外文翻译---日本钢桥建筑的近期发展趋向-建筑结构(编辑修改稿)

外文翻译---日本钢桥建筑的近期发展趋向-建筑结构(编辑修改稿)内容摘要：

g works against increased design live load. – Maximum design live load was changed from 200 kN to 250 kN. （ iii） Retrofitting works due to revised design specifications. – For example, there was no design method for stiffened plates in JSHB about 40 years ago. (iv) Seismic retrofitting works. (v) Development of bridge management systems based on Life Cycle Cost (LCC) and asset management. （ vi） Repair and strengthening works of damage to bridge bearings and expansion joints. （ vii） Maintenance works on permeable pavements. . Maintenance Regarding the maintenance of bridges, there are many issues that can be solved by the bridge engineering munity, though there are also many political and economical problems which cannot be solved by the bridge engineering munity alone. Issues and problems of bridge maintenance are listed below: （ 1） Definition of terminology and life cycle. – Definition of bridge maintenance. – Unification of the terminology on bridge maintenance. – Decision of the life cycle of bridges, members and their parts. （ 2） Inspection and monitoring. – Labor saving of inspection for maintenance through monitoring bridges, members and their parts. – Rationalization and cost reduction of inspection methods. – Education for maintenance engineers. – Collection and storage of maintenance data by utilizing IT technology. （ 3） Evaluation/assessment methods. – Establishment of methods for evaluating the safety and durability of existing bridges and the public announcement and munication of evaluated results. – Development of method for deciding the priority ranking of repair and retrofitting of existing bridges. （ 4） Maintenance system, and repair and retrofitting technique. – Development of bridge maintenance system including repair and retrofitting technique. – Development of effective feedback system from maintenance to design. – Development of techniques for replacing deteriorated bridge structures. – Development of new materials and techniques for maintenance. （ 5） Harmony between bridges and their surrounding environment. – Maintenance considering the coexistence and harmony of aesthetics, – Improvement and refreshment of environment surrounding bridges for users, inhabitants, and nature. （ 6） Budget for maintenance. – Maintenance in case of insufficient budget. – Asset assessment and effective budget. . Seismic design and retrofitting Various design methods, retrofitting methods, technologies and materials for seismic design and retrofitting have been developed after the Hyogoken Nambu Earthquake. The seismic design procedures after the Hyogoken Nambu Earthquake are highlighted below: （ 1） Design seismic loads. There are two levels and two types of design earthquake specified in JSHB. – Level 1: Maximum elastic response acceleration 300 gal. – Level 2 Type I (ocean plate slip type): Maximum elastic response acceleration 1000 gal. – Level 2 Type II (inland fault slip type): Maximum elastic response acceleration 2020 gal. （ 2） Elastic design is carried out against the Level 1 earthquake with the safety factor of . （ 3） Elastoplastic deformation is allowed against Level 2 earthquakes. The safety of a bridge dimensioned on the basis of a Level 1 earthquake is verified by using a Level 2 earthquake. （ 4） Two types of seismic design。