ton was emitted by the petro-ash that was used in construction materials if CO2 fixation during carbonate mineralization was considered, where -250 kg-CO2 eq/ton positively contributed to the LCA. In the future, commercial-scale process modification via the realization of continuous processes and the more efficient reduction of carbon dioxide is anticipated.

This paper investigates the safety and health role processes that the client should perform at each phase of the construction project. Since the client is one of the top decision makers in the whole construction project, the client should give roles and responsibilities for safety and health of workers. Advanced system of occupational safety and health management led by the client was analyzed in order to actively participate in occupational accident prevention activities according to the client’s authority. The role of the client in the overall construction work such as planning, design and construction process was derived.

The purpose of the study is how to educate construction IT convergence for BIM engineers. With the advent of the fourth industry in recent years, BIM has attracted much attention in the construction industry. However, There are not many Construction-IT experts who can link the 4th industry with BIM. There is an increasing demand for construction IT convergence education that connects the 4th industry and BIM. How should we design construction IT convergence training for construction engineers? We surveyed 38 BIM engineers and 88 construction professionals in order to find a direction for construction IT convergence education for BIM engineers.

According to this study, small-scale construction projects with a construction value of less than 300 million won are placed in the blind spot of safety management inspection. Therefore, it is necessary to improve the management and inspection system that reflects characteristics of small-scale construction sites.

The purpose of this study is to provide client safety and health management duty in the construction industry. Most regulations did not give direct roles and duty to client in construction industry. As a result of the survey on construction workers who have the greatest influence on the prevention of industrial accidents, the clients and constructors chose contractor the most. Safety managers and supervisors chose client the most. Therefore, it is necessary to manage safety and health centered on the client in order to prevent fundamental disasters.

This paper propose to make a Construction site safety management system using beacon indoor positioning technology. in this system, as using beacon, it can measure the position of worker who have smartphone or any device which have bluetooth function. there is two way to use technology of beacon, first one is distance technology which can alarm dangerous situation such as appoaching heavy equipment. second one is location positioning technology. it is the main technology which can measure the position of workers in real time. this system is based on low energy and accurate sensor, beacon, and have a low cost advantage. so it is expected to improve safety on the construction site.

본 연구는 음의 포아송비 거동을 가지는 격자체의 구조부재 보강재로의 적용이 가능한지에 대한 검토를 수행하였다. 콘크리트를 포함한 일반적인 재료는 외부 하중의 작용 시 양의 포아송비 거동을 가진다. 이러한 콘크리트의 역학적 거동을 음의 포아송비 특성을 가지는 금 속 격자체가 구속함으로써 콘크리트의 강성을 증대시킬 수 있음을 이론적으로 확인하였다. 또한 실제 건설산업에 적용이 가능한 수준의 음의 포아송비 거동을 가지는 격자체의 형식을 제시, 역학적 거동 특성을 수치 해석적으로 검토하였다.

국내 태양광 시장은 정부의 주도하에 2006년 이후 연평균 50% 이상의 성장률을 보이며 급성장 하였다. 2006년에 22MW였던 태양광 시장은 2012년, 그보다 10배 이상인 279MW의 규모에 이르렀고 2013년에는 330MW가 설치되었다. 그 결과 2006년 36MW에 불과하였던 국내 태양광 누적 설치용량은 6년만인 2012년에 1GW를 돌파하였다. 기존 연구결과를 통해 유추한 결과 폐 태양광 모듈의 발생 시기는 태양광 모듈 수명이 2000년 이전의 생산제품은 10년, 2001년∼2010까지의 생산제품은 15년, 2011년 이후의 생산제품에 대해서는 20년이라고 가정할 때에 대략 2020년 정도가 될 것으로 추측된다. 생산과정에서 발생한 폐 모듈은 물론 기존에 설치된 모듈의 효율저하, 제조시의 불량 및 새로이 개발된 고효율(발전효율 18%이상)패널로의 교체로 모듈의 평균수명이 낮아져 매년 폐기되는 모듈의 양은 기하급수적으로 증가할 것으로 예상된다. 현재까지 처리된 폐 모듈의 양도 최소 5MW으로 추측되며, 2020년부터 처리해야 할 폐 모듈의 양은 백MW단위로, 많은 양의 폐기물이 배출될 것이라 본다. 아직까지 우리나라는 자원 재생에 대한 인식이 부족하여 여러 가지 문제에 당면해 있는 실정이다. 우리나라는 전국적인 회수 체계가 미흡하고 재활용 인식이 낮아 수거자체가 어려울 뿐만 아니라, 도시 광산은 서비스업으로 분류되어 있어 산업단지 내 공장설립이 제한되어 있고, 그 절차 또한 복잡하고 오랜 시간 기다려야하기 때문에 접근이 쉽지 않다. 이에 본 연구는 폐 PV모듈(Photovoltaic module)에서 추출한 저 철분 강화유리 분말을 이용한 콘크리트용 혼화재로서의 활용가능성 알아보고, 최근 환경문제로 대두되어 있는 산업폐기물의 건설 순환자원으로의 재활용방안을 제시하고자 함이 목적이다.