GIN-method를 적용한 암반 그라우팅 주입관리 방법의 제안

During a railway tunnel construction, grouting is often performed to reduce permeability of rock masses and strengthen the ground condition. Management of grout injection in practice has some limitation due to the lack of knowledge regarding the ground condition and injection management criterion. Currently stop criteria of grouting is depending on the maximum pressure of volume of grout. In this paper, a modified GIN (Grouting Intensity Number) technique is discussed, which considers joint features of rock masses. An in situ test was conducted using the modified GIN technique. The optimal grouting injection is conducted by following the GIN envelope. The in situ test results shows reduced permeability of the rock mass, less than 1 Lu.