This In paper In this research a experimental and analytical study were performed to investigate strengthening efficiency of a hybrid material beam developed with the goal of simultaneously increasing the flexural stiffness and strength of aging RC structures. A composite beam consisted of two materials ; aluminum, GFRP. The experimental investigation consisted of testing 3 simply supported full-scale concrete beams. As test variables, the cross-sectional type of hybrid material beam(BE-2, SH-2). Test results show that the stiffness and load capacity of all specimens strengthened with hybrid material beam increased compared with unstrengthened specimens. A hybrid material beam of BE-2 was more efficient for stiffness increase than a un non-strengthened beam of U-B. A damage by power pin install reduce flexural load-carry capacity to 7∼10%. Specimens with high reinforcement raito had larg load-carry capacity than specimens with low reinforcement ratio and had small load-carry increase ratio compare with theoretical load-carry capacity of non-strengthen.

The flexural behavior of reinforced concrete (RC) beams strengthened with an iron based-shape memory alloys strip(Fe-SMAs) by a near-surface mounted (NSM) method was evaluated. The pre-strained values of 0% and 4% and introduced prestressing force by an activation of a shape memory effect of the Fe-SMA strengthening material were considered as experimental variables. The experimental results show a large increase in initial stiffness of beams reinforced with 4% pre-strain. On the contrary, The effect of prestressing seems to be insignificant on the yielding and ultimate loads of tensile bars.

This paper presents experimental results for applicability of Fe-based shape memory alloy(Fe-SMA) as near surface mounted(NSM) reinforcement . Three reinforced concrete beams with a width of 300 mm and a height of 200 mm were fabricated for the study. Reinforcement(Non-Reinforced, Reinforced), Activation(Non-Activation, Activation) were considered as experimental variable. Specimens, which reinforced with Fe-SMA have 50% less deflection then non reinforced specimen on 10kN load. Specimens, which activated Fe-SMA has 38% less additional deflection then non activated specimen in 2 weeks.

In this paper, a hydraulic damper was developed to protect the storage racks from earthquakes and the seismic performance of the storage racks was improved by applying the developed damper. In order to achieve these goals, the control capacity for the safety of the storage racks was determined, and a hydraulic damper satisfying the control capacity was designed and manufactured. In addition, the location of the hydraulic damper was determined through simulation. Finally, the shaking table test was carried out. As a result, the seismic performance improvement of the storage racks using the hydraulic damper was confirmed.

The purpose of the safety inspection is to identify the cause of the damage, which is the cause of the safety and performance degradation of the structures, to identify the cause of the damage, and to suggest appropriate repair and strengthening methods. In the traditional safety inspection procedure, the inspection items are selected and the survey contents are recorded in the field book at the time of the field survey. It is not easy to accumulate data and analyze these data as a single project. In this paper, we analyze the problems of the existing facility inspection procedures and conducted studies to build two-way facility safety management system for shortening the processing time and convenience of increasing the efficiency of field work and reporting.

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.

Among various image acquiring technologies which are based on electromagnetic waves, the frequently used imaging technologies in various industries and remote diagnostics, such as spectral, thermal, mm-wave, microwave and short-wave imaging are analyzed in their characteristics and their perspectives as the major diagnostic technologies in public safety areas are described.

It is known that traffic volume, which is representative of live bridge, has a significant effect on service level (LOS: level of service) and structural displacement of bridge. In particular, if the traffic volume is distributed in the traffic congestion time zone on the toll road, it is possible to manage efficiently in terms of customer satisfaction and maintenance management operation such as improvement of service level and structural integrity. To do this, it is necessary to induce the distribution of traffic in the congestion time zone, and it is necessary to apply the differential pricing system such as the congestion charge and the difference of toll by time. In this study, we analyzed traffic aggregation by time zone for the subdivision and advancement of the Gwangan bridge uniform fare system.

The objectives of this research are to suggest the basic plans for earthquake data construction using data sharing platform, and to design the earthquake information contents based on stakeholder's needs. To strengthen the earthquake disaster response capacity, customized contents for public and local/central government use and specific sharing platform are developed. Finally, the step-by-step data sharing roadmap is suggested.

In this study, the severing tests of prestressing steel in old PSCI bridges were carried out. The behavior of the bridge is investigated by measuring the displacement and strain at midpoints of severing girder. The effects of severing some prestressing steel were not noticeable enough to be visible.

This research is a basic study to develop mid - and long - term data base platform for maintenance of aging infrastructure (bridges, tunnels, retaining walls, road facilities, etc. In this study, the degradation and damage data and experiment data obtained from various monitoring technologies are secured in the medium to long term, and the degradation environment and damage model are developed based on the data acquired later. Predicted and standardized services to the management or the people of the nation. In this study, the database will be constructed at the planning, design and implementation stage, and mid - and long - term data will be used for precision safety diagnosis report and monitoring measurement report.

This paper is a study on the development of a data analysis platform that constitutes a part of the development task of the constant monitoring system that can prepare against the earthquake disaster by using the regular measurement data of the old school buildings. The data analysis platform is composed of database management software that manages the metrology data acquired by using the instrument and data management software that analyzes the metrology data, analysis tools that can analyze the metrology data in various ways, A data analysis platform can be used to assess the safety of the school building and evaluate the seismic safety of the old school building to build a system for earthquake disaster.

The motivation of this paper is to identify the variation of stress filed in multi-strand tendon anchorage system using electromechanical impedance measurement. To achieve the objective, the following approaches are implemented. Firstly, stress variation in multi-strand anchorage system due to strand breakage is analyzed to determine the location of impedance acquisition. Secondly, a piezoelectric-based interface technique is designed to localize the damage strand. Lastly, the conceptual design of the PZT-interface is preliminarily verified by an experimental test. Impedance signatures obtained from PZT-interface are quantified by using RMSD index (root-mean-square-deviation). The result shows that the PZT-interface technique is promisingly to identify damage strands.

In this study, vibrational characteristics of upright breakwater under wave condition is numerically analyzed. Firstly, finite element model of upright breakwater which composed by structure-foundation system is established. Dynamic behavior of the upright breakwater’s structure-foundation system is analyzed. Secondly, numerical model for wave field is created. Wave pressure is extracted to apply for the upright breakwater model as the excitation force. Both of design wave and small wave are considered. Thirdly, the vibrational responses are extracted from the upright breakwater model and there model parameters are extracted. Finally, the effect of the wave condition on vibration characteristics of upright breakwater is examined.

In this study, an experimental test is conducted on a concrete specimen using passive thermography (IRT) which is an effective and modern non-destructive test (NDT) method in detecting delaminations. The present work evaluates the detectability of delaminations with different sizes during the daytime by the absolute contrast technique. In addition, the most suitable time for delamination inspection of concrete structures is also proposed.

Many of the facility management information system are being operated by each government departments and Acts. Therefore, it is difficult to share and integrate data through the network because data standard codes are not established. In spite of these problems, the Special Act on the Safety Management and maintenance imposes duties on the main agent of national infra structure management and the maintenance results should be integrated in Infra Structure Information Management System(FMS). Thus we propose the structure classification standard codes for the FMS to integrate and analyze safety and management data.

Many countries are faced with the threats coming from aging of infrastructures and tries to find preparations. In that sense, comprehensive reports have published through performance evaluation on main infrastructures in the USA, Australia, and Japan etc. The government of South Korea shifted the policy from safety-oriented system toward performance-based system. The concept is included in the revised act, “Special Act on the Safety Control and Maintenance of Public Structures”. According to the Special Act, an annual comprehensive report will be issued in Korea. In this paper ‘Infrastructure Evaluation Report’ is analyzed as a reference.

The number of structures that make up the domestic social infrastructure has increased with the development of the national industry, and the social demand for safety due to the aging of structures has also increased. Accordingly, the law stipulating safety and maintenance management for major structures in the country has been revised and it has been implemented since this year. In this study, we will introduce changes to the safety and maintenance system for public structures under the law, analyze the results of inspection and diagnosis of public structures, and consider the status of safety and maintenance.

The purpose of this study is to prevent the occurrence of safety accidents and traffic accidents in winter by presenting the criteria of de-icing and anti-icing of cable-supported marine bridges. In winter, due to the structural characteristics of the cable support bridge, the main tower and the cable are positioned upon the reinforcing beam that the vehicle passes through, and snow and ice that piled on the main tower and the cables is fall to the road. so It can be a reason of the traffic accident. In this study, we analyzed the mechanism for the snow accretion and ice accretion and suggested preventive measures about de-icing and anti-icing.

This study sought to find a new diagnostic method. The drain hole temperature and the upstream water temperature change were measured for 1 year. The purpose of this study was to analyze the correlation between the temperature of the drain hole and the upstream temperature.