A new implementation of the numerical manifold method (NMM) for the modeling of non-collinear and intersecting cracks

نویسندگان

  • Y. C. Cai
  • J. Wu
  • S. N. Atluri
چکیده

The numerical manifold method (NMM), based on the finite covers, unifies the continuum analyses and discontinuum analyses without changing a predefined mathematical mesh of the uncracked solid, and has the advantages of being concise in theory as well as being clear in concept. It provides a natural method to analyze complex shaped strong discontinuities as well as weak discontinuities such as multiple cracks, intersecting cracks, and branched cracks. However, the absence of an effective algorithm for cover generation, to date, is still a bottle neck in the research and application in the NMM. To address this issue, a new method for the generation of the finite covers in the NMM is proposed, for the modeling of cracks. In the present algorithm for cover generation, the physical lines such as joints and cracks are described by geometric functions, the mathematical cover is naturally partitioned into different regions by the physical lines, and the regions belonging to a same physical cover, which contains the end points of the physical lines are identified by a simple calculation of the function values of the physical lines. The present method is simple and robust, and is also very fast because it avoids the usage of the complex geometrical algorithms, and the time-consuming judgment of the point-polygon relations, which are commonly used in the previous literature. Several linear elastic fracture problems are analysed here, to demonstrate the validity and the robustness of the proposed algorithms.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

استفاده از دستگاه مختصات متعامد محلی در مدل کردن ترک دو بعدی به روش المان محدود توسعه یافته

The extended finite element method (X-FEM) is a numerical method for modeling discontinuties, such as cracks, within the standard finite element framework. In X-FEM, special functions are added to the finite element approximation. For crack modeling in linear elasticity, appropriate functions are used for modeling discontinuties along the crack length and simulating the singularity in the crack...

متن کامل

Soil and Rock Slope Stability Analysis based on Numerical Manifold Method and Graph Theory

Limit equilibrium method, strength reduction method and Finite Difference Methods are the most prevalently used methods for soil and rock slope stability analysis. However, it can be mention that those have some limitations in practical application. In the Limit equilibrium method, the constitutive model cannot be considered and many assumptions are needed between slices of soil and rock. The s...

متن کامل

Modified Fixed Grid Finite Element Method in the Analysis of 2D Linear Elastic Problems

In this paper, a modification on the fixed grid finite element method is presented and used in the solution of 2D linear elastic problems. This method uses non-boundary-fitted meshes for the numerical solution of partial differential equations. Special techniques are required to apply boundary conditions on the intersection of domain boundaries and non-boundary-fitted elements. Hence, a new met...

متن کامل

Moving Three Collinear Griffith Cracks at Orthotropic Interface

This work deals with the interaction of P-waves between a moving central crack and a pair of outer cracks situated at the interface of an orthotropic layer and an elastic half-space. Initially, we considered a two-dimensional elastic wave equation in orthotropic medium. The Fourier transform has been applied to convert the basic problem to solve the set of four integral equations. These set of ...

متن کامل

On the crack propagation modeling of hydraulic fracturing by a hybridized displacement discontinuity/boundary collocation method

Numerical methods such as boundary element and finite element methods are widely used for the stress analysis in solid mechanics. This study presents boundary element method based on the displacement discontinuity formulation to solve general problems of interaction between hydraulic fracturing and discontinuities. The crack tip element and a higher order boundary displacement collocation techn...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2013