TDFA (Tire Derived Fuel Ash) is byproduct after burning copped tire fillet in boiler. It contains relatively high SiO2 and CaO components with high Braine over 5,000g/cm3. Nowadays the reclamation site for TDFA is going insufficient and its utilization is strongly required. In the paper, its utilization for cement-based material is introduced. Its detailed strategy and test plans are presented in the related presentation.

Recently, the concern on the deterioration of concrete due to de-icing salts and its counter measurements has been increased. This paper discusses the results from investigation of pre-mature deteriorated existing road-subsidiary concrete structures and the specification of concrete quality.

논문은 고속도로 교량 하부구조 열화를 가속시키는 요인의 하나인 신축이음장치의 손상 조사를 통하여 현황을 분석하고 개선방안을 제시해보고자 한다.

Lateral movement of bridge abutment is frequently causing damages to the expansion joints, bearings, bridge backwall and settlement of approach slabs. In this study, about 1,000 bridges which was lateral movement occur were investigated. The investigation shows that the lateral movement of abutment occurred not only in soft ground, but also in abutment on embankment of the normal soil conditions. The causes of lateral movement included settlement and deformation of high embankment, lateral spread of soft ground, expansion of con'c pavement by alkali-aggregate reaction.

To suggest the preliminary data for effective maintenance of bridge structures, the damage patterns of expressway bridges are quantitatively analyzed in the present study. The defects are the primary damage, and the deterioration occurred around the joint.

Reinforced earth retaining wall is being applied in many construction sites such as slopes, roads, retaining walls with the development of geosynthetic. The case caused a problem with the stability of the reinforced earth retaining walls often occurs because the construction is being conducted, ignoring the basic assumptions of the economical design. In this study, reinforced earth retaining wall damage cases were analyzed in order to derive the causes. The results of this study will be useful for future maintenance of reinforced earth retaining wall.

This paper shows examples of damage of sound barrier supports during maintenance. Main causes of damage are wind load, bad construction and maintenance, vibration due to live load, etc. Finally, the measurements for these damaged cases are introduced in the freeway site.

This paper shows examples of damage cases for corrugated steel plate structures in Korea expressway. There are two representative types of damages. One is a water leak and the other is the deformation of inner section. The results of this study will be useful for future maintenance of corrugated steel plate structures.

It is largely divided into two kinds in freezing phenomenon of the tunnel. Waterproof membrane damage inside the tunnel construction joints leaked into groundwater leak occurs in the icicle and despite the absence of damage to the waterproofing membrane, waterproofing membrane from the back of the ground water is frozen freeze by interfering with smooth drainage this phenomenon is enlarged and local pressure tunnel ceiling, a crack occurred near the side wall is generated

The Goal of research is that budget of maintenance were estimated in network-level bridges. We determined the life cycle of exchangeable bridge element with HBMS(Highway Bridge Management System) data and In-depth Inspection Results by the survival analysis probability model. We developed the method that predicted cost of maintenance in all of the highway bridge in korea considering a characteristics of failures.

Recently, many researches have been conducted to use FBG seonsors in order to measure the effective prestress force in a PSC girder. FBG sensors can be useful to investigate transfer length in prestressed concrete members since they do not have any effect on the bond mechanism between a tendon and concrete. In this research, an experimental program has been conducted to measure transfer length of tendons in high strength concrete members by using FBG sensors. The test results showed that FBG sensors gave a transfer length similar to that measured by concrete surface gauges, but they gave more stable results. This research can be useful for relevant areas such as investigation on the bond mechanism of a tendon in high strength concrete members.

A Finite-Element (FE) model updating method is widely used for identifying structural integrities such as support conditions and material properties. However, it is still difficult to properly estimate support conditions using limited number of data. This study proposed a novel FE model updating method, which can identify support conditions by adding artificial springs at the supports, and by measuring the rotational angles of the supports.

This study propose the embedded sensing system for tensile force estimation of PSC tendon using FBG and EM sensors. Through experimental study, it was found that the tensile force can be estimated by measuring the strain and permeability using proposed sensing system.

This study was performed to analyze the deterioration items of jointed rock slope using the Precision Inspection Results. As a result of study, the deterioration items of jointed rock slope was found out. The results can be utilized for the efficient management.

A cartridge type sensor head was fabricated to detect the level of corrosion in steel cables with consistent or varying cross sections by assessing the LMA (Loss of Metallic Area) damage. Two coil sensor cartridges were made to cater to cables with up to 70mm and 150mm. The developed system was verified through lab experiment using a tapered steel cable specimen, and through a field test conducted in cable bridge. The result showed that the developed system is capable of assessing a cable with varying cross section.

This study was performed to analyze the importances review on deterioration items of concrete retaining wall using statiscal analysis. As a result of study, the main deterioration items of concrete retaining wall were found out and the results can be utilized for the efficient management.