• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.5
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• pp.160-168
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• 2011

As importance of the field of maintenance and management come to the fore because of collapses of the Seongsu bridge and the Sampoong department store, "Special Act for the Safety Control of Public Structures" was established in 1995 and the major maintenance and management system began taking effect "Detailed inspection and Precision safety diagnosis". However, a technical standard of "Detailed inspection and Precision safety diagnosis" was low because its history was not long, and also the results of research were not enough so anxiety for "Insufficient Detailed inspection and Precision safety diagnosis" was continuously left. While its evaluation system introduced in 2002, the ratio of "Insufficient Detailed inspection and Precision safety diagnosis" has been getting lower. However, according to the evaluation result after carrying out "Detailed inspection and Precision safety diagnosis" recently, it seems difficult to become lower for the ratio of "Insufficient Detailed inspection and Precision safety diagnosis" in future. Therefore, it is considered of questionary survey of the concerned organization and the mechanism side in connection with "Insufficient Detailed inspection and Precision safety diagnosis". So it is arranged the fundamental problems caused by an "Insufficient Detailed inspection and Precision safety diagnosis" that is to show the improving direction of the existing evaluation system in a based on this.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.246-253
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• 2010

National major facilities have been rigorously investigated using regular safety inspections and precision safety diagnosis since the Special Law for Facilities Safety Management was made in 1995. However, the process of safety inspection and precision safety diagnosis could be doubted due to intervention of facility owner for safety level evaluation, competition to obtain low price order, and low technical skills of inspection companies. Although the management processes for evaluating the inspection companies were used for several years, the process should continue to improve in the safety inspection field. This study analyzed the recent evaluation system and the ratios of insufficient inspection. Estimation of national loss expenses to the insufficient safety inspection was investigated to recognize the necessity for the improvement of facility inspection process and evaluation system.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.37-41
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• 2018

Recently, interest in the safety and maintenance of the structures is growing. However, due to the low-cost order placed by the ordering organization, the safety diagnosis specialized institution becomes insolvent and many problems have arisen due to insufficient inspection and diagnosis. Therefore, in this study, the current status of bid cost was examined through the survey of the practitioners and case analysis. As a result, Precision safety inspection is deemed that it is necessary to increase the efficiency of the criteria cost and to strengthen the rigidity of the criteria cost rather than adjusting the criteria cost. Precision safety diagnosis, the criteria cost for structures with a floor area of less than $10,000m^2$ is lowered to 80 % from the current standard. For structures larger than that, the current criteria cost are applied, but it is deemed necessary to strengthen the rigidity of the criteria cost.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.2
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• pp.183-192
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• 2022

Function and performance degradation in tunnel structure can cause road's function loss, proactive maintenance is needed to prevent the initial damage from progressing to intensified damage. Inspection and diagnosis are implemented in accordance with regulations, but it does not fully reflect maintenance processes such as inspection and diagnosis, planning rehabilitation and carrying out. It was carried out for 5,540 cases inspection and diagnosis result in 1,728 tunnels was analyzed to suggest rational maintenance plan in this study.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.6
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• pp.643-653
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• 2020

The concrete lining inspection by inspector after traffic control poses various problems such as congestion caused by traffic control and social loss costs resulting from it, and risks of traffic accidents and safety accidents for inspectors et al. To solve the problems, the concrete lining inspection has been carried out using automatic inspection equipment and image analysis that can be objectively and quantitatively investigated in overseas. In this study, to solve the problems of concrete lining inspection by inspector and to review improvement plan for inspection, inspection was carried out using automatic inspection equipment for ◯◯ tunnel that precision safety diagnosis has been conducted in 2019. Analysis was carried out for both inspection results. Automatic inspection equipment investigated defects in concrete lining such as cracks more accurately than precision safety diagnosis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.2
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• pp.175-184
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• 2000

The maintenance of tunnels is often neglected since tunnels has tendency to become stable with time. The determination of safety of tunnels is a complicated problem. So the role of experienced engineer in the maintenance is very important and development of an expert system which can perform as these engineers has been needed. In this study, an expert system which can determine the safety of tunnels is developed. The developed knowledge base contains the maintenance procedure which is used in KlSTEC(Korea Infrastructure Safety & Technology Corporation). Field test, laboratory test and nondestructive test methods are considered in this knowledge base. Criteria for each item and integrated diagnosis criteria are implemented in the expert system based on literatures and reports. The expert system includes basic inspection. detail inspection and precision inspection. For precision inspection. it has the capacity to exchange the result from numerical analysis by a commercial program FLAC. To verify the expert system. the proposed procedure was compared with an existing tunnel diagnosis report.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.2
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• pp.185-191
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• 2000

The safety problem of aged tunnels has been emphasized. For the effective maintenance, site inspection of tunnel structures and surrounding grounds are required periodically. Also, the determination of safety of tunnels is not a simple problem. So the role experienced engineer in the maintenance is very important and development of an expert system that can perform as the engineers, has been needed. In this study, from the results of numerical analysis in several case, new precision inspection rules which can substitute actual numerical analysis are determined by a commercial program FLAC and regression analysis under various parameters such as material property, lining thickness, overburden and laterial coefficients. They are added to the knowledge base to determine safety of tunnel lining. To verify the expert system, the results are compared with an existing tunnel diagnosis report. It can be concluded that the new rule are well represented the actual numerical analysis under various site conditions. Therefore it is expected that the systematic management for effective maintenance of tunnel structure will be possible.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.3
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• pp.92-99
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• 2021

In the case of precise safety inspection and precise safety diagnosis of a building, a condition evaluation must be conducted to determine the safety grade. Since 2004, an evaluation method using fuzzy theory has been introduced for quantitative condition evaluation,and the relationship and importance of reinforced concrete members using fuzzy theory have been applied. Generally, fuzzy theory is a method used to deal with ambiguous expressions with unclear correlations, but at the time of development, it seems that it was developed by applying fuzzy theory as an alternative in a situation where inspection and diagnosis result data were insufficient. Therefore, it is necessary to verify the relationship and importance of evaluation items derived based on the current fuzzy theory using actual inspection and diagnosis result data.In this study, the correlation between the evaluation items was derived by using the results of 19 precision safety inspections and 9 precision safety inspections and the performance score function formula, and using this, a reasonable durability score calculation formula of the member was presented.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.5
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• pp.33-40
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.323-326
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• 2004

In this study, the inspection path which is considered to free collision is generated by offset surface. When the inspection is executed, the consideration of machine dynamic error increases a precision. Dynamic error is measured on CNC machine bed changing of weight work price. Offset surface is safety space about collision. Because the danger of probe-collision is excluded in Offset surface, it is possible to rapid feed of probe and reduced inspection time. The Program which is possible to simulate using CAIP and is confirmed through actual experiment.