ABSTRACT
Donghyun Kim, Seunghwan Noh & Sangpil Lee GS Engineering & Construction Corp., Seoul, Korea
Byungki Park & Seokwon Jeon Seoul National University, Seoul, Korea
ABSTRACT: In most tunnels in South Korea, blasting has been widely used as an excavation method. The key of blasting method in tunnel is the center-cut, which creates first free surface. This paper introduces new center-cut method named SAV-cut (Stage Advance V-cut) developed on the concept of V-cut. An important factor of SAV-cut is center holes drilled and partly charged for maximizing tensile failure effect and satisfying optimum charge density. Field tests and numerical analysis were carried out to analyze the mechanical behavior and blasting vibration. In the numerical analysis, PFC 2D (Particle Flow Code 2D) was used and two field tests were performed to verify the high performance of SAV-cut. From the results, the newly developed SAV-cut was proved as an effective center-cut method for both increasing blasting efficiency and decreasing blasting vibration.
