三次B样条在隧道断面拟合中的应用研究

摘要

Based on the study of the inadequateness of existing methods for fitting tunnel section, in view of the unique advantages of flexibility for cubic B-spline, this paper presents respectively cubic spline and cubic B-spline according to arc tunnel and straight wall type section. And the fitting effect is evaluated with the distance between the point on the fitting curve and the standard cross-section curve. The above process is programmed on MATLAB7. 0 platform to evaluate the effects of spline fitting, and the results show that cubic B-spline achieves better fitting for those curves with mutation points ( cusps) of straight wall tunnel section.%在研究已有隧道断面拟合方法不足的基础上，鉴于三次B样条灵活的独特优势，对圆弧型隧道和直墙型隧道断面分别采用三次样条和三次B样条进行拟合，并通过求取拟合曲线上点到标准断面曲线的距离对拟合效果进行评价。在Matlab7.0平台上编程实现上述过程，对样条拟合效果进行评价，结果表明，对于直墙型存在突变点类型的曲线，三次B样条曲线相对于三次样条曲线拟合效果更好。