Improving tactile ground surface indicators based on fuzzy-ahp method: The case of Gulou district, Nanjing, China

Abstract

There are many problems in the practical use of tactile ground surface indicators (TGSIs), and the large amount of TGSI construction currently being carried out does not always have a beneficial impact on the travel of visually impaired groups. Taking the roadside pedestrian space in the Gulou District of Nanjing City as an example, this paper established a TGSI quality evaluation system including six first-level indicators and 24 second-level indicators. The analytic hierarchy process (AHP) was used to determine the weight of the indicators at all levels, and evaluate six urban main roads, six urban secondary main roads and six sidewalks beside access roads, which were selected randomly. Visually impaired people were then asked to evaluate the TGSIs in the pedestrian spaces along these roads. Statistical analysis and evaluation showed that the indicators used in the evaluation system were satisfactory. The evaluation results revealed problems with the standardization, safety, accessibility, continuity, comfort and aesthetics of TGSIs in the urban roadside pedestrian space of Gulou. Analysis of the combined data showed that travel conditions for the visually impaired are currently worse in the old city area than in the new city area and that they are worse in low-grade pedestrian space than along high-grade roads. In order to solve these problems, strategies are put forward for improving the quality of TGSIs in the pedestrian space of Nanjing’s Gulou District in four aspects: improving TGSI structure, optimizing TGSI location, improving the TGSI system, and adapting TGSI implementation according to local conditions.