快速路复杂桥形标志优化设置方法

为明确复杂桥形标志优化设置方法，选取3种典型城市快速路复杂桥形标志，制定5种设置方法（现状及4种优化方法），开展复杂桥形标志优化设置方法研究。基于驾驶模拟试验，从运行状态、操控行为、行驶效率、主观感受4个层面选取9种评估指标，采用灰色近优评价方法，进行复杂桥形标志不同设置方案的效用评估。结果表明：3种桥形标志的现状设置效用并未达到最优水平，大部分处于中下等水平，有较大提升空间；桥形标志1，2，3的最优设置分别为简化、重复、重复。桥形标志的优化设置能有效改善驾驶人驾驶行为，4种优化方法中，提前设置方法效果较稳定，均使得桥形标志指路效果在一般及以上水平；出口处配合地面文字设置后，桥形标志指路效果在一般水平及以下，设置效用不理想；具有2个出口以上的复杂桥形标志现状设置对驾驶行为影响较差，相关管理部门应对该类型桥形标志加强优化设计设置；不同复杂桥形标志对驾驶人认知、行为影响不同，应进行不同的优化设置，以有效改善驾驶人驾驶行为，快速引导驾驶人寻找目的出口；实际工程应用中，当经济成本、空间条件等因素受限时，可考虑针对复杂桥形标志进行提前设置；不建议出口处设置地面文字，该方法并未达到配合桥形标志改善驾驶行为的效果。

Optimal Setting Methods of Complex Diagrammatic Guide Signs on Urban Expressway

To find the optimization setting methods of complex diagrammatic guide signs, three types of typical complex diagrammatic guide signs of an urban expressway were chosen, and five setting methods (the status and four types of optimization method) were developed in this study to conduct research on an optimization method for complex diagrammatic guide signs. Based on a driving simulation experiment, nine evaluation indexes were selected from four levels, the running state, handling behavior, driving efficiency, and subjective feeling. The grey premium evaluation method was applied to evaluate the effectiveness of different setting methods of complex diagrammatic guide signs. The results show that the status effectiveness of three types of diagrammatic guide signs has not reached the optimal level, and most of them in the middle and lower levels need to be improved. The optimal setting methods of diagrammatic guide signs 1, 2, and 3 are simplified, repeated, and repeated, respectively. The optimal setting methods of complex diagrammatic guide signs can effectively improve the driving behaviors. In the four optimization methods, the influence of the advanced setting method is more stable, which influences the diagrammatic guide sign to reach the general level or higher. When the exit department coordinates with the ground text setting, the guiding effect of three diagrammatic guide signs lies at the general level or lower, which is barely satisfactory. This research reveals that complex diagrammatic guide signs with more than two exits have poor effects on driving behavior. Related management departments should strengthen the optimization setting for this type of sign. Different complex diagrammatic guide signs have different effects on driver cognition and behaviors. To improve the driving behaviors effectively and guide the drivers to find the destination exits quickly, different optimization setting methods should be carried out for them. In practical traffic engineering applications, the setting up of complex diagrammatic guide signs can be considered in advance when the economic cost, spatial conditions, and other factors are limited. It is not recommended to set the ground text at the exit department. This method does not improve the driving behavior under the influence of diagrammatic guide signs.