The object of this paper is to estimation of noise reduction effect of road noise by operating condition due to tire noise regulation. A prepare the countermeasure of the noise reduction according to collect tire/road noise data under various influencing factors by using the tire test method. To accomplish the object : A automotive is used as a test platform to test tire/road noise by changing different types of tires and using the On-Board Sound Intensity test system. The influence of inflation pressure, road, load, speed and pattern type on tire/road noise is compared and analyzed. At the same time, the mechanism of tire/road noise is analyzed, which provides an experimental basis for tire noise reduction.

Considering the large number of civil, commercial and investment disputes that arise between Chinese investors and their counterparts along the Belt and Road, it is necessary to establish a dispute settlement mechanism. The open, cooperative and non-institutionalized features of the Belt and Road Initiative require the reform and improvement of China’s domestic dispute settlement mechanism for foreign civil, commercial and investment disputes; and bilateral and multilateral dispute settlement mechanisms between or among China and the Belt and Road countries should be strengthened. When appropriate, China may propose the establishment of a multilateral dispute settlement mechanism that is especially designed for the Initiative. The status quo of dispute settlement mechanisms between China and the Belt and Road countries necessitates the establishment of a preset mechanism that uses arbitration as the primary approach, litigation as the secondary approach, and mediation as an alternative.

PURPOSES : With the recent change to domestic and overseas construction technologies, which led to the adoption and application of threedimensional building information management (BIM), a BIM output delivery operation system is needed for the civil engineering infrastructure category. This study analyzes the domestic and overseas BIM-order placement, BIM-related guidelines/guides, and the BIM output delivery system for the road construction project category to present guideline development measures for BIM output writing and delivery. METHODS: This study surveys and analyzes the domestic BIM-related research trends to examine the domestic-infrastructure BIM-order placement situations in public ordering agencies. Additionally, it analyzes the domestic BIM-related guides and guidelines and existing twodimensional electronic delivery systems and the domestic and overseas BIM output delivery systems. This study defines the guideline composition system and direction to present criteria for BIM output writing, delivery, management, and utilization in the road category. Furthermore, it presents guideline composition measures for BIM output writing and delivery to propose detailed criteria, output-list composition, and output inspection procedures. RESULTS : This study presented BIM output guideline development measures for planning BIM output writing and delivery and management/utilization measures in the road category. To that end, it determined the domestic and overseas BIM guide and guideline composition systems, BIM ordering criteria, BIM data writing and delivery criteria, BIM output management and utilization measures, and a common BIM output list to present suitable detailed criteria. CONCLUSIONS: This study sought to respond to changes to the domestic and overseas construction environment and to present output writing/delivery guidelines as activation measures supporting the adoption and application of BIM. To that end, we analyzed the domestic and overseas BIM guidelines and guides, task instructions, bid information, etc. to define the appropriate composition system and to give it direction. We defined the contents of tables and detailed descriptions to present guideline development measures for BIM output writing/delivery guidelines in the road category. This is expected to improve work efficiency for BIM and to enhance output quality and utilization. Furthermore, the adoption of BIM in the road category will provide an infrastructure environment with which to exchange BIM information with related agencies. We plant to further develop verification tools for the Ministry of Land, Infrastructure, and Transport's BIM model projects, for their output writing and delivery, and for an integrated BIM platform that will continue to improve the proposed criteria.

PURPOSES : Exposed aggregate concrete pavements have been adopted in several countries because of their advantages of pavement texture characteristics, which can produce low tire-pavement noise and higher load-carrying capacities. The magnitude of tire-pavement noise greatly depends on the wavelength of pavement texture. The wavelength of exposed aggregate concrete pavement can be controlled with maximum sizing and by controlling the amount of coarse aggregates in the concrete mixture. In this study, the maximum size and the amount of coarse aggregate in the exposed aggregate concrete pavement are investigated to produce equal levels of wavelength in the asphalt pavement. METHODS: A simple method to measure the average wavelength of pavement texture is introduced. Subsequently, the average wavelength of typical asphalt pavement is investigated. A set of mixture designs of exposed aggregate concrete with three maximum-sized coarse aggregates, and three amounts of coarse aggregate are used. The average wavelengths are measured to find the mixture design needed to produce equal levels of wavelength as typical asphalt pavement. RESULTS : With a cement content of 420 kg/m3 and fine aggregate modulus of 30%, the number of exposed aggregates was 48, and the shortest texture depth provided a wavelength of 4.2 mm. According to the number of exposed aggregates, the exposed aggregate concrete pavement could be rendered low-noise, because its wavelength was similar to that of asphalt pavement ranging from 3.9 to 4.4 mm. CONCLUSIONS : Selection of appropriate maximum sizes and the amount of coarse aggregates for exposed aggregate concrete pavement can produce a wavelength texture closely resembling that of asphalt pavement. Therefore, the noise level of exposed aggregate concrete pavement can be reduced with an appropriate maximum size and the amount of coarse aggregates are employed.

PURPOSES: The objective of this study is to evaluate road subsidence based on model chamber tests. METHODS : A theoretical review of road subsidence mechanisms was carried out, and a series of soil chamber tests with initial cavities were conducted under various conditions. Road subsidence risk was analyzed based on these results. RESULTS: The cavity collapse risk was affected by multiple factors, including cavity location, traffic loading, and asphalt layer thickness. The Nf number of loading required to reach cavity collapse increased as the cavity width increased, cavity depth decreased, and asphalt layer thickness increased. CONCLUSIONS: The effects of asphalt thickness on the risk of road subsidence was assessed to have an additional 1.5-fold effect on the subgrade thickness. This study proposed an effective cavity depth (Deff), considering the strength of the asphalt layer. Based on the results of the model chamber test, a four-class road subsidence risk model was proposed with effective cavity depths and widths. It was found that the risk of road subsidence increased as the cavity width increased and the effective cavity depth decreased. This trend is also well matched to the road subsidence risk models of Japan and Seoul.

PURPOSES: The purpose of this study is to identify the mechanism of road subsidence caused by damaged water and sewer pipes. METHODS: A series of soil chamber test using damaged water and sewer pipe models were conducted under various conditions. RESULTS : Characteristics of cavity expansion and collapse caused by damaged pipes were affected by the damaged location in the sewer pipe, the head on the water pipe, the distance between the damaged water pipe and outlet, and relative soil density. CONCLUSIONS: Sewer-pipe damage was considered a direct cause of road subsidence, and the cavity expanded discontinuously. When the outlet was located under the damaged water pipe, the cavity expanded in the water pipe’s direction, and collapse occurred above the pipe. However, when the outlet was located atop the damaged water pipe, the cavity expanded toward the outlet direction and resulted in a subsidence. Cavity expansion speed was affected by various conditions, such as the pipe’s water head, outlet position, distance between the damaged water pipe and outlet, and relative soil density. However, the cavity expansion shape did not affect factors, except for outlet position.

This paper considers the problem of scheduling loading and unloading operations of a crane in a railway terminal motivated from rail-road container transshipment operations at Uiwang Inland Container Depot (ICD). Unlike previous studies only considering the total handling time of containers, this paper considers a bi-criteria objective of minimizing the weighted sum of the total handling time and tenant service time. The tenant service time is an important criterion in terms of terminal tenants who are private logistics companies in charge of moving containers from/to the terminal using their trucks. In the rail-road container shipment yard, the tenant service time of a tenant can be defined by a time difference between beginning and finishing loading and unloading operations of a crane. Thus, finding a set of sequences and time of the crane operations becomes a crucial decision issue in the problem. The problem is formulated as a nonlinear program which is improved by linearizing a nonlinear constraint in the model. This paper develops a genetic algorithm to solve the problem and performs a case study on the Uiwang ICD terminal. Computational experiment results show that the genetic algorithm shows better performance than commercial optimization solvers. Operational implications in terms of tenants are drawn through sensitivity analyses.

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.

PURPOSES: The purpose of this study is to compare the advantages and disadvantages of 3D multichannel ground penetrating radar (GPR) equipment, which is mainly used for road cavity detection. The optimal signal analysis method was also proposed for 3D GPR data. METHODS: Four types of 3D GPR equipment were used to detect road cavities in a pilot road section in Seoul. The obtained GPR signals were evaluated in the time and frequency domain using raw data. In addition, various types of filters were applied to time domain (B-scan) data to examine the optimal signal processing. RESULTS: The time and frequency domain analysis of raw data showed that all the equipment produced reverse and strong signal reflections owing to the low dielectric permittivity of air in the cavity compared with neighbor materials. Also, the asymmetric parabolic curve was observed as well. The optimal signal processing method was determined to detect road cavities: zero-setting and background removal should be applied to all equipment. Bandpass filtering can be optionally applied to remove high-frequency noise or direct waves. CONCLUSIONS: Despite the different specifications of GPR equipment in terms of signal generation and bandwidth, the GPR signals were appropriate in terms of zero-setting, noise level, and depth of investigation. Therefore, all the multichannel GPR devices evaluated were found to be suitable to detect road cavities located at depths of 1.0 and 1.5 m after the application of proper filtering process.

PURPOSES: This paper develops a new stochastic approach to analyze the pavement-vehicle interaction model with a certain roughness and elasticity for the pavement foundation, thereby accommodating the deflection of the pavement, and to identify the road subsidence zone represented with a sudden changes in the elasticity of the foundation. METHODS: In the proposed model, a quarter-car model was combined with a filtered white noise model of road roughness and a two-layer foundation (Euler-Bernoulli beam for the top surface and Winkler foundation to represent the sub-structure soil). An augmented state-space model for the subsystems was formulated. Then, because the input is White noise and the system is represented as a single system, the Lyapunov equation governing the covariance of the system’s response was solved to obtain a structurally weak zone index (WZI). RESULTS: The results showed that the WZI from the pavement-vehicle interaction model is sensitive enough to identify road subsidence. In particular, the WZI rapidly changed with a small change in foundation elasticity, indicating that the model has the potential to detect road subsidence in the early stage. CONCLUSIONS: Beacause of the simplicity of the calculation, the proposed approach has potential applications in managing road conditions while a vehicle travels along the road and detecting road subsidence using a device with an on-board computational capability, such as a smart phone.

PURPOSES: This study aimed to evaluate the performance of a model developed for road surface temperature change pattern in reflecting specific road characteristics. Three types of road sections were considered, namely, basic, tunnel, and soundproof tunnel. METHODS: A thermal mapping system was employed to collect actual road surface temperature and locational data of the survey vehicle. Data collection was conducted 12 times from 05:30 am to 06:30 am on the test route, which is an uninterrupted flow facility. A total of 9010 road surface temperature data were collected, and half of these were selected based on a random selection process. The other half was used to evaluate the performance of the model. The model used herein is based on machine learning algorithms. The mean absolute error (MAE) was used to evaluate the accuracy of the estimation performance of the model. RESULTS: The MAE was calculated to determine the difference between the estimated and the actual road surface temperature. A MAE of 0.48℃ was generated for the overall test route. The basic section obtained the smallest error whereas that of the tunnel was relatively high. CONCLUSIONS: The road surface temperature change is closely related to the air temperature. The process of data pre-processing is very important to improve the estimation accuracy of the model. Lastly, it was difficult to determine the influence of the data collection date on the estimation of the road surface temperature change pattern due to the same weather conditions.

PURPOSES : The purpose of this study was to investigate the behaviors of the middle slab in a double-deck road tunnel subjected to construction equipment loading from such as a concrete pump car, concrete transmixer, and lifting crane. METHODS: The major construction processes of a middle slab include concrete placement, concrete transportation, and lifting of materials near the emergency passageway section. During the concrete placement, the middle slab is subjected to construction loading due to the presence of the concrete pump car and fully loaded concrete transmixer. During the concrete transportation, the middle slab is subjected to loadings from both the fully loaded and empty concrete transmixer. The emergency passageway section of the middle slab is subjected to crane loading during lifting work. The magnitudes and geometries of these construction loadings are determined and the stresses and deflections of the middle slab under these loadings are analyzed using finite element models of the middle slab. The behaviors of the middle slab under the design truck loadings are also analyzed to compare the results with those under construction loadings. RESULTS : The stresses and deflections of the middle slab under construction loadings are comparable to those under the design truck loadings. Higher stresses can be observed when the concrete transmixers cross paths at the expansion joint section of the middle slab. The behaviors of the middle slab under the construction loadings during concrete placement are very similar regardless of the section types of the middle slab such as the normal, expansion joint, and emergency passageway sections. CONCLUSIONS : When the middle slab is designed, the construction loadings should be considered to determine the primary design loads and to verify the usability of a variety of construction equipment.

여우(Vulpes vulpes)는 식육목 개과 여우속에 속하는 동물로서, 과거에는 도서 지역을 제외한 전국에 넓게 분포하였으나 밀렵, 개발, 서식지파괴 등 다양한 이유로 인해 환경부는 멸종위기야생생물 Ⅰ급의 법정보호종으로 지정하였으며, 환경부와 국립공원관리공단 종복원기술원은 2012년 부터 소백산국립공원을 중심으로 경북 영주시 일원에서 여우 종복원사업을 진행하고 있다. 여우복원사업을 성공적으로 추진하는데 가장 중요한 요소는 대상종의 서식지 환경이다. 여우의 서식지 환경에 대한 연구는 유럽이나 북미, 일본 등에서 광범위하게 연구되어져 있고 국내 연구는 미흡한 실정이다. 본 연구는 경북 영주시 일원에서 자동차 및 열차에 의해 죽은 방사 여우 5개체 지점에 대해 현장 주변 환경 조사를 하였고 5개의 좌표를 수집하여 고도, 경사, 향, 지형, 토지이용 등을 활용 하여 GIS 및 MaxEnt분석을 통해 방사 여우의 로드킬 당한 지역의 환경 특성 및 위험 잠재 지역을 파악하였다. 여우가 로드킬 당한 지점의 도로는 열차 철로 2곳, 일반 국도 1곳, 면･리간 도로 1곳, 미분류 도로 1곳인 도로 형태였고, 고도, 경사, 향, 농경지(논, 밭, 과수원)로 부터의 거리, 주거지로 부터의 거리, 수계와의 거리, 토지이용현황 등 6가지 환경 인자들을 이용하여 로드킬 발생 지역 유형을 도출 하였다. 로드킬 장소 환경 분석 결과, 평균고도 193m(150∼ 211m), 경사는 4°(0∼12.4°), 향은 남향 1곳, 서향 1곳, 나머 지는 개활지이었다. 농경지와의 거리는 평균 63m(10∼ 152.6m), 주거지와의 거리 91m(10∼215.4m), 수계와의 거리 257m(140∼545m)이었고 주변 토지 이용은 교통지역 3곳, 밭 1곳, 과수원 1곳으로 나타났다. 로드킬이 일어난 주요 지역 특징은 주거지, 농경지 등 인위적인 시설이 인접한 도로에서 발생한 것으로 분석되었다. 잠재지역 예측 분석은 로드킬 지점 개수(n=5)가 적은 관계로 Bootstrap 방법으로 50회 추출하여 분석하였고 환경 인자는 고도, 경사, 향 등 3가지 인자를 사용하였다. AUC값은 0.803이었고, 로드릴 잠재지역 예측에 가장 영향을 준 환경인자는 경사 (68.6%)인 것으로 나타났다. 방사 여우 로드킬 지역은 주거지, 농경지 등 인위시설에 인접한 도로 시설에서 확인되었다. 여우의 안정적인 개체수 증가와 서식지 형성을 통한 성공적인 복원사업을 위해서는 여우 생존을 위협하는 로드킬 예방에 대한 정책 및 관리방 안이 반드시 필요할 것이다. 이를 위해 로드킬 예방을 위한 캠페인, 도로 속도 제한 구역 설정, 로드킬 예방 표지판 설치 등 관리 대책을 마련해야 하고, 복원사업 공감대 형성 및 유지를 위해 지자체 등의 유관기관, 시민단체, 지역주민 등과의 협력이 필요할 것이다. 본 연구는 자동차와 열차의 방사 여우 로드킬 장소를 GIS 와 MaxEnt프로그램을 이용하여 주변 환경 분석 및 잠재 로드킬 지역으로 예측하여 여우 개체수를 감소시키는 원인인 로드킬 지역을 분석함으로써 여우의 생태습성 기작을 밝히는데 기초자료를 제공하는데 의의가 있는 바이다. 하지만 로드킬 지점 개수(n=5)가 부족하여 로드킬에 대한 객관적이고 정확한 결과 도출은 힘든 부분이 있었다. 향후 분석 지점수가 증가하여 확률이 높고 신뢰성 있는 연구 결과를 도출하여야 하여야 할 것이다.