摘要
有限元法作为一种求解连体力学问题的有效方法,已经广泛应用于地质领域,本文对软硬夹层的紧闭褶皱的变形应力场进行了二维有限元数值模拟。数值模拟结果表明,在本文的模拟条件下,裂隙的发育位置受破裂指标Fn大于3.0的高值点控制,高值点的密度决定了断裂发育的多少;裂隙的延伸方向与模拟的剪切应力方向一致;裂隙的前端具有代表应力集中的Fn指标值的高值点,断裂沿此生长;当断裂延伸至褶皱核部发生分叉与合并时,应力梯度下降,应力对断裂的控制能力减弱。研究结果对于有限元法应用于实际地质问题具有重要意义。
As an effective method to solve continuum mechanic problems, the finite element method has been used in geology more and more widely, Research on this article carries out a 2D finite element numerical simulation on stratum of interactive soft and hard folds. The result of numerical simulation show that place of fractures raised is controlled by high value of fractures index-Fn index which larger than 3.0 and density of high value determines how many fractures will develop; stretch direction of fractures coincides with simulative result of shear stress; crannies＇ forepart exists high value of Fn index which indicate centralization of stress and factures develop along which; when fractures stretch to core of folds, stress gradient descend and ability of stress make control of fractures is impaired so that it＇s easier for raising of forfication and combination. The research fruit will benefit the application of finite element in case study of geology.
出处
《科技通报》
2006年第5期616-621,共6页
Bulletin of Science and Technology
关键词
褶皱变形
应力模拟
断裂构造
有限元法
fold deformation
stress simulation
fracture structure
finite element method
