| 種別 | paper |
| 主題 | BEM Analysis of Mixed-Mode Fracture |
| 副題 | |
| 筆頭著者 | Ali Hassan CHAHROUR（Graduate School of Kumamoto University） |
| 連名者1 | Masayasu OHTSU（Kumamoto University） |
| 連名者2 | Shinichi FUKUCHI（Graduate School of Kumamoto University） |
| 連名者3 | |
| 連名者4 | |
| 連名者5 | |
| キーワード | |
| 巻 | 14 |
| 号 | 2 |
| 先頭ページ | 1011 |
| 末尾ページ | 1016 |
| 年度 | 1992 |
| 要旨 | INTRODUCTION Crack propagation in concrete structures normally takes place under combined action of both tensile (mode-1) and shear (mode-2I) types of loading. Induced mixed-mode fracture complicates the problem for determining crack trajectory and crack instability. Accordingly, the development of a numerical analysis technique for mixed-mode cracking is of utmost importance and a top priority in research on fracture mechanics of concrete. In the present paper, a multi-domain BEM (boundary element method) approach is adopted to analyze mixed-mode cracking in concrete based on linear elastic fracture mechanics (LEFM). The choice of LEFM stems from the fact that nonlinear models for mixed-mode fracture analysis so far have not been fully established yet, Mixed-mode fractures in center-notched concrete beams subjected to anti-symmetric loading and of anchor bolts embedded in concrete blocks are analyzed. Crack propagation is modeled by creating new boundaries in the numerical analysis. In the procedure, stress intensity factors at a notch tip are computed from displacements on the crack tip boundary element. Based on the computation of the direction of crack propagation, a new boundary is created in the multi-domain, which consists of two domains stitched at the interface boundary. Hence, automatic remeshing of the boundary to accomodate the increment of crack growth is carried out, and the prediction of crack trajectories is performed by just creating new boundaries. Thus, crack trajectory based on the criterion of maximum circumferential tensile stress is investigated. CONCLUDING REMARKS The applicability of multi-domain BEM analysis to predict crack trajectories for mixed-mode fracture of concrete was investigated on the basis of linear elastic fracture mechanics (LEFM). The results obtained for the cases of center-notched beams under anti-symmetric loading and pull-out test of anchor bolt embedded in a concrete block are quite suggestive. Still, further research is needed to improve the procedure, and also to clarify the size effect concerning crack propagation in pull-out tests in relation to specimen sizes and configurations. |
| PDFファイル名 | 014-01-2175.pdf |