基于三维地勘数据平台的快速有限元建模方法∗

Fast Finite Element Modeling Based on Geological Data of 3D Visualization Platform

摘要:

随着计算机可视化技术和数值分析方法的快速发展，三维地质建模和有限元技术在岩土工程和城市防灾减灾领域应用越来越广泛。但目前对两者间有效衔接的研究还明显不足，导致了许多重复性工作和较低的工作效率。针对这一问题，提出了一种基于三维地勘数据平台的快速有限元建模方法。利用 Python 语言及其 Mayavi 库开发了基于有限个钻孔的可视化平台，应用两种互补的空间插值法—反距离加权插值法(IDW)和克里格空间插值法(Kriging)实现地层分界面模拟，并进行层间拓扑关系分析优化。重点引入虚拟钻孔概念，提出将三维地层模型截取地块信息转化为有限元软件内置命令文件的衔接方法。以 Plaxis 3D 为例，实现同一大型场地不同地块的快速有限元建模和分析，为未来大规模岩土工程建设和城市防灾减灾的相关分析提供借鉴。

Abstract:

With rapid developments in computer visualization and numerical analysis，3D geological modeling and finite element analysis have been widely applied to geotechnical engineering. The logical connection between 3D geological modeling and finite element modeling， however， hasn’t been ex- ploited efficiently， leading to a high workload and low modeling efficiency. Towards the problem， a fast finite element modeling method based on 3D geological survey data platform was developed. Based on limited boreholes and non-uniform data of boreholes， a visualization platform for strata mod- eling was established using Python programming language. In more detail， the inverse distance weighted (IDW) interpolation method and the Kriging method were employed to identify the interfac- es of soil layers， and then the topological relations between these interfaces were analyzed and opti- mized. With the aid of the concept of virtual boreholes， a data extraction method was proposed to con-vert the regional data of the 3D stratigraphic model into executable files of different commercial finite element software. Taking Plaxis-3D as an example， rapid finite element modeling and analysis for dif- ferent partitions of the same large-scale site were accomplished， illustrating that the presented finite el- ement modeling technique is promising and shall be a future trend in disaster prevention and mitigation of geotechnical engineering.