题目1：Corrosion-Induced Bridge Deterioration

　　报告人：Prof. Sung-Kyoung Lee

　　（President, SK Lee & Associates, Inc., U.S.A, and Affiliated Research Associate at Center for Advanced Infrastructure and Transportation(CAIT), Rutgers University, New Jersey）

　　摘要：Corrosion is a leading cause of bridge deterioration. According to a Federal Highway Administration (FHWA) corrosion cost study in 2001, the estimated total annual direct cost of corrosion in the U.S. is $276 billion or 3.1% of the nation’s Gross Domestic Product. This technical presentation will discuss corrosion costs pertaining to highway bridges in the United States and various types of corrosion-induced deterioration for steel bridges, reinforced concrete bridges, and prestressed concrete bridges. At the end of the presentation, several research studies will be introduced to solve some of the technical challenges.

　　题目2：Study of the influence of Cracks and Surface Coating on the Corrosion of Reinforcing Steel in RC Piers

　　报告人：Prof. Jiunn-shyong Luo

　　（Materials and Chemical Research Lab., Industrial Technology Research Institute, Hsinchu, Taiwan）

　　摘要：It was found that there are irregular cracks occurring on the reinforced concrete (RC) surface of the piers. The causes of cracks are not well identified but could be attributed to improper design, construction practices, and/ or alkali-aggregate reaction (AAR). Since part of the crack depth already exceeded the thickness of the protective cover of concrete, through the cracks, atmospheric corrosive factors (such as moisture, oxygen, and chlorides, etc.) may be able to reach rebar surface directly, promote rebar corrosion, and result in concrete spalling. To understand the influence of cracks on the corrosion of reinforcing steel in the current conditions, time of wetness (TOW) and deposition rate of airborne chlorides at survey areas as well as corrosion potential mapping and corrosion rate measurement of reinforcing steel in the RC piers were investigated.

　　For proactive prevention of rebar corrosion due to chloride intrusion, waterproofing membrane was applied. Even though it is difficult to confirmatively determine the performance of the membrane to rebar corrosion in the present study (because the surveyed RC structures are still in the chloride diffusion stage and do not reach the corrosion threshold level), the membrane already demonstrates its good adhesion properties on the concrete surface. Therefore, continuous or intermittent monitoring of rebar potential and/or corrosion rate over a period of time will provide a more accurate appraisal of the effectiveness of the membrane to rebar corrosion.

　　题目3：Corrosion Resistance Improvement of the Hot Rolled Rebar in Concrete

　　报告人：Dr. Jie Wei

　　（Environmental Corrosion Research Center, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China）

　　摘要：Water-cooled rebar with high strength is promoted to use in concrete for improving the durability and reducing the weight of constructions. Nevertheless, the water-cooled rebar tends to rust both in atmospheric and concrete environment due to its poor corrosion resistance. As the corrosion of rebar occurs on the rebar surface, the oxide scale characteristics of rebar, such as the stability, the compactness and the thickness, affects its corrosion resistance greatly. Therefore, the corrosion resistance of water-cooled rebar can be improved by optimizing the quality of oxide scale on rebar surface. In the present work, a new type of low cost chemical reagent FM was used as the quenching medium instead of water during cooling of the hot-rolled rebar, aiming to improve the oxide scale quality and maintain high mechanical of rebar. The corrosion resistance of the FM-cooled rebar was evaluated comparing with water-cooled and air-cooled rebar both in atmosphere and concrete. The results prove that the corrosion resistance of rebar has been improved greatly by applying FM-cooling process.

　　时间：5月5日（周二）13:30-17:30

　　地点：金属研究所南区报告厅一楼会议室

　　欢迎参加！