中文摘要：

对于平曲线设计超高值的选取,传统方法是基于质点模型——将曲线上行驶的车辆看作一个质点,分析质点的受力特性.我国《公路路线设计规范》JTG D20—2006版本取消了JTJ 011—94版本中圆曲线半径与超高值对应的表格,而《公路工程技术标准》JTG B01—2014中将超高最大值调整为10%,旨在让设计人员有更大的空间合理选用超高值,但也对选用的合理性造成影响.为了保证超高值选用的合理性与安全性,引入安全余量的概念,分析规范中关于超高值选用条文的变化及影响,并提出超高值选用的建议.同时结合工程案例分析计算给出超高选用的建议值,验证利用安全余量评价超高值选取的适用性,为设计人员合理选用超高值提供参考.

英文摘要：

The design of superelevation is generally based up a point-mass model. The relationship between curve radius and superelevation rate is provided in a table of the Design Specification for Highway Alignment JTJ 011—94 version. Nevertheless,that table was removed from the Design Specification for Highway Alignment JTG D20—2006 version. In addition,the maximum superelevation rate is changed to10 percent in the Technical Standard of Highway Engineering（ JTG B01—2014）. More flexibility is given to designers,but the choice of superelevation rate is subject to the experience and knowledge of designers. Therefore,to improve the rationality of road superelevation rate chosen by different designers,a safety margin is introduced. This paper uses the safety margin to analyze the variation in the Specification and the effects,and then develops a few recommendations for existing design criteria. Realworld engineering cases are also used to calculate the recommended superelevation rates. The application of the safety margin is validated. Appropriate superelevation rates can be provided for designers using the safety margin.