This study aims to evaluate traffic safety facilities in school zones in Busan Metropolitan City through Importance-Performance Analysis. This study investigated the traffic safety facilities in nine school zones, which have relatively more traffic accidents in Busan Metropolitan City from 2020 to 2022, through a field study and an Analytic Hierarchy Process(AHP). It identified their performance(i.e., compliance rate) and importance to derive measures for the improvement of traffic safety facilities in school zones. The field study showed that the compliance rate of starting points among traffic safety signs was low, and no speed limits were complied with the installation regulations among traffic road markings, but road safety facilities were generally well managed and operated. As a result of AHP, the order of importance was road safety facilities, traffic safety signs, and traffic road markings. More specifically, speed bumps, safety signs, and crosswalks were found to be more important than others in road safety facilities, traffic safety signs, and traffic road markings, respectively. Importance- Performance(compliance) Analysis revealed that the traffic safety facilities necessary to be most urgently improved are starting points. This result can be resorted to underlying measures to determine priorities for installing and operating traffic safety facilities in school zones.

국내에서 겨울철 발생하는 결빙사고는 전체적인 교통사고 대비 치사율이 1.7배 높은 것으로 나타났다. 주행속도가 높은 고속국도의 경우 결빙사고 치사율은 18.7로, 결빙 외 고속국도 교통사고 치사율인 4.2와 비교하여 약 4.5배 높았다(KoROAD, 2024). 특히 교량과 터널과 같은 도로시설물은 구조적 특성과 환경적 요인으로 인해 결빙 형성에 매우 취약하다. 교량은 지면으로부터의 열전달이 차단되 기 때문에 겨울철 노면온도가 낮아 결빙이 형성될 가능성이 높으며, 터널은 겨울철 낮은 온도와 터널 입출구부의 응달지역 형성 및 터널 내부와 외부 공기로 인한 급격한 온도변화로 인해 결빙이 발생할 가능성이 높다. 또한, 도로시설물은 교통사고 발생 시 치사율이 높게 나타나는 경향이 있다. 실제로 교량과 터널에서 발생한 교통사고의 치사율은 전체 1.94, 터널 5.05, 교량 4.10으로 도로시설물에서 발생한 교통사고의 치사율이 높았다(KoROAD and ACCRC, 2017). 따라서 도로시설물에서 발생하는 결빙사고는 쉽게 결빙이 형성되 는 환경조건과 사고 발생 시 치사율이 높은 특성으로 인해 일반 도로보다 높은 위험성을 내포하고 있다. 그러나 현재로써 도로시설물 에서 발생하는 결빙사고의 원인과 위험성을 중점적으로 분석한 연구는 그 수가 부족하며, 기존 연구들은 결빙 구간의 기후적 특성이 나 개별 결빙사고 사례 분석에 국한되어 있어 도로시설물은 결빙사고 분석 시 여러 가지 환경요인 중 하나로서만 고려되고 있는 실정 이다. 본 연구에서는 도로시설물에서의 결빙사고 위험도를 평가하는 방법을 제시하고, 이를 Min-Max(최소-최대) 정규화 과정을 통해 구체 화함으로써 보다 체계적인 분석이 가능하도록 한다. 이를 통해 도로시설물의 겨울철 운영에 있어 효과적인 결빙사고 방지 대책을 수 립하는 데 기여하고자 한다.

PURPOSES : The purpose of this study was to quantitatively evaluate the variability of LiDAR performance indicators, such as intensity and Number of Point Cloud(NPC), according to various environmental factors and material characteristics. METHODS : To consider the material characteristics of road safety facilities, various materials (Reference Material(RM), reflective sheet, matte sheet, granite, plastic, and rubber) were used in a darkroom, and the performance indicators of LiDAR were repeatedly measured in terms of changes in the measurement distance, rainfall, and angle of observation. RESULTS : In the case of standard reflective materials, the intensity measurement value decreased as the measurement distance and rainfall increased. The NPC showed a tendency to decrease as the measurement distance increased, regardless of rainfall intensity. For materials with high-intensity values, it was found that rainfall intensity and color had negligible effect on the change in intensity compared with the measurement distance. However, for materials with low-intensity values, it was found that the measurement distance, rainfall intensity, and color all had a significant effect on the change in intensity. CONCLUSIONS : For materials with high-intensity values, it was found that rainfall and color had negligible effect on change in intensity compared with the measurement distance. However, for materials with low-intensity values, the measurement distance, rainfall, and color all had a significant effect on the change in intensity value.

PURPOSES : Experimental findings pertaining to the mechanical properties of calcium aluminate cement (CAC)-based repair mortars incorporated with anhydrite gypsum (AG) are described herein. METHODS : To prepare the mortars, three different levels of AG were adopted and the ratio of water–cementitious materials was fixed at 0.50. For comparison, mortar composed of ordinary Portland cement was prepared. The fluidity, setting time, compressive and bond strengths, absorption and surface electric resistivity of the mortars were measured at predetermined periods. RESULTS : The incorporation of AG increases the fluidity but decreases the setting time of the CAC-based repair material system. However, the AG in the CAC mixes does not effectively enhance the compressive strength of the mortars owing to the decreased formation of CA hydrates, such as CAH10 and C2AH8. Meanwhile, the mortar with 10% AG shows excellence absorption. CONCLUSIONS : The mechanical properties of CAC based-mortars rely significantly on the amount of AG incorporated. However, further studies regarding the microstructure and durability of CAC-AG repair mortars must be conducted to obtain the optimal mixture.

PURPOSES: This study aims to evaluate the resistance to chemical attack of combined organic and inorganic hybrid mortars as the repair materials (i.e., HRM mortar) used for concrete road facilities through a comparison with mortars made from cement repair materials (i.e., IRM mortar). METHODS: Inorganic materials used as a binder and two mineral fillers were adopted to produce HRM mortars. The ratio of the main resin versus the hardener was fixed at 2:1. For comparison, IRM mortars made of cement repair materials were also manufactured. The mortars were exposed to chemical solutions, such as NaCl, MgSO4, Na2SO4, and H2SO4, with the same concentration of 5% after 7 days of curing. The compressive strength, compressive strength loss, mass ratio, and relative bulk density of the mortar samples exposed to the chemical solutions were measured at predetermined periods. In addition, a scanning electron microscope observation was performed to evaluate the microstructures and the products formed by the chemical reaction of the mortar samples. RESULTS : As a result, the resistance to chemical attack of the HRM mortars was found to be much better than that of the IRM mortars, regardless of the types of attacking sources. This finding implies that HRM is a highly promising and versatile material because of its excellent resistance to chemical attack. CONCLUSIONS: The application of the combined organic and inorganic hybrid mortars is a possible option for repair of concrete road facilities exposed to aggressive environments.

도로 교량 시설물은 그동안 인적, 물적 자원의 이동을 원활하게 하여 지역 균형 발전을 도모할 뿐만 아니라, 생산성 증대에 기여함으로써 국가 발전의 토대가 되어왔다. 최근 시간이 지남에 따라, 사회기반 시설물의 노후화가 진행되고 있으며, 지속적 유지·관리를 통해 사회적 자산인 시설물 유지에 대한 필요성이 더욱 증대되었다. 도로교량 시설물의 점검 및 평가체계는 시설물의 현재의 상태를 정확히 진단하고, 시설물을 이용에 있어서 필요한 성능들의 만족 여부를 면밀히 평가할 수 있도록 해야한다. 이로써, 교통 인프라 시설을 유지관리하는데 필요한 합리적인 의사결정이 가능하다. 본 연구에서는 중소 도로 교량의 성능평가 도입을 위한 기초 연구를 위하여, 국내외 도로 교량 시설물의 점검 및 평가체계 비 교·분석 연구를 수행하였다. 기존 국내 도로 교량 시설물의 정기점검 및 정밀안전진단에서의 점검 항목 및 평가방식, 국내 제1 종 및 제2종 시설물 종합성능평가에서의 평가항목 및 체계 분석과, 제3종 시설물 안전등급 평가 매뉴얼의 평가항목 및 체계에 대한 대응 분석을 수행하였다. 또한, 국외 교량 점검 및 평가 매뉴얼을 분석을 통해, 국내 도로 교량 시설물의 점검 및 평가체 계와의 비교·분석 검토 연구를 수행하였다.

PURPOSES: The objective of this study is to evaluate the durable performance of combined organic and inorganic hybrid mortar as repair material (HRM mortar) for concrete road facilities via comparison with that of cement repair materials (IRM mortar). METHODS : To produce HRM mortars, inorganic materials as binder and 2 mineral fillers were adopted. The ratio of main resin versus hardener was fixed at 1:2. For comparison, IRM mortars made with cement repair materials were also manufactured. Compressive, flexural, and bonding strengths were measured at predetermined periods. For durability assessment, the scaling resistance, freezing & thawing resistance, rapid chloride penetration resistance, and acid attack resistance of those mortars were experimentally monitored. RESULTS: The durability performances of HRM mortars, especially with respect to freezing & thawing, rapid chloride penetration and acid attack, were identified to be much better than those of IRM mortars. This result implies that HRM is a highly promising and versatile material because of its excellent durability. CONCLUSIONS: It is concluded that the application of the combined organic and inorganic hybrid mortars is possibly an option for the repair of concrete road facilities exposed to aggressive environments.

PURPOSES : The objective of this study is to evaluate the performance of combined organic and inorganic hybrid mortar used as repair materials (UM mortar) for concrete road facilities by comparison with cement repair materials (RM mortar). METHODS: In order to produce UM mortar, four different levels of inorganic materials were adopted and the ratio of main resin to hardener was fixed at 1:2. For comparison, RM mortar made with cement repair materials was also produced. Fluidity, strength characteristics, length change, and freezing-thawing resistance of the mortars were measured at the predetermined periods. In addition, the microstructures of the mortars was performed on the 28-day mortar samples to examine the properties of the interfacial transition zone (ITZ). RESULTS : It was observed that the mechanical properties, except for compressive strength, and freezing-thawing resistance of UM mortars were much better than those of RM mortar. Furthermore, showing a densified ITZ properties on the UM mortars from the microstructural observation, the usage of UM mortars exhibited a beneficial effect on the enhancement of mortar properties. CONCLUSIONS: It is concluded that the application of combined organic and inorganic hybrid mortars is a possible option for the repair of deteriorated concrete road facilities.

Following a 5.8 magnitude earthquake on September 12, 2016 in Gyeongju Province, a magnitude 5.4 earthquake occurred in the northern region of Pohang City on November 15, 2017 in South Korea. Only 7.9 % of the building structures are earthquake-resistant, according to the recent survey conducted by the government agencies in October 2017. In this paper, the linear analysis seismic performance evaluation procedure of the existing school structures presented in the revised methodology(Seismic Performance Evaluation Procedure and Rehabilitation Manual for School Facilities) was introduced. In this paper, the linear analysis evaluation procedure presented in the revised methodology was introduced and the seismic performance index of the example structure was evaluated using the linear analysis evaluation procedure. The seismic retrofit was verified by the linear and nonlinear dynamic analyses using Perform 3D. The analysis results show that the dissipated inelastic energy is concentrated on the retrofitted shear wall and the maximum inter-story drift of the stadium model structure with damping system satisfies the requirement of the current code.

Post-earthquake risk assessment technique in Korea is developed in 2013 by National Disaster Management Research Institute, at the same time, related manual and standard regulation is distributed to every local government by National Emergency Management Agency. The objectives of this research are to investigate and evaluate the post-earthquake risk assessment of 9.12 Earthquake (M5.8, Gyeongju City, 2016) and 11.15 Earthquake (M5.4, Pohang City, 2017). To suggest and improve the assessment process of post-earthquake risk, first post-earthquake risk assessment method of advanced foreign countries including US, New Zealand and Japan are compared, and post-earthquake evaluation activities in 9.12 Earthquake and 11.15 Earthquake are analyzed. From the results, it is needed to expand the adapted building and structure types and strengthen the earthquake disaster response capacity of local government.

‘Seismic Performance Evaluation Method for Existing Buildings (2013)’ developed in accordance with the overseas guidelines ASCE 41 - 06 is the most widely used procedure among domestic seismic performance evaluation guidelines in Korea. However, unlike ASCE 41 - 06, it stipulates that the final performance should be derived as the gravity load distribution ratio of the lateral force resistance system in the guideline. Therefore, in the case of a dual steel structure system with slender braces, where the internal moment frame is mostly responsible for the gravity load, the evaluation of slender braces based on gravity load distribution ratio is difficult to be achieved. In this research, we propose an objective evaluation process for such system by evaluating seismic performance for large-scale factory facilities as an example.

Recently, the damage caused by typhoons and strong winds frequently displayed according to world climate change tends to be increasing. In the case of soundproof / windproof wall installed on the road, frequent occurrence does function for damage due to strong wind. As a result, in this study, strong wind fragility evaluation was performed to predict the degree of damage of strong winds of soundproof / windproof walls. We were conducting research focusing on the destruction mode in which the overall destruction of the sound barrier caused by the destruction of the aluminum frame occurs. Three node bending experiments were conducting for grasping the material properties of a soundproof wall aluminum frame that is currently being constructed on a road. Based on the results of this experiment, the resistance performance of the target structure was calculated, the frame breakage was selected as the limit state, and the wind load acting on the simplified soundproof wall model was measured using the Monte Carlo model model technique to measure.From now on, through the additional study, it will be necessary to proceed with a more accurate evaluation of the safety against strong windsof the soundproof wall structure using the vulnerability evaluation execution and the setting of the limit state.This study is expected to be the basic data of the study on prediction technique of wind - induced damage of soundproofing and windshield walls in the future.

In this study, seismic fragility analysis are carried out for the water supply facilities. To consider the uncertainty of ground characteristics, the variability of soil in several cases is considered based on RSM and the winkler Foundation method is adopted to model the ground. Limit state of water supply facilities defined as two steps.: the collapse prevention level and the serviceability level. As an input ground motion for evaluating seismic fragilities, foreign surveyed real earthquakes and artificial earthquakes which can be generated in the Korean peninsula are used. The destruction ability according to peak ground acceleration of an earthquake for the water supply facility is evaluated in this paper. From the analysis results, the probability of failure of the ductile iron pipe and wrapped steel pipe under real earthquakes have shown as upper than the Korean artificial earthquakes. It could evaluate the damage of water supply facilities to an earthquake and could be applied as basic data for seismic design of water supply facilities.

본 연구에서는 농업시설물 중 내재해형 비닐하우스와 축사에 대한 화산재 취약도를 평가하였다. 이들 농업시설물에 대한 화산재 취약도를 평가하기 위해 화산재 하중의 확률밀도함수와 대상 시설물 저항성능의 확률밀도함수를 비교하는 해석적 접근법 기반의 FOSM(first-order second-moment) 방법이 이용되었다. 화산재 취약도 평가를 위하여 폭과 높이 그리고 단면 및 재료적 특성이 상이한 6종의 내재해형 비닐하우스와 표준형, 해안형, 산간형으로 구분된 3종의 축사가 사용되었다. 또한 FOSM 방법으로 평가된 내재해형 비닐하우스와 축사의 취약도는 GEV(generalized extreme value) 분포함수의 모수 형태로 최적화된 후 데이터베이스화되었다. 본 연구에서 평가한 화산재 취약도는 백두산 화산분화에 따른 화산재 퇴적에 대한 농업시설물의 위험도 평가를 위하여 활용될 수 있다.

PURPOSES : This study is to improve the highway management and rehabilitation efficiently by method for asset management. METHODS : Based on the literature review, The concept of this paper is to investigate the use of asset values from a Bridge management system to improvement of maintenance system more efficiently. This study is suggested for an evaluation method based on the current bridge condition by Written-down replacement cost of the assets. RESULTS : We suggests the optimization methodology of road asset valuation for budge distribution and performance measure. CONCLUSIONS : We evaluate all of national highway's bridge by the optimization methodology of road asset valuation, and suggest application methods of asset result.

This provided a basic frame to analyze the investment effect on the road, railroad, airport and port as a national dimension but it still has a limitation to analyze the specific economic and financial validities to consider the characteristics of the traffic facilities within the area. Conclusively, the aims of this study provide the reasonable evaluation guidelines effectively to the local automatic groups, especially Chungju in the frame of the present evaluation guidelines. We provide the adaptive alternatives on the present systems which are difficult to adapt to the present investment evaluation guidelines; the estimation method of the social economic index and the estimation method of the traffic demand. Additionally, we discuss the research method of the passage actual state for a reasonable estimation of the traffic demand. The result of this study will be activated for the validity check and construction plan of the reasonable traffic investment plan of Chungju city.