Application of New Type Accelerator for High Quality Shotcrete

고품질 숏크리트 개발을 위한 새로운 급결제 적용

  • 박해균 (삼성물산(주) 건설부문 토목기술팀) ;
  • 이명섭 (삼성물산(주) 건설부문 토목기술팀) ;
  • 김재권 (삼성물산(주) 건설부문 토목기술팀) ;
  • 정명근 ((주)에스코컨설턴트)
  • Published : 2002.03.01

Abstract

From the early 1980's, the New Austrian Tunnelling Method (NATM) has been developed as one of the standard tunnelling methods in Korea. Approximately 10 years ago, wet-mix shotcrete with sodium silicate (waterglass) accelerator was introduced and widely used to tunnel lining and underground support. However, this accelerator had some disadvantages due to the decrease of long-term strength compared to plain concrete (without accelerator) and low quality of the hardened shotcrete. In order to compensate for these disadvantages, recently developed alkali-free accelerator has been successfully demonstrated in numerous projects and applications as a new material to make tunnels more durable and safer. An experimental investigation was carried out in order to verify the strength behavior of wet-mix Steel Fiber Reinforced Shotcrete (SFRS) with alkali-free accelerator. Compressive strength, flexural strength, and flexural toughness were measured by testing specimens extracted from the shotcrete panels. From the results, wet-mix SFRS with alkali-free accelerator exhibited excellent strength improvement compared to the conventional shotcrete accelerator.