Application of Mechanical Crack Model to Numerical Study of Rock Mass Behavior

Do-hyun Park; Seok-won Jeon

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2000 Vol.2, Issue 2 Preview Page

Application of Mechanical Crack Model to Numerical Study of Rock Mass Behavior 암석거동의 수치해석적 연구를 위한 균열모형의 적용

30 September 2000. pp. 72-85

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Abstract

Rock is a very complex and heterogeneous material, containing structural flaws due to geologic generation process. Because of those structural flaws, deformation and failure of rock when subjected to differential compressive stresses is non-linear. To simulate the non-linear behavior of rock, mechanical crack models, that is, sliding and shear crack models have been used in several studies. In those studies, non-linear stressstrain curves and various behaviors of rock including the changes of effective elastic moduli (E₁, E₂, ν₁, ν₂, G₂) due to crack growth were simulated (Kemeny, 1993; Jeon, 1996, 1998). Most of the studies have mainly focused on the verification of the mechanical crack model with relatively less attempt to apply it to practical purposes such as numerical analysis for underground and/or slope design. In this study, the validity of mechanical crack model was checked out by simulating the non-linear behavior of rock and consequently it was applied to a practical numerical analysis, finite element analysis commonly used.

Keywords

Crack model

Non-linear behavior

Critical crack length

FEM

Slidng crack

Shear crack

암석은 지질학적 생성과정으로 인해 잠재적으로 많은 구조적 결함을 내포하고 있는 재료이다. 이러한 구조적 결함으로 인해 압축하중을 받고 있는 암석의 변형거동 및 파괴는 비선형적이다. 지금까지의 연구들에서는 암석의 비선형 거동을 모사하기 위해 균열모형, 즉 활주균열모형 (Sliding crack model)과 전단균열모형 (Shear crack model)을 사용하였다. 이 연구들에서는 암석의 비선형 응력-변형률 곡선과 균열성장으로 인해 발생되는 유효탄성정수들(E1, E2, ν1, ν2, G2)의 변화와 같은 여러 가지 암석 거동을 모사하였다(Kemeny, 1993; Jeon, 1996, 1998). 대부분의 이러한 연구들은 주로 균열모형의 암석거동의 적용에 대한 타당성을 검증하는데 그쳤으며 지하공간이나 사면설계 등의 실제적인 수치해석을 목적으로 균열모형을 적용한 연구는 그다지 많지 않다. 본 연구에서는 암석의 비선형 응력-변형률 곡선을 모사함으로써 균열모형의 암석에의 적용에 대한 타당성을 검증하며 실제적인 수치해석, 즉 상용되고 있는 유한요소해석 프로그램에 균열모형을 적용하였다.

키워드

균열모형

비선형거동

한계균열길이

유한요소해석

활주균열

전단균열

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Information

Publisher :Korean Tunneling and Underground Space Association
Publisher(Ko) :한국터널지하공간학회
Journal Title :Journal of Korean Tunnelling and Underground Space Association
Journal Title(Ko) :한국터널지하공간학회 논문집
Volume : 2
No :2
Pages :72-85

Journal of Korean Tunnelling and Underground Space Association ISSN:2233-8292(Print) 2287-4747(Online) 한국터널지하공간학회 논문집

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