应用无网格方法分析混凝土开裂问题

论文下载

用无网格方法分析钢筋混凝土梁开裂问题
Analysis for the cracking of RC beams with meshless method.

(工程力学, Engineering Mechanics, 21(2), 2004,24~28)

摘要：裂缝处理一直是混凝土数值分析中的一个难点，而无网格方法由于不需要单元网格，非常适用于分析断裂问题，因此可以考虑将其引入混凝土断裂分析领域。本文首先将混凝土中的裂缝分为微观裂缝和宏观裂缝，对于微观裂缝仍然使用传统的弥散裂缝模型；而宏观裂缝则利用无网格方法可以非常方便地调整节点分布的特点，通过增加裂缝节点和裂面边界的方法加以模拟。并给出了宏观裂缝产生，扩展的具体模拟方法。通过算例表明，利用本文提出的方法，可以较准确地分析混凝土宏观裂缝的产生、扩展以及裂缝宽度变化，得到一些传统有限元方法难以得到的计算结果。

关键词：断裂力学，混凝土裂缝，无网格，弥散裂缝，宏观裂缝

Abstract: Simulation of cracking in concrete is difficult by using traditional numerical method. The meshless method is used widely in fracture analysis because no mesh is needed, so it should be able to be applied in the fracture analysis of concrete. In this paper, the cracks in concrete are divided into micro-cracks and macro-cracks. Different crack models are applied for each kind of cracks, respectively. The micro-cracks are represented by the smeared crack model. The macro cracks are represented by additional nodes and edges, with the convenience of adjusting node distribution in meshless method. The details on the simulation of macro-cracks’ appearance and propagations are introduced. The numerical example shows that the presented method can obtain the propagation of macro-cracks in concrete, together with the width of the cracks. Some behaviors which are difficult to be obtained for the traditional finite element method can be gotten.

Keywords: fracture mechanics, concrete crack, meshless, smeared crack, macro-crack

点击下载/Download Here

受弯梁裂缝发展

宏观裂缝及荷载位移曲线

裂缝细部

斜拉破坏混凝土梁