The recent increase in truck traffic volume and overloading frequency causes a growing need to re-evaluation of fatigue life of steel bridges. However, the traditional fatigue analysis method, that is cumulative damage method(CDM), has limitation to apply to a number of bridges because the required calculation steps are very cumbersome and complicated. This study investigates the feasibility and applicability of proposed simple fatigue evaluation method based on the equivalent damage method (EDM) in Eurocode to estimate the remaining fatigue life for a highway bridge. The Proposed fatigue life evaluation method is as follows; 1. Calculation of fatigue resistance 𝛾𝑀f and fatigue strength Δ𝜎𝑐 used in design, 2. Calculation of partial safety factor 𝛾𝐹f for equivalent stress range, 3. Calculation of stress range Δ𝜎𝐸2 using influence line, 4. Calculation of damage equivalent factor λ, 5. Review of Fatigue state and evaluation of fatigue life. The specifications of the target bridge are as follows; Location : Gyeongbu Expressway, Design Life : 100yr, Construction year : 2006, Total length : 341m, Type of superstructure : continuous steel box girder. The resulting remaining fatigue life estimated by both EDM and CDM have been compared. Remaining fatigue life of target bridge in 2016 was calculated 365yr(EDM using WIM data in 2014), 334yr(CDM using strain gauge data in 2012 and reflecting 2% annual traffic volume increase, Gil and Kang(2012)). As a result of comparison, The remaining fatigue life using proposed method(EDM) was evaluated about 10% higher than the CDM. This result, because traffic volume increase had not reflected when calculation of remaining fatigue life using EDM. Proposed method(EDM) can evaluate remaining fatigue life more easily and simply than CDM.

Bridges have been collapsed due to disaster, and this has required much of expenses. Vehicle collision cause critical damage on Bridges. This paper focus on vehicle collision risk level for highway bridges. In this study use 4 classification, Natural Break based Interval, Equal Interval, Standard Deviation based Interval and Reliability based Interval.

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.

고속도로교량을 위한 위험도기반점검주기를 제안하였다. 고속도로 교량유지관리시스템에서 얻은 상태데이터를 분석하여 교량상태 열화 에 영향을 주는 위해성인자를 찾았다. 그러한 인자와 상태열화사이의 특정한 상관성을 찾았다. 이들을 이용하여 위해성점수를 평가하는데 이용하였다. 여러 가지 위해성 인자들을 종합하여 최종 위해성을 높음, 보통, 낮음의 세 단계로 구분하였다. 취약성은 교량의 현재상태로 평가하였다. 위험도행렬을 점검주기를 위해 제안하였다. C, D, E등급 교량의 점검주기는 현행대로 유지하였다. 그러나, 보통과 높음으로 위 해성이 평가된 A 및 B 등급교량은 점검주기를 최대 6년까지 연장하였고 최소주기는 현행과 같이 3년으로 하였다. 위험도 평가에 따라 점 검주기를 보정하므로써 평균 점검인력을 27% 절약할 수 있었다.

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 by applying the survival analysis probability model. We predicted all of the highway bridge’s conditions in korea depending on budget scenario by the probability model.

This study established key factors causing deck slab deterioration based on GPR database of 747 highway bridges, and predicted deck slab damage rates with respect to bridge service life. To minimize the influence of bridge service life on deck slab deterioration, the deck slab damage rate database was corrected based on a linear regression model of bridge service life vs. deck slab damage rate. The corrected deck slab damage rates were analyzed to determine correlation considering the number of snowy days, the amount of snowfalls, the number of freeze-thaw days, average winter temperature, altitude, the amount of deicing chemicals and equivalent traffic volume, and then both the number of freeze-thaw days and the amount of deicing chemicals were determined to be key factors causing deck slab deterioration. The complex deterioration considering both key factors was represented deck slab damage rate charts, and the average deck slab life was derived. The results of this study will be used as a guideline for highway bridge maintenance to identify the progress of deck slab deterioration for a given bridge and predict the time required deck slab rehabilitation.

Risk Based Inspection(RBI) Period was proposed for highway bridges in Korea. Hazard factors affecting bridge condition deterioration were found by analyzing condition data from Highway Bridge Management System(HBMS). Certain level of correlations between those factors and condition deterioration were found. They are used to evaluate hazard score. Summarizing several hazard factors, final hazard is classified as three level;high, moderate, low. Vulnerability is assessed only by the current state of bridge. Then, risk matrix is suggested for inspection periods. Inspection periods of the bridges with grade C, D, and E are maintained the same as before. But, those of grade A and B with moderate and high hazard score are elongated to maximum 6 years while the maximum inspection period is three years at present. By adjusting inspection period according to risk assessment, it was shown that 27% of average inspection manpower can be saved.

Risk Based Inspection(RBI) Period was proposed for highway bridges in Korea. Hazard factors affecting bridge condition deterioration were found by analyzing condition data from Highway Bridge Management System(HBMS). Certain level of correlations between those factors and condition deterioration were found. They are used to evaluate hazard score. Summarizing several hazard factors, final hazard is classified as three level;high, moderate, low. Vulnerability is assessed only by the current state of bridge. Then, risk matrix is suggested for inspection periods. Inspection periods of the bridges with grade C, D, and E are maintained the same as before. But, those of grade A and B with moderate and high hazard score are elongated to maximum 6 years while the maximum inspection period is three years at present. By adjusting inspection period according to risk assessment, it was shown that 27% of average inspection manpower can be saved.

In this study, discover vulnerable elements of highway bridge by database and analyzing inspection reports. And provide the data so that can explore ways to improve and feedback.

The number of highway bridge has been doubled for last 10 years. It is because many new highway routes has been completed since 2000. As a result, the maintenance cost of highway bridge has been increased as well. Therefore, to predict the long-term maintenance costs, there is a need for a method. To solve this problem, various studies about the life cycle cost analysis was conducted. Maintenance costs for members of the highway bridge is quite different to each other. Therefore, all the elements that are managed by the same proportion is inefficient. In this study, the distribution characteristics of maintenance costs for members of the highway bridge were analyzed using research data and highway bridge maintenance system data.

In this paper, analysis on chloride content and carbonation of concrete members in highway bridge is realized. As a result, it is considered that the amount of snowfall, de-icing salt, freeze and thaw affect chloride content, and concrete members with respect to carbonation in highway bridge are safety at least for now

Degradation characteristics of highway bridge condition rate was studied. Factors affecting degradation rate such as bridge type, member type, and environmental exposure were analyzed by using bridge condition data in Highway Bridge Management System. It can be drawn from the analysis that condition degradation rates are different from type to type of bridge member, and environmental exposure such as the amount of chloride used, the amount of snowfall can accelerate bridge condition degradation

In this paper the change of condition ratings are investigated for old highway bridges. The results of condition ratings are selected from those by professional inspector. The bridges are categorized as four types. The inter-relationship of service life, structural elements, condition ratings are investigated to evaluate the deterioration characteristics of bridges