APPLICATION OF SELF-CONSOLIDATING CONCRETE TO SEGMENT FOR SHIELD TUNNEL

摘要

In manufacturing conventional shield tunnel segments in Japan,ultra-hard mixed concrete with slump of about 2 cm was used to facilitate molding and to obtain high strength.So,during concrete placement,powerful table vibrators were used for compaction with intense noise and vibration far from ideal.Recently,self-consolidating concrete with slump-flow of about 65 cm is applied to shield tunnel segments.It is possible that three advantages are obtained in a case of the application of self-consolidating concrete.The advantages are the following.(1)improvements of the manufacturing environment: elimination of noise and vibration generated by vibrators on placing concrete(2)rationalization of manufacturing system: change of manufacturing process except concrete placement(3)reduction of manufacturing costs: reduction of labor and equipment for reasons of the rationalization.There are some achievements on the application of Self-Consolidating Concrete to shield tunnel segments at present,total volume has about 12,000 m3(about 1,500 rings)including maximum diameter size of 7,100 mm and minimum diameter size of 3,600 mm.This paper shows that Self-Consolidating Concrete gives a new variable method to manufacturing concrete products such as shield tunnel segment.