DURABILITY DESIGN OF CONCRETE STRUCTURES IN JAPAN: PRESENT AND FUTURE

This paper introduces the durability design in Standard Specification of Concrete Structures issued by Japan Society of Civil Engineers (JSCE) which is considered the most advanced methodology in Japan. The main feature of the durability design is to provide appropriate verification methods for preventing any degradation of structural performance due to deterioration factors during service life. The Standard Specification provides the verification methods for chloride ion penetration, carbonation, freeze–thaw, alkali-silica reaction and chemical attack. This durability design is adopted in other design codes such as JSCE's Guidelines for Performance-Based Design of Steel–Concrete Hybrid Structures and Design Code for Railway Concrete Structures. The latter half of this paper outlines the expected direction of the durability design in Japan and necessary research to improve the present durability design. More advanced durability design is to show how to predict chronological changes (or degradation) of structural performance. Most of the required performance is related to mechanical properties of structures and members, such as strength, stiffness, deformability, and cracking. Thus, the prediction of structural performance should be based on the material properties in damaged concrete structures. The mechanical properties of concrete member damaged by ingress of chloride ion and cyclic freeze-thaw are presented as an example.

• INTRODUCTION

• JSCE STANDARD SPECIFICATIONS FOR CONCRETE STRUCTURES

• EXPECTED DIRECTIONS FOR DURABILITY DESIGN IN JAPAN

• CONCLUSIONS

• REFERENCES