• International Journal of Highway Engineering
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• v.13 no.2
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• pp.9-20
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• 2011

Most of domestic expansion joint system was applied by exposed expansion joint system. There are cases where it is damaged by driving. As the result noise and impact happened, and the social cost due to frequent repair works is increasing. So based on the Asphalt Plug Joint(APJ) system that applied in the United States and Europe, new buried expansion joint system was lately developed a system of Buried Folding Lattice Joint(BFLJ) that changed substructure. In this research, we have tested for durability and flexibility performance of buried expansion joint system that based on the type of asphalt mixture. Also we have evaluated for durability of BFLJ system against vehicle load using accelerated pavement testing. As a result of the experiment, the developed BFLJ system gives high flexibility performance and resolves transformation concentration along the joint section more than APJ system. Also it could be seen that the BFLJ system could overcome the disadvantages of APJ and prevent early damage. Because surface deflection of BFLJ system against vehicle load was measured low, and sub system in the buried expansion joint system was not damaged against vehicle load.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.640-643
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• 2008

현재 우리나라는 좁은 국토와 도시 집중화로 인해 급증하고 있는 지하매설물의 체계적인 관리가 어느 때보다 요구되고 있다. 그러나 다른 분야에서 빠르게 진행되고 있는 전산화 및 정보화 작업에 비해 상대적으로 더딘 지리정보체계 구축으로 지하매설물 관리를 위한 정보시스템이 미비한 상태이다. 이는 지리정보체계 구축 방법에 어려움과 소요되는 인력, 비용, 시간 등이 크기 때문으로 판단된다. 본 논문에서는 GPS와 능동형 RFID를 이용한 위치기반 지하매설물 정보시스템의 구현을 기술하고 시뮬레이션하였다. 이 시스템은 GPS NMEA Sentence의 위치정보와 능동형 RFID의 인식정보를 결합한 데이터를 이용하여 정확하고 체계적인 지하매설물 정보 구축이 가능하고, 효율적인 지하매설물 관리를 위한 인터페이스를 제공한다.

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.345-350
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• 2003

• Journal of the Korean GEO-environmental Society
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• v.22 no.11
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• pp.31-37
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• 2021

To prevent accidents due to the cavities and loosened layers formed due to water leakage from the deteriorated buried pipes, evaluation of the changes in water contents around the buried pipes is required. As a method to evaluate the water contents of the soils, time domain reflectometry (TDR) system can be adopted. However, slender electrodes used in standard TDR probe may be damaged when buried in the ground. Thus, in this study, buried type TDR module was developed for the evaluation of the water contents with maintaining required shape of the electrodes in the ground. The TDR module is composed of three electrodes connected to the core conductor and outer conductor and a casing to prevent deformation and maintain alignment of the electrodes in the ground. For the verification of TDR waveforms measured using the TDR module, comparative analysis was conducted with the TDR waveforms measured using the standard TDR probe, and the relationship between the volumetric water content of the soils and the travel time of the guided electromagnetic wave was constructed. In addition, a model test was conducted to test the applicability of the buried type TDR module, and the experimental result shows that the TDR module clearly evaluates the changes in volumetric water contents due to the leakage from the modeled buried pipe. Therefore, the buried type TDR module may be effectively used for the health monitoring of the buried pipe and the evaluation of the water contents around the pipes buried in the urban pavements.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.1
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• pp.1-12
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• 2015

Intrusive Vehicle Detectors have excellent detection performance compared to other types of detector, but disadvantages of high installation and maintenance costs, short life time due to greater damage to roads and paving materials. In contrast, Non-Intrusive Vehicle Detectors attached to the stationary pole have advantages because it does not damage the road surface and easy and less expensive to maintain. Despite these advantages, Non-Intrusive type detectors are still not been widely used in traffic signal control systems because of the low detection performance. In this study, a FMCW(Frequency Modulated Continuous Wave) radar Vehicle Detector was designed as an alternative detector for the signalized intersection, and the performance evaluation was presented by purpose applicability.

• Journal of Sensor Science and Technology
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• v.5 no.6
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• pp.1-6
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• 1996

The feasibility of producing a practical buried fiber optic sensor with high sensitivity for detecting intruders is demonstrated. Experiments were carried out with the use of an all fiber Michelson interferometer, the sensing arm of which was buried in sand. When the sensing arm was buried 8 inches deep in sand, the pressure length product required for a half fringe shift in: the sensor output was $1.09\;kPa{\cdot}m$. The relation between the applied weight and the phase change was almost linear. Experimental results indicated that the sensitivity of the optical fiber sensor was sufficient to detect people on foot and vehicles passing over the buried fiber.

• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.2
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• pp.26-33
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• 2011

Recently, the use of buried glass fiber reinforced plastic (GRP) pipes is widespread and ever increasing trend in the industry. GRP pipes are attractive for use in harsh environments, such as for the collection and transmission of liquids which are abrasive and/or corrosive. The structural behavior of a GRP pipes buried under the ground is different from that of a rigid one made of concrete or clay, for example. A GRP pipe buried under the ground is deflected circumferentially by several percent and the stresses in the pipe are mainly compressive stresses. A GRP pipes has been introduced by a number of manufacturers for selection and used by underground pipeline designers. In all cases, the modified Spangler's equation is recommended by these manufacturers for predicting the ring deflection of these pipes under dead and live loads. In this paper, the ring deflection of buried GRP pipe is evaluated and discussed based on the result of analytical investigation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.3
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• pp.147-153
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• 2017

In this paper, a test is performed to verify the mechanical durability of acoustic sensor system mounted in seabed given test specification. High system durability is required for acoustic sensor system which is costly for installation process, and is affected with various tensional loads by installation equipments. So, it is necessary to verify the system durability including its performance or lifetime in mounted environments. The list of specified tests is mainly based on UJ QTS 200 and the system mostly satisfies the test specification for electrical characteristics.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.12
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• pp.553-558
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• 2014

Geothermal energy can be used with a geothermal heat pump or an earth-to-air heat exchange system (EAHES), which is referred to as a "cooling tube" in Korea. In this study, we suggest EAHES burial guidelines in terms of the parameters of buried pipe length and air velocity regarding the exit air temperature of EAHES. The exit air temperature for EAHES in three regions (Changwon, Busan and Seoul) was calculated with variation in buried pipe length and air velocity at ${\Phi}100mm$ and ${\Phi}200mm$. In conclusion, variation in the buried pipe length is more effective than that of air velocity to achieve the required exit air temperature.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.2
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• pp.140-147
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• 2003

A detection technique is studied to determine the location and the weight of an intruder into infrastructure using fiber optic ROTDR (Rayleigh optical time domain reflectometry) sensor. Fiber optic sensing plates buried in sand are prepared to measure the intruder effects. The signal of ROTDR was analyzed to confirm the detection performance. The constructed ROTDR system could be used up to 12km at the pulse width of 30ns. The location error was less than 3m and the weight could be detected into three levels of grade, such as 20kgf, 40kgf and 60kgf.