公路隧道格栅式遮光棚几何设计参数研究

A Study on Geometric Design Parameters of Grille Sunshades in Highway Tunnels

为完善格栅式遮光棚的设计参数,利用眼动仪在雅康高速隧道群路段进行实车试验,以驾驶人瞳孔直径变化率以及驾驶人的主观舒适性作为评价指标,验证格栅式遮光棚的遮光效果;在此基础上利用DIALux软件建立了环形和门式2种格栅式遮光棚模型,计算得到格栅式遮光棚在不同洞口朝向和不同格栅间距情况下的遮光率,探明不同参数对遮光棚遮光效果的影响;基于隧道洞口处驾驶人瞳孔面积和环境照度的关系,给出不同设计速度下遮光棚内不同的位置照度要求。研究表明:格栅式遮光棚有效提高了驾驶员在隧道进出口路段的视觉舒适性;环形和门式遮光棚遮光效果并无明显差异;遮光棚两端5~10 m范围内受自然光和隧道洞内暗环境影响,存在较剧烈的明暗过渡;遮光棚中间段照度较为稳定,可作为计算格栅式遮光棚遮光率的依据;洞口朝向对遮光效果影响较大,东西洞口朝向遮光率高于南北洞口朝向遮光率5%~10%;遮光棚内逐级减光并非以线性降低为最佳,设计时可根据照度与速度及距洞口距离的关系式计算或根据现场照度测试结果进行取值。

In order to improve the design parameters of the grille sunshade, vehicle tests are carried out in the tunnel group section of the Ya′an-Kangding expressway with an eye tracker. The change rate of the driver′s pupil diameter and the driver′ s subjective comfort were used as evaluation indicators to verify the shading effect of the grille sunshade. On this basis, two types of grid sunshade models, annular and portal, are built with DIAlux software.The shading rate of grill sunshade under different portal directions and different grill spaces is calculated, and the influence of different parameters on the shading effect of the sunshade is explored. Based on the relationship between the driver′s pupil area at the tunnel portal and the ambient illumination, the illumination requirements for different positions in the sunshade at different design speeds are given. The research shows that the grille sunshade effectively improves the driver′s visual comfort at the entrance and exit of the tunnel. There is no obvious difference in shading effect between circular and portal sunshades. Affected by the natural light and the dark environment in the tunnel, there is a drastic transition between light and dark within the range of 5~10 m at both ends of the sunshade. The illumination of the middle section of the sunshade is relatively stable, which can be used as the basis for calculating the shading rate of the grille sunshade. The portal orientation has a great influence on the shading effect,and the shading rate of the east-west portal orientation is 5%~10% higher than that of the north-south portal orientation. Linear reduction is not the best option for gradual light reduction in the sunshade. The value can be calculated according to the relationship between illuminance and speed and the distance from the portal or according to the field illuminance test results.